Presentation
The chemical composition of fogs and clouds in the United States
American Geophysical Union 2006 Fall Meeting
(2006)
Abstract
Over the past 15 years we have investigated the chemical and physical properties of fogs and clouds at approximately twenty locations across the United States. Sampling sites have been located in the northeast, southeast, Rocky Mountain, west coast, Pacific Northwest, and Gulf Coast, and in the Pacific (airborne and in Hawaii). They include both pristine and heavily polluted locations. Frontal/orographic clouds (warm and supercooled), coastal and marine stratiform clouds and radiation fogs have all been examined. Measurements at these various locations include "bulk" and/or drop size-resolved cloud drop composition. A variety of single and multi-stage cloud/fog collectors have been developed and used for these studies. Measured species include inorganic ions, organic acids, S(IV), hydrogen peroxide, trace metals, total organic carbon and carbonyls. Observed cloud and fog pH values ranged from below 3 to above 7. Strong variations in composition as a function of drop size are seen at many locations. Because droplet deposition processes depend strongly on drop size, knowledge of drop size-dependent composition is important for understanding fog solute deposition fluxes. This presentation will review sampling approaches and highlight key features of fog and cloud composition and its variation between locations, with time, and as a function of droplet size.
Disciplines
Publication Date
2006
Citation Information
J. L. Collett, A. Bator, H. Chang, B. Demoz, et al.. "The chemical composition of fogs and clouds in the United States" American Geophysical Union 2006 Fall Meeting (2006) Available at: http://works.bepress.com/l-mazzoleni/83/