TY - JOUR TI - Detecting vulnerability of humid tropical forests to multiple stressors AU - Saatchi, Sassan AU - Longo, Marcos AU - Xu, Liang AU - Yang, Yan AU - Abe, Hitofumi AU - André, Michel AU - Aukema, Juliann E. AU - Carvalhais, Nuno AU - Cadillo-Quiroz, Hinsby AU - Cerbu, Gillian Ann AU - Chernela, Janet M. AU - Covey, Kristofer AU - Sánchez-Clavijo, Lina María AU - Cubillos, Isai V. AU - Davies, Stuart J. AU - Sy, Veronique De AU - Vleeschouwer, Francois De AU - Duque, Alvaro AU - Durieux, Alice Marie Sybille AU - Fernandes, Kátia De Avila AU - Fernandez, Luis E. AU - Gammino, Victoria AU - Garrity, Dennis P. AU - Gibbs, David A. AU - Gibbon, Lucy AU - Gowae, Gae Yansom AU - Hansen, Matthew AU - Harris, Nancy Lee AU - Healey, Sean P. AU - Hilton, Robert G. AU - Johnson, Christine May AU - Kankeu, Richard Sufo AU - Laporte-Goetz, Nadine Therese AU - Lee, Hyongki AU - Lovejoy, Thomas AU - Lowman, Margaret AU - Lumbuenamo, Raymond AU - Malhi, Yadvinder AU - Martinez, Jean-Michel M. Albert AU - Nobre, Carlos AU - Pellegrini, Adam AU - Radachowsky, Jeremy AU - Román, Francisco AU - Russell, Diane AU - Sheil, Douglas AU - Smith, Thomas B. AU - Spencer, Robert G.M. AU - Stolle, Fred AU - Tata, Hesti Lestari AU - Castillo Torres, Dennis AU - Tshimanga, Raphael Muamba AU - Vargas, Rodrigo AU - Venter, Michelle AU - West, Joshua AU - Widayati, Atiek AU - Wilson, Sylvia N. AU - Brumby, Steven AU - Elmore, Aurora C. T2 - One Earth AB - Humid tropical forests play a dominant role in the functioning of Earth but are under increasing threat from changes in land use and climate. How forest vulnerability varies across space and time and what level of stress forests can tolerate before facing a tipping point are poorly understood. Here, we develop a tropical forest vulnerability index (TFVI) to detect and evaluate the vulnerability of global tropical forests to threats across space and time. We show that climate change together with land-use change have slowed the recovery rate of forest carbon cycling. Temporal autocorrelation, as an indicator of this slow recovery, increases substantially for above-ground biomass, gross primary production, and evapotranspiration when climate stress reaches a critical level. Forests in the Americas exhibit extensive vulnerability to these stressors, while in Africa, forests show relative resilience to climate, and in Asia reveal more vulnerability to land use and fragmentation. TFVI can systematically track the response of tropical forests to multiple stressors and provide early-warning signals for regions undergoing critical transitions. DA - 2021/7// PY - 2021/7// DO - 10.1016/j.oneear.2021.06.002 VL - 4 IS - 7 SP - 988–1003 ER - TY - JOUR TI - Demystifying Drought: Strategies to Enhance the Communication of a Complex Hazard AU - Ward, Rebecca AU - Lackstrom, Kirsten AU - Davis, Corey T2 - Bulletin of the American Meteorological Society AB - Abstract Drought is a complex phenomenon that is difficult to characterize and monitor. Accurate and timely communication is necessary to ensure that affected sectors and the public can respond and manage associated risks and impacts. To that end, myriad drought indicators, indices, and other tools have been developed and made available, but understanding and using this information can be a challenge for end users who are unfamiliar with the information or presentation or for decision-makers with expertise in areas outside of climate and drought. This article highlights a project that aimed to improve the usability and dissemination of drought information for North Carolina (NC) audiences by addressing specific needs for a better understanding of how drought is monitored, the climatic and environmental conditions that can cause or worsen drought, and the impacts occurring in NC’s different sectors and subregions. Conducted to support NC’s official, statewide drought monitoring process, the project’s methods and results have utility for other geographies and contexts. The project team designed an iterative process to engage users in the development, evaluation, refinement, and distribution of new resources. Featured products include the Weekly Drought Update infographic, which explains the factors used to determine NC’s drought status, and the Short-Range Outlook infographic, a synthesis of National Weather Service forecasts. Effective strategies included using stakeholders’ preferred and existing channels to disseminate products, emphasizing impacts relevant to different user groups (such as agriculture, forestry, and water resources) rather than indices, and employing concise narratives and visualizations to translate technical and scientific information. DA - 2021/8/27/ PY - 2021/8/27/ DO - 10.1175/bams-d-21-0089.1 VL - 8 SP - 1-43 UR - http://dx.doi.org/10.1175/bams-d-21-0089.1 KW - Social Science KW - Drought KW - Climate services KW - Communications/decision making ER - TY - JOUR TI - Regional temperature-ozone relationships across the US under multiple climate and emissions scenarios AU - Nolte, Christopher G. AU - Spero, Tanya L. AU - Bowden, Jared H. AU - Sarofim, Marcus C. AU - Martinich, Jeremy AU - Mallard, Megan S. T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION AB - The potential effects of 21st century climate change on ozone (O3) concentrations in the United States are investigated using global climate simulations to drive higher-resolution regional meteorological and chemical transport models. Community Earth System Model (CESM) and Coupled Model version 3 (CM3) simulations of the Representative Concentration Pathway 8.5 scenario are dynamically downscaled using the Weather Research and Forecasting model, and the resulting meteorological fields are used to drive the Community Multiscale Air Quality model. Air quality is modeled for five 11-year periods using both a 2011 air pollutant emission inventory and a future projection accounting for full implementation of promulgated regulatory controls. Across the U.S., CESM projects daily maximum temperatures during summer to increase 1–4°C by 2050 and 2–7°C by 2095, while CM3 projects warming of 2–7°C by 2050 and 4–11°C by 2095. The meteorological changes have geographically varying impacts on O3 concentrations. Using the 2011 emissions dataset, O3 increases 1–5 ppb in the central Great Plains and Midwest by 2050 and more than 10 ppb by 2095, but it remains unchanged or even decreases in the Gulf Coast, Maine, and parts of the Southwest. Using the projected emissions, modeled increases are attenuated while decreases are amplified, indicating that planned air pollution control measures ameliorate the ozone climate penalty. The relationships between changes in maximum temperature and changes in O3 concentrations are examined spatially and quantified to explore the potential for developing an efficient approach for estimating air quality impacts of other future climate scenarios.Implications: The effects of climate change on ozone air quality in the United States are investigated using two global climate model simulations of a high warming scenario for five decadal periods in the 21st century. Warming summer temperatures simulated under both models lead to higher ozone concentrations in some regions, with the magnitude of the change increasing with temperature over the century. The magnitude and spatial extent of the increases are attenuated under a future emissions projection that accounts for regulatory controls. Regional linear regression relationships are developed as a first step toward development of a reduced form model for efficient estimation of the health impacts attributable to changes in air quality resulting from a climate change scenario. DA - 2021/10/3/ PY - 2021/10/3/ DO - 10.1080/10962247.2021.1970048 VL - 71 IS - 10 SP - 1251-1264 SN - 2162-2906 ER - TY - JOUR TI - Limitations of WRF land surface models for simulating land use and land cover change in Sub-Saharan Africa and development of an improved model (CLM-AF v. 1.0) AU - Glotfelty, Timothy AU - Ramirez-Mejia, Diana AU - Bowden, Jared AU - Ghilardi, Adrian AU - West, J. Jason T2 - GEOSCIENTIFIC MODEL DEVELOPMENT AB - Abstract. Land use and land cover change (LULCC) impacts local and regional climates through various biogeophysical processes. Accurate representation of land surface parameters in land surface models (LSMs) is essential to accurately predict these LULCC-induced climate signals. In this work, we test the applicability of the default Noah, Noah-MP, and Community Land Model (CLM) LSMs in the Weather Research and Forecasting (WRF) model over Sub-Saharan Africa. We find that the default WRF LSMs do not accurately represent surface albedo, leaf area index, and surface roughness in this region due to various flawed assumptions, including the treatment of the MODIS woody savanna land use and land cover (LULC) category as closed shrubland. Consequently, we developed a WRF CLM version with more accurate African land surface parameters (CLM-AF), designed such that it can be used to evaluate the influence of LULCC. We evaluate meteorological performance for the default LSMs and CLM-AF against observational datasets, gridded products, and satellite estimates. Further, we conduct LULCC experiments with each LSM to determine if differences in land surface parameters impact the LULCC-induced climate responses. Despite clear deficiencies in surface parameters, all LSMs reasonably capture the spatial pattern and magnitude of near-surface temperature and precipitation. However, in the LULCC experiments, inaccuracies in the default LSMs result in illogical localized temperature and precipitation changes. Differences in thermal changes between Noah-MP and CLM-AF indicate that the temperature impacts from LULCC are dependent on the sensitivity of evapotranspiration to LULCC in Sub-Saharan Africa. Errors in land surface parameters indicate that the default WRF LSMs considered are not suitable for LULCC experiments in tropical or Southern Hemisphere regions and that proficient meteorological model performance can mask these issues. We find CLM-AF to be suitable for use in Sub-Saharan Africa LULCC studies, but more work is needed by the WRF community to improve its applicability to other tropical and Southern Hemisphere climates. DA - 2021/6/3/ PY - 2021/6/3/ DO - 10.5194/gmd-14-3215-2021 VL - 14 IS - 6 SP - 3215-3249 SN - 1991-9603 UR - https://doi.org/10.5194/gmd-14-3215-2021 ER - TY - JOUR TI - Projecting changes in extreme rainfall from three tropical cyclones using the design-rainfall approach AU - Jalowska, Anna M. AU - Spero, Tanya L. AU - Bowden, Jared H. T2 - NPJ CLIMATE AND ATMOSPHERIC SCIENCE AB - Abstract In the past quarter-century, Eastern North Carolina (ENC) experienced several devastating tropical cyclones that led to widespread flooding and damage. Historical climate records reflect an increasing trend in the frequency and intensity of extreme rainfall events across the eastern U.S., which is projected to continue to increase throughout the twenty-first century. Potential changes to extreme rainfall across ENC are explored and quantified for 2025–2100 for three tropical cyclones using an approach based on relative changes in future extreme rainfall frequencies (return periods) from dynamically downscaled projections. Maximum rainfall intensities at ‘2100’ could increase locally by 168%, with widespread regional increases in total rainfall up to 44%. Although these magnitudes exceed the consensus in the literature, the values here are comparable to the most extreme rainfall events observed in the U.S. during the early twenty-first century, which suggests that the intensity of projected future events is already a present-day reality. DA - 2021/3/25/ PY - 2021/3/25/ DO - 10.1038/s41612-021-00176-9 VL - 4 IS - 1 SP - SN - 2397-3722 UR - https://doi.org/10.1038/s41612-021-00176-9 ER - TY - JOUR TI - High‐resolution dynamically downscaled rainfall and temperature projections for ecological life zones within Puerto Rico and for the U.S. Virgin Islands AU - Bowden, Jared H. AU - Terando, Adam J. AU - Misra, Vasu AU - Wootten, Adrienne AU - Bhardwaj, Amit AU - Boyles, Ryan AU - Gould, William AU - Collazo, Jaime A. AU - Spero, Tanya L. T2 - International Journal of Climatology AB - The Weather Research and Forecasting (WRF) model and a combination of the Regional Spectral Model (RSM) and the Japanese Meteorological Agency Non-Hydrostatic Model (NHM) were used to dynamically downscale selected CMIP5 global climate models to provide 2-km projections with hourly model output for Puerto Rico and the U.S. Virgin Islands. Two 20-year time slices were downscaled for historical (1986-2005) and future (2041-2060) periods following RCP8.5. Projected changes to mean and extreme temperature and precipitation were quantified for Holdridge life zones within Puerto Rico and for the U.S. Virgin Islands. The evaluation reveals a persistent cold bias for all islands in the U.S. Caribbean, a dry bias across Puerto Rico, and a wet bias on the windward side of mountains within the U.S. Virgin Islands. Despite these biases, model simulations show a robust drying pattern for all islands that is generally larger for Puerto Rico (25% annual rainfall reduction for some life zones) than the U.S. Virgin Islands (12% island average). The largest precipitation reductions are found during the more convectively active afternoon and evening hours. Within Puerto Rico, the model uncertainty increases for the wetter life zones, especially for precipitation. Across the life zones, both models project unprecedented maximum and minimum temperatures that may exceed 200 days annually above the historical baseline with only small changes to the frequency of extreme rainfall. By contrast, in the U.S. Virgin Islands, there is no consensus on the location of the largest drying relative to the windward and leeward side of the islands. However, the models project the largest increases in maximum temperature on the southern side of St. Croix and in higher elevations of St. Thomas and St. John. DA - 2021/2// PY - 2021/2// DO - 10.1002/joc.6810 UR - https://doi.org/10.1002/joc.6810 KW - climate change KW - Puerto Rico KW - regional climate modelling KW - USVI ER -