skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

This content will become publicly available on April 16, 2020

Title: Optical Properties of Laboratory & Ambient Biomass Burning Aerosols: Elucidating Black, Brown, & Organic Carbon Components & Mixing Regimes

Abstract

Biomass burning (BB) is an important global source of aerosol and trace gases that degrade air quality, decrease visibility, and impact climate and human health. Refractory black carbon (rBC), brown carbon (BrC), and organic aerosol (OA) are major components of BB emissions. BB aerosol composition is highly variable at the source and depends on fuel composition and combustion phase. Atmospheric aging alters fresh BB aerosol through processes that are complex and dynamic. To better understand the variability in optical properties, we report fresh aerosol laboratory measurements from burning southwestern U.S. fuels and compare them to aged ambient BB aerosol from wildfires over a range of atmospheric timescales. Our BB aerosol analysis uses the relationship between the absorption Ångström exponent (AAE) and single scattering albedo (SSA) to identify rBC, BrC, and OA–dominated regimes that are defined using Mie theory. This model framework is used to interpret the large variability in optical properties measured in laboratory burns. In contrast, we find the observed AAE–SSA relationship for ambient BB aerosol to be less variable and more clustered together with increased atmospheric aging. This transition from fresh to aged behavior is attributed to the homogenization of the BB aerosol from mixing and aging overmore » several hours. As a result, BB aerosol in ambient fire plumes that have aged for several hours exhibit larger SSAs than laboratory flaming burns. We conclude that BrC/OC mixtures play a larger role than rBC in the positive climate forcing of BB aerosol than what would be projected from laboratory results.« less

Authors:
ORCiD logo [1];  [2];  [3];  [3]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); New Mexico Inst. of Mining and Technology, Socorro, NM (United States)
  3. New Mexico Inst. of Mining and Technology, Socorro, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1508557
Alternate Identifier(s):
OSTI ID: 1511059
Report Number(s):
LA-UR-18-30035
Journal ID: ISSN 2169-897X
Grant/Contract Number:  
89233218CNA000001; F265; DE‐AC52‐06NA25396
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Geophysical Research: Atmospheres
Additional Journal Information:
Journal Name: Journal of Geophysical Research: Atmospheres; Journal ID: ISSN 2169-897X
Publisher:
American Geophysical Union
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; 54 ENVIRONMENTAL SCIENCES; Earth Sciences

Citation Formats

Romonosky, Dian E., Gomez, Samantha L., Lam, Jared Tate, Carrico, Christian M., Aiken, Allison C., Chylek, Petr, and Dubey, Manvendra Krishna. Optical Properties of Laboratory & Ambient Biomass Burning Aerosols: Elucidating Black, Brown, & Organic Carbon Components & Mixing Regimes. United States: N. p., 2019. Web. doi:10.1029/2018JD029892.
Romonosky, Dian E., Gomez, Samantha L., Lam, Jared Tate, Carrico, Christian M., Aiken, Allison C., Chylek, Petr, & Dubey, Manvendra Krishna. Optical Properties of Laboratory & Ambient Biomass Burning Aerosols: Elucidating Black, Brown, & Organic Carbon Components & Mixing Regimes. United States. doi:10.1029/2018JD029892.
Romonosky, Dian E., Gomez, Samantha L., Lam, Jared Tate, Carrico, Christian M., Aiken, Allison C., Chylek, Petr, and Dubey, Manvendra Krishna. Tue . "Optical Properties of Laboratory & Ambient Biomass Burning Aerosols: Elucidating Black, Brown, & Organic Carbon Components & Mixing Regimes". United States. doi:10.1029/2018JD029892.
@article{osti_1508557,
title = {Optical Properties of Laboratory & Ambient Biomass Burning Aerosols: Elucidating Black, Brown, & Organic Carbon Components & Mixing Regimes},
author = {Romonosky, Dian E. and Gomez, Samantha L. and Lam, Jared Tate and Carrico, Christian M. and Aiken, Allison C. and Chylek, Petr and Dubey, Manvendra Krishna},
abstractNote = {Biomass burning (BB) is an important global source of aerosol and trace gases that degrade air quality, decrease visibility, and impact climate and human health. Refractory black carbon (rBC), brown carbon (BrC), and organic aerosol (OA) are major components of BB emissions. BB aerosol composition is highly variable at the source and depends on fuel composition and combustion phase. Atmospheric aging alters fresh BB aerosol through processes that are complex and dynamic. To better understand the variability in optical properties, we report fresh aerosol laboratory measurements from burning southwestern U.S. fuels and compare them to aged ambient BB aerosol from wildfires over a range of atmospheric timescales. Our BB aerosol analysis uses the relationship between the absorption Ångström exponent (AAE) and single scattering albedo (SSA) to identify rBC, BrC, and OA–dominated regimes that are defined using Mie theory. This model framework is used to interpret the large variability in optical properties measured in laboratory burns. In contrast, we find the observed AAE–SSA relationship for ambient BB aerosol to be less variable and more clustered together with increased atmospheric aging. This transition from fresh to aged behavior is attributed to the homogenization of the BB aerosol from mixing and aging over several hours. As a result, BB aerosol in ambient fire plumes that have aged for several hours exhibit larger SSAs than laboratory flaming burns. We conclude that BrC/OC mixtures play a larger role than rBC in the positive climate forcing of BB aerosol than what would be projected from laboratory results.},
doi = {10.1029/2018JD029892},
journal = {Journal of Geophysical Research: Atmospheres},
number = ,
volume = ,
place = {United States},
year = {2019},
month = {4}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on April 16, 2020
Publisher's Version of Record

Save / Share: