NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Individual Aerosol Particles from Biomass Burning in Southern AfricaIndividual aerosol particles in smoke plumes from biomass fires and in regional hazes in southern Africa were studied using analytical transmission electron microscopy (TEM), which allowed detailed characterization of carbonaceous particle types in smoke and determination of changes in particle properties and concentrations during smoke aging. Based on composition, morphology, and microstructure, three distinct types of carbonaceous particles were present in the smoke: organic particles with inorganic (K-salt) inclusions, tar ball particles, and soot. The relative number concentrations of organic particles were largest in young smoke, whereas tar balls were dominant in a slightly aged (1 hour) smoke from a smoldering fire. Flaming fires emitted relatively more soot particles than smoldering fires, but soot was a minor constituent of all studied plumes. Further aging caused the accumulation of sulfate on organic and soot particles, as indicated by the large number of internally mixed organic/sulfate and soot/sulfate particles in the regional haze. Externally mixed ammonium sulfate particles dominated in the boundary layer hazes, whereas organic/sulfate particles were the most abundant type in the upper hazes. Apparently, elevated haze layers were more strongly affected by biomass smoke than those within the boundary layer. Based on size distributions and the observed patterns of internal mixing, we hypothesize that organic and soot particles are the cloud-nucleating constituents of biomass smoke aerosols. Sea-salt particles dominated in the samples taken in stratus clouds over the Atlantic Ocean, off the coast of Namibia, whereas a distinct haze layer above the clouds consisted of aged biomass smoke particles.
Document ID
20050176511
Acquisition Source
Headquarters
Document Type
Reprint (Version printed in journal)
Authors
Posfai, Mihaly
(Veszprem Univ. Veszprem, Hungary)
Simonics, Renata
(Veszprem Univ. Veszprem, Hungary)
Li, Jia
(Arizona State Univ. Tempe, AZ, United States)
Hobbs, Peter V.
(Washington Univ. Seattle, WA, United States)
Buseck, Peter R.
(Arizona State Univ. Tempe, AZ, United States)
Date Acquired
August 23, 2013
Publication Date
March 8, 2003
Publication Information
Publication: Journal of Geophysical Research
Volume: 18
Issue: D13
ISSN: 0148-0227
Subject Category
Geophysics
Funding Number(s)
CONTRACT_GRANT: NAG5-9022
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available