2008 Progress Report: Ensemble Analyses of the Impact and Uncertainties of Global Change on Regional Air Quality in the U.S.EPA Grant Number: R833369
Title: Ensemble Analyses of the Impact and Uncertainties of Global Change on Regional Air Quality in the U.S.
Investigators: Lamb, Brian , Guenther, Alex , Mass, Clifford , McKenzie, Donald , Salathe, Eric , Theobald, David M. , Wiedinmyer, Christine
Current Investigators: Lamb, Brian , Chung, Sandra , Guenther, Alex , Mass, Clifford , McKenzie, Donald , Salathe, Eric , Wiedinmyer, Christine
Institution: Washington State University , Colorado State University , National Center for Atmospheric Research , USDA Forest Service , University of Washington
Current Institution: Washington State University , National Center for Atmospheric Research , USDA Forest Service , University of Washington
EPA Project Officer: Chung, Serena
Project Period: February 1, 2007 through January 31, 2011 (Extended to January 31, 2012)
Project Period Covered by this Report: February 2, 2008 through February 1,2009
Project Amount: $899,987
RFA: Consequences of Global Change For Air Quality (2006) RFA Text | Recipients Lists
Research Category: Global Climate Change , Climate Change , Air
This proposal builds on results from a previous EPA global change project (RD83830962010). Our overall goal is to answer questions, as initially posed in our previous project, related to the effects of global change on continental and regional air quality AND to include quantitative estimates of uncertainties as part of the answers to our research questions. We will employ an ensemble modeling approach with three specific objectives: 1) to develop a quantitative measure of the uncertainty in our modeling framework using ensemble modeling methods in comparison to current 1995-2004 observations; 2) to project these uncertainties into the future for the period 2045-2054 and quantitatively address the uncertainties that accompany projections of future emissions, both global and U.S., including changes in landcover, urbanization, biogenic emissions, and fire emissions; and 3) to continue to address our research questions that will determine the consequences of global change upon U.S. air quality.
Approach: Our work plan begins with Bayesian analyses of GCM/WRF/CMAQ model configurations for a base climate period (1995-2004) to produce weighted ensemble members based upon their skill in representing observed climate and air quality. This analysis will reduce the number of ensemble members for future climate runs to those that provide significant skill to the overall composite. This reduced set will be combined with a range of potential emission scenarios in a factorial design, to predict both expected values and uncertainties in future air quality. The CMAQ model will enable us to estimate future air quality conditions in terms of photochemical gas ambient concentrations, levels of fine and coarse particulates, and the deposition rates of N, S, and Hg species. Modeling analyses using WRF/CMAQ will address the continental U.S. with 36-km grid resolution and the Pacific Northwest with 12-km grid resolution. An important aspect of the latter scale will be examination of future impacts in Class 1 wilderness areas, as specified in EPA’s Regional Haze Rule.
- WRF simulations have been completed using the 2003 NCEP reanalysis fields for initialization and BC as an evaluation exercise. Analyses of these results is underway.
- CMAQ simulations for the WRF/2003 NCEP run have been completed at the hemispheric scale and are underway for the US continental scale for evaluation purposes.
- Two ensemble members for two decades are underway using the base WRF configuration and two forcing models (ECHAM5 and CCSM3). The present-day (1994-2005) simulations will serve as the basis for model validation in terms of seasonal and annual variability and future (2044-2055) simulations will be examined for regional climate change and local responses in future climate. Simulations for future climate use the IPCC Special Report on Emissions Scenarios (SRES) A1B emissions scenario, which assumes a balanced increase in greenhouse gas concentrations.
- Biogenic emissions using the MEGAN model have been compiled for the hemispheric and continental domains for the NCEP and current decade ECHAM5 simulations.
- Anthropogenic emissions for the hemispheric domain have been compiled and used for the NCEP reanalysis evaluation period and work is underway to compile emissions for the continental domain.
- New land use projections have been developed which are much less extreme than the projected landuse used in our previous project. These will form the basis for projecting future biogenic and anthropogenic emissions.
- Work is underway to apply and evaluate the Fire Scenario Builder using current WRF meteorology to drive the FSB in comparison to the historical fire record.
- Two papers summarizing our results from the first project were submitted to ACPD, reviewed and now have been revised and submitted for final acceptance in ACP.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
|Other project views:||All 16 publications||12 publications in selected types||All 12 journal articles|
||Avise J, Chen J, Lamb B, Wiedinmyer C, Guenther A, Salathe E, Mass C. Attribution of projected changes in summertime US ozone and PM2.5 concentrations to global changes. Atmospheric Chemistry and Physics 2009;9(4):1111-1124.||
||Chen J, Avise J, Lamb B, Salathe E, Mass C, Guenther A, Wiedinmyer C, Lamarque J-F, O'Neill S, McKenzie D, Larkin N. The effects of global changes upon regional ozone pollution in the United States. Atmospheric Chemistry and Physics 2009;9(4):1125-1141.||