TY - JOUR TI - Shelf-scale mapping of fish sound production with ocean gliders AU - Mann, David AU - Wall, Carrie AU - Lembke, Chad AU - Lindemuth, Michael AU - He, Ruoying AU - Taylor, Chris AU - Kellison, Todd T2 - The Journal of the Acoustical Society of America AB - Ocean gliders are a powerful platform for collecting large-scale data on the distribution of sound-producing animals while also collecting environmental data that may influence their distribution. Since 2009, we have performed extensive mapping on the West Florida Shelf with ocean gliders equipped with passive acoustic recorders. These missions have revealed the distribution of red grouper as well as identified several unknown sounds likely produced by fishes. In March 2014, we ran a mission along the shelf edge from Cape Canaveral, FL to North Carolina to map fish sound production. The Gulf Stream and its strong currents necessitated a team effort with ocean modeling to guide the glider successfully to two marine protected areas. This mission also revealed large distributions of unknown sounds, especially on the shallower portions of the shelf. Gliders provide valuable spatial coverage, but because they are moving and most fish have strong diurnal sound production patterns, data analysis on presence and absence must be made carefully. In many of these cases, it is best to use a combination of platforms, including fixed recorders and ocean profilers to measure temporal patterns of sound production. DA - 2014/10// PY - 2014/10// DO - 10.1121/1.4899624 VL - 136 IS - 4 SP - 2117-2117 ER - TY - JOUR TI - Seasonal and interannual variability in Gulf of Maine hydrodynamics: 2002--2011 T2 - Deep Sea Research Part II: Topical Studies in Oceanography DA - 2014/// PY - 2014/// VL - 103 SP - 210-222 ER - TY - JOUR TI - Numerical investigation of coastal circulation dynamics near Cape Hatteras, North Carolina, in January 2005 AU - Gong, Yanlin AU - He, Ruoying AU - Gawarkiewicz, Glen G. AU - Savidge, Dana K. T2 - Ocean Dynamics AB - A realistic regional ocean model is used to hindcast and diagnose coastal circulation variability near Cape Hatteras, North Carolina, in January 2005. Strong extratropical winter storms passed through the area during the second half of the month (January 15–31), leading to significantly different circulation conditions compared to those during the first half of the month (January 1–14). Model results were validated against sea level, temperature, salinity, and velocity observations. Analyses of along-shelf and cross-shelf transport, momentum, and kinetic energy balances were further performed to investigate circulation dynamics near Cape Hatteras. Our results show that during the strong winter storm period, both along-shelf (southward) and cross-shelf (seaward) transport increased significantly, mainly due to increases in geostrophic velocity associated with coastal sea level setup. In terms of momentum balance, the wind stress was mainly balanced by bottom friction. During the first half of month, the dominant kinetic energy (KE) balance on the shelf was between the time rate of KE change and the pressure work, whereas during the stormy second half of month, the main shelf KE balance was achieved between wind stress work and dissipation. DA - 2014/11// PY - 2014/11// DO - 10.1007/s10236-014-0778-6 VL - 65 IS - 1 SP - 1-15 ER - TY - JOUR TI - Coastal connectivity in the Gulf of Maine in spring and summer of 2004--2009 AU - Li, Yizhen AU - He, Ruoying AU - Manning, James P T2 - Deep Sea Research Part II: Topical Studies in Oceanography DA - 2014/// PY - 2014/// VL - 103 SP - 199-209 ER - TY - JOUR TI - Seasonal and interannual variability in Gulf of Maine hydrodynamics: 2002--2011 T2 - Deep Sea Research Part II: Topical Studies in Oceanography DA - 2014/// PY - 2014/// VL - 103 SP - 210-222 ER - TY - JOUR TI - A red tide of Alexandrium fundyense in the Gulf of Maine T2 - Deep Sea Research Part II: Topical Studies in Oceanography DA - 2014/// PY - 2014/// VL - 103 SP - 174-184 ER - TY - JOUR TI - A red tide of Alexandrium fundyense in the Gulf of Maine T2 - Deep Sea Research Part II: Topical Studies in Oceanography DA - 2014/// PY - 2014/// VL - 103 SP - 174-184 ER - TY - JOUR TI - Trait-based scaling of temperature-dependent foliar respiration in a species-rich tropical forest canopy AU - Slot, Martijn AU - Rey-Sánchez, Camilo AU - Winter, Klaus AU - Kitajima, Kaoru T2 - Functional Ecology AB - Summary The scarcity of empirical data on leaf respiration ( R ) and its temperature sensitivity (e.g. Q 10 , defined as the proportional increase in R per 10 °C warming) causes uncertainty in current estimates of net primary productivity of tropical forests. We measured temperature response curves of R on 123 upper‐canopy leaves of 28 species of trees and lianas from a tropical forest in Panama and analysed variations in R and Q 10 in relation to other leaf functional traits. Respiration rates per leaf area at 25 °C ( R A ) varied widely among species and were significantly higher in trees than in lianas. R A was best predicted by a multiple regression model containing leaf phosphorus concentration, photosynthetic capacity and leaf mass per area ( r 2 = 0·64). The mean Q 10 value (2·4) was significantly higher than the commonly assumed value of 2·0. Q 10 was best predicted by the combination of leaf carbohydrate concentration and growth form (trees vs lianas) ( r 2 = 0·26). The night‐time leaf respiratory carbon flux from this tropical forest was calculated from these multiple regression models to be 4·5 Mg C ha −1 year −1 , with an estimated additional 2·9 Mg C ha −1 year −1 being released by respiration during the day. Trait‐based modelling has potential for estimating R , thus facilitating carbon flux estimation in species‐rich tropical forests. However, in contrast to global analyses, leaf phosphorus content was the most important correlate of R and not leaf nitrogen, so calibration of trait models to the tropics will be important. Leaf traits are poor predictors of Q 10 values, and more empirical data on the temperature sensitivity of respiration are critically needed to further improve our ability to scale temperature‐dependent respiration in species‐rich tropical forests. DA - 2014/3/24/ PY - 2014/3/24/ DO - 10.1111/1365-2435.12263 VL - 28 IS - 5 SP - 1074-1086 J2 - Funct Ecol LA - en OP - SN - 0269-8463 UR - http://dx.doi.org/10.1111/1365-2435.12263 DB - Crossref ER - TY - JOUR TI - Thermal acclimation of leaf respiration of tropical trees and lianas: response to experimental canopy warming, and consequences for tropical forest carbon balance AU - Slot, Martijn AU - Rey-Sánchez, Camilo AU - Gerber, Stefan AU - Lichstein, Jeremy W. AU - Winter, Klaus AU - Kitajima, Kaoru T2 - Global Change Biology AB - Abstract Climate warming is expected to increase respiration rates of tropical forest trees and lianas, which may negatively affect the carbon balance of tropical forests. Thermal acclimation could mitigate the expected respiration increase, but the thermal acclimation potential of tropical forests remains largely unknown. In a tropical forest in Panama, we experimentally increased nighttime temperatures of upper canopy leaves of three tree and two liana species by on average 3 ° C for 1 week, and quantified temperature responses of leaf dark respiration. Respiration at 25 ° C ( R 25 ) decreased with increasing leaf temperature, but acclimation did not result in perfect homeostasis of respiration across temperatures. In contrast, Q 10 of treatment and control leaves exhibited similarly high values (range 2.5–3.0) without evidence of acclimation. The decrease in R 25 was not caused by respiratory substrate depletion, as warming did not reduce leaf carbohydrate concentration. To evaluate the wider implications of our experimental results, we simulated the carbon cycle of tropical latitudes (24 ° S–24 ° N) from 2000 to 2100 using a dynamic global vegetation model ( LM 3 VN ) modified to account for acclimation. Acclimation reduced the degree to which respiration increases with climate warming in the model relative to a no‐acclimation scenario, leading to 21% greater increase in net primary productivity and 18% greater increase in biomass carbon storage over the 21st century. We conclude that leaf respiration of tropical forest plants can acclimate to nighttime warming, thereby reducing the magnitude of the positive feedback between climate change and the carbon cycle. DA - 2014/5/8/ PY - 2014/5/8/ DO - 10.1111/gcb.12563 VL - 20 IS - 9 SP - 2915-2926 J2 - Glob Change Biol LA - en OP - SN - 1354-1013 UR - http://dx.doi.org/10.1111/gcb.12563 DB - Crossref ER - TY - JOUR TI - Western Pacific atmospheric nutrient deposition fluxes, their impact on surface ocean productivity AU - Martino, M. AU - Hamilton, D. AU - Baker, A. R. AU - Jickells, T. D. AU - Bromley, T. AU - Nojiri, Y. AU - Quack, B. AU - Boyd, P. W. T2 - Global Biogeochemical Cycles AB - Abstract The atmospheric deposition of both macronutrients and micronutrients plays an important role in driving primary productivity, particularly in the low‐latitude ocean. We report aerosol major ion measurements for five ship‐based sampling campaigns in the western Pacific from ~25°N to 20°S and compare the results with those from Atlantic meridional transects (~50°N to 50°S) with aerosols collected and analyzed in the same laboratory, allowing full incomparability. We discuss sources of the main nutrient species (nitrogen (N), phosphorus (P), and iron (Fe)) in the aerosols and their stoichiometry. Striking north–south gradients are evident over both basins with the Northern Hemisphere more impacted by terrestrial dust sources and anthropogenic emissions and the North Atlantic apparently more impacted than the North Pacific. We estimate the atmospheric supply rates of these nutrients and the potential impact of the atmospheric deposition on the tropical western Pacific. Our results suggest that the atmospheric deposition is P deficient relative to the needs of the resident phytoplankton. These findings suggest that atmospheric supply of N, Fe, and P increases primary productivity utilizing some of the residual excess phosphorus (P*) in the surface waters to compensate for aerosol P deficiency. Regional primary productivity is further enhanced via the stimulation of nitrogen fixation fuelled by the residual atmospheric iron and P*. Our stoichiometric calculations reveal that a P* of 0.1 µmol L −1 can offset the P deficiency in atmospheric supply for many months. This study suggests that atmospheric deposition may sustain ~10% of primary production in both the western tropical Pacific. DA - 2014/7// PY - 2014/7// DO - 10.1002/2013gb004794 VL - 28 IS - 7 SP - 712-728 UR - http://dx.doi.org/10.1002/2013gb004794 ER - TY - JOUR TI - Occurrence of pristine aerosol environments on a polluted planet AU - Hamilton, Douglas S. AU - Lee, Lindsay A. AU - Pringle, Kirsty J. AU - Reddington, Carly L. AU - Spracklen, Dominick V. AU - Carslaw, Kenneth S. T2 - Proceedings of the National Academy of Sciences AB - Natural aerosols define a preindustrial baseline state from which the magnitude of anthropogenic aerosol effects on climate are calculated and are a major component of the large uncertainty in anthropogenic aerosol-cloud radiative forcing. This uncertainty would be reduced if aerosol environments unperturbed by air pollution could be studied in the present--day atmosphere, but the pervasiveness of air pollution makes identification of unperturbed regions difficult. Here, we use global model simulations to define unperturbed aerosol regions in terms of two measures that compare 1750 and 2000 conditions-the number of days with similar aerosol concentrations and the similarity of the aerosol response to perturbations in model processes and emissions. The analysis shows that the aerosol system in many present-day environments looks and behaves like it did in the preindustrial era. On a global annual mean, unperturbed aerosol regions cover 12% of the Earth (16% of the ocean surface and 2% of the land surface). There is a strong seasonal variation in unperturbed regions of between 4% in August and 27% in January, with the most persistent conditions occurring over the equatorial Pacific. About 90% of unperturbed regions occur in the Southern Hemisphere, but in the Northern Hemisphere, unperturbed conditions are transient and spatially patchy. In cloudy regions with a radiative forcing relative to 1750, model results suggest that unperturbed aerosol conditions could still occur on a small number of days per month. However, these environments are mostly in the Southern Hemisphere, potentially limiting the usefulness in reducing Northern Hemisphere forcing uncertainty. DA - 2014/12/30/ PY - 2014/12/30/ DO - 10.1073/pnas.1415440111 VL - 111 IS - 52 SP - 18466-18471 UR - http://dx.doi.org/10.1073/pnas.1415440111 KW - natural aerosol KW - pristine regions KW - radiative forcing KW - preindustrial KW - baseline ER - TY - CONF TI - How important is seismically-induced erosion above the Cascadia subduction zone? Insights from the stratigraphy of large lakes on the Olympic Peninsula, Washington State AU - Wegmann, K.W. AU - Leithold, E.L. AU - Bohnenstiehl, D.R. A2 - Gillespie, A. A2 - Montgomery, D. C2 - 2014/// C3 - Proceedings of the 23rd Biennial Meeting of the American Quaternary Association DA - 2014/// VL - 23 SP - 35–37 PB - University of Washington, American Quaternary Union ER - TY - JOUR TI - Experiments of artificially triggered lightning and its application in Conghua, Guangdong, China AU - Zhang, Yijun AU - Yang, Shaojie AU - Lu, Weitao AU - Zheng, Dong AU - Dong, Wansheng AU - Li, Bin AU - Chen, Shaodong AU - Zhang, Yang AU - Chen, Luwen T2 - Atmospheric Research AB - The Guangdong Comprehensive Observation Experiment on Lightning Discharge (GCOELD) was conducted from 2006 to 2011 in Conghua, Guangdong, China. In GCOELD, the acoustical, optical, electrical and magnetic signals of triggered lightning and natural lightning were measured. For the triggered lightning, the peak current of the return strokes (RSs) ranged from 6.67 to 31.93 kA. The transferred charge within 1 ms after the beginning of the RS ranged from 0.44 to 4.16 C. The peak currents showed different-function correlations with average rate of rise between 10 and 90%, maximum rate of rise, charge transfer and action integral. The 2D propagation speed of the upward positive leader for the triggered lightning was of the order of 104–105 m s− 1. The speed of the downward negative leader involved in altitude-triggered lightning was approximately 105 m s− 1. The characteristics of induced voltages produced by triggered lightning on a power line and signal line of an automatic weather station were measured and analyzed. The maximum induced voltage generated by the RS on the overhead power line (1200 m in length and 2 m above the ground) exceeded 10 kV. The maximum induced voltage on a vertical 10-m signal line was 3.10 kV. The triggered-lightning technique was also used to test the detection efficiency and location precision of the lightning location system (LLS) in Guangdong. It was explored that the Guangdong LLS yielded detection efficiency and location error of 92% and 760 m, respectively, for triggered flashes. For RSs of the triggered lightning, the peak currents given by the LLS deviated from those measured at the base of the lightning channel by 16% on average. DA - 2014/1// PY - 2014/1// DO - 10.1016/J.ATMOSRES.2013.02.010 VL - 135-136 SP - 330-343 J2 - Atmospheric Research LA - en OP - SN - 0169-8095 UR - http://dx.doi.org/10.1016/J.ATMOSRES.2013.02.010 DB - Crossref KW - Rocket-triggered lightning KW - Return stroke current KW - Induced voltages ER - TY - CHAP TI - Raster-based analysis AU - Hardin, E. AU - Mitasova, H. AU - Tateosian, L. AU - Overton, M. T2 - SpringerBriefs in Computer Science AB - Raster-based analysis on two or more DEMs can provide information about change patterns and trends. A common approach to mapping elevation change between two surveys is DEM differencing, performed by map algebra within GIS (r.mapcalc in GRASS). For a larger number of elevation data snapshots, per cell statistics can be applied to the raster DEMs to derive summary maps, which reveal the spatial patterns of stable and dynamic sites, the time periods when sites reach their highest or lowest elevations, and the trends in elevation change. PY - 2014/// DO - 10.1007/978-1-4939-1835-5_3 VL - 0 SP - 27-34 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84990851424&partnerID=MN8TOARS ER - TY - CHAP TI - Processing coastal lidar time series AU - Hardin, E. AU - Mitasova, H. AU - Tateosian, L. AU - Overton, M. T2 - SpringerBriefs in Computer Science AB - In this chapter, we analyze time series of lidar data point clouds to assess the point density, gaps in coverage, spatial extent and accuracy. Based on this analysis and a given application we select appropriate resolution and interpolation method for computation of raster-based digital elevation model (DEM). We explain computation of DEMs by per raster-cell averaging, two types of splines. Assessment of systematic error using geodetic benchmarks or other ground truth point data and correction of any shifted DEMs is the final step in creating a consistent DEM time series. PY - 2014/// DO - 10.1007/978-1-4939-1835-5_2 VL - 0 SP - 7-25 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84990851417&partnerID=MN8TOARS ER - TY - CHAP TI - Introduction AU - Hardin, E. AU - Mitasova, H. AU - Tateosian, L. AU - Overton, M. T2 - SpringerBriefs in Computer Science AB - Management of highly dynamic coastal landscapes requires repeated mapping and analysis of observed changes. Modern remote sensing techniques, such as lidar, increased the frequency and level of detail in coastal surveys and new methods were developed to extract valuable information from these data using Geographic Information Systems (GIS). In this chapter we discuss mapping of coastal change, on-line data resources, and the basics of installation and working with open source GRASS GIS used in this book. PY - 2014/// DO - 10.1007/978-1-4939-1835-5_1 VL - 0 SP - 1-6 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85045018146&partnerID=MN8TOARS ER - TY - CHAP TI - Feature extraction and feature change metrics AU - Hardin, E. AU - Mitasova, H. AU - Tateosian, L. AU - Overton, M. T2 - SpringerBriefs in Computer Science AB - Coastal change has been historically measured by metrics derived for specific coastal linear features such as shorelines. Linear features are also important for measuring sand dune migration based on the location of dune crests and slip faces and for prediction of coastal vulnerability. In this chapter we present methods for extracting shorelines, dune ridges, dune crests and building footprints from DEMs. Then we measure the change of these features and use them to map vulnerability to storms. PY - 2014/// DO - 10.1007/978-1-4939-1835-5_4 VL - 0 SP - 35-62 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85045013232&partnerID=MN8TOARS ER - TY - CHAP TI - Volume analysis AU - Hardin, E. AU - Mitasova, H. AU - Tateosian, L. AU - Overton, M. T2 - SpringerBriefs in Computer Science PY - 2014/// DO - 10.1007/978-1-4939-1835-5_5 VL - 0 SP - 63-70 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85045012430&partnerID=MN8TOARS ER - TY - CHAP TI - Visualizing coastal change AU - Hardin, E. AU - Mitasova, H. AU - Tateosian, L. AU - Overton, M. T2 - SpringerBriefs in Computer Science AB - Scientific visualization provides a means for effective analysis and communication of complex information that may be otherwise difficult to explain and explore. This particularly applies to coastal geomorphology, where 3D spatial and temporal patterns and relationships are critical for capturing landscape features and their dynamics. In this chapter we present GIS-based techniques for visualizing dynamic coastal landscapes using 2D maps, 3D perspective views, animations, and the space-time cube approach. PY - 2014/// DO - 10.1007/978-1-4939-1835-5_6 VL - 0 SP - 71-80 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85045013018&partnerID=MN8TOARS ER - TY - CONF TI - Attribution of Extreme Temperature Events for the Western US using a superensemble of Regional Climate Model Simulations AU - Mera, Roberto J. AU - Mote, P. AU - Allen, M.R. T2 - 26th Conference on Climate Variability and Change at the American Meteorological Society Meeting C2 - 2014/// CY - Atlanta, Georgia DA - 2014/// PY - 2014/2// ER - TY - CONF TI - Attribution of low precipitation in California during the winter of 2013-2014 AU - Mera, Roberto J. AU - Ekwurzel, B. AU - Rupp, D. T2 - American Geophysical Union (AGU) Fall Meeting C2 - 2014/// CY - San Francisco, California DA - 2014/// PY - 2014/12// ER - TY - CONF TI - Northeast tropical/extra-tropical cyclone case studies: Irene (2011) and Sandy (2012) AU - Zambon, J.B. AU - He, R. AU - Warner, J.C. T2 - Coastal Processes Project Meeting C2 - 2014/// CY - Woods Hole Oceanographic Institute, Woods Hole, MA DA - 2014/// PY - 2014/// ER - TY - THES TI - Air-sea interaction during landfalling tropical and extra-tropical cyclones AU - Zambon, J.B. DA - 2014/// PY - 2014/// M3 - Ph.D. Dissertation PB - North Carolina State University UR - http://repository.lib.ncsu.edu/ir/handle/1840.16/9951 ER - TY - CONF TI - Investigation of Hurricane Sandydynamics using the 3-way Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) model AU - Zambon, J.B. AU - He, R. AU - Warner, J.C. T2 - American Geophysical Union (AGU) Ocean Sciences Meeting C2 - 2014/// CY - Honolulu, HI DA - 2014/// PY - 2014/2/23/ ER - TY - CONF TI - Tropical to extratropical: marine environmental changes associated with Superstorm Sandy prior to its landfall AU - Zambon, J.B. T2 - Marine, Earth and Atmospheric Sciences (MEAS) and Forestry and Environmental Resources (FER) Graduate Research Symposium C2 - 2014/// CY - North Carolina State University, Raleigh, NC DA - 2014/// PY - 2014/// ER - TY - CHAP TI - Progress in nitrogen deposition monitoring and modelling AU - Aas, W. AU - Carou, S. AU - Alebic-Juretic, A. AU - Aneja, V.P. AU - Balasubramanian, R. AU - Berge, H. AU - Cape, J.N. AU - Delon, C. AU - Denmead, O.T. AU - Dennis, R.L. AU - Dentener, F. AU - Dore, A.J. AU - Du, E. AU - Forti, M.C. AU - Galy-Lacaux, C. AU - Geupel, M. AU - Haeuber, R. AU - Iacoban, C. AU - Komarov, A.S. AU - Kubin, E. AU - Kulshrestha, U.C. AU - Lamb, B. AU - Liu, X. AU - Patra, D.D. AU - Pienaar, J.J. AU - Pinho, P. AU - Rao, P.S.P. AU - Shen, J. AU - Sutton, M.A. AU - Theobald, M.R. AU - Vadrevu, K.P. AU - Vet, R. T2 - Nitrogen Deposition, Critical Loads and Biodiversity: Proceedings of the International Nitrogen Initiative Workshop, Linking Experts of the Convention on Long-Range Transboundary Air Pollution and the Convention on Biological Diversity PY - 2014/// DO - 10.1007/978-94-007-7939-6_48 SP - 455-463 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84922990752&partnerID=MN8TOARS ER - TY - CHAP TI - Ammonia emissions in the US: Assessing the role of bi-directional ammonia transport using the community multi-scale air quality (CMAQ) model AU - Gore, M.L. AU - Cooter, E.J. AU - Dennis, R.L. AU - Pleim, J.E. AU - Aneja, V.P. T2 - Nitrogen Deposition, Critical Loads and Biodiversity: Proceedings of the International Nitrogen Initiative Workshop, Linking Experts of the Convention on Long-Range Transboundary Air Pollution and the Convention on Biological Diversity PY - 2014/// DO - 10.1007/978-94-007-7939-6_4 SP - 31-38 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84948122259&partnerID=MN8TOARS ER - TY - CHAP TI - Studying Aerosol-Cloud-Climate Interactions over East Asia Using WRF/Chem AU - Zhang, Yang AU - Zhang, Xin AU - Cai, Changjie AU - Wang, Kai AU - Wang, Litao T2 - Air Pollution Modeling and its Application XXIII A2 - Steyn, D. A2 - Mathur, R. T3 - Springer Proceedings in Complexity AB - East Asia provides an ideal testbed to study aerosol feedbacks into climate via direct and indirect effects because of high anthropogenic emissions and unique climatology. In this work, an online coupled meteorology-chemistry model, WRF/Chem, is applied to simulate air quality and climate interactions for multiple months in 2001, 2005, and 2008 to characterize long-term seasonal variations of pollutant concentrations and quantify the contributions of anthropogenic aerosols to aerosol direct and indirect effects. The results show a reasonably good performance for most meteorological variables and chemical species concentrations. Large biases in some variables may be caused by large uncertainties in emissions. Anthropogenic aerosols in East Asia can reduce the surface net solar radiation by up to 6 % and enhance cloud condensation nuclei and cloud droplet number concentrations by a factor of up to 3 on domain-average, with much greater impacts over urban areas. These results suggest that aerosol feedbacks are potentially important over polluted areas and should be taken into account in the development of emission control and climate mitigation policies for areas where the aerosol feedback signals are strong. PY - 2014/// DO - 10.1007/978-3-319-04379-1_10 SP - 61-66 OP - PB - Springer International Publishing SN - 9783319043784 9783319043791 UR - http://dx.doi.org/10.1007/978-3-319-04379-1_10 DB - Crossref ER - TY - RPRT TI - Establishment of Captive Populations of Magnificent Ramshorn (Planorbella magnifica) and Greenfield Ramshorn (Helisoma eucosmium) AU - Eads, C.B. AU - Levine, J.F. AU - Chestnutt, R.K. AU - Heinz, J. AU - Westmoreland, L. AU - Bloodgood, J. AU - Smith-Uhl, R. A3 - US Fish and Wildlife Service DA - 2014/// PY - 2014/// M3 - Final report PB - US Fish and Wildlife Service ER - TY - JOUR TI - Seasonal Changes in Microbial Community Structure in Freshwater Stream Sediment in a North Carolina River Basin AU - Bucci, John AU - Szempruch, Anthony AU - Caldwell, Jane AU - Ellis, Joseph AU - Levine, Jay T2 - Diversity AB - This study examined seasonal differences in microbial community structure in the sediment of three streams in North Carolina’s Neuse River Basin. Microbes that reside in sediment are at the base of the food chain and have a profound influence on the health of freshwater stream environments. Terminal-Restriction Fragment Length Polymorphism (T-RFLP), molecular fingerprint analysis of 16S rRNA genes was used to examine the diversity of bacterial species in stream sediment. Sediment was sampled in both wet and dry seasons from an agricultural (Bear), mixed urban (Crabtree) and forested (Marks) Creek, and the microbiota examined. Gamma, Alpha and Beta proteobacteria were prevalent species of microbial taxa represented among all sites. Actinobacteria was the next most prevalent species observed, with greater occurrence in dry compared to the wet season. Discernable clustering was observed of Marks and Bear Creek samples collected during the wetter period (September–April), which corresponded with a period of higher precipitation and cooler surface water temperatures. Although not statistically significant, microbial community structure appeared different between season (ANOSIM, R = 0.60; p < 0.10). Principal components analysis confirmed this pattern and showed that the bacterial groups were separated by wet and dry seasonal periods. These results suggest seasonal differences among the microbial community structure in sediment of freshwater streams and that these communities may respond to changes in precipitation during wetter periods. DA - 2014/1/3/ PY - 2014/1/3/ DO - 10.3390/d6010018 VL - 6 IS - 1 SP - 18-32 J2 - Diversity LA - en OP - SN - 1424-2818 UR - http://dx.doi.org/10.3390/d6010018 DB - Crossref ER - TY - RPRT TI - TNT Degradation by Natural Microbial Assemblages at Frontal Boundaries Between Water Masses in Coastal Ecosystems (ER-2124 interim report) AU - Montgomery, M.T. AU - Boyd, T.J. AU - Coffin, R.B. AU - Drake, L.A. AU - Hansen, L.T. AU - Osburn, C.L. A3 - Chemical Dynamics and Diagnostics Branch Naval Research Lab DA - 2014/// PY - 2014/// M1 - NRL/MR/6110--14-9552 M3 - Memorandum report PB - Chemical Dynamics and Diagnostics Branch Naval Research Lab SN - NRL/MR/6110--14-9552 ER - TY - RPRT TI - Measurement of Nitroaromatic Explosives by Micellar Electrokinetic Chromatography in Waters Collected Along a Tropical Estuary AU - Giordano, B.C. AU - Montgomery, M.T. AU - Osburn, C.L. AU - Lindsay, C. A3 - Chemical Dynamics and Diagnostics Branch, Naval Research Lab DA - 2014/// PY - 2014/// M1 - NRL/MR/6110--14-9504 M3 - Memorandum Report PB - Chemical Dynamics and Diagnostics Branch, Naval Research Lab SN - NRL/MR/6110--14-9504 UR - https://apps.dtic.mil/dtic/tr/fulltext/u2/a595043.pdf ER - TY - JOUR TI - Preface AU - Gao, Shu AU - Wang, Hou-jie AU - Liu, J. Paul T2 - Continental Shelf Research DA - 2014/11// PY - 2014/11// DO - 10.1016/J.CSR.2014.09.007 VL - 90 SP - 1 J2 - Continental Shelf Research LA - en OP - SN - 0278-4343 UR - http://dx.doi.org/10.1016/J.CSR.2014.09.007 DB - Crossref ER - TY - JOUR TI - Fluvial system development and subsequent marine transgression in Yellow River (Huanghe) delta and its adjacent sea regions during last glacial maximum to early Holocene AU - Zhou, Liangyong AU - Liu, Jian AU - Saito, Yoshiki AU - Liu, J. Paul AU - Li, Guangxue AU - Liu, Qingsong AU - Gao, Maosheng AU - Qiu, Jiandong T2 - Continental Shelf Research AB - Paleotopography of the Yellow River (Huanghe) delta area and the western Bohai Sea during the last glacial maximum (LGM) is important to understand fluvial activities of the Yellow River linked with the LGM climate. By integrating data sets of both onshore and offshore borehole cores and offshore high-resolution seismic profiles, we reconstructed the paleotopography of this area from the LGM to the early Holocene. The fluvial sediment facies of the LGM identified in these cores was characterized by poorly sorted medium- to coarse-grained sands, which shows chaotic patterns in seismic profiles. REE characteristics and clay mineral components of the fluvial sediments suggest that they were derived mostly from the paleo-Yellow River. The basal and top bounding surfaces of the fluvial sediments slope very gently toward the northeast, similar to the present morphology of the North China Plain formed by the Yellow River. No incised valley morphology is detected in the basal topography, because of the long distance from the study area to the paleoshoreline during the LGM, and also because of the very gentle gradient of the paleo-Yellow River from the northern part of North China Plain to the continental shelf area, with concave-upward morphology. Aggradational stacking of the fluvial sediments over the entire North China Plain and in the study area indicates that the Yellow River flowed in these areas during the LGM to the early Holocene. The Holocene marine and coastal sediments onlap onto the underlying fluvial sediments. These basal marine or brackish sediments are diachronous from offshore areas of the Bohai Sea to the Yellow River delta area, with older sediments in the east and younger sediments in the west, which clearly reflects the early Holocene marine transgression from the North Yellow Sea to the Bohai Sea. DA - 2014/11// PY - 2014/11// DO - 10.1016/J.CSR.2014.06.012 VL - 90 SP - 117-132 J2 - Continental Shelf Research LA - en OP - SN - 0278-4343 UR - http://dx.doi.org/10.1016/J.CSR.2014.06.012 DB - Crossref KW - Holocene transgression KW - Paleotopography KW - Fluvial sediment KW - Bohai Sea KW - North Yellow Sea KW - Yellow River delta ER - TY - JOUR TI - Control of river stage on the reactive chemistry of the hyporheic zone AU - Byrne, P. AU - Binley, A. AU - Heathwaite, A. L. AU - Ullah, S. AU - Heppell, C. M. AU - Lansdown, K. AU - Zhang, H. AU - Trimmer, M. AU - Keenan, P. T2 - Hydrological Processes AB - Abstract We examined the influence of river stage on subsurface hydrology and pore water chemistry within the hyporheic zone of a groundwater‐fed river during the summer baseflow period of 2011. We found river stage and geomorphologic environment to control chemical patterns in the hyporheic zone. At a high river stage, the flux of upwelling water in the shallow sediments (>20 cm) decreased at sample sites in the upper section of our study reach and increased substantially at sites in the lower section. This differential response is attributed to the contrasting geomorphology of these subreaches that affects the rate of the rise and fall of a river stage relative to the subsurface head. At sites where streamward vertical flux decreased, concentration profiles of a conservative environmental tracer suggest surface water infiltration into the riverbed below depths recorded at a low river stage. An increase in vertical flux at sites in the lower subreach is attributed to the movement of lateral subsurface waters originating from the adjacent floodplain. This lateral‐moving water preserved or decreased the vertical extent of the hyporheic mixing zone observed at a low river stage. Downwelling surface water appeared to be responsible for elevated dissolved organic carbon (DOC) and manganese (Mn) concentrations in shallow sediments (0–20 cm); however, lateral subsurface flows were probably important for elevated concentrations of these solutes at deeper levels. Results suggest that DOC delivered to hyporheic sediments during a high river stage from surface water and lateral subsurface sources could enhance heterotrophic microbial activities. Copyright © 2013 John Wiley & Sons, Ltd. DA - 2014/8/15/ PY - 2014/8/15/ DO - 10.1002/HYP.9981 VL - 28 IS - 17 SP - 4766–4779 SN - 0885-6087 UR - http://dx.doi.org/10.1002/HYP.9981 KW - hyporheic zone KW - river stage KW - pore water KW - nutrients KW - biogeochemistry KW - dissolved organic carbon ER - TY - JOUR TI - Seismic triggering induced by lithospheric flexure due to eustatic sea level rise | Sismicidade desencadeada em Portugal Continental por flexão litosférica associada a subida eustática do nível do mar T2 - Comunicacoes Geologicas DA - 2014/// PY - 2014/// UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84939799713&partnerID=MN8TOARS ER - TY - JOUR TI - Seismic triggering induced by lithospheric flexure due to eustatic sea level rise | Sismicidade desencadeada em Portugal Continental por flexão litosférica associada a subida eustática do nível do mar AU - Neves, M.C. AU - Cabral, J. AU - Figueiredo, P.M. AU - Sandwell, D. AU - Rockwell, T.K. AU - Luttrell, K. T2 - Comunicacoes Geologicas DA - 2014/// PY - 2014/// VL - 101 SP - 913-917 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84939799713&partnerID=MN8TOARS ER - TY - JOUR TI - Lower Palaeolithic artifacts from Plakias, Crete: Implications for Hominin Dispersals AU - Runnels, C. AU - DiGregorio, C. AU - Wegmann, K.W. AU - Gallen, S.F. AU - Strasser, T.F. AU - Panagopoulou, E. T2 - Eurasian Prehistory DA - 2014/// PY - 2014/// VL - v. 11 SP - 129–152 UR - https://www.peabody.harvard.edu/node/2543 ER - TY - JOUR TI - Active simultaneous uplift and margin-normal extension in a forearc high, Crete, Greece AU - Gallen, S.F. AU - Wegmann, K.W. AU - Bohnenstiehl, D.R. AU - Pazzaglia, F.J. AU - Brandon, M.T. AU - Fassoulas, C. T2 - Earth and Planetary Science Letters AB - The island of Crete occupies a forearc high in the central Hellenic subduction zone and is characterized by sustained exhumation, surface uplift and extension. The processes governing orogenesis and topographic development here remain poorly understood. Dramatic topographic relief (2–6km) astride the southern coastline of Crete is associated with large margin-parallel faults responsible for deep bathymetric depressions known as the Hellenic troughs. These structures have been interpreted as both active and inactive with either contractional, strike-slip, or extensional movement histories. Distinguishing between these different structural styles and kinematic histories here allows us to explore more general models for improving our global understanding of the tectonic and geodynamic processes of syn-convergent extension. We present new observations from the south–central coastline of Crete that clarifies the role of these faults in the late Cenozoic evolution of the central Hellenic margin and the processes controlling Quaternary surface uplift. Pleistocene marine terraces are used in conjunction with optically stimulated luminesce dating and correlation to the Quaternary eustatic curve to document coastal uplift and identify active faults. Two south-dipping normal faults are observed, which extend offshore, offset these marine terrace deposits and indicate active N–S (margin-normal) extension. Further, marine terraces preserved in the footwall and hanging wall of both faults demonstrate that regional net uplift of Crete is occurring despite active extension. Field mapping and geometric reconstructions of an active onshore normal fault reveal that the subaqueous range-front fault of south–central Crete is synthetic to the south-dipping normal faults on shore. These findings are inconsistent with models of active horizontal shortening in the upper crust of the Hellenic forearc. Rather, they are consistent with topographic growth of the forearc in a viscous orogenic wedge, where crustal thickening and uplift are a result of basal underplating of material that is accompanied by extension in the upper portions of the wedge. Within this framework a new conceptual model is presented for the late Cenozoic vertical tectonics of the Hellenic forearc. DA - 2014/// PY - 2014/// DO - http://dx.doi.org/10.1016/j.epsl.2014.04.038 VL - 398 IS - SP - 11 - 24 UR - http://www.sciencedirect.com/science/article/pii/S0012821X14002787 N1 - RN - ER - TY - JOUR TI - Multi-proxy evidence for tectonic control on the expansion of C4 grasses in northwest Argentina AU - Cotton, Jennifer M. AU - Hyland, Ethan G. AU - Sheldon, Nathan D. T2 - Earth and Planetary Science Letters AB - The timing of the rise of C4 grasses and the climatic conditions driving their expansion are widely debated, with recent studies suggesting that the expansion was more complex than previously thought. Proxy reconstructions from northwestern Argentina record multiple increases and decreases in C4 abundance throughout the late Miocene to early Pliocene, as well as variations in the timing of the spread of C4 grasses into the region. Here we present a multi-proxy paleovegetation reconstruction of the proportions of C3 and C4 vegetation using organic carbon and phytoliths preserved in paleosols at Entre Ríos in the Santa María Basin of Catamarca, Argentina between 6.2 and 3.3 Ma. Both δCorg13 and phytolith assemblages indicate a C3 dominated ecosystem with no evidence for substantial amounts of C4 vegetation from the late Miocene through mid-Pliocene, despite their rise to dominance elsewhere during this time. These data suggest that by 6.2 Ma the Santa María basin floor was at an elevation high enough to create locally cool conditions that allowed C3 vegetation to outcompete C4 grasses. Phytolith assemblages show that later uplift of the Sierra Calchaquies and Sierra Aconquija ranges through the Pliocene increased aridity and drove the expansion of C3 grasses at the expense of palms and other forest indicators. This multi-proxy paleovegetation reconstruction demonstrates that tectonics played an important role in controlling the late Miocene expansion C4 grasses by suppressing their spread into northwest Argentina. DA - 2014/6// PY - 2014/6// DO - 10.1016/J.EPSL.2014.03.014 VL - 395 SP - 41-50 J2 - Earth and Planetary Science Letters LA - en OP - SN - 0012-821X UR - http://dx.doi.org/10.1016/J.EPSL.2014.03.014 DB - Crossref KW - C-4 grasses KW - stable isotopes KW - phytoliths KW - Andes ER - TY - JOUR TI - Mercury’s global contraction much greater than earlier estimates AU - Byrne, Paul K. AU - Klimczak, Christian AU - Celâl Şengör, A. M. AU - Solomon, Sean C. AU - Watters, Thomas R. AU - Hauck, II, Steven A. T2 - Nature Geoscience DA - 2014/3/16/ PY - 2014/3/16/ DO - 10.1038/NGEO2097 VL - 7 IS - 4 SP - 301-307 J2 - Nature Geosci LA - en OP - SN - 1752-0894 1752-0908 UR - http://dx.doi.org/10.1038/NGEO2097 DB - Crossref ER - TY - JOUR TI - A new synoptic scale resolving global climate simulation using the Community Earth System Model AU - Small, R. Justin AU - Bacmeister, Julio AU - Bailey, David AU - Baker, Allison AU - Bishop, Stuart AU - Bryan, Frank AU - Caron, Julie AU - Dennis, John AU - Gent, Peter AU - Hsu, Hsiao‐ming AU - Jochum, Markus AU - Lawrence, David AU - Muñoz, Ernesto AU - diNezio, Pedro AU - Scheitlin, Tim AU - Tomas, Robert AU - Tribbia, Joseph AU - Tseng, Yu‐heng AU - Vertenstein, Mariana T2 - Journal of Advances in Modeling Earth Systems AB - Abstract High‐resolution global climate modeling holds the promise of capturing planetary‐scale climate modes and small‐scale (regional and sometimes extreme) features simultaneously, including their mutual interaction. This paper discusses a new state‐of‐the‐art high‐resolution Community Earth System Model (CESM) simulation that was performed with these goals in mind. The atmospheric component was at 0.25° grid spacing, and ocean component at 0.1°. One hundred years of “present‐day” simulation were completed. Major results were that annual mean sea surface temperature (SST) in the equatorial Pacific and El‐Niño Southern Oscillation variability were well simulated compared to standard resolution models. Tropical and southern Atlantic SST also had much reduced bias compared to previous versions of the model. In addition, the high resolution of the model enabled small‐scale features of the climate system to be represented, such as air‐sea interaction over ocean frontal zones, mesoscale systems generated by the Rockies, and Tropical Cyclones. Associated single component runs and standard resolution coupled runs are used to help attribute the strengths and weaknesses of the fully coupled run. The high‐resolution run employed 23,404 cores, costing 250 thousand processor‐hours per simulated year and made about two simulated years per day on the NCAR‐Wyoming supercomputer “Yellowstone.” DA - 2014/12// PY - 2014/12// DO - 10.1002/2014MS000363 VL - 6 IS - 4 SP - 1065-1094 J2 - J. Adv. Model. Earth Syst. LA - en OP - SN - 1942-2466 1942-2466 UR - http://dx.doi.org/10.1002/2014MS000363 DB - Crossref KW - carbon and nitrogen modeling KW - spin-up KW - steady state simulation KW - soil organic carbon KW - Community Land Model KW - NGBGC ER - TY - JOUR TI - High Relative Humidity as a Trigger for Widespread Release of Ice Nuclei AU - Wright, Timothy P. AU - Hader, John D. AU - McMeeking, Gavin R. AU - Petters, Markus D. T2 - Aerosol Science and Technology AB - Copyright 2014 American Association for Aerosol Research DA - 2014/10/15/ PY - 2014/10/15/ DO - 10.1080/02786826.2014.968244 VL - 48 IS - 11 SP - i-v J2 - Aerosol Science and Technology LA - en OP - SN - 0278-6826 1521-7388 UR - http://dx.doi.org/10.1080/02786826.2014.968244 DB - Crossref ER - TY - JOUR TI - Observational- and model-based trends and projections of extreme precipitation over the contiguous United States AU - Janssen, Emily AU - Wuebbles, Donald J. AU - Kunkel, Kenneth E. AU - Olsen, Seth C. AU - Goodman, Alex T2 - Earth's Future AB - Abstract Historical and projected trends in extreme precipitation events are examined in Coupled Model Intercomparison Project 5 ( CMIP5 ) models and observations, over the contiguous United States ( CONUS ), using several approaches. This study updates earlier studies that have used the extreme precipitation index ( EPI ) to assess observations and goes further by using the EPI to evaluate available climate model simulations. An increasing trend over the CONUS was found in the EPI , with large differences among seven subregions of the United States. Median of CMIP5 simulations also finds an increasing trend in the EPI , but with a smaller magnitude than the observations. Model spread is large and in most cases bigger than the model signal itself. Statistically significant (95th confidence level) increasing trends in the observational‐based EPI occur over the Midwest and Eastern regions, while most decreasing trends occur over Western regions. Some models give negative correlation coefficients relative to observations. However, some ensemble members, for most models, show correlation coefficients greater than 0.5. Projections of extreme precipitation event frequency, for representative concentration pathway ( RCP ) scenarios 4.5 and 8.5, show increasing trends over the CONUS . Both scenarios give a steady increase throughout the period but the RCP 4.5 signal is smaller in magnitude. Overall, the RCP scenarios show an increase across all regions with the exception of some variability between decades in some regions for RCP 4.5. For the CONUS model spread is smaller than the projected signal. Regional analyses show overall agreement among models of a future increase in extreme precipitation event frequency over most regions. DA - 2014/2// PY - 2014/2// DO - 10.1002/2013EF000185 VL - 2 IS - 2 SP - 99-113 J2 - Earth's Future LA - en OP - SN - 2328-4277 UR - http://dx.doi.org/10.1002/2013EF000185 DB - Crossref KW - Extreme Precipitation KW - CMIP5 ER - TY - JOUR TI - Measurements and analysis of air quality in Islamabad, Pakistan AU - Rasheed, Anjum AU - Aneja, Viney P. AU - Aiyyer, Anantha AU - Rafique, Uzaira T2 - Earth's Future AB - Abstract Ambient air quality of Islamabad, Pakistan, reveals that annual average mass concentration of particulate matter ( PM 2 .5 ) (∼45 to ∼95 µg m −3 ) and nitric oxide ( NO ) (∼41 to ∼120 µg m −3 ) exceeds the Pakistan's National Environmental Quality Standards ( NEQS ). The annual ozone ( O 3 ) concentration is within the permissible limits; however, some of the hourly concentration exceeds the NEQS mostly during the summer months. Correlation studies suggest that carbon monoxide ( CO ) has a significant ( p ‐value ≤ 0.01) positive correlation with NO and NO y′ ; whereas, with O 3 , a significant ( p ‐value ≤ 0.01) negative correlation is observed. The regression analysis estimates the background CO concentration to be ∼300 to ∼600 ppbv in Islamabad. The higher ratio of CO / NO (∼10) suggests that mobile sources are the major contributor to NO concentration. On the other hand, the ratio analysis of sulfur dioxide ( SO 2 )/ NO for Islamabad (∼0.011) indicates that the point sources are contributing to SO 2 in the city. NO and SO 2 correlation indicates contribution of direct sulfur emission sources. Ratios of [ CO ] to [ NO ] and [ SO 2 ] to [ NO ], based on ambient air quality measurements, provide a test for emission inventories. The ratios of these pollutants in the available Islamabad emission inventories are consistent with ambient values for these pollutants. The correlation of PM 2 .5 and NO suggests that a fraction of secondary PM 2 .5 is produced by chemical conversion of NO into nitrates. The regional background O 3 concentration for Islamabad has been determined to be ∼31 ppbv. This study suggests that there is an increase in O 3 concentration with increases in photochemical conversion of NO to reservoir NO y′ species. DA - 2014/6// PY - 2014/6// DO - 10.1002/2013EF000174 VL - 2 IS - 6 SP - 303-314 J2 - Earth's Future LA - en OP - SN - 2328-4277 UR - http://dx.doi.org/10.1002/2013EF000174 DB - Crossref KW - Ambient Air Quality KW - Criteria Pollutants KW - Urbanization KW - Industrial Development KW - Energy KW - Pakistan ER - TY - CHAP TI - Physicochemical Effects on Dissolved Organic Matter Fluorescence in Natural Waters AU - Osburn, Christopher L. AU - Del Vecchio, Rossana AU - Boyd, Thomas J. T2 - Aquatic Organic Matter Fluorescence A2 - Coble, Paula A2 - Lead, Jaimie A2 - Baker, Andy A2 - Reynolds, Darren M. A2 - Spencer, Robert G.M. PY - 2014/6/9/ DO - 10.1017/cbo9781139045452.012 SP - 233-277 OP - PB - Cambridge University Press SN - 9781139045452 UR - http://dx.doi.org/10.1017/cbo9781139045452.012 DB - Crossref ER - TY - JOUR TI - A microarray for assessing transcription from pelagic marine microbial taxa AU - Shilova, Irina N AU - Robidart, Julie C AU - James Tripp, H AU - Turk-Kubo, Kendra AU - Wawrik, Boris AU - Post, Anton F AU - Thompson, Anne W AU - Ward, Bess AU - Hollibaugh, James T AU - Millard, Andy AU - Ostrowski, Martin AU - J Scanlan, David AU - Paerl, Ryan W AU - Stuart, Rhona AU - Zehr, Jonathan P T2 - The ISME Journal AB - Metagenomic approaches have revealed unprecedented genetic diversity within microbial communities across vast expanses of the world's oceans. Linking this genetic diversity with key metabolic and cellular activities of microbial assemblages is a fundamental challenge. Here we report on a collaborative effort to design MicroTOOLs (Microbiological Targets for Ocean Observing Laboratories), a high-density oligonucleotide microarray that targets functional genes of diverse taxa in pelagic and coastal marine microbial communities. MicroTOOLs integrates nucleotide sequence information from disparate data types: genomes, PCR-amplicons, metagenomes, and metatranscriptomes. It targets 19 400 unique sequences over 145 different genes that are relevant to stress responses and microbial metabolism across the three domains of life and viruses. MicroTOOLs was used in a proof-of-concept experiment that compared the functional responses of microbial communities following Fe and P enrichments of surface water samples from the North Pacific Subtropical Gyre. We detected transcription of 68% of the gene targets across major taxonomic groups, and the pattern of transcription indicated relief from Fe limitation and transition to N limitation in some taxa. Prochlorococcus (eHLI), Synechococcus (sub-cluster 5.3) and Alphaproteobacteria SAR11 clade (HIMB59) showed the strongest responses to the Fe enrichment. In addition, members of uncharacterized lineages also responded. The MicroTOOLs microarray provides a robust tool for comprehensive characterization of major functional groups of microbes in the open ocean, and the design can be easily amended for specific environments and research questions. DA - 2014/1/30/ PY - 2014/1/30/ DO - 10.1038/ismej.2014.1 VL - 8 IS - 7 SP - 1476-1491 J2 - ISME J LA - en OP - SN - 1751-7362 1751-7370 UR - http://dx.doi.org/10.1038/ismej.2014.1 DB - Crossref KW - marine KW - microbial KW - microarray KW - transcription KW - molecular ER - TY - JOUR TI - Gammaproteobacterial diazotrophs and nifH gene expression in surface waters of the South Pacific Ocean AU - Moisander, Pia H AU - Serros, Tracy AU - Paerl, Ryan W AU - Beinart, Roxanne A AU - Zehr, Jonathan P T2 - The ISME Journal AB - In addition to the cyanobacterial N2-fixers (diazotrophs), there is a high nifH gene diversity of non-cyanobacterial groups present in marine environments, yet quantitative information about these groups is scarce. N2 fixation potential (nifH gene expression), diversity and distributions of the uncultivated diazotroph phylotype γ-24774A11, a putative gammaproteobacterium, were investigated in the western South Pacific Ocean. γ-24774A11 gene copies correlated positively with diazotrophic cyanobacteria, temperature, dissolved organic carbon and ambient O2 saturation, and negatively with depth, chlorophyll a and nutrients, suggesting that carbon supply, access to light or inhibitory effects of DIN may control γ-24774A11 abundances. Maximum nifH gene-copy abundance was 2 × 10(4) l(-1), two orders of magnitude less than that for diazotrophic cyanobacteria, while the median γ-24774A11 abundance, 8 × 10(2) l(-1), was greater than that for the UCYN-A cyanobacteria, suggesting a more homogeneous distribution in surface waters. The abundance of nifH transcripts by γ-24774A11 was greater during the night than during the day, and the transcripts generally ranged from 0-7%, but were up to 26% of all nifH transcripts at each station. The ubiquitous presence and low variability of γ-24774A11 abundances across tropical and subtropical oceans, combined with the consistent nifH expression reported in this study, suggest that γ-24774A11 could be one of the most important heterotrophic (or photoheterotrophic) diazotrophs and may need to be considered in future N budget estimates and models. DA - 2014/4/10/ PY - 2014/4/10/ DO - 10.1038/ismej.2014.49 VL - 8 IS - 10 SP - 1962-1973 J2 - ISME J LA - en OP - SN - 1751-7362 1751-7370 UR - http://dx.doi.org/10.1038/ismej.2014.49 DB - Crossref KW - Crocosphaera KW - diel cycle KW - nifH KW - nitrogen cycle KW - transcription KW - UCYN-A ER - TY - JOUR TI - Quantifying environmental stress induced emissions of algal isoprene and monoterpenes using laboratory measurements AU - Meskhidze, N. AU - Sabolis, A. AU - Reed, R. AU - Kamykowski, D. T2 - Biogeosciences Discussions AB - Abstract. We report here production rates of isoprene and monoterpene compounds (α-pinene, β-pinene, camphene and d-limonene) from six phytoplankton monocultures as a function of irradiance and temperature. Irradiance experiments were carried out for diatom strains – Thalassiosira weissflogii and Thalassiosira pseudonana; prymnesiophyte strains – Pleurochrysis carterae; dinoflagellate strains – Karenia brevis and Prorocentrum minimum; cryptophyte strains – Rhodomonas salina, while temperature experiments were carried out for diatom strains – Thalassiosira weissflogii and Thalassiosira pseudonana. Phytoplankton species, incubated in a climate-controlled room, were subject to variable light (90 to 900 μmol m−2s−1) and temperature (18 to 30 °C) regimes. Compared to isoprene, monoterpene emissions were an order of magnitude lower at all light and temperature levels. Emission rates are normalized by cell count and Chlorophyll a (Chl a) content. Diatom strains were the largest emitters, with ~2x1017g (cell)−1h−1 (~35 μg (g Chl a)−1h−1) for isoprene and ~5x10−19 g (cell)−1h−1 (~1μg (g Chl a)−1) h−1) for α-pinene. The contribution to the total monoterpene production was ~70% from α-pinene, ~20% for d-limonene, and <10% for camphene and β -pinene. Phytoplankton species showed a rapid increase in production rates at low (<150 μmol m−2s−1) and a gradual increase at high (>250 μmol m−2s−1) irradiance. Measurements revealed different patterns for time-averaged emissions rates over two successive days. On the first day most of the species showed distinct increase in production rates within the first four hours, while on the second day the emission rates were overall higher, but less variable. The data suggest that enhanced amounts of isoprene and monoterpenes are emitted from phytoplankton as a result of perturbations in environmental conditions that cause disbalance in chloroplasts and forces primary producers to acclimate physiologically. This relationship could be a valuable tool for development of dynamic ecosystem modeling approaches for global marine isoprene and monoterpene emissions based on phytoplankton physiological responses to a changing environment. DA - 2014/9/19/ PY - 2014/9/19/ DO - 10.5194/bgd-11-13533-2014 VL - 11 IS - 9 SP - 13533-13570 J2 - Biogeosciences Discuss. LA - en OP - SN - 1810-6285 UR - http://dx.doi.org/10.5194/bgd-11-13533-2014 DB - Crossref ER - TY - CHAP TI - Examining Material Transport in Dynamic Coastal Environments: An Integrated Approach Using Field Data, Remote Sensing and Numerical Modeling AU - Miller, Richard L. AU - López, Ramón AU - Mulligan, Ryan P. AU - Reed, Robert E. AU - Liu, Cheng-Chien AU - Buonassissi, Christopher J. AU - Brown, Matthew M. T2 - Remote Sensing and Modeling AB - Coastal environments are critical ecological systems and offer vital resources and functions to societies worldwide. As a major interface between terrestrial and ocean environments, coastal water bodies (rivers, estuaries, bays and coastal margins) provide key ecological services and are the major conduit and processors of terrestrially derived particulate and dissolved material as they are transported to the ocean. Consequently, coastal environments have been shown to play a major role in global bio-geochemical cycles and provide critical habitat for a host of marine species. Globally, these important environments are under considerable pressure from high population densities, increasing growth rates and are particularly vulnerable from the effects of projected climate change such as sea level rise and increased storm events. Despite their importance, significant gaps remain in our understanding of how these environments will respond to climate change, increasing human population, land use changes, and over exploitation of natural resources. This lack of understanding is due in part to the difficulties in developing effective monitoring and analysis programs using only a single measurement approach that is limited in its spatial and temporal coverage. We describe an integrated approach based on field measurements, remote sensing and numerical modeling that is being developed to examine the transport of dissolved (colored dissolved organic matter (CDOM), dissolved organic carbon (DOC)) and particulate material (total suspended matter (TSM)) within a complex coastal system, the Albemarle-Pamlico Estuarine System (APES), North Carolina USA. This integrated approach was established to overcome limitations associated with a single measurement and analysis approach. Field measurements and discrete samples are acquired using well-established protocols from small boats, bridges, and from the shore. Remotely sensed data are obtained from several sensors with diverse capabilities including SeaWiFS, MODIS, MERIS, HICO, Landsat and FORMOSAT-2. The numerical model Delft3D is used to simulate freshwater and DOC transport in the estuaries following major rainfall events that lead to high river discharge. Challenges associated with examining the APES using a single vs. an integrated measurement approach along with representative results from a broad suite of measurements are presented. Future advances in technology and refinements in our integrated approach are also considered. PY - 2014/// DO - 10.1007/978-3-319-06326-3_14 SP - 333-364 OP - PB - Springer International Publishing SN - 9783319063256 9783319063263 UR - http://dx.doi.org/10.1007/978-3-319-06326-3_14 DB - Crossref ER - TY - JOUR TI - Regional Climate Variations and Change for Terrestrial Ecosystems Workshop Review T2 - Bulletin of the Ecological Society of America AB - North Carolina State University, the University of North Carolina at Chapel Hill, and the U.S. Environmental Protection Agency, in partnership with the U.S. Department of the Interior Southeast Climate Science Center (SECSC), hosted the Regional Climate Variations and Change for Terrestrial Ecosystems Workshop. The workshop was held at North Carolina State University in Raleigh on 16–17 May 2013. The workshop assembled ~40 climate and ecosystem scientists to discuss challenges and uncertainties of understanding the interactions of climate and ecosystems across the Carolinas. This multidisciplinary effort sought to bridge the knowledge gap between climate and ecosystems scientists. Another objective of this workshop was to identify climate-related variables that can be used to evaluate projections of climate change for the ecology community in the Carolinas. This workshop was the first in the Carolinas to engage both disciplines to discuss the needs of the ecology community with regard to regional projections of climate change. The workshop facilitated a discussion of the needs of ecologists from the regional projections of climate change, and the abilities and limitations of these projections, with guidance for appropriate use of projection information. High-level scientific presentations were given from the two disciplines to create a foundation for discussion. Climate presentations focused on data needs for ecosystem scientists and included talks on global climate modeling, dynamical and statistical downscaling, and synthesizing currently available climate change projections. The open discussion on climate model data sets provided expert guidance on using climate change projections for ecosystems applications. The ecologists' presentations focused on ecosystems needs and challenges, including different ecosystems modeling techniques, uncertainties associated with ecosystem modeling, and examples of climate adaptation practices for ecosystem decisions with respect to climate change. The final discussion addressed the general needs of ecologists with regard to climate information, followed by the climate sensitivities that are drivers for ecological applications in the Southeast. During the discussion, ecologists identified that extreme weather events and potential changes to the spatial and temporal distribution of those events are important for ecosystems. The extremes mentioned most often by the group included temperature extremes, rainfall extremes, and storm frequency. Ecologists also identified that the downscaling does not provide the resolution needed for many applications, and interpolation is typically used to supplement downscaled data. For instance, topoclimatic models are applied to increase the resolution of downscaled climate change data sets. However, climate scientists stress that these techniques are not appropriate for extremes or spatially discontinuous variables such as precipitation. More solicitations on collaborative research between ecosystems scientists and climate modelers on discrete decision-based projects are encouraged. More documentation and guidance from the climate science community regarding: Appropriate use of downscaled climate change data sets, including strengths and weaknesses Error and uncertainty propagation in climate modeling Integrating climate data with land use change information. Further engagement is encouraged between the ecologists, hydrologists, biologists, managers, and climate scientists through similar workshops held at least annually. It was acknowledged that some applications cannot use a small-project, decision-based approach; rather they require immediate action to integrate climate change information. In those instances, decision makers rely on the best available data for decisions, which further emphasizes need to document the strengths and weaknesses of climate data and provide expert guidance. As recommended, follow-on workshops will provide updates on the states of the scientific fields alongside discussions of priority needs. An in-depth summary of this workshop will become available through SECSC and the U.S. Geological Survey in early 2014, as part of an open technical report currently in review. That report will include the summary and guidance for the appropriate use based on comparisons of six publicly available regional climate data sets. DA - 2014/1// PY - 2014/1// DO - 10.1890/0012-9623-95.1.96 UR - http://dx.doi.org/10.1890/0012-9623-95.1.96 ER - TY - JOUR TI - Improving the representation of clouds, radiation, and precipitation using spectral nudging in the Weather Research and Forecasting model T2 - Journal of Geophysical Research: Atmospheres AB - Spectral nudging—a scale-selective interior constraint technique—is commonly used in regional climate models to maintain consistency with large-scale forcing while permitting mesoscale features to develop in the downscaled simulations. Several studies have demonstrated that spectral nudging improves the representation of regional climate in reanalysis-forced simulations compared with not using nudging in the interior of the domain. However, in the Weather Research and Forecasting (WRF) model, spectral nudging tends to produce degraded precipitation simulations when compared to analysis nudging—an interior constraint technique that is scale indiscriminate but also operates on moisture fields which until now could not be altered directly by spectral nudging. Since analysis nudging is less desirable for regional climate modeling because it dampens fine-scale variability, changes are proposed to the spectral nudging methodology to capitalize on differences between the nudging techniques and aim to improve the representation of clouds, radiation, and precipitation without compromising other fields. These changes include adding spectral nudging toward moisture, limiting nudging to below the tropopause, and increasing the nudging time scale for potential temperature, all of which collectively improve the representation of mean and extreme precipitation, 2 m temperature, clouds, and radiation, as demonstrated using a model-simulated 20 year historical period. Such improvements to WRF may increase the fidelity of regional climate data used to assess the potential impacts of climate change on human health and the environment and aid in climate change mitigation and adaptation studies. DA - 2014/10/27/ PY - 2014/10/27/ DO - 10.1002/2014jd022173 UR - http://dx.doi.org/10.1002/2014jd022173 KW - regional climate modeling KW - spectral nudging KW - downscaling KW - WRF ER - TY - CONF TI - GIS-based environmental modeling with tangible interaction and dynamic visualization AU - Petrasova, A. AU - Harmon, B. AU - Petras, V. AU - Mitasova, H. C2 - 2014/// C3 - Proceedings - 7th International Congress on Environmental Modelling and Software: Bold Visions for Environmental Modeling, iEMSs 2014 DA - 2014/// VL - 2 SP - 758-765 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84911897646&partnerID=MN8TOARS ER - TY - JOUR TI - Barrier island dynamics using mass center analysis: A new way to detect and track large-scale change AU - Paris, P. AU - Mitasova, H. T2 - ISPRS International Journal of Geo-Information AB - A geographic information system (GIS) was used to introduce and test a new method for quantitatively characterizing topographic change. Borrowing from classic Newtonian mechanics, the concept of a body’s center of mass is applied to the geomorphic landscape, and the barrier island environment in particular, to evaluate the metric’s potential as a proxy for detecting, tracking and visualizing change. Two barrier islands along North Carolina’s Outer Banks are used to test this idea: Core Banks, uninhabited and largely-undeveloped, and Hatteras Island, altered by the presence of a protective dune system. Findings indicate that for Core Banks, the alongshore change in the center of mass is in accord with dominate littoral transport and wind conditions. Cross-shore change agrees with independent estimates for the island migration rates. This lends credence to our assertion that the mass center metric has the potential to be a viable proxy for describing wholesale barrier migration and would be a valuable addition to the already-established ocean shoreline and subaerial volume metrics. More research is, however, required to demonstrate efficacy. DA - 2014/// PY - 2014/// DO - 10.3390/ijgi3010049 VL - 3 IS - 1 SP - 49-65 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84948740266&partnerID=MN8TOARS KW - barrier islands KW - center of mass KW - geomorphology KW - geographic information systems (GISs) KW - GRASS KW - QGIS ER - TY - JOUR TI - Mesoscale Modeling of Low-Level Jets over the North Sea AU - Nunalee, Christopher AU - Basu, Sukanta T2 - WIND ENERGY - IMPACT OF TURBULENCE AB - Contemporary onshore and offshore wind resource assessment frameworks incorporate diverse multi-scale weather predictionmodels (commonly known as mesoscale models) to dynamically downscale global-scale atmospheric fields to regional-scale (i.e., spatial and temporal resolutions of a few kilometers and a few minutes, respectively). These high resolution mesoscale models aim at depicting the expected wind behavior (e.g., wind shear, wind turning, topographically induced flow accelerations) at a particular location or region. Over the years, numerous model sensitivity and intercomparison studies have investigated the strengths and weaknesses of the models’ parameterizations (including, but not limited to, planetary boundary layer turbulence) in capturing realistic flows over land. In contrast, only a handful of modeling studies have focused on coastal and offshore flows (e.g., coastal fronts, internal boundary layers, land breeze - sea breeze circulations, low level jets); thus, our understanding and predictive capability of these flows remain less than desirable. This impairment, in combination with the recent world-wide surge in offshore wind energy development, provides the rationale for this study. We are currently evaluating the performance of the Weather Research and Forecasting (WRF) model, a new-generation mesoscale model, in simulating some of the aforementioned coastal and offshore flow phenomena. In this paper, we focus on low-level jets and compare the WRF model-simulated results against the observational data from the FINO1 meteorological mast in the North Sea.We also discuss the sensitivities of the WRF model-generated offshore wind fields with respect to several planetary boundary layer turbulence schemes. DA - 2014/// PY - 2014/// DO - 10.1007/978-3-642-54696-9_29 VL - 2 SP - 197-202 SN - 2196-7806 ER - TY - JOUR TI - Developing the capacity to monitor climate change impacts in Mediterranean estuaries AU - Ustin, S. L. AU - Santos, M. J. AU - Hestir, E. L. AU - Khanna, S. AU - Casas, A. AU - Greenberg, J. T2 - Evolutionary Ecology Research DA - 2014/// PY - 2014/// VL - 16 IS - 6 SP - 529-550 ER - TY - JOUR TI - Circulation and cross-shelf transport in the Florida Big Bend AU - Todd, A. C. AU - Morey, S. L. AU - Chassignet, E. P. T2 - Journal of Marine Research DA - 2014/// PY - 2014/// VL - 72 IS - 6 SP - 445-475 ER - TY - JOUR TI - Tropical to extratropical: Marine environmental changes associated with Superstorm Sandy prior to its landfall AU - Zambon, Joseph B. AU - He, Ruoying AU - Warner, John C. T2 - Geophysical Research Letters AB - Abstract Superstorm Sandy was a massive storm that impacted the U.S. East Coast on 22–31 October 2012, generating large waves, record storm surges, and major damage. The Coupled Ocean‐Atmosphere‐Wave‐Sediment Transport modeling system was applied to hindcast this storm. Sensitivity experiments with increasing complexity of air‐sea‐wave coupling were used to depict characteristics of this immense storm as it underwent tropical to extratropical transition. Regardless of coupling complexity, model‐simulated tracks were all similar to the observations, suggesting the storm track was largely determined by large‐scale synoptic atmospheric circulation, rather than by local processes resolved through model coupling. Analyses of the sea surface temperature, ocean heat content, and upper atmospheric shear parameters showed that as a result of the extratropical transition and despite the storm encountering much cooler shelf water, its intensity and strength were not significantly impacted. Ocean coupling was not as important as originally thought for Sandy. DA - 2014/12/16/ PY - 2014/12/16/ DO - 10.1002/2014gl061357 VL - 41 IS - 24 SP - 8935-8943 J2 - Geophys. Res. Lett. LA - en OP - SN - 0094-8276 UR - http://dx.doi.org/10.1002/2014GL061357 DB - Crossref KW - Hurricane Sandy KW - landfall KW - air-sea-wave coupling ER - TY - JOUR TI - Generation of an S(alpha, beta) Covariance Matrix by Monte Carlo Sampling of the Phonon Frequency Spectrum AU - Holmes, J. C. AU - Hawari, A. I. T2 - NUCLEAR DATA SHEETS AB - Formats and procedures are currently established for representing covariances in the ENDF library for many reaction types. However, no standard exists for thermal neutron inelastic scattering cross section covariance data. These cross sections depend on the material's dynamic structure factor, or S ( α , β ) . The structure factor is a function of the phonon density of states (DOS). Published ENDF thermal neutron scattering libraries are commonly produced by modeling codes, such as NJOY/LEAPR, which utilize the DOS as the fundamental input and directly output the S ( α , β ) matrix. To calculate covariances for the computed S ( α , β ) data, information about uncertainties in the DOS is required. The DOS may be viewed as a probability distribution function of available atomic vibrational energy states in a solid. In this work, density functional theory and lattice dynamics in the harmonic approximation were used to simulate the structure of silicon dioxide ( α -quartz) to produce the DOS. A range for the variation in the partial DOS for silicon in α -quartz was established based on limits of variation in the crystal lattice parameters. Uncertainty in an experimentally derived DOS may also be incorporated with the same methodology. A description of possible variation in the DOS allowed Monte Carlo generation of a set of perturbed DOS spectra which were sampled to produce the S ( α , β ) covariance matrix for scattering with silicon in α -quartz. With appropriate sensitivity matrices, it is shown that the S ( α , β ) covariance matrix can be propagated to generate covariance matrices for integrated cross sections, secondary energy distributions, and coupled energy-angle distributions. DA - 2014/4// PY - 2014/4// DO - 10.1016/j.nds.2014.04.089 VL - 118 SP - 392-395 SN - 1095-9904 ER - TY - JOUR TI - Special issue sediment dynamics and related biogeochemical effects in the Eastern China shelf seas preface AU - Gao, S. AU - Wang, H. J. AU - Liu, J. P. T2 - Continental Shelf Research DA - 2014/// PY - 2014/// VL - 90 SP - 1-1 ER - TY - JOUR TI - Seasonal distribution of suspended sediment in the Bohai Sea, China AU - Wang, Houjie AU - Wang, Aimei AU - Bi, Naishuang AU - Zeng, Xiangming AU - Xiao, Hehui T2 - CONTINENTAL SHELF RESEARCH AB - Distribution of suspended sediment in the Bohai Sea and its seasonal variability were investigated based on the datasets obtained from four cruises carried out in different seasons in 2010 and 2012. The results indicate that the spatial distribution of suspended sediment in the Bohai Sea was dominated by the river input and coastal resuspension that depends on the type of local surface sediment and hydrodynamics. The suspended sediment was mostly concentrated in the southern Bohai Sea particularly around the Yellow River Delta in the summer season as impacted by the river plume but confined within a very limited area near the river mouth, whereas in winter–spring seasons sediment concentration became much higher as a result of active coastal resuspension induced by energetic wave actions in the shallow water. High sediment concentration was found in Liaodong Bay in winter–spring seasons when dynamics become strong but decrease significantly in summer seasons. The sediment concentration in the southern Bohai Strait was much higher than that in the northern part, suggesting evident sediment export to the Yellow Sea particularly in the winter–spring seasons. Strong seasonal variability of suspended sediment distribution in the Bohai Sea was consistent with the monsoon activity and associated wave actions and coastal currents that are varying seasonally. The dominance of seasonal monsoon signal and associated wave dynamics make the subaqueous Yellow River delta to be a major sink for the terrestrial sediment in the summer seasons, but transiting to a primary source in winter–spring seasons for sediment redistribution in the Bohai Sea and sediment export to the Yellow Sea. The seasonal patterns of suspended sediment distribution in the Bohai Sea and the dominance of monsoon activities may provide a good reference to understanding the sediment transport in the China Shelf Seas where sediment resuspension and coastal circulation are evidently driven by monsoon. DA - 2014/11/1/ PY - 2014/11/1/ DO - 10.1016/j.csr.2014.03.006 VL - 90 SP - 17-32 SN - 1873-6955 KW - Bohai Sea KW - Suspended sediment transport KW - Seasonal variability KW - Monsoon dominance KW - Wave actions ER - TY - JOUR TI - Measurement of atmospheric oxygen using long-path supercontinuum absorption spectroscopy AU - Brown, David M. AU - Brown, Andrea M. AU - Edwards, Perry S. AU - Liu, Zhiwen AU - Philbrick, C. Russell T2 - JOURNAL OF APPLIED REMOTE SENSING AB - The concentration of atmospheric oxygen is measured over a 540-m path using supercontinuum absorption spectroscopy. The absorption data compared favorably with MODTRAN™ 5 simulations of the spectra after adjusting for the differences of index of refraction of air and matching the instrument spectral resolution, as described by the effective slit width. Good agreement with the expected atmospheric oxygen concentration is obtained using a previously developed multiwavelength maximum likelihood estimation inversion algorithm. This study demonstrates the use of the SAS technique for measuring concentrations of chemical species with fine absorption structure on long-atmospheric paths. DA - 2014/9/3/ PY - 2014/9/3/ DO - 10.1117/1.jrs.8.083557 VL - 8 SP - SN - 1931-3195 KW - atmospheric species concentrations KW - supercontinuum laser KW - atmospheric differential absorption KW - differential absorption lidar KW - remote sensing ER - TY - JOUR TI - Fluvial system development and subsequent marine transgression in Yellow River (Huanghe) delta and its adjacent sea regions during last glacial maximum to early Holocene AU - Zhou, L. Y. AU - Liu, J. AU - Saito, Y. AU - Liu, J. P. AU - Li, G. X. AU - Liu, Q. S. AU - Gao, M. S. AU - Qiu, J. D. T2 - Continental Shelf Research DA - 2014/// PY - 2014/// VL - 90 SP - 117-132 ER - TY - JOUR TI - OYSTER-SPONGE INTERACTIONS AND BIOEROSION OF REEF-BUILDING SUBSTRATE MATERIALS: IMPLICATIONS FOR OYSTER RESTORATION AU - Dunn, Robert P. AU - Eggleston, David B. AU - Lindquist, Niels T2 - JOURNAL OF SHELLFISH RESEARCH AB - Subtidal oyster (Crassostrea virginica) reefs constructed during in the mid 1990s in Pamlico Sound, North Carolina, initially supported high densities of oysters; however, beginning around 2007, oyster density subsequently declined. Concurrent with the decline in oyster density was an increase in the prevalence of boring sponges (Cliona) on oysters and the underlying reef substrate material at these sites. The limestone marl substrate used to build these reefs became colonized by boring sponge to the degree that bioerosion by sponge potentially compromised the suitability of the reefs for oysters. Laboratory and field experiments were conducted to determine whether oyster demographic rates of settlement, recruitment, growth, and mortality were affected by the presence of Cliona on underlying shell substrate. Oyster settlement on shells with varying levels of sponge was measured in the laboratory, and oyster recruitment, growth, and mortality in the presence and absence of sponge were measured in 2 estuaries in coastal North Carolina from 2011 to 2012. Potential alternative substrates for future reef restoration were tested in the field to determine their susceptibility to bioerosion by sponges. Substrates included 2 composed of calcium carbonate (CaCO3; oyster shells and limestone marl) and 2 non-CaCO3 substrates (concrete and granite), because bioerosion by clionids target CaCO3. Surprisingly, no differences in oyster settlement, recruitment, growth, or mortality in the presence versus absence of Cliona were observed, suggesting that effects of the presence of sponge on oysters are either chronic rather than acute or are indirect and must act in concert with other oyster enemies. Notable patterns of sponge growth on the alternate substrates emerged; oyster shells were most susceptible to sponge growth, followed by marl, whereas concrete and granite were not susceptible to colonization by Cliona. Results from this study demonstrate the importance of having a strong understanding of the specific restoration methodology to be implemented, because the susceptibility of a substrate to bioerosion could have serious implications for reef longevity. Evidence is presented that consideration of the broader estuarine environment, including both biotic and abiotic factors, is vital when planning restoration actions, because the presence of Cliona was less important than the estuarine salinity gradient in altering oyster demographic rates and may shift the trajectories of restored reefs. DA - 2014/11// PY - 2014/11// DO - 10.2983/035.033.0307 VL - 33 IS - 3 SP - 727-738 SN - 1943-6319 KW - oyster KW - Crassostrea virginica KW - restoration KW - clionid sponge KW - salinity KW - bioerosion KW - settlement KW - recruitment KW - growth KW - mortality ER - TY - JOUR TI - Biogeochemical alteration of dissolved organic material in the Cape Fear River Estuary as a function of freshwater discharge AU - Dixon, J. L. AU - Helms, J. R. AU - Kieber, R. J. AU - Avery, G. B. T2 - Estuarine, Coastal and Shelf Science DA - 2014/// PY - 2014/// VL - 149 SP - 273-282 ER - TY - JOUR TI - Taconic Metamorphism Preserved in the Baie Verte Peninsula, Newfoundland Appalachians: Geochronological Evidence for Ophiolite Obduction and Subduction and Exhumation of the Leading Edge of the Laurentian (Humber) Margin During Closure of the Taconic Seaway AU - Castonguay, Sebastien AU - Staal, Cees R. AU - Joyce, Nancy AU - Skulski, Thomas AU - Hibbard, James P. T2 - GEOSCIENCE CANADA AB - The Baie Verte Peninsula, western Newfoundland Appalachians, preserves evidence for Early to Mid Ordovician closure of the Taconic seaway, which led to obduction of the Baie Verte oceanic tract (BVOT) ophiolites onto the Laurentian (Humber) margin and Taconic orogenesis. The scarcity of Taconic radiometric ages (and predominance of Silurian (Salinic) data) from the Humber margin rocks (down-going plate) has been problematic, calling into question the intensity and existence of Taconic collisional orogenesis. 40Ar/39Ar and in situ U–Pb geochronology was undertaken on metamorphosed units from the Laurentian basement (Mesoproterozoic East Pond Metamorphic Suite), from the ca. 560 Ma Birchy Complex forming the leading edge of the Humber margin, and from the ca. 490 Ma ophiolitic rocks of the BVOT (Advocate Complex) in order to address this question. Our results confirm evidence of Taconic metamorphism along the Humber margin and at the base of the ophiolites. Ages obtained from the structural base of the Advocate Complex (481–465 Ma) are interpreted to reflect the timing of accretion and internal thickening of the ophiolite, whereas data from the underlying Birchy Complex (467–461 Ma) record the underthrusting and exhumation of the leading edge of the Humber margin along a subduction channel, penecontemporaneously with final obduction of the BVOT. A concordant ca. 465 Ma zircon age and REE data obtained from retrogressed eclogite of the East Pond Metamorphic Suite suggest that the parautochthonous Humber margin was locally subducted to eclogite-facies conditions during the Taconic collision and partly exhumed to amphibolite-facies conditions prior to a strong Silurian (Salinic) tectonometamorphic overprint.SOMMAIRELa péninsule de Baie Verte dans les Appalaches de l’ouest de Terre-Neuve a conservé des indices de la fermeture du bras de mer taconique, qui a mené à l’obduction des ophiolites de la bande océanique de Baie Verte (BOBV) sur la marge laurentienne (Humber) et à l’orogénèse taconique. La rareté des âges radiométriques taconiques (et la prédominance des données siluriennes (saliniques)) provenant des roches de la marge de Humber (i.e. la plaque subductée) a été problématique, mettant en question l’intensité et l’existence de la collision orogénique taconique. De la géochronologie 40Ar/39Ar et U–Pb in situ a été réalisée sur des unités métamorphisés provenant du socle laurentien (la Suite Métamorphique d’East Pond d’âge Mésoprotérozoïque), du Complexe de Birchy daté à ca. 560 Ma formant la partie frontale de la marge de Humber, and des roches ophiolitiques de la BOBV (Complexe d’Advocate) datée à ca. 490 Ma afin de confronter ce questionnement. Nos résultats confirment les indices de métamorphisme taconique le long de la marge de Humber et à la base des ophiolites. Les âges obtenus à la base structurale du Complexe d’Advocate (481–465 Ma) sont interprétés comme reflétant la période d’accrétion et d’épaississement interne de l’ophiolite, tandis que les données du Complexe de Birchy sous-jacent (467–461 Ma) enregistrent le sous-charriage et l’exhumation de la partie frontale de la marge de Humber au sein d’un chenal de subduction, de façon pénécontemporaine à l’obduction finale de la BOBV. Un âge concordant de ca. 465 Ma d’un zircon et les données de terres rares provenant d’une éclogite rétromorphosée de la suite métamorphique d’East Pond suggèrent que la marge de Humber parautochtone a été localement subductée à des conditions du faciès éclogitique durant la collision taconique et partiellement exhumée à des conditions du faciès des amphibolites précédant la forte surimposition tectonométamorphique silurienne (salinique). DA - 2014/// PY - 2014/// DO - 10.12789/geocanj.2014.41.055 VL - 41 SP - 459-482 SN - 1911-4850 ER - TY - JOUR TI - Seasonal changes in estuarine dissolved organic matter due to variable flushing time and wind-driven mixing events AU - Dixon, Jennifer L. AU - Osburn, Christopher L. AU - Paerl, Hans W. AU - Peierls, Benjamin L. T2 - ESTUARINE COASTAL AND SHELF SCIENCE AB - This study examined the seasonality of dissolved organic matter (DOM) sources and transformations within the Neuse River estuary (NRE) in eastern North Carolina between March 2010 and February 2011. During this time, monthly surface and bottom water samples were collected along the longitudinal axis of the NRE, ranging from freshwater to mesohaline segments. The monthly mean of all surface and bottom measurements made on collected samples was used to clarify larger physical mixing controls in the estuary as a whole. By comparing monthly mean trends in DOM and chromophoric dissolved organic matter (CDOM) properties in surface and bottom waters during varying hydrological conditions, we found that DOM and CDOM quality in the NRE is controlled by a combination of discharge, wind speed, and wind direction. The quality of DOM was assessed using C:N ratios, specific ultraviolet absorption at 254 nm (SUVA254), the absorption spectral slope ratio (SR), and the humification (HIX) and biological (BIX) indices from fluorescence. The NRE reflects allochthonous sources when discharge and flushing time are elevated at which times SUVA254 and HIX increased relative to base flow. During periods of reduced discharge and long flushing times in the estuary, extensive autochthonous production modifies the quality of the DOM pool in the NRE. This was evidenced by falling C:N values, and higher BIX and SR values. Lastly, a combination of increased wind speed and shifts in wind direction resulted in benthic resuspension events of degraded, planktonic OM. Thus, the mean DOM characteristics in this shallow micro-tidal estuary can be rapidly altered during episodic mixing events on timescales of a few weeks. DA - 2014/12/5/ PY - 2014/12/5/ DO - 10.1016/j.ecss.2014.10.013 VL - 151 SP - 210-220 SN - 1096-0015 KW - estuary KW - CDOM KW - DOM KW - discharge KW - flushing time KW - wind-driven mixing ER - TY - JOUR TI - RADAR IN ATMOSPHERIC SCIENCES AND RELATED RESEARCH Current Systems, Emerging Technology, and Future Needs AU - Bluestein, Howard B. AU - Rauber, Robert M. AU - Burgess, Donald W. AU - Albrecht, Bruce AU - Ellis, Scott M. AU - Richardson, Yvette P. AU - Jorgensen, David P. AU - Frasier, Stephen J. AU - Chilson, Phillip AU - Palmer, Robert D. AU - Yuter, Sandra E. AU - Lee, Wen-Chau AU - Dowell, David C. AU - Smith, Paul L. AU - Markowski, Paul M. AU - Friedrich, Katja AU - Weckwerth, Tammy M. T2 - BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY AB - To assist the National Science Foundation in meeting the needs of the community of scientists by providing them with the instrumentation and platforms necessary to conduct their research successfully, a meeting was held in late November 2012 with the purpose of defining the problems of the next generation that will require radar technologies and determining the suite of radars best suited to help solve these problems. This paper summarizes the outcome of the meeting: (i) Radars currently in use in the atmospheric sciences and in related research are reviewed. (ii) New and emerging radar technologies are described. (iii) Future needs and opportunities for radar support of high-priority research are discussed. The current radar technologies considered critical to answering the key and emerging scientific questions are examined. The emerging radar technologies that will be most helpful in answering the key scientific questions are identified. Finally, gaps in existing radar observing technologies are listed. DA - 2014/12// PY - 2014/12// DO - 10.1175/bams-d-13-00079.1 VL - 95 IS - 12 SP - 1850-1861 SN - 1520-0477 ER - TY - JOUR TI - On the periodicity of atmospheric von Karman vortex streets AU - Nunalee, Christopher G. AU - Basu, Sukanta T2 - ENVIRONMENTAL FLUID MECHANICS DA - 2014/12// PY - 2014/12// DO - 10.1007/s10652-014-9340-9 VL - 14 IS - 6 SP - 1335-1355 SN - 1573-1510 KW - Island wakes KW - Marine boundary layer KW - Stably stratified flows KW - Strouhal number KW - Von Karman vortex street ER - TY - JOUR TI - Numerical Simulations of Bow Echo Formation Following a Squall Line-Supercell Merger AU - French, Adam J. AU - Parker, Matthew D. T2 - MONTHLY WEATHER REVIEW AB - Abstract Output from idealized numerical simulations is used to investigate the storm-scale processes responsible for squall-line evolution following a merger with an isolated supercell. A simulation including a squall line–supercell merger is compared to one using the same initial squall line and background environment without the merger. These simulations reveal that while bow echo formation is favored by the strongly sheared background environment, the merger produces a more compact bowing structure owing to a locally enhanced rear-inflow jet. The merger also represents a favored location for severe weather production relative to other portions of the squall line, with surface winds, vertical vorticity, and rainfall all being maximized in the vicinity of the merger. An analysis of storm-scale processes reveals that the premerger squall line weakens as it encounters outflow from the preline supercell, and the supercell becomes the leading edge of the merged system. Subsequent localized strengthening of the cold pool and rear-inflow jet produce a compact, intense bow echo local to the merger, with a descending rear-inflow jet creating a broad swath of damaging surface winds. These features, common to severe bow echoes, are shown to be a direct result of the merger in the present simulations, and are diminished or absent in the no-merger simulation. Sensitivity tests reveal that mergers in a weaker vertical wind shear environment do not produce an enhanced bow echo structure, and only produce a localized region of marginally enhanced surface winds. Additional tests demonstrate that the details of postmerger evolution vary with merger location along the line. DA - 2014/12// PY - 2014/12// DO - 10.1175/mwr-d-13-00356.1 VL - 142 IS - 12 SP - 4791-4822 SN - 1520-0493 ER - TY - JOUR TI - Eulerian dispersion modeling with WRF-LES of plume impingement in neutrally and stably stratified turbulent boundary layers AU - Nunalee, C. G. AU - Kosovic, B. AU - Bieringer, P. E. T2 - Atmospheric Environment DA - 2014/// PY - 2014/// VL - 99 SP - 571-581 ER - TY - JOUR TI - Detrital Zircon Geochronology Across the Chopawamsic Fault, Western Piedmont of North-Central Virginia: Implications for the Main Iapetan Suture in the Southern Appalachian Orogen AU - Hughes, K. Stephen AU - Hibbard, James P. AU - Pollock, Jeffrey C. AU - Lewis, David J. AU - Miller, Brent V. T2 - GEOSCIENCE CANADA AB - The Chopawamsic fault potentially represents the main Iapetan suture, previously unidentified in the southern extent of the Appalachian orogen. The fault trends through the north-central portion of the western Piedmont of Virginia and separates the composite metaclastic Potomac terrane, commonly interpreted to be of Laurentian affinity, from the Chopawamsic terrane, the remains of a Middle Ordovician volcanic arc of uncertain crustal affinity. To gain insight on the first-order orogenic significance of the Chopawamsic fault, we report the results of LA–ICP–MS U–Pb analyses of 1,289 detrital zircons from 13 metasedimentary rock samples collected from both sides of the fault. The near exclusivity of Middle Ordovician zircon grains (ca. 470 – 460 Ma) in four sampled metasedimentary rocks of the Chopawamsic Formation likely represents the detrital recycling of syndepositional Chopawamsic volcanic rocks. A subset of Cambrian and older grains hint at one or more additional, older sources. Samples from the Potomac terrane include mostly Mesoproterozoic zircon grains and these results are consistent with previous interpretations that the metaclastic rocks are Laurentian-derived. The youngest zircons (ca. 550 – 500 Ma) and the age of cross-cutting plutons indicate that at least some parts of the Potomac terrane are Late Cambrian – Early Ordovician. The results imply temporally discrete and geographically isolated sedimentary systems during deposition of sedimentary rocks in the Chopawamsic and Potomac terranes. Metasedimentary rocks near Storck, Virginia, previously identified as a successor basin, contain detrital zircon populations that indicate they are actually peri-Gondwanan derived metasedimentary rocks unrelated to a successor basin system; their geographic position between the Laurentian-derived Potomac terrane and the Chopawamsic terrane suggests a peri-Gondwanan affinity for the Chopawamsic arc and geographic separation of the Chopawamsic and Potomac terranes in the Middle Ordovician. Consequently, we tentatively support the hypothesis that the Chopawamsic fault system represents the main Iapetan suture in the southern Appalachian orogen. Most detrital zircons from samples of the Arvonia successor basin crystallized in the Ordovician—Silurian or Mesoproterozoic. These data suggest that the Arvonia basin was deposited in the latest Ordovician to Early Silurian only after the Late Ordovician accretion of the Chopawamsic arc to Laurentia. SOMMAIRELa faille de Chopawamsic représente peut-être la principale suture japétienne, non-reconnue dans prolongement sud de l’orogène des Appalaches. La faille traverse la portion nord du centre du piedmont ouest de Virginie et sépare le terrane métaclastique de Potomac, d’affinité laurentienne pensait-on, du terrane de Chopawamsic, vestige d’un arc volcanique de l’Ordovicien moyen d’affinité crustale incertain. Afin de mettre en lumière la signification orogénique première de la faille de Chopawamsic, nous présentons les résultats d’analyses U-Pb par ICP–MS par AL sur 1 289 zircons détritiques provenant de 13 échantillons de roches métasédimentaires prélevés de chaque côté de la faille. L’existence quasi-exclusive de grains de zircon de l’Ordovicien moyen (env. 470 – 460 Ma) dans quatre roches métasédimentaires de la Formation de Chopawamsic représente vraisemblablement le recyclage détritique des roches volcaniques synsédimentaires de Chopawamsic. Un sous-ensemble de grains cambriens et plus anciens, évoque l’existence d’une ou plusieurs sources plus anciennes additionnelles. Les échantillons du terrane de Potomac renferment principalement des grains de zircon du Mésoprotérozoïque, ce qui correspond avec les interprétations antérieures voulant que les roches métaclastiques soient d’origine laurentienne. Les zircons les plus jeunes (env. 550 – 500 Ma) ainsi que l’âge des plutons qui recoupe l’encaissant indiquent qu’au moins certaines parties du terrane de Potomac sont de la fin du Cambrien ou du début de l’Ordovicien. Les résultats impliquent l’existence de systèmes sédimentaires distincts au cours du temps, et isolés géographiquement durant le dépôt des roches sédimentaires dans les terranes de Chopawamsic et de Potomac. Les roches métasédimentaires près de Storck en Virginie, jadis interprétées comme bassin successeur, renferment des populations de zircons détritiques qui indiquent qu’ils proviennent en fait de roches métasédimentaires péri-gondwaniennes sans rapport avec un système de bassin successeur; leur localisation géographique entre le terrane de Potomac issu des Laurentides et le terrane de Chopawamsic porte à penser que l’arc de Chopawamsic est d’affinité péri-gondwanienne, et que les terranes de Chopawamsic et de Potomac à l’Ordovicien moyen étaient séparés géographiquement. En conséquence il nous semble justifié de proposer que le système de faille de Chopawamsic représente la principale suture japétienne dans le sud de l’orogène des Appalaches. La plupart des zircons détritiques des échantillons du bassin successeur d’Arvonia ont cristallisés entre l’Ordovicien et le Silurien ou au Mésoprotérozoïque. Ces données suggèrent que le bassin d’Arvonia s’est rempli de la fin entre l’Ordovicien et le début du Silurien, seulement après l’accrétion de l’arc de Chopawamsic à la Laurentie, à la fin de l’Ordovicien. DA - 2014/// PY - 2014/// DO - 10.12789/geocanj.2014.41.052 VL - 41 SP - 503-522 SN - 0315-0941 ER - TY - JOUR TI - Comparison of NCEP Multisensor Precipitation Estimates with Independent Gauge Data over the Eastern United States AU - Wootten, Adrienne AU - Boyles, Ryan P. T2 - JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY AB - Abstract Gauge-calibrated radar estimates of daily precipitation are compared with daily observed values of precipitation from National Weather Service (NWS) Cooperative Observer Network (COOP) stations to evaluate the multisensor precipitation estimate (MPE) product that is gridded by the National Centers for Environmental Prediction (NCEP) for the eastern United States (defined as locations east of the Mississippi River). This study focuses on a broad evaluation of MPE across the study domain by season and intensity. In addition, the aspect of precipitation type is considered through case studies of winter and summer precipitation events across the domain. Results of this study indicate a north–south gradient in the error of MPE and a seasonal pattern with the highest error in summer and autumn and the lowest error in winter. Two case studies of precipitation are also considered in this study. These case studies include instances of intense precipitation and frozen precipitation. These results suggest that MPE is less able to estimate convective-scale precipitation as compared with precipitation variations at larger spatial scales. In addition, the results suggest that MPE is subject to errors related both to the measurement gauges and to the radar estimates used. Two case studies are also included to discuss the differences with regard to precipitation type. The results from these case studies suggest that MPE may have higher error associated with estimating the liquid equivalent of frozen precipitation when compared with NWS COOP network data. The results also suggest the need for more analysis of MPE error for frozen precipitation in diverse topographic regimes. DA - 2014/12// PY - 2014/12// DO - 10.1175/jamc-d-14-0034.1 VL - 53 IS - 12 SP - 2848-2862 SN - 1558-8432 ER - TY - JOUR TI - A Pelomedusoid Turtle from the Paleocene-Eocene of Colombia Exhibiting Preservation of Blood Vessels and Osteocytes AU - Cadena, Edwin A. AU - Schweitzer, Mary H. T2 - JOURNAL OF HERPETOLOGY AB - We describe a Paleocene–Eocene pelomedusoid turtle from tropical South America in a new fossiliferous locality, from Los Cuervos Formation, at the Calenturitas Coal Mine, Colombia. Although no further systematic precision beyond Pelomedusoides incertae sedis can be supported, the presence of an ischial scar positioned far anteriorly to the anal notch, and a strongly decorated ventral surface of the plastron, indicate that this specimen is potentially related to the bothremydid clade formed by Puentemys–Foxemys. We also demonstrate the potential organic preservation of osteocytes and blood vessels for this specimen, indicating that preservation of soft tissue such as vessels and bone cells in the fossil record is independent of bone type, fossil site, or locality; occurring in different lineages of vertebrates; and that it is even possible to occur in tropical depositional environments during a period of maximum global warming such as the Paleocene–Eocene.Aqui describimos la primera ocurencia de tortugas pelomedusoid del Paleoceno–Eoceno en la parte tropical de Suramérica, en una nueva localidad fósilifera, de la Formación Los Cuervos, en la mina de carbón Calenturitas, Colombia. Aunque, no mayor precisión sistemática puede ser soportada más que Pelomedusoides incertae sedis, la presencia de una cicatriz isquial posicionada muy anteriormente a la escotadura anal y una fuertemente decorada superficie ventral del plastron, indican que el especimen esta relacionado con el clado bothremydido formado por Puentemys–Foxemys. También demostramos la posible preservación orgánica de osteocitos y vasos sanguineos para este especimen; indicando que la preservación de tejidos blandos como vasos y celulas oseas en el registro fósil es independiente del tipo de hueso, sitio fósil o localidad, ocurriendo en diferentes linajes de vertebrados, y que es possible que ocurra en ambientes deposicionales tropicales, durante periodos de maximo calentamiento global como el Paleoceno–Eoceno. DA - 2014/12// PY - 2014/12// DO - 10.1670/13-046 VL - 48 IS - 4 SP - 461-465 SN - 1937-2418 ER - TY - JOUR TI - Will the role of intercontinental transport change in a changing climate? AU - Glotfelty, T. AU - Zhang, Y. AU - Karamchandani, P. AU - Streets, D. G. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 17 SP - 9379-9402 ER - TY - JOUR TI - Source apportionment of VOCs in a suburb of Nanjing, China, in autumn and winter AU - Xia, L. AU - Cai, C. J. AU - Zhu, B. AU - An, J. L. AU - Li, Y. Y. AU - Li, Y. T2 - Journal of Atmospheric Chemistry DA - 2014/// PY - 2014/// VL - 71 IS - 3 SP - 175-193 ER - TY - JOUR TI - Seasonal variability of Kuroshio intrusion northeast of Taiwan Island as revealed by self-organizing map AU - Yuqi, Yin AU - Xiaopei, Lin AU - Yizhen, Li AU - Xiangming, Zeng T2 - CHINESE JOURNAL OF OCEANOLOGY AND LIMNOLOGY DA - 2014/11// PY - 2014/11// DO - 10.1007/s00343-015-4017-x VL - 32 IS - 6 SP - 1435-1442 SN - 1993-5005 KW - Kuroshio intrusion KW - self-organizing map KW - mesoscale eddies ER - TY - JOUR TI - Observed influence of riming, temperature, and turbulence on the fallspeed of solid precipitation AU - Garrett, Timothy J. AU - Yuter, Sandra E. T2 - GEOPHYSICAL RESEARCH LETTERS AB - Forecasts of the amount and geographic distribution of snow are highly sensitive to a model's parameterization of hydrometeor fallspeed. Riming is generally thought to lead to particles with a higher mass and terminal velocity. Yet models commonly assume that heavily rimed particles such as graupel have a fixed density and that their settling speed is unaffected by turbulence in storms. Here we show automated measurements of photographed hydrometeor shape and fallspeed using a new instrument placed in Utah's Wasatch Mountain Range. The data show that graupel in low-turbulence conditions has a size-dependent fallspeed distribution with a mode near 1 m s−1, a result that is generally consistent with prior observations. However, the distributions are broadened by turbulence and there is a correspondence between particle density and air temperature. In high turbulence and at low temperatures, any sensitivity of fallspeed to particle size disappears. DA - 2014/9/28/ PY - 2014/9/28/ DO - 10.1002/2014gl061016 VL - 41 IS - 18 SP - 6515-6522 SN - 1944-8007 ER - TY - JOUR TI - Incorporation of advanced aerosol activation treatments into CESM/CAM5: model evaluation and impacts on aerosol indirect effects AU - Gantt, B. AU - He, J. AU - Zhang, X. AU - Zhang, Y. AU - Nenes, A. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 14 SP - 7485-7497 ER - TY - JOUR TI - Improvement and further development in CESM/CAM5: gas-phase chemistry and inorganic aerosol treatments AU - He, J. AU - Zhang, Y. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 17 SP - 9171-9200 ER - TY - JOUR TI - Dynamical downscaling of climate change impacts on wind energy resources in the contiguous United States by using a limited-area model with scale-selective data assimilation AU - Liu, B. AU - Costa, K. B. AU - Xie, L. AU - Semazzi, F. H. M. T2 - Advances in Meteorology AB - By using a limited-area model (LAM) in combination with the scale-selective data assimilation (SSDA) approach, wind energy resources in the contiguous United States (CONUS) were downscaled from IPCC CCSM3 global model projections for both current and future climate conditions. An assessment of climate change impacts on wind energy resources in the CONUS region was then conducted. Based on the downscaling results, when projecting into future climate under IPCC’s A1B scenario, the average annual wind speed experiences an overall shift across the CONUS region. From the current climate to the 2040s, the average annual wind speed is expected to increase from 0.1 to 0.2 m s −1 over the Great Plains, Northern Great Lakes Region, and Southwestern United States located southwest of the Rocky Mountains. When projecting into the 2090s from current climate, there is an overall increase in the Great Plains Region and Southwestern United States located southwest of the Rockies with a mean wind speed increase between 0 and 0.1 m s −1 , while, the Northern Great Lakes Region experiences an even greater increase from current climate to 2090s than over the first few decades with an increase of mean wind speed from 0.1 to 0.4 m s −1 . DA - 2014/// PY - 2014/// DO - 10.1155/2014/897246 ER - TY - JOUR TI - Droplet activation of wet particles: development of the Wet CCN approach AU - Nakao, S. AU - Suda, S. R. AU - Camp, M. AU - Petters, M. D. AU - Kreidenweis, S. M. T2 - Atmospheric Measurement Techniques DA - 2014/// PY - 2014/// VL - 7 IS - 7 SP - 2227-2241 ER - TY - JOUR TI - Different Modes of Variability over the Tasman Sea: Implications for Regional Climate AU - Liess, Stefan AU - Kumar, Arjun AU - Snyder, Peter K. AU - Kawale, Jaya AU - Steinhaeuser, Karsten AU - Semazzi, Frederick H. M. AU - Ganguly, Auroop R. AU - Samatova, Nagiza F. AU - Kumar, Vipin T2 - JOURNAL OF CLIMATE AB - Abstract A new approach is used to detect atmospheric teleconnections without being bound by orthogonality (such as empirical orthogonal functions). This method employs negative correlations in a global dataset to detect potential teleconnections. One teleconnection occurs between the Tasman Sea and the Southern Ocean. It is related to El Niño–Southern Oscillation (ENSO), the Indian Ocean dipole (IOD), and the southern annular mode (SAM). This teleconnection is significantly correlated with SAM during austral summer, fall, and winter, with IOD during spring, and with ENSO in summer. It can thus be described as a hybrid between these modes. Given previously found relationships between IOD and ENSO, and IOD’s proximity to the teleconnection centers, correlations to IOD are generally stronger than to ENSO. Increasing pressure over the Tasman Sea leads to higher (lower) surface temperature over eastern Australia (the southwestern Pacific) in all seasons and is related to reduced surface temperature over Wilkes Land and Adélie Land in Antarctica during fall and winter. Precipitation responses are generally negative over New Zealand. For one standard deviation of the teleconnection index, precipitation anomalies are positive over Australia in fall, negative over southern Australia in winter and spring, and negative over eastern Australia in summer. When doubling the threshold, the size of the anomalous high-pressure center increases and annual precipitation anomalies are negative over southeastern Australia and northern New Zealand. Eliassen–Palm fluxes quantify the seasonal dependence of SAM, ENSO, and IOD influences. Analysis of the dynamical interactions between these teleconnection patterns can improve prediction of seasonal temperature and precipitation patterns in Australia and New Zealand. DA - 2014/11/15/ PY - 2014/11/15/ DO - 10.1175/jcli-d-13-00713.1 VL - 27 IS - 22 SP - 8466-8486 SN - 1520-0442 KW - Australia KW - Southern Ocean KW - Annular mode KW - ENSO KW - Teleconnections KW - Drought ER - TY - JOUR TI - Soundscape variation from a larval perspective: the case for habitat-associated sound as a settlement cue for weakly swimming estuarine larvae AU - Lillis, Ashlee AU - Eggleston, David B. AU - Bohnenstiehl, DelWayne R. T2 - MARINE ECOLOGY PROGRESS SERIES AB - MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 509:57-70 (2014) - DOI: https://doi.org/10.3354/meps10917 Soundscape variation from a larval perspective: the case for habitat-associated sound as a settlement cue for weakly swimming estuarine larvae Ashlee Lillis*, David B. Eggleston, DelWayne R. Bohnenstiehl Department of Marine, Earth & Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695-8208, USA *Corresponding author: aslillis@ncsu.edu ABSTRACT: Settlement is a critical phase in the life history of most benthic marine organisms and has important implications for their survival and reproductive success, and ultimately for population and community dynamics. Larval encounter with settlement habitats is likely facilitated through the use of habitat-specific physical and chemical cues, but the scales over which particular habitat-related environmental cues may operate are rarely measured. In Pamlico Sound, North Carolina, USA we used passively drifting acoustic recorders to measure the variation in habitat-related underwater sound, a potential broad-scale settlement cue, at spatiotemporal scales relevant to dispersing bivalve larvae in the estuary. Sound levels increased by up to 30 dB during passage over oyster reefs compared to off-reef soft bottom areas, and sound level fluctuations in the 2000 to 23000 Hz frequency range closely corresponded to the presence of oyster reef patches below drifters, indicating that sound characteristics could reliably provide a signal of benthic habitat type to planktonic larvae. Using these soundscape measurements and the known descent capabilities of oyster larvae, we demonstrate with a conceptual model that response to habitat-related sound cues is a feasible mechanism for enhanced larval encounter with settlement substrate. KEY WORDS: Soundscape ecology · Larval habitat cues · Acoustic patterns · Hydrophone drifters · Oyster reefs · Passive acoustics Full text in pdf format PreviousNextCite this article as: Lillis A, Eggleston DB, Bohnenstiehl DR (2014) Soundscape variation from a larval perspective: the case for habitat-associated sound as a settlement cue for weakly swimming estuarine larvae. Mar Ecol Prog Ser 509:57-70. https://doi.org/10.3354/meps10917 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 509. Online publication date: August 27, 2014 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2014 Inter-Research. DA - 2014/// PY - 2014/// DO - 10.3354/meps10917 VL - 509 SP - 57-70 SN - 1616-1599 KW - Soundscape ecology KW - Larval habitat cues KW - Acoustic patterns KW - Hydrophone drifters KW - Oyster reefs KW - Passive acoustics ER - TY - JOUR TI - Radar Climatology of Tornadic and Nontornadic Vortices in High-Shear, Low-CAPE Environments in the Mid-Atlantic and Southeastern United States AU - Davis, Jason M. AU - Parker, Matthew D. T2 - WEATHER AND FORECASTING AB - Abstract Tornadoes occurring in environments characterized by strong vertical wind shear [0–6-km bulk wind difference ≥35 knots (kt; 1 kt = 0.51 m s−1) (18 m s−1)] but low CAPE (&lt;500 J kg−1) are an important challenge for forecasters, especially in the mid-Atlantic and southeastern United States. In this study, 95 tornadic and 135 nontornadic vortices were tracked in high-shear, low-CAPE (HSLC) environments. Values of azimuthal shear were recorded along the vortex tracks, and operationally relevant radar reflectivity signatures were also manually identified in association with these vortices. Statistically significant differences in azimuthal shear were found between tornadic and nontornadic vortices within 60 km of the radar, particularly near the surface. Although there were significant differences between tornadic and nontornadic vortices from nonsupercells (primarily quasi-linear convective systems), this was not the case for supercellular vortices. Beyond 60 km from the radar, no statistically significant differences were found. Numerous reflectivity signatures were also studied, including hook echoes and weak-echo regions associated with supercell vortices, as well as rear-inflow notches, bowing segments, and forward-inflow notches associated with nonsupercell vortices. These signatures were found to have a high probability of detection close to the radar, but also a high false alarm rate, and were observed much less often &gt;100 km from the radar. Overall, while azimuthal shear and radar reflectivity signatures show the potential for high probability of detection in close proximity to operational radars, high false alarm rates, and short lead times appear to be an unavoidable trade-off in HSLC environments. DA - 2014/8// PY - 2014/8// DO - 10.1175/waf-d-13-00127.1 VL - 29 IS - 4 SP - 828-853 SN - 1520-0434 ER - TY - JOUR TI - Imported and Storm-Generated Near-Ground Vertical Vorticity in a Simulated Supercell AU - Dahl, Johannes M. L. AU - Parker, Matthew D. AU - Wicker, Louis J. T2 - JOURNAL OF THE ATMOSPHERIC SCIENCES AB - Abstract The authors use a high-resolution supercell simulation to investigate the source of near-ground vertical vorticity by decomposing the vorticity vector into barotropic and nonbarotropic parts. This way, the roles of ambient and storm-generated vorticity can be isolated. A new Lagrangian technique is employed in which material fluid volume elements are tracked to analyze the rearrangement of ambient vortex-line segments. This contribution is interpreted as barotropic vorticity. The storm-generated vorticity is treated as the residual between the known total vorticity and the barotropic vorticity. In the simulation the development of near-ground vertical vorticity is an outflow phenomenon. There are distinct “rivers” of cyclonic shear vorticity originating from the base of downdrafts that feed into the developing near-ground vortex. The origin of these rivers of vertical vorticity is primarily horizontal baroclinic production, which is maximized in the lowest few hundred meters AGL. Subsequently, this horizontal vorticity is tilted upward while the parcels are still descending. The barotropic vorticity remains mostly streamwise along the analyzed trajectories and does not acquire a large vertical component as the parcels reach the ground. Thus, the ambient vorticity that is imported into the storm contributes only a small fraction of the total near-ground vertical vorticity. DA - 2014/8// PY - 2014/8// DO - 10.1175/jas-d-13-0123.1 VL - 71 IS - 8 SP - 3027-3051 SN - 1520-0469 ER - TY - JOUR TI - Combined phylogenetic analysis of a new North American fossil species confirms widespread Eocene distribution for stem rollers (vol 157, pg 586, 2009) AU - Clarke, J. A. AU - Ksepka, D. T. AU - Smith, N. A. AU - Norell, M. A. T2 - Zoological Journal of the Linnean Society DA - 2014/// PY - 2014/// VL - 172 IS - 1 SP - 226-229 ER - TY - JOUR TI - Climatology and Ingredients of Significant Severe Convection in High-Shear, Low-CAPE Environments AU - Sherburn, Keith D. AU - Parker, Matthew D. T2 - WEATHER AND FORECASTING AB - Abstract High-shear, low-CAPE (HSLC) environments, here characterized by surface-based CAPE ≤ 500 J kg−1, most unstable parcel CAPE ≤ 1000 J kg−1, and 0–6-km shear vector magnitude ≥ 18 m s−1, occur at all times of day, across all seasons, and throughout the entire United States. HSLC environments represent a unique challenge for forecasters, as they occur frequently but produce severe weather a relatively low percentage of the time. Recent studies have primarily focused on improving nowcasting and warnings for events through the identification of radar signatures commonly associated with HSLC tornadoes. Few studies have investigated the forecasting of HSLC severe weather, despite the acknowledged poor performance of traditional tools and techniques. A general climatology of HSLC significant severe weather is presented, focusing on regional, diurnal, and annual trends. Through this climatology, it becomes apparent that multiple types of HSLC environments are possible, including surface-based cases with low lifted condensation levels and high-based convection cases. A statistical analysis of HSLC events and nulls from the southeastern and mid-Atlantic states is utilized to assess the performance of conventional composite parameters in HSLC environments. Additionally, a new composite parameter is introduced that utilizes the product of the statistically most skillful parameters in HSLC environments: the 0–3-km lapse rate, the 700–500-hPa lapse rate, and multiple wind and shear metrics. The strengths and weaknesses of these ingredients-based techniques are then reviewed, with an eye toward improving future HSLC severe weather forecasts. DA - 2014/8// PY - 2014/8// DO - 10.1175/waf-d-13-00041.1 VL - 29 IS - 4 SP - 854-877 SN - 1520-0434 ER - TY - JOUR TI - Characterizing reduced sulfur compounds emissions from a swine concentrated animal feeding operation AU - Rumsey, Ian C. AU - Aneja, Viney P. AU - Lonneman, William A. T2 - ATMOSPHERIC ENVIRONMENT AB - Reduced sulfur compounds (RSCs) emissions from concentrated animal feeding operations (CAFOs) have become a potential environmental and human health concern, as a result of changes in livestock production methods. RSC emissions were determined from a swine CAFO in North Carolina. RSC measurements were made over a period of ≈1 week from both the barn and lagoon during each of the four seasonal periods from June 2007 to April 2008. During sampling, meteorological and other environmental parameters were measured continuously. Seasonal hydrogen sulfide (H2S) barn concentrations ranged from 72 to 631 ppb. Seasonal dimethyl sulfide (DMS; CH3SCH3) and dimethyl disulfide (DMDS; CH3S2CH3) concentrations were 2–3 orders of magnitude lower, ranging from 0.18 to 0.89 ppb and 0.47 to 1.02 ppb, respectively. The overall average barn emission rate was 3.3 g day−1 AU−1 (AU (animal unit) = 500 kg of live animal weight) for H2S, which was approximately two orders of magnitude higher than the DMS and DMDS overall average emissions rates, determined as 0.017 g day−1 AU−1 and 0.036 g day−1 AU−1, respectively. The overall average lagoon flux was 1.33 μg m−2 min−1 for H2S, which was approximately an order of magnitude higher than the overall average DMS (0.12 μg m−2 min−1) and DMDS (0.09 μg m−2 min−1) lagoon fluxes. The overall average lagoon emission for H2S (0.038 g day−1 AU−1) was also approximately an order of magnitude higher than the overall average DMS (0.0034 g day−1 AU−1) and DMDS (0.0028 g day−1 AU−1) emissions. H2S, DMS and DMDS have offensive odors and low odor thresholds. Over all four sampling seasons, 77% of 15 min averaged H2S barn concentrations were an order of magnitude above the average odor threshold. During these sampling periods, however, DMS and DMDS concentrations did not exceed their odor thresholds. The overall average barn and lagoon emissions from this study were used to help estimate barn, lagoon and total (barn + lagoon) RSC emissions from swine CAFOs in North Carolina. Total (barn + lagoon) H2S emissions from swine CAFOs in North Carolina were estimated to be 1.22*106 kg yr−1. The barns had significantly higher H2S emissions than the lagoons, contributing ≈98% of total North Carolina H2S swine CAFO emissions. Total (barn + lagoon) emissions for DMS and DMDS were 1–2 orders of magnitude lower, with barns contributing ≈86% and ≈93% of total emissions, respectively. H2S swine CAFO emissions were estimated to contribute ≈18% of North Carolina H2S emissions. DA - 2014/9// PY - 2014/9// DO - 10.1016/j.atmosenv.2014.05.041 VL - 94 SP - 458-466 SN - 1873-2844 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84901479235&partnerID=MN8TOARS KW - Reduced sulfur compounds KW - Hydrogen sulfide KW - CAFO emissions KW - Swine ER - TY - JOUR TI - A gigantic, exceptionally complete Titanosaurian sauropod dinosaur from Southern Patagonia, Argentina AU - Lacovara, K. J. AU - Lamanna, M. C. AU - Ibiricu, L. M. AU - Poole, J. C. AU - Schroeter, E. R. AU - Ullmann, P. V. AU - Voegele, K. K. AU - Boles, Z. M. AU - Carter, A. M. AU - Fowler, E. K. AU - Egerton, V. M. AU - Moyer, A. E. AU - Coughenour, C. L. AU - Schein, J. P. AU - Harris, J. D. AU - Martinez, R. D. T2 - Scientific Reports DA - 2014/// PY - 2014/// VL - 4 ER - TY - JOUR TI - The Role of the Dominant Modes of Precipitation Variability over Eastern Africa in Modulating the Hydrology of Lake Victoria AU - Smith, Kara A. AU - Semazzi, Fredrick H. M. T2 - ADVANCES IN METEOROLOGY AB - Previous water budget studies over Lake Victoria basin have shown that there is near balance between rainfall and evaporation and that the variability of Lake Victoria levels is determined virtually entirely by changes in rainfall since evaporation is nearly constant. The variability of rainfall over East Africa is dominated by El Niño-Southern Oscillation (ENSO); however, the second and third most dominant rainfall climate modes also account for significant variability across the region. The relationship between ENSO and other significant modes of precipitation variability with Lake Victoria levels is nonlinear. This relationship should be studied to determine which modes need to be accurately modeled in order to accurately model Lake Victoria levels, which are important to the hydroelectric industry in East Africa. The objective of this analysis is to estimate the relative contributions of the dominant modes of annual precipitation variability to the modulation of Lake Victoria levels for the present day (1950–2012). The first mode of annual rainfall variability accounts for most of the variability in Lake Victoria levels, while the effects of the second and third modes are negligible even though these modes are also significant over the region. DA - 2014/// PY - 2014/// DO - 10.1155/2014/516762 VL - 2014 SP - SN - 1687-9317 ER - TY - JOUR TI - The Impact of Radiation on the GABLS3 Large-Eddy Simulation through the Night and during the Morning Transition AU - Edwards, J. M. AU - Basu, S. AU - Bosveld, F. C. AU - Holtslag, A. A. M. T2 - BOUNDARY-LAYER METEOROLOGY DA - 2014/8// PY - 2014/8// DO - 10.1007/s10546-013-9895-x VL - 152 IS - 2 SP - 189-211 SN - 1573-1472 KW - GABLS3 KW - Large-eddy simulation KW - Morning transition KW - Radiation KW - Stable boundary layer ER - TY - JOUR TI - Surface Microphysical Observations within East Coast Winter Storms on Long Island, New York AU - Colle, Brian A. AU - Stark, David AU - Yuter, Sandra E. T2 - MONTHLY WEATHER REVIEW AB - Abstract Surface observations of ice habit and degree of riming were measured for 12 cyclone events over 3 winter seasons at Stony Brook, New York, on the northeast coast of the United States. A total of 205.6 cm of snow accumulated during these storms, with an average degree of riming of 1.25 (out of 5) and snow-to-liquid ratio ranging from 3:1 to 17:1. There were consistent spatial patterns of habit and riming intensity relative to the cyclone structure. Cold-type habits (side planes and bullets) commonly occurred within the outer comma head to the north and northeast of the cyclone center. In the middle of the comma head, moderately rimed dendrites, plates, and needles were observed. Close to the cyclone center, heavy riming was observed with needles and graupel. The western quadrant of the comma head had primarily plates and dendrites with little to no riming. Periods of light riming and high snow–liquid ratios (≥13:1) are dominated by cold-type habits, dendrites, and plates and have similar vertical motion and synoptic characteristics inferred from 13-km Rapid Update Cycle analyses. Maximum vertical motion occurred in a region of favored ice growth and less supercooled water (from −15° to −25°C). During heavy riming periods, needles and graupel are dominant and the vertical motion maximum occurs at temperatures from 0° to −5°C. Vertically pointing Micro Rain Radar indicates stronger vertical motions and turbulence for heavy riming as opposed to light rimming periods. Periods with low snow-to-liquid ratio (≤7:1) were observed to occur either as heavy rimed particles or as light riming of compact habits such as sideplanes, bullets, and needles. DA - 2014/9// PY - 2014/9// DO - 10.1175/mwr-d-14-00035.1 VL - 142 IS - 9 SP - 3126-3146 SN - 1520-0493 ER - TY - JOUR TI - Salt Marsh Sediment Biogeochemical Response to the BP Deepwater Horizon Blowout AU - Mills, Calista G. AU - McNeal, Karen S. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - The impact of the blowout on salt marshes was investigated by observing the biogeochemistry in salt marsh sediments along the Gulf Coast. High sulfide levels due to hydrocarbon loading, increased microbial activity, and microbial community shifts can lead to plant browning and mortality. Sediment biogeochemical processes that degrade enriched carbon pools through sulfate reduction are primarily responsible for the biodegradation of spilled hydrocarbons. An assessment of the impact of contamination on salt marshes at Skiff Island, LA, and Cat Island, Marsh Point, and Saltpan Island, MS, was achieved through sediment electrode profiling, microbial community profiling, and quantification of hydrocarbon contamination, which captured the spatial sedimentary biogeochemical response that affects salt marsh productivity. At western locations (Skiff and Cat Islands), total petroleum hydrocarbons (TPHs) ranged from 2183 to 2996 mg kg, which was more than double the TPH concentration observed at eastern locales. At eastern study locations (e.g., Marsh Point), sedimentary pore-water HS concentrations were higher (maximum value = 231 mg L) and detected further up in the sediment column than at western locales (e.g., Skiff Island). Similarly, anaerobic and aerobic microbial activity, as measured by C substrate utilization profiles and well-color development, was as high or higher at eastern locations as compared with western locations. These results indicate that other factors besides location or degree of contamination, perhaps sedimentary dynamics and physical processes specific to each marsh, should be considered when determining salt marsh response to hydrocarbon contamination. DA - 2014/// PY - 2014/// DO - 10.2134/jeq2013.11.0441 VL - 43 IS - 5 SP - 1813-1819 SN - 1537-2537 ER - TY - JOUR TI - Reconstructing the Prevailing Meteorological and Optical Environment during the Time of the Titanic Disaster AU - Basu, Sukanta AU - Nunalee, Christopher G. AU - He, Ping AU - Fiorino, Steven T. AU - Vorontsov, Mikhail A. T2 - LASER COMMUNICATION AND PROPAGATION THROUGH THE ATMOSPHERE AND OCEANS III AB - In this paper, we reconstruct the meteorological and optical environment during the time of Titanic’s disaster utilizing a state-of-the-art meteorological model, a ray-tracing code, and a unique public-domain dataset called the Twentieth Century Global Reanalysis. With high fidelity, our simulation captured the occurrence of an unusually high Arctic pressure system over the disaster site with calm wind. It also reproduced the movement of a polar cold front through the region bringing a rapid drop in air temperature. The simulated results also suggest that unusual meteorological conditions persisted several hours prior to the Titanic disaster which contributed to super-refraction and intermittent optical turbulence. However, according to the simulations, such anomalous conditions were not present at the time of the collision of Titanic with an iceberg. DA - 2014/// PY - 2014/// DO - 10.1117/12.2063195 VL - 9224 SP - SN - 1996-756X KW - 1VIesoscale Mcleling KW - Optical Turbulence KW - Ray Tracing KW - Refraction ER - TY - JOUR TI - Moisture Variability and Multiscale Interactions during Spring in West Africa AU - Mera, Roberto AU - Laing, Arlene G. AU - Semazzi, Frederick T2 - Monthly Weather Review AB - Abstract The West African monsoon (WAM) is a vital source of rainfall for the African Sahel. In addition to the agricultural benefit of its rains, it benefits public health because bacterial meningitis outbreaks end with the monsoon onset. Outbreaks occur between December and May, a period of low humidity. Knowledge of the onset of high humidity could aid in predicting where the outbreaks will cease. Therefore, this study investigates the variability of atmospheric moisture during the spring over West Africa, characterizing the sources of moisture, as well as circulation patterns and relative influences of tropical and midlatitude systems. A conceptual model of the evolution of the premonsoon period is presented. The meridional and temporal variability of surface moisture during the spring is modulated by multiscale interactions, as illustrated for the period from mid-April to early May 2009. As westward-propagating, synoptic disturbances move across West Africa, a corresponding peak occurs in the surface relative humidity. With the passage of each disturbance a new and more humid regime is established. Filtered anomalies of outgoing longwave radiation (OLR) indicate that Kelvin waves, equatorial Rossby waves, and possibly the MJO contributed to the initiation and intensification of the synoptic disturbances. During the last of the disturbances, whose passage raised the relative humidity above 40%, a critical threshold for meningitis, an extratropical cyclone also contributed to moisture influx over the Sahel. Analysis of the period 2000–09 shows the relative influences of synoptic and subseasonal circulations on the onset of high relative humidity over the Sahel during the spring. DA - 2014/9// PY - 2014/9// DO - 10.1175/mwr-d-13-00175.1 VL - 142 IS - 9 SP - 3178-3198 J2 - Mon. Wea. Rev. LA - en OP - SN - 0027-0644 1520-0493 UR - http://dx.doi.org/10.1175/mwr-d-13-00175.1 DB - Crossref ER - TY - JOUR TI - Investigation of hurricane Ivan using the coupled ocean–atmosphere–wave–sediment transport (COAWST) model AU - Zambon, Joseph B. AU - He, Ruoying AU - Warner, John C. T2 - Ocean Dynamics DA - 2014/10/12/ PY - 2014/10/12/ DO - 10.1007/s10236-014-0777-7 VL - 64 IS - 11 SP - 1535-1554 J2 - Ocean Dynamics LA - en OP - SN - 1616-7341 1616-7228 UR - http://dx.doi.org/10.1007/s10236-014-0777-7 DB - Crossref KW - Coupled modeling KW - Hurricane KW - Ocean dynamics ER - TY - JOUR TI - Influence of Functional Groups on Organic Aerosol Cloud Condensation Nucleus Activity AU - Suda, Sarah R. AU - Petters, Markus D. AU - Yeh, Geoffrey K. AU - Strollo, Christen AU - Matsunaga, Aiko AU - Faulhaber, Annelise AU - Ziemann, Paul J. AU - Prenni, Anthony J. AU - Carrico, Christian M. AU - Sullivan, Ryan C. AU - Kreidenweis, Sonia M. T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Organic aerosols in the atmosphere are composed of a wide variety of species, reflecting the multitude of sources and growth processes of these particles. Especially challenging is predicting how these particles act as cloud condensation nuclei (CCN). Previous studies have characterized the CCN efficiency for organic compounds in terms of a hygroscopicity parameter, κ. Here we extend these studies by systematically testing the influence of the number and location of molecular functional groups on the hygroscopicity of organic aerosols. Organic compounds synthesized via gas-phase and liquid-phase reactions were characterized by high-performance liquid chromatography coupled with scanning flow CCN analysis and thermal desorption particle beam mass spectrometry. These experiments quantified changes in κ with the addition of one or more functional groups to otherwise similar molecules. The increase in κ per group decreased in the following order: hydroxyl ≫ carboxyl > hydroperoxide > nitrate ≫ methylene (where nitrate and methylene produced negative effects, and hydroperoxide and nitrate groups produced the smallest absolute effects). Our results contribute to a mechanistic understanding of chemical aging and will help guide input and parametrization choices in models relying on simplified treatments such as the atomic oxygen:carbon ratio to predict the evolution of organic aerosol hygroscopicity. DA - 2014/9/2/ PY - 2014/9/2/ DO - 10.1021/es502147y VL - 48 IS - 17 SP - 10182-10190 SN - 1520-5851 ER - TY - JOUR TI - Increasing Mississippi river discharge throughout the 21st century influenced by changes in climate, land use, and atmospheric CO2 AU - Tao, Bo AU - Tian, Hanqin AU - Ren, Wei AU - Yang, Jia AU - Yang, Qichun AU - He, Ruoying AU - Cai, Weijun AU - Lohrenz, Steven T2 - GEOPHYSICAL RESEARCH LETTERS AB - Abstract Previous studies have demonstrated that changes in temperature and precipitation (hereafter climate change) would influence river discharge, but the relative importance of climate change, land use, and elevated atmospheric CO 2 have not yet been fully investigated. A process‐based projection for the Mississippi River basin suggests that river discharge would be substantially enhanced (10.7–59.8%) by the 2090s compared to the recent decade (2000s), although large discrepancies exist among different climate, atmospheric CO 2 , and land use change scenarios. Our factorial analyses further indicate that the combined effects of land use change and human‐induced atmospheric CO 2 elevation on river discharge would outweigh climate change effect under the high‐emission scenario (A2) of the Intergovernmental Panel for Climate Change, while climate change would still play the dominant role under the low‐emission scenario (B1). This study highlights the important role of anthropogenic factors in influencing future hydrological processes and water resources. DA - 2014/7/28/ PY - 2014/7/28/ DO - 10.1002/2014gl060361 VL - 41 IS - 14 SP - 4978-4986 SN - 1944-8007 ER - TY - JOUR TI - Impact of Large-Scale Atmospheric Refractive Structures on Optical Wave Propagation AU - Nunalee, Christopher G. AU - He, Ping AU - Basu, Sukanta AU - Vorontsov, Mikhail A. AU - Fiorino, Steven T. T2 - LASER COMMUNICATION AND PROPAGATION THROUGH THE ATMOSPHERE AND OCEANS III AB - Conventional techniques used to model optical wave propagation through the Earth’s atmosphere typically as- sume flow fields based on various empirical relationships. Unfortunately, these synthetic refractive index fields do not take into account the influence of transient macroscale and mesoscale (i.e. larger than turbulent microscale) atmospheric phenomena. Nevertheless, a number of atmospheric structures that are characterized by various spatial and temporal scales exist which have the potential to significantly impact refractive index fields, thereby resulting dramatic impacts on optical wave propagation characteristics. In this paper, we analyze a subset of spatio-temporal dynamics found to strongly affect optical waves propagating through these atmospheric struc- tures. Analysis of wave propagation was performed in the geometrical optics approximation using a standard ray tracing technique. Using a numerical weather prediction (NWP) approach, we simulate multiple realistic atmospheric events (e.g., island wakes, low-level jets, etc.), and estimate the associated refractivity fields prior to performing ray tracing simulations. By coupling NWP model output with ray tracing simulations, we demon- strate the ability to quantitatively assess the potential impacts of coherent atmospheric phenomena on optical ray propagation. Our results show a strong impact of spatio-temporal characteristics of the refractive index field on optical ray trajectories. Such correlations validate the effectiveness of NWP models as they offer a more comprehensive representation of atmospheric refractivity fields compared to conventional methods based on the assumption of horizontal homogeneity. DA - 2014/// PY - 2014/// DO - 10.1117/12.2063022 VL - 9224 SP - SN - 1996-756X KW - Mesoscale Modeling KW - Ray Tracing KW - Refraction KW - Turbulence ER - TY - JOUR TI - Hydroacoustic investigation of submarine landslides at West Mata volcano, Lau Basin AU - Caplan-Auerbach, J. AU - Dziak, R. P. AU - Bohnenstiehl, D. R. AU - Chadwick, W. W. AU - Lau, T. -K. T2 - GEOPHYSICAL RESEARCH LETTERS AB - Abstract Submarine landslides are an important process in volcano growth yet are rarely observed and poorly understood. We show that landslides occur frequently in association with the eruption of West Mata volcano in the NE Lau Basin. These events are identifiable in hydroacoustic data recorded between ~5 and 20 km from the volcano and may be recognized in spectrograms by the weak and strong powers at specific frequencies generated by multipathing of sound waves. The summation of direct and surface‐reflected arrivals causes interference patterns in the spectrum that change with time as the landslide propagates. Observed frequencies are consistent with propagation down the volcano's north flank in an area known to have experienced mass wasting in the past. These data allow us to estimate the distance traveled by West Mata landslides and show that they travel at average speeds of ~10–25 m/s. DA - 2014/8/28/ PY - 2014/8/28/ DO - 10.1002/2014gl060964 VL - 41 IS - 16 SP - 5927-5934 SN - 1944-8007 KW - West Mata KW - hydroacoustic KW - landslide ER - TY - PCOMM TI - High relative humidity as a trigger for widespread release of ice nuclei AU - Wright, T. P. AU - Hader, J. D. AU - McMeeking, G. R. AU - Petters, M. D. DA - 2014/// PY - 2014/// ER - TY - JOUR TI - Estimation of Optical Turbulence in the Atmospheric Surface Layer from Routine Meteorological Observations An Artificial Neural Network Approach AU - Wang, Yao AU - Basu, Sukanta T2 - LASER COMMUNICATION AND PROPAGATION THROUGH THE ATMOSPHERE AND OCEANS III AB - The focus of this paper is on the estimation of optical turbulence (commonly characterized by C2n ) near the land-surface using routinely measured meteorological variables (e.g., temperature, wind speed). We demonstrate that an artificial neural network-based approach has the potential to be effectively utilized for this purpose. We use an extensive scintillometer-based C2n dataset from a recent field experiment in Texas, USA to evaluate the accuracy of the proposed approach. DA - 2014/// PY - 2014/// DO - 10.1117/12.2063168 VL - 9224 SP - SN - 0277-786X KW - Optical Turbulence KW - Artificial Neural Network KW - Atmospheric Surface Layer ER - TY - JOUR TI - Editors' introduction: Military geoscience in the twenty-first century-A historical perspective and overview AU - Harmon, R. S. AU - McDonald, E. V. T2 - Military geosciences in the twenty-first century AB - Military geosciences are concerned with using the broad scope of the earth sciences for military purposes. These purposes range from direct support for military operations to a broad spectrum of non-combat military activities and military land management applications. Historically, the focus has been on geology and geography, but other earth science disciplines such as geophysics, remote sensing, and geocomputation have become increasingly important as a consequence of technological progress made during the final decades of the twentieth century. The eighteen chapters in this volume address the critical aspects of the role of geosciences in military undertakings by focusing on historical perspectives, geoscience for military operations, and military environmental stewardship. DA - 2014/// PY - 2014/// DO - 10.1130/2014.4122(01) VL - 22 SP - 1-10 ER - TY - JOUR TI - Current Status and Challenges in Optical Turbulence Simulations in Various Layers of the Earth's Atmosphere AU - He, Ping AU - Nunalee, Christopher G. AU - Basu, Sukanta AU - Vorontsov, Mikhail A. AU - Fiorino, Steven T. T2 - LASER COMMUNICATION AND PROPAGATION THROUGH THE ATMOSPHERE AND OCEANS III AB - In this study, we present a brief review on the existing approaches for optical turbulence estimation in various layers of the Earth’s atmosphere. The advantages and disadvantages of these approaches are also discussed. An alternative approach, based on mesoscale modeling with parameterized turbulence, is proposed and tested for the simulation of refractive index structure parameter (C2n ) in the atmospheric boundary layer. The impacts of a few atmospheric flow phenomena (e.g., low-level jets, island wake vortices, gravity waves) on optical turbulence are discussed. Consideration of diverse geographic settings (e.g., flat terrain, coastal region, ocean islands) makes this study distinct. DA - 2014/// PY - 2014/// DO - 10.1117/12.2063023 VL - 9224 SP - SN - 1996-756X KW - Atmospheric Boundary Layer KW - Mesoscale Modeling KW - Optical Turbulence Simulation ER - TY - JOUR TI - Characterizing the desert environment for Army operations AU - Gilewitch, D. A. AU - King, W. C. AU - Palka, E. J. AU - Harmon, R. S. AU - McDonald, E. V. AU - Doe, W. W. T2 - Military geosciences in the twenty-first century AB - Military geosciences are concerned with using the broad scope of the earth sciences for military purposes. These purposes range from direct support for military operations to a broad spectrum of non-combat military activities and military land management applications. Historically, the focus has been on geology and geography, but other earth science disciplines such as geophysics, remote sensing, and geocomputation have become increasingly important as a consequence of technological progress made during the final decades of the twentieth century. The eighteen chapters in this volume address the critical aspects of the role of geosciences in military undertakings by focusing on historical perspectives, geoscience for military operations, and military environmental stewardship. DA - 2014/// PY - 2014/// DO - 10.1130/2014.4122(07) VL - 22 SP - 57-68 ER - TY - JOUR TI - Air–sea interactions during strong winter extratropical storms AU - Nelson, Jill AU - He, Ruoying AU - Warner, John C. AU - Bane, John T2 - Ocean Dynamics DA - 2014/7// PY - 2014/7// DO - 10.1007/s10236-014-0745-2 VL - 64 IS - 9 SP - 1233-1246 ER - TY - JOUR TI - Aerosol microphysical impact on summertime convective precipitation in the Rocky Mountain region AU - Eidhammer, Trude AU - Barth, Mary C. AU - Petters, Markus D. AU - Wiedinmyer, Christine AU - Prenni, Anthony J. T2 - JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES AB - We present an aerosol-cloud-precipitation modeling study of convective clouds using the Weather Research and Forecasting model fully coupled with Chemistry (WRF-Chem) version 3.1.1. Comparison of the model output with measurements from a research site in the Rocky Mountains in Colorado revealed that the fraction of organics in the model is underpredicted. This is most likely due to missing processes in the aerosol module in the model version used, such as new particle formation and growth of secondary organic aerosols. When boundary conditions and domain-wide initial conditions of aerosol loading are changed in the model (factors of 0.1, 0.2, and 10 of initial aerosol mass of SO4−2, NH4+, and NO3−), the domain-wide precipitation changes by about 5%. Analysis of the model results reveals that the Rocky Mountain region and Front Range environment is not conducive for convective invigoration to play a major role, in increasing precipitation, as seen in some other studies. When localized organic aerosol emission are increased to mimic new particle formation, the resulting increased aerosol loading leads to increases in domain-wide precipitation, opposite to what is seen in the model simulations with changed boundary and initial conditions. DA - 2014/10/27/ PY - 2014/10/27/ DO - 10.1002/2014jd021883 VL - 119 IS - 20 SP - 11709-11728 SN - 2169-8996 KW - aerosols KW - cloud KW - precipitation KW - convective clouds KW - new particle formation ER - TY - JOUR TI - A Numerical Investigation of the Precipitation over Lake Victoria Basin Using a Coupled Atmosphere-Lake Limited-Area Model AU - Sun, Xia AU - Xie, Lian AU - Semazzi, Fredrick H. M. AU - Liu, Bin T2 - ADVANCES IN METEOROLOGY AB - By using a coupled atmosphere-lake model, which consists of the Weather Research and Forecasting (WRF) model and the Princeton Ocean Model (POM), the present study generated realistic lake surface temperature (LST) over Lake Victoria and revealed the prime importance of LST on the precipitation pattern over the Lake Victoria Basin (LVB). A suite of sensitivity experiments was conducted for the selection of an optimal combination of physics options including cumulus, microphysics, and planetary boundary layer schemes for simulating precipitation over the LVB. The WRF-POM coupled system made a great performance on simulating the expected LST, which is featured with eastward temperature gradient as in the real bathymetry of the lake. Under thorough examination of diagnostic analysis, a distinguished diurnal phenomenon has been unveiled. The precipitation mainly occurs during the nocturnal peak between midnight and early in the morning, which is associated with the strong land breeze circulation, when the lake temperature is warmer than the adjacent land. Further exploration of vertical velocity, surface divergence pattern, and maximum radar reflectivity confirms such conjecture. The time-longitude analysis of maximum radar reflectivity over the entire lake also shows a noticeable pattern of dominating westward propagation. DA - 2014/// PY - 2014/// DO - 10.1155/2014/960924 VL - 2014 SP - SN - 1687-9317 ER - TY - JOUR TI - pH-induced flocculation, indirect electrocoagulation, and hollow fiber filtration techniques for harvesting the saltwater microalga Dunaliella AU - Mixson, Stephanie M. AU - Stikeleather, Larry F. AU - Simmons, Otto D., III AU - Wilson, Cameron W. AU - Burkholder, JoAnn M. T2 - JOURNAL OF APPLIED PHYCOLOGY DA - 2014/8// PY - 2014/8// DO - 10.1007/s10811-013-0232-z VL - 26 IS - 4 SP - 1701-1709 SN - 1573-5176 KW - Biofuel KW - Dunaliella KW - pH-induced flocculation KW - Electrocoagulation KW - Fatty acids (FAs) KW - Hollow fiber filtration KW - Lipids ER - TY - JOUR TI - Verification of Quantitative Precipitation Reforecasts over the Southeastern United States AU - Baxter, Martin A. AU - Lackmann, Gary M. AU - Mahoney, Kelly M. AU - Workoff, Thomas E. AU - Hamill, Thomas M. T2 - WEATHER AND FORECASTING AB - Abstract NOAA’s second-generation reforecasts are approximately consistent with the operational version of the 2012 NOAA Global Ensemble Forecast System (GEFS). The reforecasts allow verification to be performed across a multidecadal time period using a static model, in contrast to verifications performed using an ever-evolving operational modeling system. This contribution examines three commonly used verification metrics for reforecasts of precipitation over the southeastern United States: equitable threat score, bias, and ranked probability skill score. Analysis of the verification metrics highlights the variation in the ability of the GEFS to predict precipitation across amount, season, forecast lead time, and location. Beyond day 5.5, there is little useful skill in quantitative precipitation forecasts (QPFs) or probabilistic QPFs. For lighter precipitation thresholds [e.g., 5 and 10 mm (24 h)−1], use of the ensemble mean adds about 10% to the forecast skill over the deterministic control. QPFs have increased in accuracy from 1985 to 2013, likely due to improvements in observations. Results of this investigation are a first step toward using the reforecast database to distinguish weather regimes that the GEFS typically predicts well from those regimes that the GEFS typically predicts poorly. DA - 2014/10// PY - 2014/10// DO - 10.1175/waf-d-14-00055.1 VL - 29 IS - 5 SP - 1199-1207 SN - 1520-0434 ER - TY - JOUR TI - Trends in particle-phase liquid water during the Southern Oxidant and Aerosol Study AU - Nguyen, T. K. V. AU - Petters, M. D. AU - Suda, S. R. AU - Guo, H. AU - Weber, R. J. AU - Carlton, A. G. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 20 SP - 10911-10930 ER - TY - JOUR TI - The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS AU - Schreck, Carl J., III AU - Knapp, Kenneth R. AU - Kossin, James P. T2 - MONTHLY WEATHER REVIEW AB - Abstract Using the International Best Track Archive for Climate Stewardship (IBTrACS), the climatology of tropical cyclones is compared between two global best track datasets: 1) the World Meteorological Organization (WMO) subset of IBTrACS (IBTrACS-WMO) and 2) a combination of data from the National Hurricane Center and the Joint Typhoon Warning Center (NHC+JTWC). Comparing the climatologies between IBTrACS-WMO and NHC+JTWC highlights some of the heterogeneities inherent in these datasets for the period of global satellite coverage 1981–2010. The results demonstrate the sensitivity of these climatologies to the choice of best track dataset. Previous studies have examined best track heterogeneities in individual regions, usually the North Atlantic and west Pacific. This study puts those regional issues into their global context. The differences between NHC+JTWC and IBTrACS-WMO are greatest in the west Pacific, where the strongest storms are substantially weaker in IBTrACS-WMO. These disparities strongly affect the global measures of tropical cyclone activity because 30% of the world’s tropical cyclones form in the west Pacific. Because JTWC employs similar procedures throughout most of the globe, the comparisons in this study highlight differences between WMO agencies. For example, NHC+JTWC has more 96-kt (~49 m s−1) storms than IBTrACS-WMO in the west Pacific but fewer in the Australian region. This discrepancy probably points to differing operational procedures between the WMO agencies in the two regions. Without better documentation of historical analysis procedures, the only way to remedy these heterogeneities will be through systematic reanalysis. DA - 2014/10// PY - 2014/10// DO - 10.1175/mwr-d-14-00021.1 VL - 142 IS - 10 SP - 3881-3899 SN - 1520-0493 ER - TY - JOUR TI - Physicochemical effects on dissolved organic matter fluorescence in natural waters AU - Osburn, C. L. AU - Del Vecchio, R. AU - Boyd, T. J. T2 - Aquatic organic matter fluorescence DA - 2014/// PY - 2014/// SP - 233-277 ER - TY - JOUR TI - Optical and chemical characterization of base-extracted particulate organic matter in coastal marine environments AU - Brym, Adeline AU - Paerl, Hans W. AU - Montgomery, Michael T. AU - Handsel, Lauren T. AU - Ziervogel, Kai AU - Osburn, Christopher L. T2 - MARINE CHEMISTRY AB - Absorbance and fluorescence measurements were measured on base-extracted particulate organic matter (BEPOM) to examine POM biogeochemistry in coastal marine environments. BEPOM trends from August 2011–September 2012 in the Neuse River Estuary (NRE) were compared against single sampling events in Charleston Harbor (CHS) and the inner Louisiana–Texas Shelf of the Gulf of Mexico (GOM) in July 2011 and July 2012, respectively. Spectral slope values, S275–295, and the ratio of spectral slopes, SR values, were mainly influenced by distinct structure in the UV-B region of BEPOM absorption spectra, which was similar to prior laboratory work on autochthonous, planktonic sources of chromophoric dissolved organic matter (CDOM). A PARAFAC model with five components was fit to BEPOM excitation–emission matrix (EEM) fluorescence data. Excitation and emission spectra of the five components were similar to those found for dissolved organic matter (DOM) in other coastal environments, with two components attributed to planktonic sources and two components attributed to terrestrial (humic) sources. A fifth component was attributed to microbial humic substances. Principle components analysis of PARAFAC results separated autochthonous, planktonic components from allochthonous, terrestrial components and explained > 70% of the variance in the data. Surface water stable carbon isotope (δ13C) values of BEPOM from the NRE and CHS ranged from − 29 to − 23‰, with most enriched values occurring synchronous with high Chl-a concentrations, and indicating that enriched δ13C values in BEPOM reflected a planktonic source. Notably, δ13C-BEPOM values for the GOM shelf below 50 m water depth were depleted (<− 30‰), and a mixing model indicated that 30–40% of the POM could originate from methanic carbon. BEPOM absorption and fluorescence results suggested a planktonic POM as a source of CDOM in coastal marine environments. DA - 2014/5/20/ PY - 2014/5/20/ DO - 10.1016/j.marchem.2014.03.006 VL - 162 SP - 96-113 SN - 1872-7581 KW - POM KW - Absorption KW - Fluorescence KW - PARAFAC KW - Carbon stable isotopes ER - TY - JOUR TI - OCEAN-CLOUD-ATMOSPHERELAND INTERACTIONS IN THE SOUTHEASTERN PACIFIC AU - Mechoso, C. R. AU - Wood, R. AU - Weller, R. AU - Bretherton, C. S. AU - Clarke, A. D. AU - Coe, H. AU - Fairall, C. AU - Farrar, J. T. AU - Feingold, G. AU - Garreaud, R. AU - Grados, C. AU - McWilliams, J. AU - Szoeke, S. P. AU - Yuter, S. E. AU - Zuidema, P. T2 - BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY AB - The present paper describes the Variability of the American Monsoon Systems (VAMOS) Ocean–Cloud–Atmosphere–Land Study (VOCALS), an international research program focused on the improved understanding and modeling of the southeastern Pacific (SEP) climate system on diurnal to interannual time scales. In the framework of the SEP climate, VOCALS has two fundamental objectives: 1) improved simulations by coupled atmosphere–ocean general circulation models (CGCMs), with an emphasis on reducing systematic errors in the region; and 2) improved estimates of the indirect effects of aerosols on low clouds and climate, with an emphasis on the more precise quantification of those effects. VOCALS major scientific activities are outlined, and selected achievements are highlighted. Activities described include monitoring in the region, a large international field campaign (the VOCALS Regional Experiment), and two model assessments. The program has already produced significant advances in the understanding of major issues in the SEP: the coastal circulation and the diurnal cycle, the ocean heat budget, factors controlling precipitation and formation of pockets of open cells in stratocumulus decks, aerosol impacts on clouds, and estimation of the first aerosol indirect effect. The paper concludes with a brief presentation on VOCALS contributions to community capacity building before a summary of scientific findings and remaining questions. DA - 2014/3// PY - 2014/3// DO - 10.1175/bams-d-11-00246.1 VL - 95 IS - 3 SP - 357-375 SN - 1520-0477 ER - TY - JOUR TI - Mesoscale modeling of coastal low-level jets: implications for offshore wind resource estimation AU - Nunalee, Christopher G. AU - Basu, Sukanta T2 - WIND ENERGY AB - Detailed and reliable spatiotemporal characterizations of turbine hub height wind fields over coastal and offshore regions are becoming imperative for the global wind energy industry. Contemporary wind resource assessment frameworks incorporate diverse multiscale prognostic models (commonly known as mesoscale models) to dynamically downscale global-scale atmospheric fields to regional-scale (i.e., spatial and temporal resolutions of a few kilometers and a few minutes, respectively). These high-resolution model solutions aim at depicting the expected wind behavior (e.g., wind shear, wind veering and topographically induced flow accelerations) at a particular location. Coastal and offshore regions considered viable for wind power production are also known to possess complex atmospheric flow phenomena (including, but not limited to, coastal low-level jets (LLJs), internal boundary layers and land breeze–sea breeze circulations). Unfortunately, the capabilities of the new-generation mesoscale models in realistically capturing these diverse flow phenomena are not well documented in the literature. To partially fill this knowledge gap, in this paper, we have evaluated the performance of the Weather Research and Forecasting model, a state-of-the-art mesoscale model, in simulating a series of coastal LLJs. Using observational data sources we explore the importance of coastal LLJs for offshore wind resource estimation along with the capacity to which they can be numerically simulated. We observe model solutions to demonstrate strong sensitivities with respect to planetary boundary layer parameterization and initialization conditions. These sensitivities are found to be responsible for variability in AEP estimates by a factor of two. Copyright © 2013 John Wiley & Sons, Ltd. DA - 2014/8// PY - 2014/8// DO - 10.1002/we.1628 VL - 17 IS - 8 SP - 1199-1216 SN - 1099-1824 KW - atmospheric boundary layer KW - numerical weather prediction KW - offshore wind turbine KW - turbulence modeling KW - wind shear ER - TY - JOUR TI - Deepwater Horizon Oil in Gulf of Mexico Waters after 2 Years: Transformation into the Dissolved Organic Matter Pool AU - Bianchi, Thomas S. AU - Osburn, Christopher AU - Shields, Michael R. AU - Yvon-Lewis, Shari AU - Young, Jordan AU - Guo, Laodong AU - Zhou, Zhengzhen T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Recent work has shown the presence of anomalous dissolved organic matter (DOM), with high optical yields, in deep waters 15 months after the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico (GOM). Here, we continue to use the fluorescence excitation-emission matrix (EEM) technique coupled with parallel factor analysis (PARAFAC) modeling, measurements of bulk organic carbon, dissolved inorganic carbon (DIC), oil indices, and other optical properties to examine the chemical evolution and transformation of oil components derived from the DWH in the water column of the GOM. Seawater samples were collected from the GOM during July 2012, 2 years after the oil spill. This study shows that, while dissolved organic carbon (DOC) values have decreased since just after the DWH spill, they remain higher at some stations than typical deep-water values for the GOM. Moreover, we continue to observe fluorescent DOM components in deep waters, similar to those of degraded oil observed in lab and field experiments, which suggest that oil-related fluorescence signatures, as part of the DOM pool, have persisted for 2 years in the deep waters. This supports the notion that some oil-derived chromophoric dissolved organic matter (CDOM) components could still be identified in deep waters after 2 years of degradation, which is further supported by the lower DIC and partial pressure of carbon dioxide (pCO2) associated with greater amounts of these oil-derived components in deep waters, assuming microbial activity on DOM in the current water masses is only the controlling factor of DIC and pCO2 concentrations. DA - 2014/8/19/ PY - 2014/8/19/ DO - 10.1021/es501547b VL - 48 IS - 16 SP - 9288-9297 SN - 1520-5851 ER - TY - JOUR TI - Data assimilative modeling investigation of Gulf Stream Warm Core Ring interaction with continental shelf and slope circulation AU - Chen, Ke AU - He, Ruoying AU - Powell, Brian S. AU - Gawarkiewicz, Glen G. AU - Moore, Andrew M. AU - Arango, Hernan G. T2 - JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS AB - Abstract A data assimilative ocean circulation model is used to hindcast the interaction between a large Gulf Stream Warm Core Ring (WCR) with the Mid‐Atlantic Bight (MAB) shelf and slope circulation. Using the recently developed Incremental Strong constraint 4D Variational (I4D‐Var) data assimilation algorithm, the model assimilates mapped satellite sea surface height (SSH), sea surface temperature (SST), in situ temperature, and salinity profiles measured by expendable bathythermograph, Argo floats, shipboard CTD casts, and glider transects. Model validations against independent hydrographic data show 60% and 57% error reductions in temperature and salinity, respectively. The WCR significantly changed MAB continental slope and shelf circulation. The mean cross‐shelf transport induced by the WCR is estimated to be 0.28 Sv offshore, balancing the mean along‐shelf transport by the shelfbreak jet. Large heat/salt fluxes with peak values of 8900 W m −2 /4 × 10 −4 kg m −2 s −1 are found when the WCR was impinging upon the shelfbreak. Vorticity analysis reveals the nonlinear advection term, as well as the residual of joint effect of baroclinicity and bottom relief (JEBAR) and advection of potential vorticity (APV) play important roles in controlling the variability of the eddy vorticity. DA - 2014/9// PY - 2014/9// DO - 10.1002/2014jc009898 VL - 119 IS - 9 SP - 5968-5991 SN - 2169-9291 KW - Gulf Stream KW - Warm Core Ring KW - shelf circulation KW - data assimilation ER - TY - JOUR TI - Antarctic icebergs: A significant natural ocean sound source in the Southern Hemisphere AU - Matsumoto, H. AU - Bohnenstiehl, D. R. AU - Tournadre, J. AU - Dziak, R. P. AU - Haxel, J. H. AU - Lau, T. K. A. AU - Fowler, M. AU - Salo, S. A. T2 - Geochemistry, Geophysics, Geosystems AB - Abstract In late 2007, two massive icebergs, C19a and B15a, drifted into open water and slowly disintegrated in the southernmost Pacific Ocean. Archived acoustic records show that the high‐intensity underwater sounds accompanying this breakup increased ocean noise levels at mid‐to‐equatorial latitudes over a period of ∼1.5 years. More typically, seasonal variations in ocean noise, which are characterized by austral summer‐highs and winter‐lows, appear to be modulated by the annual cycle of Antarctic iceberg drift and subsequent disintegration. This seasonal pattern is observed in all three Oceans of the Southern Hemisphere. The life cycle of Antarctic icebergs affects not only marine ecosystem but also the sound environment in far‐reaching areas and must be accounted for in any effort to isolate anthropogenic or climate‐induced noise contributions to the ocean soundscape. DA - 2014/// PY - 2014/// DO - 10.1002/2014gc005454 VL - 15 IS - 8 SP - 3448-3458 ER - TY - JOUR TI - A red tide of Alexandrium fundyense in the Gulf of Maine AU - McGillicuddy, D. J., Jr. AU - Brosnahan, M. L. AU - Couture, D. A. AU - He, R. AU - Keafer, B. A. AU - Manning, J. P. AU - Martin, J. L. AU - Pilskaln, C. H. AU - Townsend, D. W. AU - Anderson, D. M. T2 - DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY AB - In early July 2009, an unusually high concentration of the toxic dinoflagellate Alexandrium fundyense occurred in the western Gulf of Maine, causing surface waters to appear reddish brown to the human eye. The discolored water appeared to be the southern terminus of a large-scale event that caused shellfish toxicity along the entire coast of Maine to the Canadian border. Rapid-response shipboard sampling efforts together with satellite data suggest the water discoloration in the western Gulf of Maine was a highly ephemeral feature of less than two weeks in duration. Flow cytometric analysis of surface samples from the red water indicated the population was undergoing sexual reproduction. Cyst fluxes downstream of the discolored water were the highest ever measured in the Gulf of Maine, and a large deposit of new cysts was observed that fall. Although the mechanisms causing this event remain unknown, its timing coincided with an anomalous period of downwelling-favorable winds that could have played a role in aggregating upward-swimming cells. Regardless of the underlying causes, this event highlights the importance of short-term episodic phenomena on regional population dynamics of A. fundyense. DA - 2014/5// PY - 2014/5// DO - 10.1016/j.dsr2.2013.05.011 VL - 103 SP - 174-184 SN - 1879-0100 KW - Phytoplankton KW - Population dynamics KW - Red tides KW - Cysts KW - Paralytic shellfish poisoning KW - USA KW - Gulf of Maine ER - TY - JOUR TI - 3-D agricultural air quality modeling: Impacts of NH3/H2S gas-phase reactions and bi-directional exchange of NH3 AU - Wang, Kai AU - Zhang, Yang T2 - ATMOSPHERIC ENVIRONMENT AB - Abstract Accurately simulating the transport and fate of reduced nitrogen (NHx = ammonia (NH3) + ammonium (NH4+))- and sulfur-containing compounds emitted from agricultural activities represents a major challenge in agricultural air quality modeling. In this study, the Community Multiscale Air Quality (CMAQ) modeling system is further developed and improved by implementing 22 ammonia (NH3)/hydrogen sulfide (H2S) related gas-phase reactions and adjusting a few key parameters (e.g., emission potential) for bi-directional exchange of NH3 fluxes. Several simulations are conducted over the eastern U.S. domain at a 12-km horizontal resolution for January and July 2002 to examine the impacts of those improved treatments on air quality. The 5th generation mesoscale model (MM5) and CMAQ predict an overall satisfactory and consistent performance with previous modeling studies, especially for 2-m temperature, 2-m relative humidity, ozone (O3), and fine particulate matter (PM2.5). High model biases exist for precipitation in July and also dry/wet depositions. The updated model treatments contribute to O3, NHx, and PM2.5 by up to 0.4 ppb, 1.0 μg m−3, and 1.0 μg m−3 in January, respectively, and reduce O3 by up to 0.8 ppb and contribute to NHx and PM2.5 by up to 1.2 and 1.1 μg m−3 in July, respectively. The spatial distributions of O3 in both months and sulfur dioxide (SO2) in January are mainly affected by inline dry deposition velocity calculation. The spatial distributions of SO2 and sulfate (SO42−) in July are affected by both inline dry deposition velocity and NH3/H2S reactions. The variation trends of NH3, NHx, ammonium nitrate (NH4NO3), PM2.5 and total nitrogen (TN) are predominated by bi-directional exchange of NH3 fluxes. Uncertainties of NH3 emission potentials and empirical constants used in the bi-directional exchange scheme may significantly affect the concentrations of NHx and PM2.5, indicating that a more accurate and explicit treatment for those parameters should be considered in the future work. DA - 2014/12// PY - 2014/12// DO - 10.1016/j.atmosenv.2014.09.010 VL - 98 SP - 554-570 SN - 1873-2844 KW - Agriculture KW - Air quality KW - Reduced nitrogen and sulfur KW - NH3/H2S reactions KW - Bi-directional flux KW - CMAQ ER - TY - JOUR TI - Warm streaks in the US temperature record: What are the chances? AU - Craigmile, P. F. AU - Guttorp, P. AU - Lund, R. AU - Smith, R. L. AU - Thorne, P. AU - Arndt, D. T2 - Journal of Geophysical Research-Atmospheres DA - 2014/// PY - 2014/// VL - 119 IS - 10 SP - 5757-5766 ER - TY - JOUR TI - Twentieth century Atlantic meridional overturning circulation as an indicator of global ocean multidecadal variability: influences on sea level anomalies and small pelagic fishery synchronies AU - Kamykowski, Daniel T2 - ICES JOURNAL OF MARINE SCIENCE AB - Abstract The Atlantic dipole phosphate utilization (ADPU) index, derived through statistical conversion of 20th century Atlantic basin subpolar sea surface temperatures, is used as a fingerprint of Atlantic meridional overturning circulation (AMOC) variability and as an indicator of global Meridional Overturing Circulation (MOC) variability. ADPU index correlations with differences in sea level anomalies (SLAs) between Canada and the UK and across the Isthmus of Panama demonstrate intrabasin and interbasin associations with MOC variability. Cross-correlation analyses of ADPU index, SLAs, and sardine (S) and anchovy (A) catch differences [S −A] (normalized sardine catch minus normalized anchovy catch) confirm strong correlations between ADPU and [S −A] off Japan, California, Peru and Southwest Africa (Benguela). Statistically significant cross correlations also exist between the ADPU index and SLAs for Japan, California, Peru and Benguela, and for SLAs and [S − A] for Japan, California and Peru, but the short time-series lengths compared with the length of the multidecadal cycle limit the interpretation of the observed lead-lags. Though correlation is not causality, the correlation analyses developed here are useful in support of hypothesis generation. The proposed hypothesis to explain the observed small pelagic fishery synchronies asserts: (i) ocean bathymetry and continental distributions interact with multidecadal variations in MOC strength that occur along the conceptual global conveyor belt to generate changes in global oceanic planetary waves and mesoscale eddies that propagate through the world ocean; (ii) each small pelagic fishery region has a unique spatial relationship with pertinent oceanic planetary wave and mesoscale eddy source regions that affect the timing and strength of the waves and eddies that influence the nearby boundary current; (iii) synchronous changes or phasing among global fisheries depend on how and when MOC variability mediated by oceanic planetary waves and mesoscale eddies reaches each fishery region; (iv) oceanic planetary waves and/or mesoscale eddies influence the strength or meandering of the boundary current adjacent to a small pelagic fishery region to change local SLAs and environmental conditions to favour sardine or anchovy populations at different times. DA - 2014/// PY - 2014/// DO - 10.1093/icesjms/fst165 VL - 71 IS - 3 SP - 455-468 SN - 1095-9289 KW - AMOC KW - anchovy fisheries KW - Kelvin waves KW - mesoscale eddies KW - MOC KW - planetary waves KW - Rossby waves KW - sardine fisheries KW - THC ER - TY - JOUR TI - The role of mixotrophic protists in the biological carbon pump AU - Mitra, A. AU - Flynn, K. J. AU - Burkholder, J. M. AU - Berge, T. AU - Calbet, A. AU - Raven, J. A. AU - Graneli, E. AU - Glibert, P. M. AU - Hansen, P. J. AU - Stoecker, D. K. AU - Thingstad, F. AU - Tillmann, U. AU - Vage, S. AU - Wilken, S. AU - Zubkov, M. V. T2 - BIOGEOSCIENCES AB - Abstract. The traditional view of the planktonic food web describes consumption of inorganic nutrients by photoautotrophic phytoplankton, which in turn supports zooplankton and ultimately higher trophic levels. Pathways centred on bacteria provide mechanisms for nutrient recycling. This structure lies at the foundation of most models used to explore biogeochemical cycling, functioning of the biological pump, and the impact of climate change on these processes. We suggest an alternative new paradigm, which sees the bulk of the base of this food web supported by protist plankton communities that are mixotrophic – combining phototrophy and phagotrophy within a single cell. The photoautotrophic eukaryotic plankton and their heterotrophic microzooplankton grazers dominate only during the developmental phases of ecosystems (e.g. spring bloom in temperate systems). With their flexible nutrition, mixotrophic protists dominate in more-mature systems (e.g. temperate summer, established eutrophic systems and oligotrophic systems); the more-stable water columns suggested under climate change may also be expected to favour these mixotrophs. We explore how such a predominantly mixotrophic structure affects microbial trophic dynamics and the biological pump. The mixotroph-dominated structure differs fundamentally in its flow of energy and nutrients, with a shortened and potentially more efficient chain from nutrient regeneration to primary production. Furthermore, mixotrophy enables a direct conduit for the support of primary production from bacterial production. We show how the exclusion of an explicit mixotrophic component in studies of the pelagic microbial communities leads to a failure to capture the true dynamics of the carbon flow. In order to prevent a misinterpretation of the full implications of climate change upon biogeochemical cycling and the functioning of the biological pump, we recommend inclusion of multi-nutrient mixotroph models within ecosystem studies. DA - 2014/// PY - 2014/// DO - 10.5194/bg-11-995-2014 VL - 11 IS - 4 SP - 995-1005 SN - 1726-4189 ER - TY - JOUR TI - The Role of Stratospheric Polar Vortex Breakdown in Southern Hemisphere Climate Trends AU - Sun, Lantao AU - Chen, Gang AU - Robinson, Walter A. T2 - JOURNAL OF THE ATMOSPHERIC SCIENCES AB - Abstract This paper investigates the connection between the delay in the final breakdown of the stratospheric polar vortex, the stratospheric final warming (SFW), and Southern Hemisphere climate trends. The authors first analyze Interim European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-Interim) and three climate model outputs with different climate forcings. Climate trends appear when there is a delay in the timing of SFWs. When regressed onto the SFW dates (which reflect the anomaly when the SFW is delayed for one standard deviation of its onset dates), the anomaly pattern bears a resemblance to the observed climate trends, for all the model outputs, even without any trends. This suggests that the stratospheric and tropospheric circulations are organized by the timing of SFWs in both the interannual time scale and climate trends because of external forcings. The authors further explore the role of the SFW using a simplified dynamical model in which the ozone depletion is mimicked by a springtime polar stratospheric cooling. The responses of zonal-mean atmospheric circulation, including zonal wind, temperature, and poleward edge of the Hadley cell and the Ferrel cell, are similar to the observed climate trends. The authors divide the years into those in which the SFW is delayed and those in which it is not. The responses for the years in which the SFW is delayed are very similar to the overall response, while the stratosphere is only characterized by the localized cooling for those years in which the SFW is not delayed, with no subsequent downward influence into the troposphere. This suggests that, in order to affect the troposphere, ozone depletion must first delay the SFW so as to induce a deep response in planetary wave drag and the associated eddy-driven circulation. DA - 2014/7// PY - 2014/7// DO - 10.1175/jas-d-13-0290.1 VL - 71 IS - 7 SP - 2335-2353 SN - 1520-0469 UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000337920200004&KeyUID=WOS:000337920200004 ER - TY - JOUR TI - Seasonal and interannual variability in Gulf of Maine hydrodynamics: 2002-2011 AU - Li, Yizhen AU - He, Ruoying AU - McGillicuddy, Dennis J., Jr. T2 - DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY AB - In situ observations including long-term moored meteorological and oceanographic measurements and multi-year gulf-wide ship survey data are used to quantify interannual variability of surface wind, river runoff, and hydrographic conditions in the Gulf of Maine during summers 2002-2011. The cumulative upwelling index shows that upwelling (downwelling)-favorable wind conditions were most persistent in 2010 (2005) over the 10-year study period. River discharge was highest in 2005; peak runoff occurred in early April in 2010 as opposed to late April to middle May in other years. Moored time series show that coastal water temperature was 0.5-2 °C warmer than average in summer 2010, and about 2 °C colder than average in 2004. Coastal salinity in April 2010 was the lowest in the 10-year study period. Both moored Acoustic Doppler Current Profiler (ADCP) current measurements and dynamic height/geostrophic velocity calculations based on gulf-wide ship survey data show May-June 2010 had one of the weakest alongshore transports in the western Gulf of Maine during the 10-year study period, likely associated with intrusions of warm slope water and fresher-than-usual Scotian Shelf water. Comparisons of coastal currents to the Paralytic Shellfish Poisoning (PSP) closure maps resulting from A. fundyense blooms suggest a linkage between alongshore transport and the downstream extent of toxicity. DA - 2014/5// PY - 2014/5// DO - 10.1016/j.dsr2.2013.03.001 VL - 103 SP - 210-222 SN - 1879-0100 KW - Gulf of Maine KW - Upwelling index KW - River discharge KW - Hydrography KW - Interannual variability ER - TY - JOUR TI - Patterns and processes of habitat-specific demographic variability in exploited marine species AU - Vasconcelos, Rita P. AU - Eggleston, David B. AU - Le Pape, Olivier AU - Tulp, Ingrid T2 - ICES JOURNAL OF MARINE SCIENCE AB - Abstract Population dynamics are governed by four demographic rates: births, deaths, immigration, and emigration. Variation in these rates and processes underlying such variation can be used to prioritize habitat conservation and restoration as well as to parameterize models that predict habitat-specific effects on population dynamics. The current understanding of patterns of habitat-specific demographic variability in exploited marine species, as well as processes underlying these patterns, was reviewed. We describe patterns of (i) habitat-specific density, followed by ontogenetic changes in habitat use, such as (ii) immigration (i.e. use as a settlement habitat) and (iii) emigration (i.e. use as a habitat for secondary dispersal to and from), and demographic rates such as (iv) growth, and (v) mortality. Despite the importance of coastal habitats for fish and invertebrate species and the vulnerability of these habitats to human impacts, there was ambiguous evidence on their role in driving of population dynamics. Roughly 63% of the studies were descriptive, 21% experimental, and 11% used a combination of descriptive and experimental approaches, whereas 5% used meta-analyses. Habitat-specific density was the most common pattern quantified, followed by growth and mortality, with relatively few examples of studies of habitat-specific larval settlement. There were many examples of the influence of coastal habitats on survival, growth, and movement, especially at young stages, and there was an emerging focus on the effects of habitat degradation on demographic rates. There needs to be an increased effort on quantifying habitat-specific demographic rates and integrating these to better predict the effects of coastal habitats on the dynamics of exploited marine populations. DA - 2014/// PY - 2014/// DO - 10.1093/icesjms/fst136 VL - 71 IS - 3 SP - 638-647 SN - 1095-9289 KW - coastal area KW - demographic rates KW - fish KW - habitat KW - invertebrates KW - population dynamics ER - TY - JOUR TI - Mapping Asian anthropogenic emissions of non-methane volatile organic compounds to multiple chemical mechanisms AU - Li, M. AU - Zhang, Q. AU - Streets, D. G. AU - He, K. B. AU - Cheng, Y. F. AU - Emmons, L. K. AU - Huo, H. AU - Kang, S. C. AU - Lu, Z. AU - Shao, M. AU - Su, H. AU - Yu, X. AU - Zhang, Y. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 11 SP - 5617-5638 ER - TY - JOUR TI - Investigation of aerosol indirect effects using a cumulus microphysics parameterization in a regional climate model AU - Lim, Kyo-Sun Sunny AU - Fan, Jiwen AU - Leung, Ruby AU - Ma, Po-Lun AU - Singh, Balwinder AU - Zhao, Chun AU - Zhang, Yang AU - Zhang, Guang AU - Song, Xiaoliang T2 - JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES AB - Abstract A new Zhang and McFarlane (ZM) cumulus scheme includes a two‐moment cloud microphysics parameterization for convective clouds. This allows aerosol effects to be investigated more comprehensively by linking aerosols with microphysical processes in both stratiform clouds that are explicitly resolved and convective clouds that are parameterized in climate models. This new scheme is implemented in the Weather Research and Forecasting model, coupled with the physics and aerosol packages from the Community Atmospheric Model version 5. A case of July 2008 during the East Asian summer monsoon is selected to evaluate the performance of the new ZM and to investigate aerosol effects on monsoon precipitation. The precipitation and radiative fluxes simulated by the new ZM show a better agreement with observations compared to simulations with the original ZM that does not include convective cloud microphysics and aerosol‐convective cloud interactions. Detailed analysis suggests that an increase in detrained cloud water and ice mass by the new ZM is responsible for this improvement. Aerosol impacts on cloud properties, precipitation, and radiation are examined by reducing the primary aerosols and anthropogenic emissions to 30% of those in the present (polluted) condition. The simulated surface precipitation is reduced by 9.8% from clean to polluted environment, and the reduction is less significant when microphysics processes are excluded from the cumulus clouds. Cloud fraction is reduced by the increased aerosols due to suppressed convection, except during some heavy precipitation periods when cloud fraction, cloud top height, and rain rate are increased due to enhanced convection. DA - 2014/1/27/ PY - 2014/1/27/ DO - 10.1002/2013jd020958 VL - 119 IS - 2 SP - 906-926 SN - 2169-8996 ER - TY - JOUR TI - Instability Characteristics of Radar-Derived Mesoscale Organization Modes within Cool-Season Precipitation near Portland, Oregon* AU - Cunningham, Jeffrey G. AU - Yuter, Sandra E. T2 - MONTHLY WEATHER REVIEW AB - Abstract The instability characteristics associated with different radar-derived mesoscale organization modes are examined using six cool seasons of operational scanning radar data near Portland, Oregon, and operational sounding data from Salem, Oregon. Additionally, several years of Microwave Rain Radar Ka-band vertically pointing radar data from Portland and Merwin, Washington, are used to characterize the nature and occurrence of generating cells and fall streaks. The combination of a new metric, convective-stratiform intermittency, with the classification of radar reflectivity maps into convective and stratiform precipitation types was applied to periods when the freezing level was &gt;1.4-km altitude. This method distinguishes periods with embedded convective within stratiform mesoscale organization from those that were mostly convective or mostly stratiform. Mesoscale organization occurs in a continuum of states with predominantly stratiform structure occurring most frequently. Generating cells in the snow layer are common in cool-season storms and are primarily associated with potential instability aloft. For mostly stratiform and embedded convective within stratiform 3-h periods, the vertically pointing radar data showed nearly ubiquitous fall streaks in the snow layer originating above 3-km altitude. Stronger generating cells enhanced reflectivity in the rain layer consistent with a seeder mechanism. Stronger generating cells were more common during embedded convection within stratiform than in mostly stratiform periods. Nearly all embedded periods have active or latent (potential) instability. Hydrostatic instability more typically occurred at higher altitudes for embedded convective within stratiform periods compared to mostly convective periods. The occurrence of vertical wind shear instability was primary below 2-km altitude and was not typically associated with levels with generating cells. DA - 2014/5// PY - 2014/5// DO - 10.1175/mwr-d-13-00133.1 VL - 142 IS - 5 SP - 1738-1757 SN - 1520-0493 KW - Storm environments KW - Radiosonde observations KW - Radars/Radar observations KW - Mesoscale processes KW - Orographic effects KW - Mesoscale systems ER - TY - JOUR TI - Impacts of updated emission inventories on source apportionment of fine particle and ozone over the southeastern US AU - Zhang, Yang AU - Wang, Wei AU - Wu, Shiang-Yuh AU - Wang, Kai AU - Minoura, Hiroaki AU - Wang, Zifa T2 - ATMOSPHERIC ENVIRONMENT AB - As the U.S. Environmental Protection Agency updates the National Emission Inventory (NEI), the source contributions (SC) of major source sectors to major pollutants based on source apportionment techniques should be periodically reassessed to reflect changes in SCs due to changes in emissions. This work assesses emission updates from the 1999 NEI version 2 (NEI99v2) and the 2005 NEI (NEI05) and the resulting differences in SCs using the two inventories. Large differences exist in the emissions of nitrogen oxide, formaldehyde, ammonia, terpene, and primary PM2.5 between NEI99v2 and NEI05. Differences in emissions lead to differences in model performance and source appointment. SCs of ten major source categories to fine particulate matter (PM2.5) are estimated using the Community Multiscale Air Quality modeling system with the Brute Force Method (CMAQ/BFM) andNEI05and compared with those obtained previously using CMAQ/BFM with NEI99v2. In January, compared to CMAQ/BFM (NEI99v2), CMAQ/BFM (NEI05) shows that miscellaneous areas, biomass burning, and coal combustion remain the top three contributors to PM2.5 but with different ranking and higher SCs (17.7%, 16.0%, and 14.1% for NEI05 vs. 11.8%, 13.7%, and 10.8% for NEI99v2, respectively). In July, coal combustion, miscellaneous areas, and industrial processes remain the top three with higher SCs (41.9%, 14.1%, and 8.8% for NEI05 vs.30.8%, 8.9%, and 6.9% for NEI99v2, respectively). Those changes in SCs are attributed to increased primary PM2.5 (PPM) emissions in NEI05 and increases in relative contributions of miscellaneous areas and coal combustion to the emissions of PPM, NH3, and SO2.SCs from diesel and gasoline vehicles decrease in both months, due to decreased contributions of gasoline vehicles to SO2 and NH3 emissions and those of diesel vehicles to NOx and PPM emissions. Compared with CMAQ/BFM (NEI99v2), SCs from other combustion and biomass burning are higher in Florida, due to substantial increases in formaldehyde and PPM emissions in NEI05, resulting from higher wildfire emissions and state emission updates. SCs from industrial processes increase and those from diesel and gasoline vehicles decrease in urban areas. SCs of O3 from most sources in both months increase due to a large increase in their contributions to NOx emissions, except for diesel vehicles in July, which decreases over domainwide due to a relative decrease in NOx emissions. These results provide valuable information for policy makers to formulate and adjust emission control strategies as the NEI is continuously updated. DA - 2014/5// PY - 2014/5// DO - 10.1016/j.atmosenv.2014.01.035 VL - 88 SP - 133-154 SN - 1873-2844 KW - Source apportionment KW - CMAQ KW - Brute force sensitivity analysis KW - PM2.5 KW - O-3 KW - National Emission Inventory ER - TY - JOUR TI - Impacts of future climate and emission changes on US air quality AU - Penrod, Ashley AU - Zhang, Yang AU - Wang, Kai AU - Wu, Shiang-Yuh AU - Leung, L. Ruby T2 - ATMOSPHERIC ENVIRONMENT AB - Changes in climate and emissions will affect future air quality. In this work, simulations of regional air quality during current (2001–2005) and future (2026–2030) winter and summer are conducted with the newly released CMAQ version 5.0 to examine the impacts of simulated future climate and anthropogenic emission projections on air quality over the U.S. Current meteorological and chemical predictions are evaluated against observations to assess the model's capability in reproducing the seasonal differences. WRF and CMAQ capture the overall observational spatial patterns and seasonal differences. Biases in model predictions are attributed to uncertainties in emissions, boundary conditions, and limitations in model physical and chemical treatments as well as the use of a coarse grid resolution. Increased temperatures (up to 3.18 °C) and decreased ventilation (up to 157 m in planetary boundary layer height) are found in both future winter and summer, with more prominent changes in winter. Increases in future temperatures result in increased isoprene and terpene emissions in winter and summer, driving the increase in maximum 8-h average O3 (up to 5.0 ppb) over the eastern U.S. in winter while decreases in NOx emissions drive the decrease in O3 over most of the U.S. in summer. Future PM2.5 concentrations in winter and summer and many of its components decrease due to decreases in primary anthropogenic emissions and the concentrations of secondary anthropogenic pollutants as well as increased precipitation in winter. Future winter and summer dry and wet deposition fluxes are spatially variable and increase with decreasing surface resistance and precipitation, respectively. They decrease with a decrease in ambient particulate concentrations. Anthropogenic emissions play a more important role in summer than in winter for future O3 and PM2.5 levels, with a dominance of the effects of significant emission reductions over those of climate change on future PM2.5 levels. DA - 2014/6// PY - 2014/6// DO - 10.1016/j.atmosenv.2014.01.001 VL - 89 SP - 533-547 SN - 1873-2844 KW - Future climate change KW - Emissions KW - Air quality KW - CMAQ KW - WRF KW - Model evaluation ER - TY - JOUR TI - Global emission projections for the transportation sector using dynamic technology modeling AU - Yan, F. AU - Winijkul, E. AU - Streets, D. G. AU - Lu, Z. AU - Bond, T. C. AU - Zhang, Y. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 11 SP - 5709-5733 ER - TY - JOUR TI - Flight performance of the largest volant bird AU - Ksepka, D. T. T2 - Proceedings of the National Academy of Sciences of the United States of America DA - 2014/// PY - 2014/// VL - 111 IS - 29 SP - 10624-10629 ER - TY - JOUR TI - Estuarine soundscapes: distinct acoustic characteristics of oyster reefs compared to soft-bottom habitats AU - Lillis, Ashlee AU - Eggleston, David B. AU - Bohnenstiehl, DelWayne R. T2 - MARINE ECOLOGY PROGRESS SERIES AB - MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 505:1-17 (2014) - DOI: https://doi.org/10.3354/meps10805 FEATURE ARTICLE Estuarine soundscapes: distinct acoustic characteristics of oyster reefs compared to soft-bottom habitats Ashlee Lillis*, David B. Eggleston, DelWayne R. Bohnenstiehl Department of Marine, Earth & Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695-8208, USA *Corresponding author: aslillis@ncsu.edu ABSTRACT: Different types of benthic habitats likely produce distinct soundscapes due to differences in the physical and biological contributors to ambient sound. Despite their potential importance to ecological processes such as larval settlement, the soundscapes of most coastal and estuarine habitats have not been characterized. We investigated whether an estuarine soundscape is a reliable indicator of habitat type by measuring the sounds of oyster reefs and nearby off-reef soft-bottom areas in Pamlico Sound, North Carolina, USA. Acoustic sampling in 3 areas across the estuary revealed distinct acoustic patterns in oyster reef habitats compared to surrounding off-reef areas, with reef soundscapes dominated by snapping shrimp sounds and the vocalizations of reef-dwelling fish species. Compared to soft-bottom habitat, oyster reefs had significantly higher sound pressure levels in the 2-23 kHz frequency band and higher acoustic diversity index values at each concurrent sampling event. Spectral differences between adjacent reef/off-reef habitats were present throughout the summer and fall sampling season and across 2 sampling years, but the acoustic signal strength differed between reef sites. Passive sound propagation surveys found that the distinct acoustic characteristics of oyster reefs within the 2-23 kHz frequency band were highly localized, with effective source levels of 108.8 to 120.0 dB re 1 µPa @ 1 m and transmission loss approximating a cylindrical geometric spreading model. This soundscape characterization study suggests that spatial heterogeneity in ambient sound could serve as a reliable indicator of habitat type and potentially convey habitat quality information to dispersing organisms. KEY WORDS: Passive acoustics · Soundscape ecology · Habitat-associated sound · Acoustic diversity · Pamlico Sound · Subtidal oyster reef Full text in pdf format Information about this Feature Article NextCite this article as: Lillis A, Eggleston DB, Bohnenstiehl DR (2014) Estuarine soundscapes: distinct acoustic characteristics of oyster reefs compared to soft-bottom habitats. Mar Ecol Prog Ser 505:1-17. https://doi.org/10.3354/meps10805 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 505. Online publication date: May 28, 2014 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2014 Inter-Research. DA - 2014/// PY - 2014/// DO - 10.3354/meps10805 VL - 505 SP - 1-17 SN - 1616-1599 KW - Passive acoustics KW - Soundscape ecology KW - Habitat-associated sound KW - Acoustic diversity KW - Pamlico Sound KW - Subtidal oyster reef ER - TY - JOUR TI - Contribution of pollen to atmospheric ice nuclei concentrations AU - Hader, J. D. AU - Wright, T. P. AU - Petters, M. D. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 11 SP - 5433-5449 ER - TY - JOUR TI - Colored Dissolved Organic Matter Dynamics in the Northern Gulf of Mexico from Ocean Color and Numerical Model Results AU - Chaichitehrani, Nazanin AU - D'Sa, Eurico J. AU - Ko, Dong S. AU - Walker, Nan D. AU - Osburn, Christopher L. AU - Chen, Robert F. T2 - Journal of Coastal Research AB - Chaichitehrani, N.; D'Sa, E.J.; Ko, D.S.; Walker, N.D.; Osburn, C.L., and Chen, R.F., 2014. Colored dissolved organic matter dynamics in the Northern Gulf of Mexico from ocean color and numerical model results. Colored dissolved organic matter (CDOM) absorption and salinity relationships were assessed and used in conjunction with the salinity and current outputs of a numerical model (Navy Coastal Ocean Model [NCOM]) to study CDOM dynamics in the northern Gulf of Mexico. In situ CDOM absorption and salinity obtained from multiple field campaigns were inversely correlated seasonally (winter–spring and summer) and latitudinally (inner- and outer-shelf zones), suggesting conservative behavior of CDOM distribution. A weaker correlation, during summer in the outer-shelf zone, however, indicated stronger effects of photooxidation and lower masking effects from riverine CDOM. Applying these relationships to simulated salinity resulted in hourly maps of CDOM that revealed similarities to CDOM patterns derived from SeaWiFS satellite imagery. Further, matchup comparisons between model-derived and in situ CDOM absorption were statistically sound for the summer (bias = −0.016, root mean square error = 0.059, r2 = 0.51 SI = 0.28) and the winter–spring periods (bias = 0.033, root mean square error = 0.099, r2 = 0.52, SI = 0.21). Overlaying the model-derived CDOM maps on the simulated currents revealed the strong influence of currents on CDOM advection. Downcoast currents during the nonsummer months led to persistent advection of CDOM westward interrupted by frequent cold front events that flush CDOM-laden waters out of the coastal bays onto the inner and outer continental shelves. In contrast, the upcoast current regime, though less well organized, produces a more significant seaward advection of CDOM, likely due to the Ekman transport and subsequent entrainment by mesoscale eddies over the continental slope. DA - 2014/7// PY - 2014/7// DO - 10.2112/jcoastres-d-13-00036.1 VL - 296 IS - 4 SP - 800-814 J2 - Journal of Coastal Research LA - en OP - SN - 0749-0208 1551-5036 UR - http://dx.doi.org/10.2112/JCOASTRES-D-13-00036.1 DB - Crossref KW - CDOM KW - salinity KW - Sea WiFS KW - NCOM model ER - TY - JOUR TI - Coastal connectivity in the Gulf of Maine in spring and summer of 2004-2009 AU - Li, Yizhen AU - He, Ruoying AU - Manning, James P. T2 - DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY AB - Coastal ocean connectivity associated with the Gulf of Maine (GOM) surface flows in spring and summer seasons of 2004–2009 is studied using surface numerical particle tracking based on realistic regional ocean circulation hindcast solutions. Seven initial particle release sites are selected in key gulf regions often affected by harmful algal (Alexandrium fundyense) blooms, including Massachusetts Bay, the western GOM coastal area, the eastern GOM coastal area, the Bay of Fundy, Wilkinson Basin, the Jordan Basin, and a region seaward of Penobscot Bay. Surface particles are released every 5 days between February 1st and August 1st in each year, and the variability in their trajectories on interannual time scales is quantified by Lagrangian probability density function calculations. Coastal connectivity is further quantified using a connectivity matrix, identifying source and destination functions. Our results suggest that the interannual variability in coastal connectivity has strong impact on the spatial distribution of A. fundyense blooms in each year. DA - 2014/5// PY - 2014/5// DO - 10.1016/j.dsr2.2013.01.037 VL - 103 SP - 199-209 SN - 1879-0100 KW - Gulf of Maine KW - Coastal circulation KW - Connectivity KW - Lagrangian PDFs KW - Interannual variability KW - Source and destination strengths ER - TY - JOUR TI - Active simultaneous uplift and margin-normal extension in a forearc high, Crete, Greece AU - Gallen, S. F. AU - Wegmann, K. W. AU - Bohnenstiehl, D. R. AU - Pazzaglia, F. J. AU - Brandon, M. T. AU - Fassoulas, C. T2 - EARTH AND PLANETARY SCIENCE LETTERS AB - The island of Crete occupies a forearc high in the central Hellenic subduction zone and is characterized by sustained exhumation, surface uplift and extension. The processes governing orogenesis and topographic development here remain poorly understood. Dramatic topographic relief (2–6km) astride the southern coastline of Crete is associated with large margin-parallel faults responsible for deep bathymetric depressions known as the Hellenic troughs. These structures have been interpreted as both active and inactive with either contractional, strike-slip, or extensional movement histories. Distinguishing between these different structural styles and kinematic histories here allows us to explore more general models for improving our global understanding of the tectonic and geodynamic processes of syn-convergent extension. We present new observations from the south–central coastline of Crete that clarifies the role of these faults in the late Cenozoic evolution of the central Hellenic margin and the processes controlling Quaternary surface uplift. Pleistocene marine terraces are used in conjunction with optically stimulated luminesce dating and correlation to the Quaternary eustatic curve to document coastal uplift and identify active faults. Two south-dipping normal faults are observed, which extend offshore, offset these marine terrace deposits and indicate active N–S (margin-normal) extension. Further, marine terraces preserved in the footwall and hanging wall of both faults demonstrate that regional net uplift of Crete is occurring despite active extension. Field mapping and geometric reconstructions of an active onshore normal fault reveal that the subaqueous range-front fault of south–central Crete is synthetic to the south-dipping normal faults on shore. These findings are inconsistent with models of active horizontal shortening in the upper crust of the Hellenic forearc. Rather, they are consistent with topographic growth of the forearc in a viscous orogenic wedge, where crustal thickening and uplift are a result of basal underplating of material that is accompanied by extension in the upper portions of the wedge. Within this framework a new conceptual model is presented for the late Cenozoic vertical tectonics of the Hellenic forearc. DA - 2014/7/15/ PY - 2014/7/15/ DO - 10.1016/j.epsl.2014.04.038 VL - 398 SP - 11-24 SN - 1385-013X KW - tectonic geomorphology KW - marine terrace KW - normal fault KW - uplift KW - underplating ER - TY - JOUR TI - Using in situ ultraviolet-visual spectroscopy to measure nitrogen, carbon, phosphorus, and suspended solids concentrations at a high frequency in a brackish tidal marsh AU - Etheridge, J. Randall AU - Birgand, François AU - Osborne, Jason A. AU - Osburn, Christopher L. AU - Burchell, Michael R. AU - Irving, Justin T2 - Limnol. Oceanogr. Methods AB - The collection of high frequency water quality data are key to making the next leap in hydrological and biogeochemical sciences. Commercially available in situ ultraviolet‐visual (UV‐Vis) spectrometers make possible the long‐term collection of absorption spectra multiple times per hour. This technology has proven useful for measuring nitrate, dissolved organic carbon, and total suspended solids in many environments, but has not been tested in tidal marsh conditions where upstream freshwater mixes with estuarine waters, resulting in rapid changes in concentrations and salinity. These three parameters encompass only a portion of the nutrients that are of interest in these systems. To test the potential of spectroscopy to measure these and other nutrient concentrations, spectrometers were installed in a constructed brackish tidal marsh and absorbance spectra were compared to lab analyses for coinciding discrete samples. Variable selection techniques, including partial least squares regression, lasso regression, and stepwise regression, were used to develop models with which nitrate, total kjeldahl nitrogen, dissolved organic carbon, phosphate, total phosphorus, total suspended solids, and salinity in brackish marsh waters can be predicted from UV‐Vis spectrometer measurements. Significant relationships between the absorption spectra and the laboratory measured concentrations were observed for all of the parameters. Phosphate and total phosphorus were the only nutrients which had R2 values less than 0.86 for their best calibrations. This study shows the potential to collect multiple water quality parameters at a high frequency in brackish waters using in situ spectrometers and gives the tools to replicate this analysis in all environments. DA - 2014/1// PY - 2014/1// DO - 10.4319/lom.2014.12.10 VL - 12 IS - 1 SP - 10-22 ER - TY - JOUR TI - Spatial and temporal variability of SST and ocean color in the Gulf of Maine based on cloud-free SST and chlorophyll reconstructions in 2003-2012 AU - Li, Yizhen AU - He, Ruoying T2 - REMOTE SENSING OF ENVIRONMENT AB - The spatial and temporal variability of sea surface temperature (SST) and Chlorophyll-a (Chl-a) in the Gulf of Maine (GOM) is examined using daily, cloud-free Data INterpolating Empirical Orthogonal Function (DINEOF) reconstructions during 2003–2012. The utility of the DINEOF SST and Chl-a is demonstrated through direct comparisons with buoy- and ship-based observations. EOF analyses of cloud-free products are further used to quantify the SST and Chl-a variability on seasonal to inter-annual timescales. The first mode of SST is dominated by an annual cycle in response to net surface heat flux, with SST lagging surface flux by ~ 57 days. The second mode of SST underscores interactions between GOM, the Scotian Shelf, and the slope sea in response to the basin scale atmospheric forcing represented by the North Atlantic Oscillation. The third mode correlates well with the evolution of Scotian Shelf-slope frontal displacement. The first EOF mode of Chl-a is dominated by a winter–spring bloom and a fall bloom, with a spatial distribution modified by the tidal mixing that facilitates nutrient delivery from the deep ocean. The second EOF mode is likely associated with a winter bloom in the warm slope sea, where the low-frequency variations of second modes of SST and Chl-a are in phase, suggesting a possible coupling between physical and biological responses to atmospheric forcing. The third mode of the Chl-a is likely associated with freshening events associated with advection of the Scotian Shelf Water, which enhance stratifications in the eastern GOM. DA - 2014/3/25/ PY - 2014/3/25/ DO - 10.1016/j.rse.2014.01.019 VL - 144 SP - 98-108 SN - 1879-0704 KW - Gulf of Maine KW - Chlorophyll bloom KW - Sea surface temperature KW - North Atlantic Oscillation KW - EOF analysis ER - TY - JOUR TI - Regional precipitation variability in East Asia related to climate and environmental factors during 1979-2012 AU - Deng, Yinyin AU - Gao, Tao AU - Gao, Huiwang AU - Yao, Xiaohong AU - Xie, Lian T2 - SCIENTIFIC REPORTS AB - This paper studies the inter-annual precipitation variations in different regions of East Asia from oceans to interior areas in China during 1979 - 2012. The results computed by Empirical Orthogonal Functions (EOF) demonstrate that the annual precipitation changes are mainly related to the El Niño-Southern Oscillation, East Asian summer monsoon and aerosols. We also found that the increased Sea surface temperature (SST) could explain the precipitation changes over the Northwest Pacific in the dry season (Oct. - May) and the East China Sea and the South China Sea in the rainy season (Jun. - Sep.). The precipitation changes over the ocean unexplained by SST were likely due to the water vapor transport dominated by dynamic factors. With the increased SST, the moisture transported from oceans to interior land was likely redistributed and caused the complicated regional variability of precipitation. Moreover, the impacts of aerosols on cloud and precipitation varied with different pollution levels and different seasons. DA - 2014/7/17/ PY - 2014/7/17/ DO - 10.1038/srep05693 VL - 4 SP - SN - 2045-2322 ER - TY - JOUR TI - Real-time air quality forecasting over the southeastern United States using WRF/Chem-MADRID: Multiple-year assessment and sensitivity studies AU - Yahya, Khairunnisa AU - Zhang, Yang AU - Vukoyich, Jeffrey M. T2 - ATMOSPHERIC ENVIRONMENT AB - An air quality forecasting system is a tool for protecting public health by providing an early warning system against harmful air pollutants. In this work, the online-coupled Weather Research and Forecasting Model with Chemistry with the Model of Aerosol Dynamics, Reaction, Ionization and Dissolution (WRF/Chem-MADRID) is used to forecast ozone (O3) and fine particles (PM2.5) concentrations over the southeastern U.S. for three O3 seasons from May to September in 2009, 2010, and 2011 and three winters from December to February during 2009–2010, 2010–2011, and 2011–2012. The forecasted chemical concentrations and meteorological variables are evaluated with observations from networks data in terms of spatial distribution, temporal variation, and discrete and categorical performance statistics. The model performs well for O3 and satisfactorily for PM2.5 in terms of both discrete and categorical evaluations but larger biases exist in PM species. The model biases are due to uncertainties in meteorological predictions, emissions, boundary conditions, chemical reactions, as well as uncertainties/differences in the measurement data used for evaluation. Sensitivity simulations show that using MEGAN online biogenic emissions and satellite-derived wildfire emissions result in improved performance for PM2.5 despite a degraded performance for O3. A combination of both can reduce normalize mean bias of PM2.5 from −18.3% to −11.9%. This work identifies a need to improve the accuracy of emissions by using dynamic biogenic and fire emissions that are dependent on meteorological conditions, in addition to the needs for more accurate anthropogenic emissions for urban areas and more accurate meteorological forecasts. DA - 2014/8// PY - 2014/8// DO - 10.1016/j.atmosenv.2014.04.024 VL - 92 SP - 318-338 SN - 1873-2844 KW - Real-time air quality forecast KW - O-3 KW - PM2.5 KW - WRF/Chem-MADRID KW - Online coupled model KW - Discrete and categorical evaluation KW - Satellite-derived wildfire emissions KW - MEGAN2 ER - TY - JOUR TI - Large-eddy simulation of stable boundary layer turbulence and estimation of associated wind turbine loads AU - Park, J. AU - Basu, S. AU - Manuel, L. T2 - WIND ENERGY AB - ABSTRACT Stochastic simulation of turbulent inflow fields commonly used in wind turbine load computations is unable to account for contrasting states of atmospheric stability. Flow fields in the stable boundary layer, for instance, have characteristics such as enhanced wind speed and directional shear; these effects can influence loads on utility‐scale wind turbines. To investigate these influences, we use large‐eddy simulation (LES) to generate an extensive database of high‐resolution ( ∼ 10 m), four‐dimensional turbulent flow fields. Key atmospheric conditions (e.g., geostrophic wind) and surface conditions (e.g., aerodynamic roughness length) are systematically varied to generate a diverse range of physically realizable atmospheric stabilities. We show that turbine‐scale variables (e.g., hub height wind speed, standard deviation of the longitudinal wind speed, wind speed shear, wind directional shear and Richardson number) are strongly interrelated. Thus, we strongly advocate that these variables should not be prescribed as independent degrees of freedom in any synthetic turbulent inflow generator but rather that any turbulence generation procedure should be able to bring about realistic sets of such physically realizable sets of turbine‐scale flow variables. We demonstrate the utility of our LES‐generated database in estimation of loads on a 5‐MW wind turbine model. More importantly, we identify specific turbine‐scale flow variables that are responsible for large turbine loads—e.g., wind speed shear is found to have a greater influence on out‐of‐plane blade bending moments for the turbine studied compared with its influence on other loads such as the tower‐top yaw moment and the fore‐aft tower base moment. Overall, our study suggests that LES may be effectively used to model inflow fields, to study characteristics of flow fields under various atmospheric stability conditions and to assess turbine loads for conditions that are not typically examined in design standards. Copyright © 2013 John Wiley & Sons, Ltd. DA - 2014/3// PY - 2014/3// DO - 10.1002/we.1580 VL - 17 IS - 3 SP - 359-384 SN - 1099-1824 KW - atmospheric boundary layer KW - fatigue loading KW - inflow generation KW - stable stratification KW - turbulence modeling KW - wind turbine ER - TY - JOUR TI - Dispersal of the Zhujiang River (Pearl River) derived sediment in the Holocene AU - Ge, Qian AU - Liu, J. P. AU - Xue, Zuo AU - Chu, Fengyou T2 - Acta Oceanologica Sinica DA - 2014/1/4/ PY - 2014/1/4/ DO - 10.1007/S13131-014-0407-8 VL - 33 IS - 8 SP - 1-9 J2 - Acta Oceanol. Sin. LA - en OP - SN - 0253-505X 1869-1099 UR - http://dx.doi.org/10.1007/S13131-014-0407-8 DB - Crossref KW - South China Sea KW - Zhujiang River KW - mud KW - clinoform ER - TY - JOUR TI - An ENSO-forecast independent statistical model for the prediction of annual Atlantic tropical cyclone frequency in April AU - Xie, K. AU - Liu, B. T2 - Advances in Meteorology DA - 2014/// PY - 2014/// ER - TY - JOUR TI - A Lagrangian model for phototaxis-induced thin layer formation AU - Yamazaki, Hidekatsu AU - Locke, Chris AU - Umlauf, Lars AU - Burchard, Hans AU - Ishimaru, Takashi AU - Kamykowski, Daniel T2 - DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY AB - We have developed a Lagrangian model to investigate a potential mechanism based on phototaxis behavior of phytoplankton cells for the formation of thin layers. We assume that all cells follow a time-regulated diurnal vertical migration during which they experience photo-acclimation based on the Denman and Marra (1986) model. When a cell experiences stress due to strong light that exceeds a threshold level, the cell swims downward, away from the light. We applied the Lagrangian model to a one dimensional second order turbulence closure model that generates a realistic surface mixing condition for a given set of physical parameters, such as wind and optical water type. For the chosen swimming velocities and prescribed behavior, we found that, in coastal water type and Jerlov III type, thin layer formation takes place up to 5 m s−1 winds, while 10 m s−1 winds cause sufficiently strong mixing to prevent the formation of thin layer. We have also investigated the effects of changing the irradiance threshold for the onset of the photoinhibition, the initial density profile and random walk swimming. In conclusion, thin layer formation due to photoinhibition may be possible for a low value of photoinhibition threshold that may occur either due to upwelling or strong light exposure. DA - 2014/3// PY - 2014/3// DO - 10.1016/j.dsr2.2012.12.010 VL - 101 SP - 193-206 SN - 1879-0100 KW - Phytoplankton KW - Diurnal vertical migration KW - Mixed layer KW - Turbulence KW - Lagrangian model ER - TY - JOUR TI - Visualizations of coastal terrain time series AU - Tateosian, Laura AU - Mitasova, Helena AU - Thakur, Sidharth AU - Hardin, Eric AU - Russ, Emily AU - Blundell, Bruce T2 - INFORMATION VISUALIZATION AB - In coastal regions, water, wind, gravitation, vegetation, and human activity continuously alter landscape surfaces. Visualizations are important for understanding coastal landscape evolution and its driving processes. Visualizing change in highly dynamic coastal terrain poses a formidable challenge; the combination of natural and anthropogenic forces leads to cycles of retreat and recovery and complex morphology of landforms. In recent years, repeated high-resolution laser terrain scans have generated a time series of point cloud data that represent landscapes at snapshots in time, including the impacts of major storms. In this article, we build on existing approaches for visualizing spatial–temporal data to create a collection of perceptual visualizations to support coastal terrain evolution analysis. We extract terrain features and track their migration; we derive temporal summary maps and heat graphs that quantify the pattern of elevation change and sediment redistribution and use the space–time cube concept to create visualizations of terrain evolution. The space–time cube approach allows us to represent shoreline evolution as an isosurface extracted from a voxel model created by stacking time series of digital elevation models. We illustrate our approach on a series of Light Detection and Ranging surveys of sandy North Carolina barrier islands. Our results reveal terrain changes of shoreline and dune ridge migration, dune breaches and overwash, the formation of new dune ridges, and the construction and destruction of homes, changes which are due to erosion and accretion, hurricanes, and human activities. These events are all visualized within their geographic and temporal contexts. DA - 2014/7// PY - 2014/7// DO - 10.1177/1473871613487086 VL - 13 IS - 3 SP - 266-282 SN - 1473-8724 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84906534191&partnerID=MN8TOARS KW - Visualization of time series KW - temporal visualization KW - geovisualization KW - visual perception KW - visual exploration KW - visualize changes KW - geospatial data KW - three-dimensional visualization KW - spatial data KW - visual exploration KW - space-time cube KW - geographic information systems KW - LiDAR KW - time series KW - terrain elevation KW - land surfaces KW - GIS GRASS ER - TY - JOUR TI - Variable Selection in Nonparametric Classification Via Measurement Error Model Selection Likelihoods AU - Stefanski, L. A. AU - Wu, Yichao AU - White, Kyle T2 - JOURNAL OF THE AMERICAN STATISTICAL ASSOCIATION AB - Using the relationships among ridge regression, LASSO estimation, and measurement error attenuation as motivation, a new measurement-error-model-based approach to variable selection is developed. After describing the approach in the familiar context of linear regression, we apply it to the problem of variable selection in nonparametric classification, resulting in a new kernel-based classifier with LASSO-like shrinkage and variable-selection properties. Finite-sample performance of the new classification method is studied via simulation and real data examples, and consistency of the method is studied theoretically. Supplementary materials for the paper are available online. DA - 2014/6// PY - 2014/6// DO - 10.1080/01621459.2013.858630 VL - 109 IS - 506 SP - 574-589 SN - 1537-274X KW - Attenuation KW - Bayes rule KW - Binary regression KW - Convolution KW - Discriminant analysis KW - Kernel discriminant analysis KW - LASSO KW - Linear regression KW - Maximum likelihood rule KW - Model selection KW - Ridge regression ER - TY - JOUR TI - The 2013 severe haze over southern Hebei, China: model evaluation, source apportionment, and policy implications AU - Wang, L. T. AU - Wei, Z. AU - Yang, J. AU - Zhang, Y. AU - Zhang, F. F. AU - Su, J. AU - Meng, C. C. AU - Zhang, Q. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 6 SP - 3151-3173 ER - TY - JOUR TI - Runoff-mediated seasonal oscillation in the dynamics of dissolved organic matter in different branches of a large bifurcated estuary-The Changjiang Estuary AU - Guo, Weidong AU - Yang, Liyang AU - Zhai, Weidong AU - Chen, Wenzhao AU - Osburn, Christopher L. AU - Huang, Xiao AU - Li, Yan T2 - Journal of Geophysical Research: Biogeosciences AB - Abstract The Changjiang Estuary is a large bifurcated estuary where different hydrodynamic processes influence its South Branch compared to its North Branch. The South Branch is the dominant pathway of Changjiang River discharge, while the shallower and narrower North Branch is dominated by salt water intrusion, especially in the dry season. Absorption and fluorescence spectroscopy were measured along with dissolved organic carbon (DOC) concentrations to characterize the properties of dissolved organic matter (DOM) collected in different seasons during an extreme drought year in 2011. The refractory DOM from the Changjiang River flowed mainly through the South Branch, whereas in the lower South Branch, the input from the polluted Huangpu River contributed a large amount of biolabile DOM, demonstrating an anthropogenic perturbation from megacities. The DOM properties in the North Branch showed conservative behavior in the wet season, while noticeable addition was observed in the dry season, accompanied by the reversed flux of DOM from the North Branch to the South Branch, emphasizing the regular seasonal oscillation of the DOM dynamics in this monsoon‐controlled bifurcated estuary. The estuarine turbidity maximum zones played distinct roles on DOM dynamics in different estuarine environments. The DOC and chromophoric DOM (CDOM) abundance in the Changjiang River and other Chinese rivers were at lower levels compared to other world rivers, showing a characteristic of the regional CDOM‐poor features for many East Asia rivers. DA - 2014/5// PY - 2014/5// DO - 10.1002/2013jg002540 VL - 119 IS - 5 SP - 776-793 J2 - J. Geophys. Res. Biogeosci. LA - en OP - SN - 2169-8953 UR - http://dx.doi.org/10.1002/2013JG002540 DB - Crossref KW - Changjiang Estuary KW - dissolved organic matter KW - fluorescence KW - bifurcated estuary KW - estuarine turbidity maximum KW - flux ER - TY - JOUR TI - Potential impacts of climate change on soil erosion vulnerability across the conterminous United States AU - Segura, C. AU - Sun, G. AU - McNulty, S. AU - Zhang, Y. T2 - Journal of Soil & Water Conservation DA - 2014/// PY - 2014/// VL - 69 IS - 2 SP - 171-181 ER - TY - JOUR TI - On the attribution of the changing hydrological cycle in Poyang Lake Basin, China AU - Sun, S. L. AU - Chen, H. S. AU - Ju, W. M. AU - Yu, M. AU - Hua, W. J. AU - Yin, Y. T2 - Journal of Hydrology DA - 2014/// PY - 2014/// VL - 514 SP - 214-225 ER - TY - JOUR TI - Monthly to interannual variability of microbial eukaryote assemblages at four depths in the eastern North Pacific AU - Kim, Diane Y. AU - Countway, Peter D. AU - Jones, Adriane C. AU - Schnetzer, Astrid AU - Yamashita, Warren AU - Tung, Christine AU - Caron, David A. T2 - ISME JOURNAL AB - The monthly, seasonal and interannual variability of microbial eukaryote assemblages were examined at 5 m, the deep chlorophyll maximum, 150 m and 500 m at the San Pedro Ocean Time-series station (eastern North Pacific). The depths spanned transitions in temperature, light, nutrients and oxygen, and included a persistently hypoxic environment at 500 m. Terminal restriction fragment length polymorphism was used for the analysis of 237 samples that were collected between September 2000 and December 2010. Spatiotemporal variability patterns of microeukaryote assemblages indicated the presence of distinct shallow and deep communities at the SPOT station, presumably reflecting taxa that were specifically adapted for the conditions in those environments. Community similarity values between assemblages collected 1 month apart at each depth ranged between ∼20% and ∼84% (averages were ∼50-59%). The assemblage at 5 m was temporally more dynamic than deeper assemblages and also displayed substantial interannual variability during the first ∼3 years of the study. Evidence of seasonality was detected for the microbial eukaryote assemblage at 5 m between January 2008 and December 2010 and at 150 m between September 2000 and December 2003. Seasonality was not detected for assemblages at the deep chlorophyll a maximum, which varied in depth seasonally, or at 500 m. Microbial eukaryote assemblages exhibited cyclical patterns in at least 1 year at each depth, implying an annual resetting of communities. Substantial interannual variability was detected for assemblages at all depths and represented the largest source of temporal variability in this temperate coastal ecosystem. DA - 2014/3// PY - 2014/3// DO - 10.1038/ismej.2013.173 VL - 8 IS - 3 SP - 515-530 SN - 1751-7370 KW - 18S rRNA gene KW - microbial eukaryotes KW - protists KW - temporal variability KW - time series ER - TY - JOUR TI - Larval dispersal and population connectivity among a network of marine reserves AU - Puckett, Brandon J. AU - Eggleston, David B. AU - Kerr, Patrick C. AU - Luettich, Richard A., Jr. T2 - FISHERIES OCEANOGRAPHY AB - Abstract A major challenge in marine ecology is describing patterns of larval dispersal and population connectivity, as well as their underlying processes. We used a biophysical model to simulate dispersal of eastern oyster, Crassostrea virginica , larvae and connectivity among a network of 10 no‐take reserves in a shallow, wind‐driven estuary to assess the relative importance of spawning location, spawning date, larval behavior, larval mortality, and adult reproductive output to predicted dispersal and connectivity patterns. The location (i.e., natal reserve) and date of spawning relative to physical processes, particularly frequency of wind reversals, were the dominant drivers of dispersal and connectivity patterns. To a lesser extent, larval behavior (i.e., 3D vertical advection and ontogenetic depth regulation) and mortality modified dispersal and connectivity, whereas spatiotemporal variability in adult reproductive output was of minimal importance. Over a 21‐day larval duration, mean dispersal distance of passive surface particles ranged from 5 to 40 km. Reserves were too small (1 km 2 ) relative to mean dispersal distances to promote extensive local retention (median 2%) and spaced too far apart (typically ~50 km) to promote extensive inter‐reserve connectivity (median 2%). Limited connectivity and local retention may preclude the network from being self‐sustainable, thereby limiting its long‐term conservation and management benefits. In reserve systems characterized by limited connectivity, management efforts should focus on increasing connectivity by increasing the number or size of reserves to realize the benefits of improved adult demographics within reserves. DA - 2014/7// PY - 2014/7// DO - 10.1111/fog.12067 VL - 23 IS - 4 SP - 342-361 SN - 1365-2419 KW - biophysical model KW - connectivity KW - Crassostrea virginica KW - demographics KW - larval dispersal KW - marine reserves KW - Pamlico Sound ER - TY - JOUR TI - Diabasic intrusion and lavas, segregation veins, and magma differentiation at Kahoolawe volcano, Hawaii AU - Fodor, R. V. AU - Bauer, G. R. T2 - Mineralogy and Petrology DA - 2014/// PY - 2014/// DO - 10.1007/s00710-013-0299-x VL - 108 IS - 2 SP - 269-286 ER - TY - JOUR TI - Use of a watershed hydrologic model to estimate interbasin groundwater flow in a Costa Rican rainforest AU - Zanon, Carlo AU - Genereux, David P. AU - Oberbauer, Steven F. T2 - HYDROLOGICAL PROCESSES AB - Abstract The watershed hydrologic model TOPMODEL was used to estimate interbasin groundwater flow (IGF) into a small lowland rainforest watershed in Costa Rica. IGF is a common hydrological process but often difficult to quantify. Four‐year simulations (2006–2009) using three different model approaches gave estimates of IGF that were very similar to each other (10.1, 10.2, and 9.8 m/year) and to an earlier estimate (10.0 m/year) based on 1998–2002 data from a budget study that did not use a hydrologic simulation model, providing confidence in the new estimates and suggesting each of the three model approaches is viable. Results show no significant temporal variation in IGF during 2006–2009 (or between this period and the earlier study from 1998–2002). Simulations of the 16 consecutive 3‐month periods in 2006–2009 gave 16 values of IGF rate with a mean (10.1 m/year, standard deviation = 0.6 m/year) very similar to the estimates above from the 4‐year simulations. This suggests the modified version of TOPMODEL can be used to model stream discharge and estimate IGF for sub‐annual time periods during which change in water storage is not necessarily equal to zero. Thus, simple watershed models may be used to estimate IGF based on even relatively short calibration periods, making such models useful tools in the study of this widespread hydrological process that affects water and chemical fluxes and budgets but is often difficult and costly to quantify. Copyright © 2013 John Wiley & Sons, Ltd. DA - 2014/5/15/ PY - 2014/5/15/ DO - 10.1002/hyp.9917 VL - 28 IS - 10 SP - 3670-3680 SN - 1099-1085 KW - groundwater KW - interbasin groundwater flow KW - watershed KW - rainforest KW - hydrologic model ER - TY - JOUR TI - Improving mass-wasting inventories by incorporating debris flow topographic signatures AU - Lyons, N.J. AU - Mitasova, Helena AU - Wegmann, K.W. T2 - Landslides DA - 2014/// PY - 2014/// DO - 10.1007/s10346-013-0398-0 VL - 11 IS - 3 SP - 385-397 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84902003440&partnerID=MN8TOARS ER - TY - JOUR TI - INTEGRATED METEOROLOGY AND CHEMISTRY MODELING Evaluation and Research Needs AU - Pleim, Jonathan AU - Mathur, Rohit AU - Rao, S. T. AU - Fast, Jerome AU - Baklanov, Alexander T2 - BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY AB - CORRESPONDING AUTHOR: Jonathan Pleim, U.S. Environmental Protection Agency, E243-03, Research Triangle Park, NC 27711, E-mail: pleim.jon@epa.gov DA - 2014/4// PY - 2014/4// DO - 10.1175/bams-d-13-00107.1 VL - 95 IS - 4 SP - ES81-ES84 SN - 1520-0477 ER - TY - JOUR TI - Untitled AU - Rao, S. Trivikrama T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION DA - 2014/1/2/ PY - 2014/1/2/ DO - 10.1080/10962247.2014.868213 VL - 64 IS - 1 SP - 1-1 SN - 2162-2906 ER - TY - JOUR TI - Sedimentary processes on the Mekong subaqueous delta: Clay mineral and geochemical analysis AU - Xue, Zuo AU - Liu, J. Paul AU - DeMaster, Dave AU - Leithold, Elana L. AU - Wan, Shiming AU - Ge, Qian AU - Nguyen, Van Lap AU - Ta, Thi Kim Oanh T2 - Journal of Asian Earth Sciences AB - Sedimentary processes on the inner Mekong Shelf were investigated by examining the characteristics of sediments sampled in gravity cores at 15 locations, including grain size, clay mineralogy, sediment accumulation rates, and the elemental and stable carbon isotopic composition of organic matter (atomic C/N ratios and δ13C). Deltaic deposits exhibit contrasting characteristics along different sides of the delta plain (South China Sea, SCS hereafter, to the east and Gulf of Thailand, GOT hereafter, to the west) as well as on and off the subaqueous deltaic system. On one hand, cores recovered from the subaqueous delta in the SCS/GOT are consisted of poorly/well sorted sediments with similar/different clay mineral assemblage with/from Mekong sediments. Excess 210Pb profiles, supported by 14C chronologies, indicate either “non-steady” (SCS side) or “rapid accumulation” (GOT side) processes on the subaqueous delta. The δ13C and C/N ratio indicate a mixture of terrestrial and marine-sourced organic matter in the deltaic sediment. On the other hand, cores recovered from areas with no deltaic deposits or seaward of the subaqueous delta show excess 210Pb profiles indicating “steady-state” accumulation with a greater proportion of marine-sourced organic matter. Core analysis’s relevance with local depositional environment and previous acoustic profiling are discussed. DA - 2014/1// PY - 2014/1// DO - 10.1016/j.jseaes.2012.07.012 VL - 79 SP - 520–528 SN - 1367-9120 UR - http://dx.doi.org/10.1016/j.jseaes.2012.07.012 KW - South China Sea KW - Mekong River Delta KW - Clay mineralogy KW - Organic carbon KW - Depositional environment ER - TY - JOUR TI - Multivariate Regression Analysis and Statistical Modeling for Summer Extreme Precipitation over the Yangtze River Basin, China AU - Gao, Tao AU - Xie, Lian T2 - ADVANCES IN METEOROLOGY AB - Extreme precipitation is likely to be one of the most severe meteorological disasters in China; however, studies on the physical factors affecting precipitation extremes and corresponding prediction models are not accurately available. From a new point of view, the sensible heat flux (SHF) and latent heat flux (LHF), which have significant impacts on summer extreme rainfall in Yangtze River basin (YRB), have been quantified and then selections of the impact factors are conducted. Firstly, a regional extreme precipitation index was applied to determine Regions of Significant Correlation (RSC) by analyzing spatial distribution of correlation coefficients between this index and SHF, LHF, and sea surface temperature (SST) on global ocean scale; then the time series of SHF, LHF, and SST in RSCs during 1967–2010 were selected. Furthermore, other factors that significantly affect variations in precipitation extremes over YRB were also selected. The methods of multiple stepwise regression and leave-one-out cross-validation (LOOCV) were utilized to analyze and test influencing factors and statistical prediction model. The correlation coefficient between observed regional extreme index and model simulation result is 0.85, with significant level at 99%. This suggested that the forecast skill was acceptable although many aspects of the prediction model should be improved. DA - 2014/// PY - 2014/// DO - 10.1155/2014/269059 VL - 2014 SP - SN - 1687-9317 ER - TY - JOUR TI - Water spray geoengineering to clean air pollution for mitigating haze in China's cities AU - Yu, Shaocai T2 - ENVIRONMENTAL CHEMISTRY LETTERS DA - 2014/3// PY - 2014/3// DO - 10.1007/s10311-013-0444-0 VL - 12 IS - 1 SP - 109-116 SN - 1610-3661 KW - Air pollution KW - Haze KW - Precipitation scavenging KW - Geoengineering approach KW - Megacities ER - TY - JOUR TI - Response of Estuarine Fish to Large-Scale Oyster Reef Restoration AU - Pierson, Katherine J. AU - Eggleston, David B. T2 - TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY AB - Abstract Restoration of oyster reefs is increasing worldwide due to oyster populations reaching historic lows and recognition of the many ecosystem services provided by oyster reefs, such as essential fish habitat. This study took advantage of an existing network of subtidal oyster reefs and a large‐scale oyster reef restoration effort in Pamlico Sound, North Carolina, to (1) compare estuarine fish assemblages on oyster reefs with those on unstructured bottom, (2) identify the short‐term change in fish abundance and richness in response to reef creation, and (3) identify spatiotemporal trends in fish abundance and richness. We quantified transient and reef fish using gill nets and fish traps, respectively. Oyster reefs harbored more unique species than unstructured bottom, thereby enhancing the overall diversity of estuarine fish assemblages. Fish abundance on recently created experimental reefs (6–8 months postconstruction) was similar to that on control reefs that were 4–6 years old, suggesting rapid colonization of new reefs. Fish diversity at 1 of 2 sites actually decreased on control reefs after reef construction, suggesting that rapid colonization of new reefs was due, in part, to the movement of fish from old to new reefs. Information on the distribution, abundance, and diversity of estuarine fish in relation to restored oyster reefs will improve our understanding of oyster reefs as essential fish habitat. DA - 2014/1/1/ PY - 2014/1/1/ DO - 10.1080/00028487.2013.847863 VL - 143 IS - 1 SP - 273-288 SN - 1548-8659 ER - TY - JOUR TI - Melanosomes or Microbes: Testing an Alternative Hypothesis for the Origin of Microbodies in Fossil Feathers AU - Moyer, A. E. AU - Zheng, W. X. AU - Johnson, E. A. AU - Lamanna, M. C. AU - Li, D. Q. AU - Lacovara, K. J. AU - Schweitzer, M. H. T2 - Scientific Reports DA - 2014/// PY - 2014/// VL - 4 ER - TY - JOUR TI - Composite VORTEX2 Supercell Environments from Near-Storm Soundings AU - Parker, Matthew D. T2 - MONTHLY WEATHER REVIEW AB - Abstract Three-dimensional composite analyses using 134 soundings from the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) reveal the nature of near-storm variability in the environments of supercell thunderstorms. Based upon the full analysis, it appears that vertical wind shear increases as one approaches a supercell within the inflow sector, providing favorable conditions for supercell maintenance (and possibly tornado formation) despite small amounts of low-level cooling near the storm. The seven analyzed tornadic supercells have a composite environment that is clearly more impressive (in terms of widely used metrics) than that of the five analyzed nontornadic supercells, including more convective available potential energy (CAPE), more vertical wind shear, higher boundary layer relative humidity, and lower tropospheric horizontal vorticity that is more streamwise in the near-storm inflow. The widely used supercell composite parameter (SCP) and significant tornado parameter (STP) summarize these differences well. Comparison of composite environments from early versus late in supercells' lifetimes reveals only subtle signs of storm-induced environmental modification, but potentially important changes associated with the evening transition toward a cooler and moister boundary layer with enhanced low-level vertical shear. Finally, although this study focused primarily on the composite inflow environment, it is intriguing that the outflows sampled by VORTEX2 soundings were surprisingly shallow (generally ≤500 m deep) and retained considerable CAPE (generally ≥1000 J kg−1). The numerous VORTEX2 near-storm soundings provide an unprecedented observational view of supercell–environment interactions, and the analyses are ripe for use in a variety of future studies. DA - 2014/2// PY - 2014/2// DO - 10.1175/mwr-d-13-00167.1 VL - 142 IS - 2 SP - 508-529 SN - 1520-0493 KW - Convective storms KW - Convective-scale processes KW - Soundings KW - Mesoscale forecasting ER - TY - JOUR TI - Acoustic response of submarine volcanoes in the Tofua Arc and northern Lau Basin to two great earthquakes AU - Bohnenstiehl, DelWayne R. AU - Dziak, Robert P. AU - Matsumoto, Haru AU - Conder, James A. T2 - GEOPHYSICAL JOURNAL INTERNATIONAL AB - Using a short-baseline hydrophone array, persistent volcanoacoustic sources are identified within the ambient noise field of the Lau Basin during the period between 2009 January and 2010 April. The submarine volcano West Mata and adjacent volcanic terrains, including the northern Matas and Volcano O, are the most active acoustic sources during the 15-month period of observation. Other areas of long-term activity include the Niua hydrothermal field, the volcanic islands of Hunga Ha'apai, Founalei, Niuatoputapu and Niuafo'ou, two seamounts located along the southern Tofua Arc and at least three unknown sites within the northern Lau Basin. Following the great Samoan earthquake on 2009 September 29, seven of the volcanoacoustic sources identified exhibit increases in the rate of acoustic detection. These changes persist over timescales of days-to-months and are observed up to 900 km from the earthquake hypocentre. At least one of the volcanoacoustic sources that did not respond to the 2009 Samoan earthquake exhibits an increase in detection rate following the great Mw 8.8 Chile earthquake that occurred at a distance of ∼9500 km on 2010 February 27. These observations suggest that great earthquakes may have undocumented impacts on Earth's vast submarine volcanic systems, potentially increasing the short-term flux of magma and volcanic gas into the overlying ocean. DA - 2014/3// PY - 2014/3// DO - 10.1093/gji/ggt472 VL - 196 IS - 3 SP - 1657-1675 SN - 1365-246X KW - Volcano seismology KW - Volcanic arc processes KW - Backarc basin processes KW - Subaqueous volcanism ER - TY - JOUR TI - Submicrometre particle filtration with a dc activated plasma textile AU - Rasipuram, S. C. AU - Wu, M. AU - Kuznetsov, I. A. AU - Kuznetsov, A. V. AU - Levine, J. F. AU - Jasper, W. J. AU - Saveliev, A. V. T2 - JOURNAL OF PHYSICS D-APPLIED PHYSICS AB - Plasma textiles are novel fabrics incorporating the advantages of cold plasma and low-cost non-woven or woven textile fabrics. In plasma textiles, electrodes are integrated into the fabric, and a corona discharge is activated within and on the surface of the fabric by applying high voltages above 10 kV between the electrodes. When the plasma textile is activated, submicrometre particles approaching the textile are charged by the deposition of ions and electrons produced by the corona, and then collected by the textile material. A stable plasma discharge was experimentally verified on the surface of the textile that was locally smooth but not rigid. A filtration efficiency close to 100% was observed in experiments conducted on salt particles with diameters ranging from 50 to 300 nm. Unlike conventional fibrous filters, the plasma textile provided uniform filtration in this range, without exhibiting a maximum particle penetration size. DA - 2014/1/15/ PY - 2014/1/15/ DO - 10.1088/0022-3727/47/2/025201 VL - 47 IS - 2 SP - SN - 1361-6463 KW - non-thermal plasmas KW - filtration KW - corona discharge KW - plasma textile ER - TY - JOUR TI - Online coupled regional meteorology chemistry models in Europe: Current status and prospects AU - Baklanov, A. AU - Schlunzen, K. AU - Suppan, P. AU - Baldasano, J. AU - Brunner, D. AU - Aksoyoglu, S. AU - Carmichael, G. AU - Douros, J. AU - Flemming, J. AU - Forkel, R. AU - Galmarini, S. AU - Gauss, M. AU - Grell, G. AU - Hirtl, M. AU - Joffre, S. AU - Jorba, O. AU - Kaas, E. AU - Kaasik, M. AU - Kallos, G. T2 - Atmospheric Chemistry and Physics DA - 2014/// PY - 2014/// VL - 14 IS - 1 SP - 317-398 ER - TY - JOUR TI - Observational Support for the Stability Dependence of the Bulk Richardson Number Across the Stable Boundary Layer AU - Basu, S. AU - Holtslag, A. A. M. AU - Caporaso, L. AU - Riccio, A. AU - Steeneveld, G-J T2 - BOUNDARY-LAYER METEOROLOGY DA - 2014/3// PY - 2014/3// DO - 10.1007/s10546-013-9878-y VL - 150 IS - 3 SP - 515-523 SN - 1573-1472 KW - Boundary-layer height KW - Stable boundary layer KW - Turbulence ER - TY - JOUR TI - Measurement and Modeling of Hydrogen Sulfide Lagoon Emissions from a Swine Concentrated Animal Feeding Operation AU - Rumsey, Ian C. AU - Aneja, Viney P. T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Hydrogen sulfide (H2S) emissions were determined from an anaerobic lagoon at a swine concentrated animal feeding operation (CAFO) in North Carolina. Measurements of H2S were made continuously from an anaerobic lagoon using a dynamic flow-through chamber for ∼ 1 week during each of the four seasonal periods from June 2007 through April 2008. H2S lagoon fluxes were highest in the summer with a flux of 3.81 ± 3.24 μg m(-2) min(-1) and lowest in the winter with a flux of 0.08 ± 0.09 μg m(-2) min(-1). An air-manure interface (A-MI) mass transfer model was developed to predict H2S manure emissions. The accuracy of the A-MI mass transfer model in predicting H2S manure emissions was comprehensively evaluated by comparing the model predicted emissions to the continuously measured lagoon emissions using data from all four seasonal periods. In comparison to this measurement data, the A-MI mass transfer model performed well in predicting H2S fluxes with a slope of 1.13 and an r(2) value of 0.60, and a mean bias value of 0.655 μg m(-2) min(-1). The A-MI mass transfer model also performed fairly well in predicting diurnal H2S lagoon flux trends. DA - 2014/2/4/ PY - 2014/2/4/ DO - 10.1021/es403716w VL - 48 IS - 3 SP - 1609-1617 SN - 1520-5851 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84893569333&partnerID=MN8TOARS ER -