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Title: A hybrid source apportionment model integrating measured data and air quality model results - article no. D07301

Abstract

The Big Bend Regional Aerosol and Visibility (BRAVO) study was an intensive air quality study designed to understand the causes of haze in Big Bend National Park. Daily speciated fine aerosols were measured from July through October 1999 at 37 sites located mostly in Texas. In support of BRAVO, two chemical transport models (CTMs) were used to apportion particulate sulfate at Big Bend and other sites in Texas to sources in the eastern and western United States, Texas, Mexico, and the Carbon I and II coal-fired power plants, located 225 km southeast of Big Bend in Mexico. Analysis of the CTM source attribution results and comparison to results from receptor models revealed systematic biases. To reduce the multiplicative biases, a hybrid source apportionment model, based on inverse modeling, was developed that adjusted the initial CTM source contributions so the modeled sulfate concentrations optimally fit the measured data, resulting in refined daily source contributions. The method was tested using synthetic data and successfully reduced source attribution biases. The refined sulfate source attribution results reduced the initial eastern U.S. contribution to Big Bend, averaged over the BRAVO study period, from about 40% to about 30%, while Mexico's contribution increased from 24 -more » 32% about 40%. The contribution from the Carbon facility increased from similar to 14% to over 20%. The increase in Mexico's contribution is consistent with more recent SO{sub 2} emissions estimates that indicate that the BRAVO Mexican SO{sub 2} emissions were underestimated. Source attribution results for other monitoring sites in west Texas were similar to results at Big Bend.« less

Authors:
; ; ; ;  [1]
  1. Colorado State University, Ft. Collins, CO (United States)
Publication Date:
OSTI Identifier:
20752218
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Geophysical Research; Journal Volume: 111; Journal Issue: D7
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; 54 ENVIRONMENTAL SCIENCES; AIR QUALITY; USA; POLLUTION SOURCES; AEROSOLS; PARTICULATES; MEXICO; SULFUR DIOXIDE; SULFATES; FOSSIL-FUEL POWER PLANTS; TEXAS; COAL; MATHEMATICAL MODELS

Citation Formats

Schichtel, B.A., Malm, W.C., Gebhart, K.A., Barna, M.G., and Knipping, E.M. A hybrid source apportionment model integrating measured data and air quality model results - article no. D07301. United States: N. p., 2006. Web.
Schichtel, B.A., Malm, W.C., Gebhart, K.A., Barna, M.G., & Knipping, E.M. A hybrid source apportionment model integrating measured data and air quality model results - article no. D07301. United States.
Schichtel, B.A., Malm, W.C., Gebhart, K.A., Barna, M.G., and Knipping, E.M. Tue . "A hybrid source apportionment model integrating measured data and air quality model results - article no. D07301". United States. doi:.
@article{osti_20752218,
title = {A hybrid source apportionment model integrating measured data and air quality model results - article no. D07301},
author = {Schichtel, B.A. and Malm, W.C. and Gebhart, K.A. and Barna, M.G. and Knipping, E.M.},
abstractNote = {The Big Bend Regional Aerosol and Visibility (BRAVO) study was an intensive air quality study designed to understand the causes of haze in Big Bend National Park. Daily speciated fine aerosols were measured from July through October 1999 at 37 sites located mostly in Texas. In support of BRAVO, two chemical transport models (CTMs) were used to apportion particulate sulfate at Big Bend and other sites in Texas to sources in the eastern and western United States, Texas, Mexico, and the Carbon I and II coal-fired power plants, located 225 km southeast of Big Bend in Mexico. Analysis of the CTM source attribution results and comparison to results from receptor models revealed systematic biases. To reduce the multiplicative biases, a hybrid source apportionment model, based on inverse modeling, was developed that adjusted the initial CTM source contributions so the modeled sulfate concentrations optimally fit the measured data, resulting in refined daily source contributions. The method was tested using synthetic data and successfully reduced source attribution biases. The refined sulfate source attribution results reduced the initial eastern U.S. contribution to Big Bend, averaged over the BRAVO study period, from about 40% to about 30%, while Mexico's contribution increased from 24 - 32% about 40%. The contribution from the Carbon facility increased from similar to 14% to over 20%. The increase in Mexico's contribution is consistent with more recent SO{sub 2} emissions estimates that indicate that the BRAVO Mexican SO{sub 2} emissions were underestimated. Source attribution results for other monitoring sites in west Texas were similar to results at Big Bend.},
doi = {},
journal = {Journal of Geophysical Research},
number = D7,
volume = 111,
place = {United States},
year = {Tue Apr 04 00:00:00 EDT 2006},
month = {Tue Apr 04 00:00:00 EDT 2006}
}
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