2005 Progress Report: Bayesian and Adjoint Inverse Model Analysis of PM Sources in the United States Using Observations from Surface, Aircraft, and Satellite PlatformsEPA Grant Number: R832158
Title: Bayesian and Adjoint Inverse Model Analysis of PM Sources in the United States Using Observations from Surface, Aircraft, and Satellite Platforms
Investigators: Jacob, Daniel J. , Seinfeld, John
Institution: Harvard University , California Institute of Technology
EPA Project Officer: Chung, Serena
Project Period: January 1, 2005 through December 31, 2007 (Extended to December 31, 2008)
Project Period Covered by this Report: January 1, 2005 through December 31, 2006
Project Amount: $450,000
RFA: Source Apportionment of Particulate Matter (2004) RFA Text | Recipients Lists
Research Category: Particulate Matter , Air Quality and Air Toxics , Air
The objective of this research project is to improve knowledge of particulate matter sources in the United States on a continental scale through combined forward, Bayesian, and adjoint inverse model analyses integrating observations from surface sites, aircraft, and satellites.
We have used the Goddard Earth Observing System (GEOS)-Chem global chemical transport model to simulate aircraft observations from the International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) campaign and derive constraints on the sources of carbonaceous aerosols in North America and the influence of boreal fires. We have developed a method to extract quantitative aerosol information from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite observations by diagnosing top-of-atmosphere reflectances from GEOS-Chem model output as influenced by the model aerosol content and comparing those to MODIS reflectances. We have implemented in GEOS-Chem a new mechanism for secondary organic aerosol formation from isoprene and showed it to be an important source of organic carbon aerosol. We have derived an adjoint model of the GEOS-Chem NOx-Ox-HC chemistry simulation including online treatment of several classes of aerosols (elemental carbon, primary organic carbon, SO4-NH4-NO3-H2O). We expect that this work will yield improved source inventories for aerosols in the United States.
During Year 2 of the project, we will: (1) complete our GEOS-Chem model analysis for the ICARTT period with focus on using the constraints from the aircraft and concurrent IMPROVE observations to better understand sources of carbonaceous aerosols in the United States; (2) use comparison of simulated versus observed (MODIS) satellite reflectances as constraints on model aerosol source; and (3) apply an adjoint aerosol model over the United States with a focus on improving emissions inventories of elemental carbon, NH3, SO2, and possibly NOx.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
|Other project views:||All 25 publications||10 publications in selected types||All 10 journal articles|
||van Donkelaar A, Martin RV, Park RJ, Heald CL, Fu T-M, Liao H, Guenther A. Model evidence for a significant source of secondary organic aerosol from isoprene. Atmospheric Environment 2007;41(6):1267-1274.||