@article{tong_mathur_kang_yu_schere_pouliot_2009, title={Vegetation exposure to ozone over the continental United States: Assessment of exposure indices by the Eta-CMAQ air quality forecast model}, volume={43}, ISSN={["1873-2844"]}, DOI={10.1016/j.atmosenv.2008.09.084}, abstractNote={The main use of air quality forecast (AQF) models is to predict ozone (O3) exceedances of the primary O3 standard for informing the public of potential health concerns. This study presents the first evaluation of the performance of the Eta-CMAQ air quality forecast model to predict a variety of widely used seasonal mean and cumulative O3 exposure indices associated with vegetation using the U.S. AIRNow O3 observations. These exposure indices include two concentration-based O3 indices, M7 and M12 (the seasonal means of daytime 7-h and 12-h O3 concentrations, respectively), and three cumulative exposure-based indices, SUM06 (the sum of all hourly O3 concentrations ≥ 0.06 ppm), W126 (hourly concentrations weighed by a sigmoidal weighting function), and AOT40 (O3 concentrations accumulated over a threshold of 40 ppb during daylight hours). During a three-month simulation (July–September 2005), the model over predicted the M7 and M12 values by 8–9 ppb, or a NMB value of 19% and a NME value of 21%. The model predicts a central belt of high O3 extending from Southern California to Middle Atlantic where the seasonal means, M7 and M12 (the seasonal means of daytime 7-h and 12-h O3 concentrations), are higher than 50 ppbv. In contrast, the model is less capable of reproducing the observed cumulative indices. For AOT40, SUM06 and W126, the NMB and NME values are two- to three-fold of that for M7, M12 or peak 8-h O3 concentrations. The AOT40 values range from 2 to 33 ppm h by the model and from 1 to 40 ppm h by the monitors. There is a significantly higher AOT40 value experienced in the United States in comparison to Europe. The domain-wide mean SUM06 value is 14.4 ppm h, which is about 30% higher than W126, and 40% higher than AOT40 calculated from the same 3-month hourly O3 data. This suggests that SUM06 and W126 represent a more stringent standard than AOT40 if either the SUM06 or the W126 was used as a secondary O3 standard. Although CMAQ considerably over predicts SUM06 and W126 values at the low end, the model under predicts the extreme high exposure values (>50 ppm h). Most of these extreme high values are found at inland California sites. Based on our analysis, further improvement of the model is needed to better capture cumulative exposure indices.}, number={3}, journal={ATMOSPHERIC ENVIRONMENT}, author={Tong, Daniel Q. and Mathur, Rohit and Kang, Daiwen and Yu, Shaocai and Schere, Kenneth L. and Pouliot, George}, year={2009}, month={Jan}, pages={724–733} }
 @article{kang_aneja_mathur_ray_2004, title={Observed and modeled VOC chemistry under high VOC/NOx conditions in the Southeast United States national parks}, volume={38}, ISSN={["1352-2310"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-4043070651&partnerID=MN8TOARS}, DOI={10.1016/j.atmosenv.2004.05.054}, abstractNote={In airsheds that contain high volatile organic compounds (VOCs) and low NOx (=NO+NO2) concentrations, ozone (O3) production may be significantly suppressed by NOx reactions that lead to the formation of organic nitrates. O3 and its precursors (VOCs and NOx) ambient levels simulated using a regional-scale photochemical model, called Multiscale Air Quality Simulation Platform, are analyzed and compared to observed data from three southeast United States national parks.}, number={29}, journal={ATMOSPHERIC ENVIRONMENT}, author={Kang, DW and Aneja, VP and Mathur, R and Ray, JD}, year={2004}, month={Sep}, pages={4969–4974} }
 @article{aneja_mathur_arya_li_murray_manuszak_2000, title={Coupling the vertical distribution of ozone in the atmospheric boundary layer}, volume={34}, ISSN={["0013-936X"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0034195280&partnerID=MN8TOARS}, DOI={10.1021/es990997+}, abstractNote={Vertical measurements of ozone were made on a 610 m tall tower located about 15 km southeast of Raleigh, NC, as part of an effort by the State of North Carolina to develop a State Implementation Plan (SIP) for ozone control in the Raleigh Metropolitan Statistical Area and other metropolitan areas in the state. Ozone was monitored at 10, 250, and 433 m height levels during the summer months of 1993−1995 and at 10, 76, 128, and 433 m height levels during the summer months of 1996−1997. A regional atmospheric chemistry/transport model, called Multiscale Air Quality Simulation Platform (MAQSIP), was also employed to simulate three-dimensional O3 distribution over the eastern United States for a 2-month period (June 1−July 31, 1995). Through complementary analyses of the 5-year data and the modeling results, this paper examines the vertical distribution of ozone concentrations in the atmospheric boundary layer with the emphasis on the contribution of residual ozone aloft to the ground level ozone enhancement d...}, number={11}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Aneja, VP and Mathur, R and Arya, SP and Li, YX and Murray, GC and Manuszak, TL}, year={2000}, month={Jun}, pages={2324–2329} }
 @article{faluvegi_alapaty_reichle_mathur_raman_connors_1999, title={Simulation of carbon monoxide transport during April 1994}, volume={104}, ISSN={["2169-8996"]}, DOI={10.1029/1998JD100030}, abstractNote={The Multiscale Air Quality Simulation Platform (MAQSIP) is used to simulate transport of carbon monoxide (CO) as a passive tracer over North America, Europe, and the North Atlantic during the April 1994 Measurement of Air Pollution from Satellites (MAPS) mission. MAQSIP is driven by meteorological fields generated by the Pennsylvania State University/National Center for Atmospheric Research fifth‐generation mesoscale model. Model CO surface emissions from biomass burning, fossil fuel combustion, nonmethane hydrocarbon oxidation, oceans, and soils are based on inventories from the Belgian Institute for Space Aeronomy and the Global Emissions Inventory Activity. Predicted CO mixing ratios are vertically weighted for comparison with MAPS observations. The spread in the mission‐averaged vertically weighted simulated CO mixing ratios (∼38 ppbv, compared to 60 ppbv in the MAPS data) suggests that CO surface emissions significantly affect MAPS observations on a weekly timescale. Good qualitative agreement is found between MAPS observations and model predictions on several temporal and spatial scales. Possible reasons for discrepancies are examined. A simulation without cumulus convection increases CO mixing ratios in the lower model layers and depletes CO above, resulting in a complex pattern of increases and decreases upon vertical weighted integration. Another simulation, which included a diurnal emissions variation, produced significant changes in instantaneous local CO mixing ratios, but had a minimal effect on the mission‐averaged MAPS comparisons.}, number={D17}, journal={JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES}, author={Faluvegi, GS and Alapaty, K and Reichle, HG and Mathur, R and Raman, S and Connors, VS}, year={1999}, month={Sep}, pages={21471–21485} }