2005 Progress Report: Bayesian and Adjoint Inverse Model Analysis of PM Sources in the United States Using Observations from Surface, Aircraft, and Satellite Platforms

EPA 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.

Progress Summary:

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.

Future Activities:

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
Type Citation Project Document Sources
Journal Article 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. R832158 (2005)
R832158 (Final)
  • Full-text: Science Direct-Full Text HTML
  • Abstract: Science Direct-Abstract
  • Other: Science Direct-Full Text PDF
  • Supplemental Keywords:

    particulate matter, PM2.5, adjoint inverse model analysis, advanced factor analysis models, aerosol analyzers, aerosol optical depth data, aerosol particles, air quality model, air quality models, air sampling, airborne particulate matter, atmospheric dispersion models, atmospheric measurements, carbon particles, carbonaceous particulate matter, chemical characteristics, chemical speciation sampling, diesel exhaust, emissions monitoring, environmental measurement, mobile sources, model-based analysis, modeling studies, particle size measurement, particulate matter mass, particulate organic carbon, positive matrix factorization,, RFA, Scientific Discipline, Air, Ecosystem Protection/Environmental Exposure & Risk, RESEARCH, particulate matter, Environmental Chemistry, Monitoring/Modeling, Monitoring, Environmental Monitoring, Ecological Risk Assessment, Environmental Engineering, remote sensing, atmospheric dispersion models, particulate organic carbon, atmospheric measurements, model-based analysis, chemical characteristics, environmental measurement, positive matrix factorization, emissions monitoring, air quality models, airborne particulate matter, diesel exhaust, air sampling, carbon particles, air quality model, adjoint inverse model analysis, mobile sources, particulate matter mass, PM2.5, modeling studies, aersol particles, aerosol optical depth data, aerosol analyzers, chemical speciation sampling, particle size measurement, carbonaceous particulate matter

    Relevant Websites:

    http://www.as.harvard.edu/chemistry/trop/index.html Exit
    http://www.che.caltech.edu/faculty/seinfeld_j/research.html Exit

    Progress and Final Reports:

    Original Abstract
  • 2006 Progress Report
  • 2007 Progress Report
  • Final Report