Impacts of Global Climate and Emission Changes on U.S. Air Quality

EPA Grant Number: R830963
Title: Impacts of Global Climate and Emission Changes on U.S. Air Quality
Investigators: Liang, Xin-Zhong , Caughey, Michael , Huang, Ho-Chun , Kunkel, Kenneth , Williams, Allen , Wuebbles, Donald J.
Current Investigators: Liang, Xin-Zhong , Caughey, Michael , Hayhoe, Katharine , Huang, Ho-Chun , Kunkel, Kenneth , Lin, Jintai , Patten, Ken , Tao, Zhining , Williams, Allen , Wuebbles, Donald J. , Zhu, Jinhong
Institution: University of Illinois at Urbana-Champaign
EPA Project Officer: Chung, Serena
Project Period: March 23, 2003 through March 22, 2006 (Extended to September 22, 2007)
Project Amount: $900,000
RFA: Assessing the Consequences of Global Change for Air Quality: Sensitivity of U.S. Air Quality to Climate Change and Future Global Impacts (2002) RFA Text |  Recipients Lists
Research Category: Climate Change , Air , Global Climate Change , Air Quality and Air Toxics


The objective of this study is to quantify, and understand the uncertainties of, the individual and combined impacts of global climate and emission changes on U.S. air quality, from the present to 2020, 2050 and 2100. The underlying hypothesis is that U.S. air quality is determined by complex interactions over a range of spatial and temporal scales from (1) chemical processes and emissions on local to regional scales, (2) long-range transport of global pollutants and precursors, and (3) global and regional climate changes and variability. The original contribution of this research will derive from the application of a unique, state-of-the-art integrated modeling system, the components of which the investigators have developed and/or used extensively. The components include a global chemistry-climate model, a high-resolution regional climate model (RCM), and a high-resolution air quality model coupled to the RCM and a detailed regional emissions model. These components, along with access to recent climate simulations from global climate models, provide a complete system for simulating and analyzing the global-regional-local interactions that determine U.S. air quality, focusing on O3 and PM2.5.


We propose to conduct 3 primary sets of experiments. Historical simulations of climate and air quality for 1980-2000 will first be conducted for system validation and for use as a baseline reference for future projections. Future projections for 2020, 2050 and 2100 will then be made, to quantify the individual and combined impacts of global climate and emission changes on US air quality. The 3rd set is sensitivity experiments to determine dominant source regions and types, relative roles of episodic transport vs. mean background levels, as well as uncertainties associated with key conclusions. All experiments will focus on April-October when most adverse air quality episodes occur. Diagnostic studies will identify possible future changes, and their climate and emissions causes, in the frequency, duration, and extreme pollutant concentrations of adverse air quality episodes over the U.S.

Expected Results:

Through the proposed application of this unique modeling system, we will make a major contribution to a key goal of the U.S. EPA Global Change Research Program to quantify the effects of global change on air quality. The advanced state of the components of the modeling system will result in a more complete scientific understanding of the complex scale interactions among climate, global and regional emissions, and U.S. air quality, as well as the uncertainties involved.

Publications and Presentations:

Publications have been submitted on this project: View all 37 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 18 journal articles for this project

Supplemental Keywords:

chemical transport, scale interaction, mobile sources, precipitation, nitrogen oxides, sulfate, particular matter, general circulation models, Great Lakes, Midwest, Northeast, Pacific coast, south central., RFA, Scientific Discipline, Air, Ecosystem Protection/Environmental Exposure & Risk, particulate matter, Air Quality, Air Pollutants, Chemistry, climate change, Air Pollution Effects, Monitoring/Modeling, Atmospheric Sciences, Environmental Engineering, Atmosphere, ambient aerosol, environmental monitoring, anthropogenic stress, atmospheric dispersion models, aerosol formation, atmospheric particulate matter, environmental measurement, meteorology, climatic influence, emissions monitoring, future projections, air quality models, ozone, global change, atmospheric transport, greenhouse gases, climate models, atmospheric aerosol particles, airborne aerosols, environmental stress, regional emissions model, climate model, ecological models, greenhouse gas, aerosols, atmospheric chemistry, climate variability, Global Climate Change, ambient air pollution

Progress and Final Reports:

  • 2003 Progress Report
  • 2004 Progress Report
  • 2005 Progress Report
  • 2006 Progress Report
  • Final Report