Absorption of Black Carbon Emitted from Biomass Burning Measured during WE-CAN
Abstract
With the increasing number of wildfires happening in the United States, more properties of wildfire smoke need to be studied, especially the absorption of black carbon (BC), which has a large uncertainty on global radiate forcing. We report the mass absorption cross-section (MAC) of BC (MACBC) by using the airborne measurements taken during the Western Wildfire Experiment: Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE-CAN) campaign in summer, 2018. MACBC at 660 nm is calculated by using absorption coefficients measured by a Photoacoustic Absorption Spectrometer (PAS) and the mass concentration of BC measured by a Single Particle Soot Photometer (SP2). The absorption enhancement at 660 nm is also reported based on the MACBC we calculated. To investigate the evolution of MACBC, the relation between MACBC and physical age, chemical age (O/C ratio and toluene to benzene ratio), modified combustion efficiency (MCE), altitude, and temperature are discussed. An overall MACBC and absorption enhancement at 660 nm are provided for further study on optical properties of BC and in the modification of climate models. Absorption, scattering and SSA at 660 nm are discussed as well, and the fractional absorption from brown carbon (BrC) at 660 nm is calculated, providing an insight into the contribution of the absorption of BC and BrC emitted from biomass burning to the global energy budget.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMA224.0015S
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0325 Evolution of the atmosphere;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0365 Troposphere: composition and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0368 Troposphere: constituent transport and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE