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.