DETERMINATION OF THE SOURCES OF CARBONACEOUS ARCTIC AEROSOLS. Steven
R. Biegalski, NIST, Chemistry, Room B162, Gaithersburg, MD 20899, phone:
301-975-3138, fax: 301-216-1134, e-mail: steven.biegalski@nist.gov)
Both natural and anthropogenic combustion processes result in the introduction
of aerosol particles to the atmosphere. These combustion aerosols have the
potential to greatly affect human health, visibility, and global change.
It is necessary to study the anthropogenic components of the atmosphere
so that they may be delineated from the natural components, and so that
their sources may be determined. Reliable scientific data on anthropogenic
emissions are crucial for the institution of applicable policies and the
regulation of man-made emissions. Recent work at the National Institute
of Standards and Technology (NIST) has focused on the analysis of carbonaceous
particles found in the Arctic aerosol, snow, and ice. Goals of the work
include measurements of elemental carbon, organic carbon, total carbon,
12C, 13C, 14C, and other properties of
the particles which may aid in identification of their respective sources.
The very low particulate concentrations in the Arctic make these measurements a challenge. The measurement of the carbon concentrations utilize a suite of analytical methods. Total carbon determinations are made via coulometry, manometry, and with a CHN analyzer. In order to separately determine organic from elemental carbon, pre-analysis steps have been investigated which separate organic from elemental carbon. Accelerator mass spectrometry (AMS) is used for the determination of carbon isotopes.