Grantee Research Project Results
2004 Progress Report: Atmospheric Aerosols from Biogenic Hydrocarbon Oxidation
EPA Grant Number: R831079Title: Atmospheric Aerosols from Biogenic Hydrocarbon Oxidation
Investigators: Milford, Jana B. , Guenther, Alex , Wiedinmyer, Christine , Helmig, Detlev
Institution: University of Colorado at Boulder , National Center for Atmospheric Research
EPA Project Officer: Chung, Serena
Project Period: October 1, 2003 through September 30, 2006 (Extended to September 30, 2007)
Project Period Covered by this Report: October 1, 2003 through September 30, 2004
Project Amount: $440,000
RFA: Measurement, Modeling, and Analysis Methods for Airborne Carbonaceous Fine Particulate Matter (PM2.5) (2003) RFA Text | Recipients Lists
Research Category: Air , Air Quality and Air Toxics , Particulate Matter
Objective:
The objective of this research project is to estimate contributions of biogenic volatile organic compounds (BVOCs), especially monoterpenes and sesquiterpenes, to secondary aerosol production in the eastern United States.
Progress Summary:
The research project includes studies of sesquiterpene emissions; incorporation of biogenic emissions into a new model, the Model of the Emissions of Gases and Aerosol from Nature (MEGAN); development of BVOC emission inventories for base case and future land-use scenarios; and regional-scale air quality modeling using these inventories in the Community Multiscale Air Quality Model (CMAQ). During Year 1 of the project, our work focused on emissions measurements, development of MEGAN and associated land-use databases, and preliminary work with CMAQ.
A literature review on the environmental controls for sesquiterpene emissions from vegetation was compiled, covering the available literature as of spring 2004 (Duhl, et al., 2004). A new field gas chromatography instrument was developed for in-field measurements of BVOC emissions in plant enclosure experiments. This instrument was tested at two field sites (the University of Michigan Biological Station, Michigan, and Duke Forest, North Carolina). Full operation of the instrument is anticipated in January 2005. Two University of Colorado scientists traveled to Duke Forest during September 2004, for an extensive study of the light and temperature dependencies of monoterpene and sesquiterpene emission rates. Approximately 150 emission samples from four enclosure chambers were collected and analyzed. Results from these experiments were presented at the fall 2004 American Geophysical Union Meeting (Herrick, et al., 2004).
MEGAN has been established at a 1-km resolution. The inputs for the model have been based on satellite data, specific vegetation inventories, and the most recent and reliable emission factor and flux measurements. MEGAN recently has been set up to run with the Sparse Matrix Operator Kernel Emissions (SMOKE) Modeling System’s processor, and can be run online with CMAQ. A database of future land cover and land-use data sets and scenarios has been compiled, and selections will be applied to create biogenic emission inventories. An algorithm describing the response of sesquiterpene emissions to light and temperature has been developed using recent measurements.
CMAQ (version 4.4) modeling is being performed with the SAPRC 99 chemical mechanism and AERO3 aerosol module. Emissions and meteorological data for the continental U.S. domain with 36 km x 36 km horizontal resolution, for multiweek episodes in July 2001 and January 2002, were obtained from A.G. Russell at the Georgia Institute of Technology. Model runs have been conducted to compare the default boundary conditions provided by CMAQ with boundary conditions obtained from the Model for OZone And Related chemical Tracers (MOZART) global chemical transport model. Use of the MOZART boundary conditions, which include monoterpenes, resulted in biogenic aerosol concentrations that were up to 50 percent higher at some times and locations than the concentrations obtained with the default boundary conditions.
Future Activities:
We will continue to prepare more enclosure experiments at the National Center for Atmospheric Research greenhouse, to be conducted during January-April 2005. Further measurements on outside vegetation are planned throughout spring and summer of 2005. These experiments will survey a wide variety of vegetation and further characterize the temperature and light dependencies of sesquiterpene emissions. MEGAN emissions of isoprene, monoterpenes, and other VOCs also will be implemented for the model domain of this project in the first part of the year. The model will be run directly with SMOKE. Sesquiterpene emissions will be included in the model during the summer and fall of 2005, based on the results of the laboratory and field measurements. Future land cover data sets will be selected and MEGAN output for each will be produced for the modeling domain. Once the modifications to include sesquiterpene chemistry are completed, CMAQ will be run with existing biogenic emissions data, and the results will be compared to aerosol measurements from networks in the e astern United States. CMAQ runs also will be completed to look at the sensitivity of organic aerosol concentrations to sensitivities in biogenic monoterpene emissions and fire emissions.
Journal Articles:
No journal articles submitted with this report: View all 21 publications for this projectSupplemental Keywords:
biogenic hydrocarbons, secondary organic aerosols, sesquiterpenes, ambient air, terrestrial ecosystems, PM 2.5, air, ecosystem protection/environmental exposure and risk, air pollution effects, analytical chemistry, atmospheric sciences, environmental chemistry, environmental engineering, environmental monitoring, monitoring/modeling, physics, air toxics, particulate matter, PM, volatile organic compounds, VOCs, aerosol analyzers, aerosol particles, air quality model, air sampling, atmospheric particulate matter, biogenic hydrocarbon oxidation, carbon particles, emissions, health effects, measurement methods, particulate matter mass,, RFA, Scientific Discipline, Air, Ecosystem Protection/Environmental Exposure & Risk, particulate matter, air toxics, Environmental Chemistry, Air Pollution Effects, Monitoring/Modeling, Environmental Monitoring, Environmental Engineering, atmospheric particulate matter, health effects, aerosol particles, mass spectrometry, air quality models, air sampling, carbon particles, air quality model, emissions, thermal desorption, particulate matter mass, Volatile Organic Compounds (VOCs), biogenic hydrocarbon oxidation, aerosol analyzersProgress and Final Reports:
Original AbstractThe 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.