SP-AMS Measurements of Black Carbon Containing Particles during the FLAME3 Smoke Chamber Study

EDWARD FORTNER (1), Achim Trimborn (1), Timothy Onasch (1), Gavin McMeeking (2), Taehyoung Lee (3), Hugh Coe (2), Jeff Collett (3), Sonia Kreidenweis (3), Cyle Wold (4), Wei Min Hao (4), John Jayne (1), Doug Worsnop (1)

(1) Aerodyne Research Incorporated, Billerica MA USA (2) University of Manchester, Manchester England (3) Colorado State University, Ft. Collins CO USA (4) United States Forest Service Fire Sciences Laboratory, Missoula, MT USA

     Abstract Number: 616
     Last modified: May 14, 2010

Abstract
Black carbon containing aerosols are considered to have a major impact on climate change and an improved characterization of the chemical composition of black carbon containing particles will help to elucidate black carbons role in climate and visibility. During the Fire lab at Missoula experiment (FLAME 3) intensive study in September 2009 the soot particle aerosol mass spectrometer (SP-AMS) instrument developed by Aerodyne Research Incorporated (ARI) conducted smoke chamber measurements of a variety of biomass burning species. The SP-AMS instrument combines the ability to measure black carbon featured by the single particle soot photometer (SP2) (Droplet Measurement Technologies, Boulder, CO) with the ability to determine the chemical composition of the coatings surrounding these black carbon cores. A 1064 nano-meter laser is used to heat particles rather than the conventional method of impaction on a heater.

A number of different biomass species were burned during FLAME3 each producing varying ratios of small to large carbon clusters. We examine the relationship of predominant carbon cluster size with the type of biomass burned as well as the absorption and optical properties of the black carbon. The mass ratio of the black carbon cores to coatings on the particles varied substantially with different fuels. A SP2 and photoacoustic light absorption spectrometer operated by the University of Manchester sampled alongside the SP-AMS and a thermal denuder system was operated upstream of the three instruments. The volatility of the coatings present on the black carbon particles is compared to the volatility of coatings measured with a conventional HR-ToF AMS operated by Colorado State University. The concentration of organics measured with the HR-ToF AMS is compared with the concentration of organics measured with the SP-AMS giving insight into the ratio of black carbon particles to total particles for various fuels.