References

ACP

Atmospheric Chemistry and Physics

ACP

Atmos. Chem. Phys.

1680-7324

Copernicus Publications

Göttingen, Germany

10.5194/acp-12-3131-2012

Meteorological modes of variability for fine particulate matter (PM2.5) air quality in the United States: implications for PM2.5 sensitivity to climate change

Tai

A. P. K.

¹ Mickley

L. J.

¹ Jacob

D. J.

¹ Leibensperger

E. M.

² Zhang

¹ Fisher

J. A.

¹ Pye

H. O. T.

School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA

Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA

National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, North Carolina, USA

30 03 2012

12 6 3131 3145

2012

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://acp.copernicus.org/articles/12/3131/2012/acp-12-3131-2012.html

The full text article is available as a PDF file from https://acp.copernicus.org/articles/12/3131/2012/acp-12-3131-2012.pdf

We applied a multiple linear regression model to understand the relationships of PM2.5 with meteorological variables in the contiguous US and from there to infer the sensitivity of PM2.5 to climate change. We used 2004–2008 PM2.5 observations from ~1000 sites (~200 sites for PM2.5 components) and compared to results from the GEOS-Chem chemical transport model (CTM). All data were deseasonalized to focus on synoptic-scale correlations. We find strong positive correlations of PM2.5 components with temperature in most of the US, except for nitrate in the Southeast where the correlation is negative. Relative humidity (RH) is generally positively correlated with sulfate and nitrate but negatively correlated with organic carbon. GEOS-Chem results indicate that most of the correlations of PM2.5 with temperature and RH do not arise from direct dependence but from covariation with synoptic transport. We applied principal component analysis and regression to identify the dominant meteorological modes controlling PM2.5 variability, and show that 20–40% of the observed PM2.5 day-to-day variability can be explained by a single dominant meteorological mode: cold frontal passages in the eastern US and maritime inflow in the West. These and other synoptic transport modes drive most of the overall correlations of PM2.5 with temperature and RH except in the Southeast. We show that interannual variability of PM2.5 in the US Midwest is strongly correlated with cyclone frequency as diagnosed from a spectral-autoregressive analysis of the dominant meteorological mode. An ensemble of five realizations of 1996–2050 climate change with the GISS general circulation model (GCM) using the same climate forcings shows inconsistent trends in cyclone frequency over the Midwest (including in sign), with a likely decrease in cyclone frequency implying an increase in PM2.5. Our results demonstrate the need for multiple GCM realizations (because of climate chaos) when diagnosing the effect of climate change on PM2.5, and suggest that analysis of meteorological modes of variability provides a computationally more affordable approach for this purpose than coupled GCM-CTM studies.

References 1

Aw, J. and Kleeman, M. J.: Evaluating the first-order effect of intraannual temperature variability on urban air pollution, J. Geophys. Res.-Atmos., 108, 4365, <a href="http://dx.doi.org/10.1029/2002jd002688">https://doi.org/10.1029/2002jd002688</a>, 2003.

Balkanski, Y. J., Jacob, D. J., Gardner, G. M., Graustein, W. C., and Turekian, K. K.: Transport and residence times of tropospheric aerosols inferred from a global 3-dimensional simulation of pb-210, J. Geophys. Res.-Atmos., 98, 20573–20586, 1993.

Bauer, M. and Del Genio, A. D.: Composite analysis of winter cyclones in a gcm: Influence on climatological humidity, J. Climate, 19, 1652–1672, 2006.

Bengtsson, L., Hodges, K. I., and Roeckner, E.: Storm tracks and climate change, J. Climate, 19, 3518–3543, 2006.

Bertram, T. H., Heckel, A., Richter, A., Burrows, J. P., and Cohen, R. C.: Satellite measurements of daily variations in soil nox emissions, Geophys. Res. Lett., 32, L24812, <a href="http://dx.doi.org/10.1029/2005gl024640">https://doi.org/10.1029/2005gl024640</a>, 2005.

Chen, D., Wang, Y., McElroy, M. B., He, K., Yantosca, R. M., and Le Sager, P.: Regional CO pollution and export in China simulated by the high-resolution nested-grid GEOS-Chem model, Atmos. Chem. Phys., 9, 3825–3839, <a href="http://dx.doi.org/10.5194/acp-9-3825-2009">https://doi.org/10.5194/acp-9-3825-2009</a>, 2009.

Cheng, C. S. Q., Campbell, M., Li, Q., Li, G. L., Auld, H., Day, N., Pengelly, D., Gingrich, S., and Yap, D.: A synoptic climatological approach to assess climatic impact on air quality in south-central canada. Part ii: Future estimates, Water Air Soil Poll., 182, 117–130, 2007.

Christensen, J. H., Hewitson, B., Busuioc, A., Chen, A., Gao, X., Held, I., Jones, R., Kolli, R. K., Kwon, W.-T., Laprise, R., Magana Rueda, V., Mearns, L., Menendez, C. G., Raisanen, J., Rinke, A., Sarr, A., and Whetton, P.: Regional climate projections, in: Climate change 2007: The physical science basis. Contribution of working group i to the fourth assessment report of the intergovernmental panel on climate change, Cambridge University Press, New York, NY, USA, 847–940, 2007.

Chung, S. H. and Seinfeld, J. H.: Global distribution and climate forcing of carbonaceous aerosols, J. Geophys. Res.-Atmos., 107, 4407, <a href="http://dx.doi.org/10.1029/2001jd001397">https://doi.org/10.1029/2001jd001397</a>, 2002.

Cooke, W. F., Liousse, C., Cachier, H., and Feichter, J.: Construction of a 1 degrees × 1 degrees fossil fuel emission data set for carbonaceous aerosol and implementation and radiative impact in the echam4 model, J. Geophys. Res.-Atmos., 104, 22137–22162, 1999.

Cooper, O. R., Moody, J. L., Parrish, D. D., Trainer, M., Ryerson, T. B., Holloway, J. S., Hubler, G., Fehsenfeld, F. C., Oltmans, S. J., and Evans, M. J.: Trace gas signatures of the airstreams within north atlantic cyclones: Case studies from the north atlantic regional experiment (nare '97) aircraft intensive, J. Geophys. Res.-Atmos., 106, 5437–5456, 2001.

Dawson, J. P., Adams, P. J., and Pandis, S. N.: Sensitivity of PM2.5 to climate in the Eastern US: a modeling case study, Atmos. Chem. Phys., 7, 4295–4309, <a href="http://dx.doi.org/10.5194/acp-7-4295-2007">https://doi.org/10.5194/acp-7-4295-2007</a>, 2007.

Day, M. C. and Pandis, S. N.: Predicted changes in summertime organic aerosol concentrations due to increased temperatures, Atmos. Environ., 45, 6546–6556, 2011.

Drury, E., Jacob, D. J., Spurr, R. J. D., Wang, J., Shinozuka, Y., Anderson, B. E., Clarke, A. D., Dibb, J., McNaughton, C., and Weber, R.: Synthesis of satellite (modis), aircraft (icartt), and surface (improve, epa-aqs, aeronet) aerosol observations over eastern north america to improve modis aerosol retrievals and constrain surface aerosol concentrations and sources, J. Geophys. Res.-Atmos., 115, D14204, <a href="http://dx.doi.org/10.1029/2009JD012629">https://doi.org/10.1029/2009JD012629</a>, 2010.

Fang, Y., Fiore, A. M., and Horowitz, L. W.: Impacts of changing transport and precipitation on pollutant distribution in a future climate, J. Geophys. Res.-Atmos., 116, D18303, https://doi.org/10.1029/2011JD015642, 2011.

Fisher, J. A., Jacob, D. J., Wang, Q., Bahreini, R., Carouge, C. C., Cubison, M. J., Dibb, J. E., Diehl, T., Jimenez, J. L., Leibensperger, E. M., Meinders, M. B. J., Pye, H. O. T., Quinn, P. K., Sharma, S., van Donkelaar, A., and Yantosca, R. M.: Sources, distribution, and acidity of sulfate-ammonium aerosol in the arctic in winter-spring, Atmos. Environ., 45, 7301–7318, 2011.

Fountoukis, C. and Nenes, A.: ISORROPIA II: a computationally efficient thermodynamic equilibrium model for K$^+$-Ca$^2+$-Mg$^2+$-NH$_4^+$-Na$^+$-SO$_4^2-$-NO$_3^-$-Cl$^-$-H2O aerosols, Atmos. Chem. Phys., 7, 4639–4659, http://dx.doi.org/10.5194/acp-7-4639-2007https://doi.org/10.5194/acp-7-4639-2007, 2007.

Fu, T. M., Jacob, D. J., and Heald, C. L.: Aqueous-phase reactive uptake of dicarbonyls as a source of organic aerosol over eastern north america, Atmos. Environ., 43, 1814–1822, 2009.

Geng, Q. Z. and Sugi, M.: Variability of the north atlantic cyclone activity in winter analyzed from ncep-ncar reanalysis data, J. Climate, 14, 3863–3873, 2001.

Giglio, L., van der Werf, G. R., Randerson, J. T., Collatz, G. J., and Kasibhatla, P.: Global estimation of burned area using MODIS active fire observations, Atmos. Chem. Phys., 6, 957–974, <a href="http://dx.doi.org/10.5194/acp-6-957-2006">https://doi.org/10.5194/acp-6-957-2006</a>, 2006.

Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P. I., and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181–3210, <a href="http://dx.doi.org/10.5194/acp-6-3181-2006">https://doi.org/10.5194/acp-6-3181-2006</a>, 2006.

Heald, C. L., Jacob, D. J., Park, R. J., Alexander, B., Fairlie, T. D., Yantosca, R. M., and Chu, D. A.: Transpacific transport of asian anthropogenic aerosols and its impact on surface air quality in the united states, J. Geophys. Res.-Atmos., 111, D14310, <a href="http://dx.doi.org/10.1029/2005JD006847">https://doi.org/10.1029/2005JD006847</a>, 2006.

Heald, C. L., Henze, D. K., Horowitz, L. W., Feddema, J., Lamarque, J. F., Guenther, A., Hess, P. G., Vitt, F., Seinfeld, J. H., Goldstein, A. H., and Fung, I.: Predicted change in global secondary organic aerosol concentrations in response to future climate, emissions, and land use change, J. Geophys. Res.-Atmos., 113, D05211, <a href="http://dx.doi.org/10.1029/2007jd009092">https://doi.org/10.1029/2007jd009092</a>, 2008.

Henze, D. K., Seinfeld, J. H., Ng, N. L., Kroll, J. H., Fu, T.-M., Jacob, D. J., and Heald, C. L.: Global modeling of secondary organic aerosol formation from aromatic hydrocarbons: high- vs. low-yield pathways, Atmos. Chem. Phys., 8, 2405–2420, <a href="http://dx.doi.org/10.5194/acp-8-2405-2008">https://doi.org/10.5194/acp-8-2405-2008</a>, 2008.

Holtslag, A. A. M. and Boville, B. A.: Local versus nonlocal boundary-layer diffusion in a global climate model, J. Climate, 6, 1825–1842, 1993.

Jacob, D. J. and Winner, D. A.: Effect of climate change on air quality, Atmos. Environ., 43, 51–63, 2009.

Jacob, D. J., Logan, J. A., Gardner, G. M., Yevich, R. M., Spivakovsky, C. M., Wofsy, S. C., Sillman, S., and Prather, M. J.: Factors regulating ozone over the united-states and its export to the global atmosphere, J. Geophys. Res.-Atmos., 98, 14817–14826, 1993.

Kalnay, E., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D., Gandin, L., Iredell, M., Saha, S., White, G., Woollen, J., Zhu, Y., Chelliah, M., Ebisuzaki, W., Higgins, W., Janowiak, J., Mo, K. C., Ropelewski, C., Wang, J., Leetmaa, A., Reynolds, R., Jenne, R., and Joseph, D.: The ncep/ncar 40-year reanalysis project, B. Am. Meteorol. Soc., 77, 437–471, 1996.

Kistler, R., Kalnay, E., Collins, W., Saha, S., White, G., Woollen, J., Chelliah, M., Ebisuzaki, W., Kanamitsu, M., Kousky, V., van den Dool, H., Jenne, R., and Fiorino, M.: The ncep-ncar 50-year reanalysis: Monthly means cd-rom and documentation, B. Am. Meteorol. Soc., 82, 247–267, 2001.

Kleeman, M. J.: A preliminary assessment of the sensitivity of air quality in california to global change, Climatic Change, 87, S273–S292, <a href="http://dx.doi.org/10.1007/S10584-007-9351-3">https://doi.org/10.1007/S10584-007-9351-3</a>, 2008.

Koch, D., Park, J., and Del Genio, A.: Clouds and sulfate are anticorrelated: A new diagnostic for global sulfur models, J. Geophys. Res.-Atmos., 108, 4781, <a href="http://dx.doi.org/10.1029/2003jd003621">https://doi.org/10.1029/2003jd003621</a>, 2003.

Kutner, M. H., Nachtsheim, C., and Neter, J.: Applied linear regression models, 4th Edn., McGraw-Hill/Irwin, Boston, New York, USA, 701 pp., 2004.

Lam, Y. F., Fu, J. S., Wu, S., and Mickley, L. J.: Impacts of future climate change and effects of biogenic emissions on surface ozone and particulate matter concentrations in the United States, Atmos. Chem. Phys., 11, 4789–4806, <a href="http://dx.doi.org/10.5194/acp-11-4789-2011">https://doi.org/10.5194/acp-11-4789-2011</a>, 2011.

Lambert, S. J. and Fyfe, J. C.: Changes in winter cyclone frequencies and strengths simulated in enhanced greenhouse warming experiments: Results from the models participating in the ipcc diagnostic exercise, Clim. Dynam., 26, 713–728, 2006.

Lang, C. and Waugh, D. W.: Impact of climate change on the frequency of northern hemisphere summer cyclones, J. Geophys. Res.-Atmos., 116, D04103, <a href="http://dx.doi.org/10.1029/2010JD014300">https://doi.org/10.1029/2010JD014300</a>, 2011.

Leibensperger, E. M., Mickley, L. J., and Jacob, D. J.: Sensitivity of US air quality to mid-latitude cyclone frequency and implications of 1980–2006 climate change, Atmos. Chem. Phys., 8, 7075–7086, <a href="http://dx.doi.org/10.5194/acp-8-7075-2008">https://doi.org/10.5194/acp-8-7075-2008</a>, 2008.

Leibensperger, E. M., Mickley, L. J., Jacob, D. J., Chen, W.-T., Seinfeld, J. H., Nenes, A., Adams, P. J., Streets, D. G., Kumar, N., and Rind, D.: Climate effects of 1950–2050 changes in us anthropogenic aerosols – part 1: Aerosol trends and radiative forcing, Atmos. Chem. Phys., accepted, 2011a.

Leibensperger, E. M., Mickley, L. J., Jacob, D. J., Chen, W.-T., Seinfeld, J. H., Nenes, A., Adams, P. J., Streets, D. G., Kumar, N., and Rind, D.: Climate effects of 1950–2050 changes in us anthropogenic aerosols – part 2: Climate response, Atmos. Chem. Phys., in press, 2011b.

Li, Q. B., Jacob, D. J., Park, R., Wang, Y. X., Heald, C. L., Hudman, R., Yantosca, R. M., Martin, R. V., and Evans, M.: North american pollution outflow and the trapping of convectively lifted pollution by upper-level anticyclone, J. Geophys. Res.-Atmos., 110, D10301, <a href="http://dx.doi.org/10.1029/2004jd005039">https://doi.org/10.1029/2004jd005039</a>, 2005.

Liao, H., Chen, W. T., and Seinfeld, J. H.: Role of climate change in global predictions of future tropospheric ozone and aerosols, J. Geophys. Res.-Atmos., 111, D12304, <a href="http://dx.doi.org/10.1029/2005jd006852">https://doi.org/10.1029/2005jd006852</a>, 2006.

Liao, H., Henze, D. K., Seinfeld, J. H., Wu, S. L., and Mickley, L. J.: Biogenic secondary organic aerosol over the united states: Comparison of climatological simulations with observations, J. Geophys. Res.-Atmos., 112, D06201, <a href="http://dx.doi.org/10.1029/2006jd007813">https://doi.org/10.1029/2006jd007813</a>, 2007.

Lin, J. T. and McElroy, M. B.: Impacts of boundary layer mixing on pollutant vertical profiles in the lower troposphere: Implications to satellite remote sensing, Atmos. Environ., 44, 1726–1739, 2010.

Liu, H. Y., Jacob, D. J., Bey, I., and Yantosca, R. M.: Constraints from pb-210 and be-7 on wet deposition and transport in a global three-dimensional chemical tracer model driven by assimilated meteorological fields, J. Geophys. Res.-Atmos., 106, 12109–12128, 2001.

Mickley, L. J., Jacob, D. J., Field, B. D., and Rind, D.: Effects of future climate change on regional air pollution episodes in the united states, Geophys. Res. Lett., 31, L24103, <a href="http://dx.doi.org/10.1029/2004gl021216">https://doi.org/10.1029/2004gl021216</a>, 2004.

Murazaki, K. and Hess, P.: How does climate change contribute to surface ozone change over the united states?, J. Geophys. Res.-Atmos., 111, D05301, <a href="http://dx.doi.org/10.1029/2005jd005873">https://doi.org/10.1029/2005jd005873</a>, 2006.

Nakicenovic, N. and Swart, R.: Special report on emissions scenarios: A special report of working group iii of the intergovernmental panel on climate change, Cambridge University Press, Cambridge, New York, USA, 599 pp., 2000.

Park, R. J., Jacob, D. J., Field, B. D., Yantosca, R. M., and Chin, M.: Natural and transboundary pollution influences on sulfate-nitrate-ammonium aerosols in the united states: Implications for policy, J. Geophys. Res.-Atmos., 109, D15204, <a href="http://dx.doi.org/10.1029/2003jd004473">https://doi.org/10.1029/2003jd004473</a>, 2004.

Park, R. J., Jacob, D. J., Kumar, N., and Yantosca, R. M.: Regional visibility statistics in the united states: Natural and transboundary pollution influences, and implications for the regional haze rule, Atmos. Environ., 40, 5405–5423, 2006.

Park, R. J., Jacob, D. J., and Logan, J. A.: Fire and biofuel contributions to annual mean aerosol mass concentrations in the united states, Atmos. Environ., 41, 7389–7400, 2007.

Pinder, R. W., Pekney, N. J., Davidson, C. I., and Adams, P. J.: A process-based model of ammonia emissions from dairy cows: Improved temporal and spatial resolution, Atmos. Environ., 38, 1357–1365, 2004.

Pinto, J. G., Ulbrich, U., Leckebusch, G. C., Spangehl, T., Reyers, M., and Zacharias, S.: Changes in storm track and cyclone activity in three sres ensemble experiments with the echam5/mpi-om1 gcm, Clim. Dynam., 29, 195–210, 2007.

Pye, H. O. T., Liao, H., Wu, S., Mickley, L. J., Jacob, D. J., Henze, D. K., and Seinfeld, J. H.: Effect of changes in climate and emissions on future sulfate-nitrate-ammonium aerosol levels in the united states, J. Geophys. Res.-Atmos., 114, D01205, <a href="http://dx.doi.org/10.1029/2008jd010701">https://doi.org/10.1029/2008jd010701</a>, 2009.

Rasmussen, D. J., Fiore, A. M., Naik, V., Horowitz, L. W., McGinnis, S. J., and Schultz, M. G.: Surface ozone-temperature relationships in the eastern us: A monthly climatology for evaluating chemistry-climate models, Atmos. Environ., 47, 142–153, <a href="http://dx.doi.org/10.1016/j.atmosenv.2011.11.021">https://doi.org/10.1016/j.atmosenv.2011.11.021</a>, 2012.

Rind, D., Lerner, J., Jonas, J., and McLinden, C.: Effects of resolution and model physics on tracer transports in the nasa goddard institute for space studies general circulation models, J. Geophys. Res.-Atmos., 112, D09315, <a href="http://dx.doi.org/10.1029/2006jd007476">https://doi.org/10.1029/2006jd007476</a>, 2007.

Sheehan, P. E. and Bowman, F. M.: Estimated effects of temperature on secondary organic aerosol concentrations, Environ. Sci. Technol., 35, 2129–2135, 2001.

Sillman, S. and Samson, F. J.: Impact of temperature on oxidant photochemistry in urban, polluted rural and remote environments, J. Geophys. Res.-Atmos., 100, 11497–11508, 1995.

Spracklen, D. V., Mickley, L. J., Logan, J. A., Hudman, R. C., Yevich, R., Flannigan, M. D., and Westerling, A. L.: Impacts of climate change from 2000 to 2050 on wildfire activity and carbonaceous aerosol concentrations in the western united states, J. Geophys. Res.-Atmos., 114, D20301, <a href="http://dx.doi.org/10.1029/2008jd010966">https://doi.org/10.1029/2008jd010966</a>, 2009.

Stelson, A. W. and Seinfeld, J. H.: Relative-humidity and temperature-dependence of the ammonium-nitrate dissociation-constant, Atmos. Environ., 16, 983–992, 1982.

Tai, A. P. K., Mickley, L. J., and Jacob, D. J.: Correlations between fine particulate matter (pm2.5) and meteorological variables in the united states: Implications for the sensitivity of pm2.5 to climate change, Atmos. Environ., 44, 3976–3984, 2010.

Thishan Dharshana, K. G., Kravtsov, S., and Kahl, J. D. W.: Relationship between synoptic weather disturbances and particulate matter air pollution over the united states, J. Geophys. Res.-Atmos., 115, D24219, <a href="http://dx.doi.org/10.1029/2010jd014852">https://doi.org/10.1029/2010jd014852</a>, 2010.

van Donkelaar, A., Martin, R. V., and Park, R. J.: Estimating ground-level pm(2.5) using aerosol optical depth determined from satellite remote sensing, J. Geophys. Res.-Atmos., 111, D21201, <a href="http://dx.doi.org/10.1029/2005JD006996">https://doi.org/10.1029/2005JD006996</a>, 2006.

van Donkelaar, A., Martin, R. V., Leaitch, W. R., Macdonald, A. M., Walker, T. W., Streets, D. G., Zhang, Q., Dunlea, E. J., Jimenez, J. L., Dibb, J. E., Huey, L. G., Weber, R., and Andreae, M. O.: Analysis of aircraft and satellite measurements from the Intercontinental Chemical Transport Experiment (INTEX-B) to quantify long-range transport of East Asian sulfur to Canada, Atmos. Chem. Phys., 8, 2999–3014, <a href="http://dx.doi.org/10.5194/acp-8-2999-2008">https://doi.org/10.5194/acp-8-2999-2008</a>, 2008.

Wang, Y. H., Jacob, D. J., and Logan, J. A.: Global simulation of tropospheric o-3-nox-hydrocarbon chemistry 1. Model formulation, J. Geophys. Res.-Atmos., 103, 10713–10725, 1998.

Weaver, C. P., Liang, X. Z., Zhu, J., Adams, P. J., Amar, P., Avise, J., Caughey, M., Chen, J., Cohen, R. C., Cooter, E., Dawson, J. P., Gilliam, R., Gilliland, A., Goldstein, A. H., Grambsch, A., Grano, D., Guenther, A., Gustafson, W. I., Harley, R. A., He, S., Hemming, B., Hogrefe, C., Huang, H. C., Hunt, S. W., Jacob, D. J., Kinney, P. L., Kunkel, K., Lamarque, J. F., Lamb, B., Larkin, N. K., Leung, L. R., Liao, K. J., Lin, J. T., Lynn, B. H., Manomaiphiboon, K., Mass, C., McKenzie, D., Mickley, L. J., O'Neill, S. M., Nolte, C., Pandis, S. N., Racherla, P. N., Rosenzweig, C., Russell, A. G., Salathe, E., Steiner, A. L., Tagaris, E., Tao, Z., Tonse, S., Wiedinmyer, C., Williams, A., Winner, D. A., Woo, J. H., Wu, S., and Wuebbles, D. J.: A preliminary synthesis of modeled climate change impacts on us regional ozone concentrations, B. Am. Meteorol. Soc., 90, 1843–1863, 2009.

Wesely, M. L.: Parameterization of surface resistances to gaseous dry deposition in regional-scale numerical-models, Atmos. Environ., 23, 1293–1304, 1989.

Wilks, D. S.: Statistical methods in the atmospheric sciences, 2nd edn., International geophysics series, 91, Academic Press, Amsterdam, Boston, xvii, 627 pp., 2006.

Wise, E. K. and Comrie, A. C.: Meteorologically adjusted urban air quality trends in the southwestern united states, Atmos. Environ., 39, 2969–2980, 2005.

Wu, S., Mickley, L. J., Leibensperger, E. M., Jacob, D. J., Rind, D., and Streets, D. G.: Effects of 2000–2050 global change on ozone air quality in the united states, J. Geophys. Res.-Atmos., 113, D06302, <a href="http://dx.doi.org/10.1029/2007jd008917">https://doi.org/10.1029/2007jd008917</a>, 2008.

Yienger, J. J. and Levy, H.: Empirical-model of global soil-biogenic NO$_{\rm x}$ emissions, J. Geophys. Res.-Atmos., 100, 11447–11464, 1995.

Zhang, L., Jacob, D. J., Downey, N. V., Wood, D. A., Blewitt, D., Carouge, C. C., van Donkelaar, A., Jones, D. B. A., Murray, L. T., and Wang, Y. X.: Improved estimate of the policy-relevant background ozone in the united states using the geos-chem global model with 1/2 degrees x 2/3 degrees horizontal resolution over north america, Atmos. Environ., 45, 6769–6776, <a href="http://dx.doi.org/10.1016/J.Atmosenv.2011.07.054">https://doi.org/10.1016/J.Atmosenv.2011.07.054</a>, 2011.

Zhang, L., Jacob, D. J., Knipping, E. M., Kumar, N., Munger, J. W., Carouge, C. C., van Donkelaar, A., Wang, Y. X., and Chen, D.: Nitrogen deposition to the United States: distribution, sources, and processes, Atmos. Chem. Phys. Discuss., 12, 241–282, <a href="http://dx.doi.org/10.5194/acpd-12-241-2012">https://doi.org/10.5194/acpd-12-241-2012</a>, 2012.