Interplay Between Black and Brown Carbon from Biomass Burning and Climate

EPA Grant Number: R835883
Title: Interplay Between Black and Brown Carbon from Biomass Burning and Climate
Investigators: Murphy, Shane Michael
Institution: University of Wyoming
EPA Project Officer: Chung, Serena
Project Period: January 1, 2016 through December 31, 2018 (Extended to December 31, 2019)
Project Amount: $349,847
RFA: Particulate Matter and Related Pollutants in a Changing World (2014) RFA Text |  Recipients Lists
Research Category: Air , Climate Change


  1. Observe the wavelength-resolved single scattering albedo (SSA) of aerosol biomass burning emissions in the Western United States.
  2. Determine the contribution of black versus brown carbon to observed aerosol absorption.
  3. Quantify the enhancement of black carbon absorption caused by organic coatings.
  4. Update the refractive indices of organic and black carbon aerosol from biomass burning in the NCAR Community Atmosphere Model (CAM5) with data obtained from in-situ measurements.
  5. Assess the regional and global climate impacts of improved optical properties under a range of future biomass burning scenarios.
  6. Investigate the current and future radiative forcing and climatic effect from brown carbon absorption utilizing CAM5.


A unique suite of instrumentation will be installed in the University of Wyoming mobile laboratory and deployed to active fires in the Western U.S. during the fire seasons of 2015 and 2016.  Data from the deployed instruments will allow calculation of highly-uncertain optical properties for biomass burning aerosol, namely: SSA, absorption enhancement, and the refractive index of raw black carbon cores and organic coatings at 660 and 405 nm.  Optical properties of biomass burning aerosol in the modal aerosol model (MAM) within NCAR’s Community Atmosphere Model (CAM5) will be updated with collected data and the impact of improved biomass burning aerosol optical properties will be evaluated under current and future biomass burning scenarios.

Expected Results:

This study will result in significantly improved understanding of the impact of aerosol from biomass burning on regional and global climate.  It focuses on fires in the Western U.S., but results will be informative for other regions.  It will clarify the relative importance of black versus brown carbon to aerosol absorption from biomass burning.  CAM5 model runs with newly acquired optical properties will allow assessment of the potential regional and global climate impact Western U.S. biomass burning.

Publications and Presentations:

Publications have been submitted on this project: View all 2 publications for this project

Supplemental Keywords:

Air, Tropospheric, Atmosphere, Climate Models;

Progress and Final Reports:

  • 2016 Progress Report
  • 2017 Progress Report
  • 2018