Grantee Research Project Results

Final Report: Regional Air Quality Management Aspects of Global Change: Impact of Climate-ResponsiveControls and Forest Management Practices on Regional Air Quality and Associated Uncertainties

EPA Grant Number: R834281
Title: Regional Air Quality Management Aspects of Global Change: Impact of Climate-ResponsiveControls and Forest Management Practices on Regional Air Quality and Associated Uncertainties
Investigators: Russell, Armistead G. , Bergin, Michelle S. , Wang, Y. T. , Tsimpidi, A.P. , Nenes, Athanasios , Tian, D. , Klieman, G. , Yang, H. , Rudokas, J. , Fahey, K. , Tsigaridis, K. , Trail, M. , Liu, P. , Amar, Praveen , Hu, Y.T.
Institution: Georgia Institute of Technology , Georgia Environmental Protection Division , NESCAUM , NASA Goddard Institute for Space Studies
Current Institution: Georgia Environmental Protection Division , Georgia Institute of Technology , NASA Goddard Institute for Space Studies , NESCAUM
EPA Project Officer: Chung, Serena
Project Period: October 1, 2009 through September 30, 2012 (Extended to September 30, 2013)
Project Amount: $599,963
RFA: Adaptation for Future Air Quality Analysis and Decision Support Tools in Light of Global Change Impacts and Mitigation (2008) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Climate Change , Air

Objective:

As described in the proposal for this grant, testing the following specific hypotheses motivates scientific design of this study:

• Choices of climate-responsive controls (e.g., CCS, improved generation and transmission efficiencies, reduced petroleum fuel/increased low-carbon fuels use for transportation sector, a large collection of measures related to increased enduse energy efficiency in various industrial, commercial, residential, and transportation sectors) can positively impact air quality, enhancing the extent of their benefits, while others (e.g., production and use of biomass-derived liquid fuels) may not.

• Forest management and utilization practices will become a major factor determining future PM and ozone levels, particularly in the Southeast.

• Reforestation associated with increased biomass fuel production will reduce temperatures in the Southeast, and ozone and PM concentrations.

• Climate changes will not significantly impact “Policy-Relevant Background (PRB) levels of ozone or PM2.5.

The overarching objective of this study is to provide information as to which global change-related control choices and forest management and utilization practices are most effective for both mitigating climate change and improving regional air quality. Four specific objectives are identified to address critical scientific issues linking global change with assessment of regional air quality and forest management practices:

• Assess and compare how climate-responsive control choices will affect regional air quality

• Assess how forest management and utilization practices will impact future regional climate and air quality

• Quantify the sensitivities and dominant uncertainties associated with predicted impacts

• Provide focused information for policy makers on the impact of climate change/global change on strategies to meet air quality policy goals in the future, including providing results for direct use in decision support analyses.

We have simulated how future air quality will respond to climate-responsive management approaches using CMAQ and WRF as our primary atmospheric simulation platforms, with a future target period of 2048-2052. EPA MARKAL 9R [Fishbone et al., 1980] was used to identify future technology changes responding to climate-responsive controls in various sectors treated by MARKAL. SMOKE was used for emissions processing. We also developed potential future forest and cropland use scenarios to test their impacts on climate and air quality.

Summary/Accomplishments (Outputs/Outcomes):

In conducting sensitivity simulations for present and future reference emissions scenarios, we found that current air pollution control strategies will continue to be effective despite climate change [Trail, 2013d]:

“Reductions in mobile and point source emissions account for reduced PM2.5 concentration while climate change reinforces the reduced concentrations during the spring, summer and fall. Future decreases in MDA8 mixing ratio are mainly attributed to decreased emissions rate of VOC and NOX from mobile sources. Reduced emissions are predicted to decrease MDA8 despite the tendency for climate change to increase MDA8 mixing ratio.”

In Trail et al. [Trail, 2013e], we tested the impact of the following four alternative climate-mitigation strategies on air quality:

Scenario	Description
Reference Case	• Clean Air Act Title IV (Acid Rain Program) SO2 and NOx requirements • Clean Air Interstate Rule • Utility Mercury and Air Toxics Standards (MATS) • Aggregated state Renewable Portfolio Standards (RPS) standards by region • Federal Corporate Average Fuel Economy (CAFE) standards as modeled in AEO 2012 • Tier 2 light duty vehicle tailpipe emission standards • Heavy duty vehicle fuel and engine rules
CT1 (Carbon Tax 1)	• Carbon tax of $20 per ton beginning in 2015 and increasing at a rate of 4% per year ($90 per ton in 2050)
CT2 (Carbon Tax 2)	• Carbon tax of $50 per ton beginning in 2020 and increasing at a rate of 10% per year ($1,400 per ton in 2050)
TN (Transportation)	• 70% reduction in GHG emissions from the transportation sector by 2050 relative to 2005 levels • Limit CO2 emission rate from electricity sector to 800 lb/MWh (similar to that of a new combined cycle natural gas power plant)
BM (Biomass)	• All available biomass in the U.S. is used (includes agricultural residues, energy crops, mill residues and urban wood waste)

Overall, we found in [Trail, 2013e]:

“two potential climate change mitigation policies (CT1 and BM) which can lead to worse air quality, in the form of increased PM2.5 concentration, compared to the 2050 reference case and two policies which lead to some improvements compared to the 2050 reference case (CT2 and TN). While the CT2 scenario caused decreased concentrations of PM2.5 over much of the Eastern U.S. and in the major cities, O3 concentration increased due to the carbon tax. Similar conflicting air quality arose in the TN scenario where O3 and PM2.5 concentrations decreased over most of the U.S. but PM2.5 in urban areas increased because of increased OM concentration.”

We also that reforestation tends to decrease O3 while increasing summertime PM2.5 in the Southeast while conversion of forest to cropland tends to increase both O3 and PM2.5 year-round” [Trail, 2013a].

“Reforestation

The impacts on future air quality as a result of potential reforestation are simulated by converting all Southeast cropland to forest in the input files to WRF, SMOKE and CMAQ and comparing O3 and PM2.5 concentrations to the reference land use case. The 4th highest mean daily 8-hr average (MDA8) O3 mixing ratio of the year, which is the metric used to determine if an area is in non-attainment according to the NAAQS standard (non-attainment is 75 ppb), decreases by up to 10 ppb from the reference case 4th highest MDA8 (between 50 and 70 ppb) in the Southeast U.S. due to reforestation… Summertime (JJA) average PM2.5 concentration increases of around 1 ug m-3 occur over the Southeast due to reforestation of croplands with the largest increases over the Mississippi river and in Georgia and South Carolina…

Cropland Conversion

Conversion of forest to cropland in the Southeast leads to increases in 4th highest MDA8 mixing ratio in Mississippi, Alabama, Georgia, and South Carolina of up to 10 ppb. Cropland emits NOX at a much higher rate than forest, leading to increased production of O3 in the atmosphere…

Seasonal average PM2.5 concentration over the Southeast domain increases of up to 1.5 ug m-3 occur in the cropland conversion scenario. During the summer, sulfate aerosol average over the Southeast domain increases by 0.67 ug m-3 while OM aerosol decreases by 0.41 ug m-3. The decreased OM results form lower emissions of organic compounds, such as isoprene, from crops than from forests”

Conclusions:

We investigated the impacts of potential climate-mitigation strategies, reforestation and cropland conversion on future regional air quality using meteorology downscaled from a general circulation model by WRF and emissions processed by SMOKE as inputs to CMAQ. The methods and model configuration used in these studies proved to be useful and efficient at providing relevant results. Decision makers should be aware, though, that decreased emissions of NOX in some polluted cities such as Los Angeles could lead to increased O3. However, as these cities become more NOX

limited, further reductions in NOX emissions in these urban environments will lead to lower levels of O3. We also found that climate-mitigation strategies aimed at reducing emissions from the transportation sector while improving electricity generation efficiency are most effective at improving overall O3 and PM2.5 air quality. On the other hand, biomass and light carbon tax policies may worsen air quality.

We explore how altered precursor biogenic emissions, deposition rates and meteorology associated with reforestation and cropland conversion influence O3 and PM2.5. In conducting the land use change simulations, we note the importance in understanding the uncertainty associated with vegetation parameters such as the stomatal resistance when simulating the impact of agricultural impacts on regional climate and air quality. The results of the reforestation and cropland conversion studies show that climate and O3 and aerosol concentrations are highly sensitive to reforestation and cropland conversion in the Southeast and these land use changes should be considered in air quality management plans.

Journal Articles on this Report : 5 Displayed | Download in RIS Format

Publications Views
Other project views:	All 14 publications	5 publications in selected types	All 5 journal articles

Publications
Type	Citation	Project	Document Sources
Journal Article	Liu P, Tsimpidi AP, Hu Y, Stone B, Russell AG, Nenes A. Differences between downscaling with spectral and grid nudging using WRF. Atmospheric Chemistry and Physics 2012;12(8):3601-3610.	R834281 (2011) R834281 (2012) R834281 (Final)	Full-text: ACP-Full text PDF Exit Abstract: ACP-Abstract Exit
Journal Article	Rudokas J, Miller PJ, Trail MA, Russell AG. Regional air quality management aspects of climate change:impact of climate mitigation options on regional air emissions. Environmental Science & Technology 2015;49(8):5170-5177.	R834281 (Final)	Abstract from PubMed Full-text: ES&T-Full Text HTML Exit Abstract: ES&T-Abstract Exit Other: ES&T-Full Text PDF Exit
Journal Article	Trail M, Tsimpidi AP, Liu P, Tsigaridis K, Hu Y, Nenes A, Stone B, Russell AG. Potential impact of land use change on future regional climate in the Southeastern U.S.:reforestation and crop land conversion. Journal of Geophysical Research: Atmospheres 2013;118(20):11577-11588.	R834281 (Final)	Full-text: Wiley-Full Text HTML Exit Abstract: Wiley-Abstract Exit Other: Wiley-Full Text PDF Exit
Journal Article	Trail M, Tsimpidi AP, Liu P, Tsigaridis K, Hu Y, Nenes A, Russell AG. Downscaling a global climate model to simulate climate change over the US and the implication on regional and urban air quality. Geoscientific Model Development 2013;6(5):1429-1445.	R834281 (Final)	Full-text: Geoscientific Model Development-Full Text PDF Exit Abstract: Geoscientific Model Development-Abstract Exit
Journal Article	Trail M, Tsimpidi AP, Liu P, Tsigaridis K, Hu Y, Nenes A, Stone B, Russell AG. Reforestation and crop land conversion impacts on future regional air quality in the Southeastern U.S. Agricultural and Forest Meteorology 2015;209-210:78-86.	R834281 (Final)	Full-text: ScienceDirect-Full Text HTML Exit Abstract: ScienceDirect-Abstract Exit Other: ScienceDirect-Full Text PDF Exit

Supplemental Keywords:

Future air quality, downscaling, regional climate, energy sector emissions, climate-mitigation, land use/land cover, biogenic emissions, WRF, CMAQ-DDM, CMAQ, RFA, Scientific Discipline, Air, POLLUTION PREVENTION, Energy, climate change, Air Pollution Effects, Environmental Monitoring, Atmosphere, atmospheric nitrogen, particulate matter, decision making, energy efficiency, environmental policy, forests, deforestation, ecosystem sustainability, air quality, Global Climate Change

Progress and Final Reports:

Original Abstract

The 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.