History of the CARG


The Cloud and Aerosol Research Group (CARG) in the Department of Atmospheric Sciences, University of Washington, was founded by Professor Peter V. Hobbs in 1963.

In the early 1960s, the research work of the CARG revolved around laboratory and theoretical studies of cloud processes. In the late 1960s the CARG started to do ground-based field studies of aerosol and clouds, including measurements from a field station near 8000 ft on Mt. Olympus in the Olympic National Park, Washington.

In 1970 the CARG obtained its first research aircraft: a WW-II Douglas B-23, previously owned by Howard Hughes. This aircraft can now be seen, in its original configuration, in the McChord Air Museum, McCord Air Force Base, Tacoma.

Between 1970 and 1984 the CARG flew 3400 hours on the B-23. Data collected on these flights provided the basis for some eighty scientific papers and thirty student theses, on subjects ranging from atmospheric aerosol and cloud chemistry to cloud physics and mesoscale meteorology. Large field projects of note, organized by the CARG, were: the Cascade Project (1970-1974), in which the structures of clouds and the formation of precipitation over the Cascade Mountains, and their modification by cloud seeding, were studied; and, the CYCLES Project (1973-1986) which was concerned with cloud microphysics and the mesoscale organization of rainfall in cyclonic storms in the Pacific Northwest. The demonstration that color display Doppler radars can be used to track mesoscale features was first demonstrated in the CYCLES Project. The B-23 was also used in some of the first airborne studies of volcanic effluents: Mt. Baker (in 1975), several volcanoes in Alaska and, most spectacularly, the major eruption of Mt. St. Helens in 1980.

In 1984 the B-23 was replaced by the considerably larger Convair-131A, which the CARG installed instruments for studying atmospheric aerosols, clouds, atmospheric chemistry and radiation. Studies with the Convair-131A over the next twelve years included the structures of clouds (with emphasis on ice in clouds), the effects of clouds on solar radiation, pollution in the Arctic, the properties of smoke and its effects on climate, the chemistry of the marine atmosphere, and aerosol-cloud interactions. Of particular note were the CARG's studies of smoke from the 1991 Kuwait oil fires, an extensive study of smoke from biomass burning in the Amazon Basin in 1995 (SCAR-B), and studies of cloud structures and the organization of precipitation on the East Coast and in the Central United States. The latter studies led to a new conceptual model for cyclones west of the Rockies. Some other studies with the Convair-131A included MAST, ARMCAS, and TARFOX.

In March 1997 the CARG obtained a Convair-580 aircraft. Within a year of receiving the Convair-580 the CARG had transformed it into one of the best equipped aircraft in the world for measurements of trace gases, atmospheric aerosols and clouds. The Convair-580 was used in the FIRE-ACE/SHEBA field project in Alaska in 1998, the KWAJEX project in the Marshall Islands in 1999, SAFARI-2000 in southern Africa in 2000, IMPROVE-I and IMPROVE-II in the U.S. Pacific Northwest in 2001, and CLAMS on the U.S. East Coast in 2001.

At the end of 2001, the CARG closed down its aircraft program in order to concentrate its efforts on analyses of the large amounts of airborne data it has collected.

Debbie Wolf
Last changed: 2002 November 14