Submitted to: Trans American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: 2/28/2001
Publication Date: 12/10/2001
Citation: Gill, T.E. and J.E. Stout. 2001. Sources and chemistry of atomospheric aerosol in the Souther High Plains of West Texas, USA. Poster presented at: Fall Meeting of the American Geophysical Union, San Francisco, California, December 10-14, 2001. Interpretive Summary:
Technical Abstract: The Southern High Plains (SHP) is an important source of mineral dust aerosols in North America. Dust events in this region have been studied with regard to their climatology and the effect of soil properties on dust production via wind erosion. However, less research has been focused on mineral dust chemistry and the presence of other types of aerosols in the SHP. Aerosol filter samples were collected on a daily basis in various siz fractions (TSP, PM10, and/or PM2.5) at several sites in the region (Lubbock, Reese Center, and/or Big Spring, Texas) since 1996. This unique archive of samples provided the opportunity to better understand the variations in concentration and chemistry of SHP aerosols. A suite of these filter samples was analyzed for their elemental composition by PIXE in a preliminary study of aerosol event types, sites, and size ranges. The results provide chemical profiles of mineral dust within a regionally significant source region, useful for source apportionment studies of particles transported downwind to receptor sites and/or mixed with other aerosol types. Elemental compositions and elemental ratios of SHP dust aerosols in several size ranges generally match those of local sands and carbonate deposits closest to the dust monitoring sites, reflecting wind erosion of local sediments. Iron is enriched in the finer fractions and during the most vigorous wind erosion events, suggesting the abrasion of clay coatings on sands as a mineral aerosol source. The impact of relatively fine smoke aerosols transported long distances from the south in spring 1998 is also documented. Finally, the data illustrate that during infrequent but annual summertime haze events, sulfate aerosols from points east can invade the Southern High Plains.