Grantee Research Project Results
Final Report: Changes in Climate, Pollutant Emissions, and US Air Quality: An Integrating Modeling Study
EPA Grant Number: R833374Title: Changes in Climate, Pollutant Emissions, and US Air Quality: An Integrating Modeling Study
Investigators: Adams, Peter , Pandis, Spyros N.
Institution: Carnegie Mellon University
EPA Project Officer: Chung, Serena
Project Period: March 1, 2007 through February 28, 2011 (Extended to February 28, 2012)
Project Amount: $896,596
RFA: Consequences of Global Change For Air Quality (2006) RFA Text | Recipients Lists
Research Category: Climate Change , Air
Objective:
The objectives of this project are to understand the potential impacts of climate change on U.S. air quality by performing the following activities with the Global-Regional Climate Air Pollution Modeling System (GRE-CAPS):
- develop a climate-sensitive emissions processor
- update global and regional model simulations of organic aerosol using the volatility basis set approach
- improve treatment of aerosol number and microphysics in regional and global models
- implement a simulation of mercury in the regional component of GRE-CAPS
- develop future climate and emissions scenarios
- assess impact of global change on US air quality focusing on organic aerosol, aerosol microphysics, and mercury
Conclusions:
We summarize the main conclusions of this work for ultrafine particle concentrations, organic aerosol, and mercury.
Ultrafine Particles
- The use of the Fast-TOMAS algorithms speeds up calculations of aerosol microphysics by a factor of ~3 compared to original TOMAS with minimal loss in accuracy, thereby facilitating longer, climate-relevant simulations.
- For accurate simulation of nucleation mode dynamics, it is generally recommended that sectional models use a lower size boundary of 3 nm (or smaller).
- Despite limited scientific understanding of the nucleation and growth (especially due to SOA) processes, our global microphysics model does a reasonably good job in capturing long-term (one year) statistics in nucleation and growth behaviors at 5 sites around the world.
- Our updated emissions in PMCAMx-UF resulted in significant improvement in the ability of the model to reproduce the 50-100 nm ultrafine particle number concentrations in Pittsburgh. There were also improvements in the 10-50 nm size range and relatively small changes in 3-10 nm and >100 nm, where the performance was already good. The overall updated model performance for Pittsburgh can be rated as “good” (mean error based on the criteria used for CTMs).
- Traffic and nucleation were found to be the most important sources of particle number, with their importance varying a significant amount across the Eastern US. The results are consistent with the observation-based estimates of the sources of ultrafine particles in Pittsburgh. Nucleation contributes most to the 3-10 nm range, whereas traffic dominates the 50-100 nm particle numbers. Nucleation contributes 51% to total particle numbers in Pittsburgh, followed by traffic (29%), long-range transport of pollution (18%) and power plant emissions (2%) .
Organic Aerosol
- Implementation of the VBS framework into a global model of organic aerosol allows efficient simulation of the following processes: gas-particle partitioning of semi-volatile POA, formation of SOA from SVOCs and IVOCs, and traditional SOA formation from anthropogenic and biogenic precursors.
- On the global scale, non-traditional SOA formation from the oxidation of SVOCs and IVOCs may produce ~50 Tg yr-1 of SOA.
- The updated global OA model with the processes just listed is able to predict much better the volatility and degree-of-oxygenation of OA compared to traditional OA models that lack these processes.
- Increasing temperature has a variety of effects on organic aerosol concentrations. If temperature alone is increased, bSOA and fPOA will generally evaporate and decrease in concentration. This leads to an average decrease in the South US of 0.4% K-1. While an increase in temperature also causes the evaporation of aSOA and oPOA, the corresponding species continue to react with OH due to chemical aging. This decreases the volatility of the resultant OA components; as a result, an effective increase in the aging aerosols is predicted, leading to an increase in the north of about 0.3% K-1. Making the aging rate constant temperature-sensitive with a high Arrhenius Ea/R value of 500 K resulted in a 0.1% K-1 difference from the TEMP+5 case. The temperature dependence of aerosol aging does not appear to have a significant impact.
- The temperature dependence of biogenic precursor emissions, however, has a critical effect on PMCAMx-2008 OA change predictions. Total aerosol concentrations increased for all augmented biogenic emission cases, up to almost 10% K-1 in some southern cities. The concentration change with temperature for these same cities was fairly consistent with field observations by Leaitch et al. (2011). Increased biogenic emissions also resulted in lower OH concentrations, leading to decreased aging of aSOA and oPOA. These changes due to aging were of a much smaller magnitude than the bSOA concentration increase, however. Repeating these trials with a more realistic biogenic emissions model is recommended for future work.
- Other research shows that biogenic emissions may be limited via plant response to elevated levels of CO2 and changing land use / land cover (Arneth et al., 2008; Heald et al., 2009; Guenther et al., 2006; Chen et al., 2009). Our study only takes into account the temperature effect of climate change, and other factors should be addressed. The potential sensitivity of biogenic systems to climate change in this work, however, suggests that their response will dominate the effects of climate change on air quality.
Mercury
- Our results suggest that climate change will not have a significant effect on Hg0 concentrations. In both periods the predicted temperature increase, which is consistent compare with other modelling studies (Hogrefe et al., 2004; Murazaki and Hess, 2006; Racherla and Adams, 2006), produced a small decrease of Hg0 concentration in most of the model domain, due mainly to the increase of oxidant levels (OH, O3) which favours the oxidation of Hg0.
- Hg2+ levels during summer are predicted to change in the future from -30% to 30% having also a variable spatial trend among the model areas. On a domain average basis Hg2+ levels are predicted to increase in the summertime future by 3%. Increases of Hg2+ are predicted mostly in Southeast (8% on average, up to 45 pg m-3 or 28.5 in Florida) and Midwest (7% on average) areas while a small increase of Hg2+ levels is also predicted in the Plains and in the Northeast. However in several parts of the domain, mainly in TX/OK the changes in Hg2+ concentrations are of the opposite sign of the domain-wide averages. Similar to summer, the predicted response of Hg2+ to climate change during wintertime simulation is also quite variable ranging from -20% to 40%. Hg2+ is predicted to increase over most of the southern parts of the domain (6.6% in Southeast and 5.1% in TX/OK), and also in Midwest (up to 12% in Michigan) and Northeast areas (7.5% on average). On the contrary, there are several areas all over the model domain (e.g. Plains, Indiana), where Hg2+ is going to decrease in the future due to climate change.
- The different response of Hg2+ over the model domain areas, during both simulation periods indicates that several factors could affect Hg2+ concentration, having also a variable contribution over the individual simulation years. The higher future temperature in association with the higher oxidant levels could lead to even more Hg0 to be oxidized and may explain the predicted increase of Hg2+ concentration in some areas. In addition changes in Hg wet deposition caused from changes in precipitation and also ventilation changes as indicated by wind speed could also have a significant effect on Hg2+ response to climate change and should also be taken into account.
- Hg(p) shows a quite similar spatial response to climate change as Hg2+ during summertime. Significant increases of Hg(p) concentration are predicted in Southeast (6% on average), and also in the western part of Midwest (up to 4 pg m-3 or 5.2%), while in TX/OK and in several Midwest and Northeast areas Hg(p) is predicted to decrease in the future.
- Changes in rainfall seem to be the dominant effect on Hg(p) concentration response to climate change, during January. Increases of Hg(p) are predicted in areas located in the Midwest and Northeast, while over most of the southern parts of the domain (TX/OK, Southeast), Hg(p) is predicted to decrease.
- Climate change in the future is predicted to affect also reactive mercury (RHg) total deposition, during both periods. On average, RHg total deposition is predicted to increase by 3% during summer and 5% during winter. Although, among the different Eastern US areas the predicted response to climate change is quite spatially variable ranging from -50% to 50% in the summer and from -30% to 50% during winter. This different response of RHg total deposition to climate change, among the different model areas, is mainly attributed to the predicted spatial-related changes of rainfall rate in the future and the accompanying changes in RHg wet deposition. During summertime increases of RHg total deposition are predicted mainly in the western parts of the domain (9% on average in the Plains and 8% in TX/OK) while mercury deposition is predicted to decrease in the Northeast and also in several areas in the Midwest and Southeast parts of the domain. In the winter increases of RHg total deposition are predicted over a large fraction of Southern areas (13% on average in TX/OK and 5% in the Southeast), while several areas located mainly in Northeast had an opposite trend.
Journal Articles on this Report : 21 Displayed | Download in RIS Format
Other project views: | All 29 publications | 21 publications in selected types | All 21 journal articles |
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Type | Citation | ||
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Dawson JP, Adams PJ, Pandis SN. Sensitivity of PM2.5 to climate in the Eastern US: a modeling case study. Atmospheric Chemistry and Physics 2007;7(16):4295-4309. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit |
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Dawson JP, Racherla PN, Lynn BH, Adams PJ, Pandis SN. Simulating present-day and future air quality as climate changes: model evaluation. Atmospheric Environment 2008;42(19):4551-4566. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit Exit |
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Day MC, Pandis SN. Predicted changes in summertime organic aerosol concentrations due to increased temperatures. Atmospheric Environment 2011;45(36):6546-6556. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit Exit |
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Day MC, Pandis SN. Effects of a changing climate on summertime fine particulate matter levels in the eastern U.S. Journal of Geophysical Research: Atmospheres 2015;120(11):5706-5720. |
R833374 (Final) R835035 (2013) R835035 (Final) |
Exit Exit Exit |
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Farina SC, Adams PJ, Pandis SN. Modeling global secondary organic aerosol formation and processing with the volatility basis set: implications for anthropogenic secondary organic aerosol. Journal of Geophysical Research–Atmospheres 2010;115(D9):D09202. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit Exit |
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Jathar SH, Farina SC, Robinson AL, Adams PJ. The influence of semi-volatile and reactive primary emissions on the abundance and properties of global organic aerosol. Atmospheric Chemistry and Physics 2011;11(15):7727-7746. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) R833748 (2010) R833748 (Final) |
Exit Exit |
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Jung JG, Pandis SN, Adams PJ. Evaluation of nucleation theories in a sulfur-rich environment. Aerosol Science and Technology 2008;42(7):495-504. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit |
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Jung J, Fountoukis C, Adams PJ, Pandis SN. Simulation of in situ ultrafine particle formation in the eastern United States using PMCAMx-UF. Journal of Geophysical Research–Atmospheres 2010;115(D3):D03203 (13 pp.). |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit Exit |
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Lane TE, Donahue NM, Pandis SN. Effect of NOx on secondary organic aerosol concentrations. Environmental Science & Technology 2008;42(16):6022-6027. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit Exit |
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Lane TE, Donahue NM, Pandis SN. Simulating secondary organic aerosol formation using the volatility basis-set approach in a chemical transport model. Atmospheric Environment 2008;42(32):7439-7451. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit Exit |
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Lee YH, Adams PJ. Evaluation of aerosol distributions in the GISS-TOMAS global aerosol microphysics model with remote sensing observations. Atmospheric Chemistry and Physics 2010;10(5):2129-2144. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit |
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Lee YH, Adams PJ. A fast and efficient version of the TwO-Moment Aerosol Sectional (TOMAS) global aerosol microphysics model. Aerosol Science and Technology 2012;46(6):678-689. |
R833374 (Final) |
Exit Exit Exit |
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Lee YH, Pierce JR, Adams PJ. Representation of nucleation mode microphysics in a global aerosol model with sectional microphysics. Geoscientific Model Development 2013;6(4):1221-1232. |
R833374 (Final) |
Exit Exit |
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Megaritis AG, Murphy BN, Racherla PN, Adams PJ, Pandis SN. Impact of climate change on mercury concentrations and deposition in the eastern United States. Science of the Total Environment 2014;487:299-312. |
R833374 (Final) |
Exit Exit Exit |
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Murphy BN, Pandis SN. Simulating the formation of semivolatile primary and secondary organic aerosol in a regional chemical transport model. Environmental Science & Technology 2009;43(13):4722-4728. |
R833374 (Final) R833746 (2008) R833746 (2009) R833746 (2010) R833746 (Final) |
Exit Exit Exit |
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Murphy BN, Pandis SN. Exploring summertime organic aerosol formation in the eastern United States using a regional-scale budget approach and ambient measurements. Journal of Geophysical Research: Atmospheres 115(D24):D24216 (12 pp.). |
R833374 (Final) R833746 (2010) |
Exit Exit Exit |
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Posner LN, Pandis SN. Sources of ultrafine particles in the Eastern United States. Atmospheric Environment 2015;111:103-112. |
R833374 (Final) R835035 (2013) R835035 (Final) R835405 (2014) R835405 (Final) |
Exit Exit Exit |
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Racherla PN, Adams PJ. The response of surface ozone to climate change over the Eastern United States. Atmospheric Chemistry and Physics 2008;8(4):871-885. |
R833374 (2007) R833374 (2008) R833374 (2010) R833374 (Final) |
Exit Exit |
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Weaver CP, Liang X-Z, Zhu J, Adams PJ, Amar P, Avise J, Caughey M, Chen J, Cohen RC, Cooter E, Dawson JP, Gilliam R, Gilliland A, Goldstein AH, Grambsch A, Grano D, Guenther A, Gustafson WI, Harley RA, He S, Hemming B, Hogrefe C, Huang H-C, Hunt SW, Jacob DJ, Kinney PL, Kunkel K, Lamarque J-F, Lamb B, Larkin NK, Leung LR, Liao K-J, Lin J-T, Lynn BH, Manomaiphiboon K, Mass C, McKenzie D, Mickley LJ, O'neill SM, Nolte C, Pandis SN, Racherla PN, Rosenzweig C, Russell AG, Salathe E, Steiner AL, Tagaris E, Tao Z, Tonse S, Wiedinmyer C, Williams A, Winner DA, Woo J-H, Wu S, Wuebbles DJ. A preliminary synthesis of modeled climate change impacts on U.S. regional ozone concentrations. Bulletin of the American Meteorological Society 2009;90(12):1843-1863. |
R833374 (Final) R830960 (Final) R830964 (Final) R833369 (Final) R833370 (Final) R833373 (Final) |
Exit Exit |
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Westervelt DM, Pierce JR, Riipinen I, Trivitayanurak W, Hamed A, Kulmala M, Laaksonen A, Decesari S, Adams PJ. Formation and growth of nucleated particles into cloud condensation nuclei: model-measurement comparison. Atmospheric Chemistry and Physics 2013;13(15):7645-7663. |
R833374 (Final) R835035 (2013) R835035 (Final) |
Exit Exit Exit |
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Westervelt DM, Pierce JR, Adams PJ. Analysis of feedbacks between nucleation rate, survival probability and cloud condensation nuclei formation. Atmospheric Chemistry and Physics 2014;14(11):5577-5597. |
R833374 (Final) R835035 (Final) |
Exit Exit |
Supplemental Keywords:
Air quality modeling, smog, PM, general circulation models, RFA, Scientific Discipline, Air, climate change, Air Pollution Effects, Environmental Monitoring, Atmospheric Sciences, Ecological Risk Assessment, Atmosphere, air quality modeling, particulate matter, atmospheric modelsProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.