The causes and effects of the severe Mississippi-Missouri River floods of 1993 will be the focus of the Fall Meeting Union session U11B. This session should interest geophysical scientists in several disciplines, as it examines the meteorological conditions associated with the floods; their magnitudes and extent; the degree to which the floods represent a statistical extreme; and the role of channel constraints, reservoirs, and reservoir operating policies on flood dynamics and resulting damage. Descriptions of several papers to be presented as part of the session are discussed below.
“The Great Midwestern Flood of 1993—A Description and Some Speculation on Causes,” will be presented by Gerald D. Bell, David R. Rodenhuis, and David Miskus of the Climate Analysis Center, Washington, D.C. This paper will examine the persistent circulation pattern that caused a major anomaly in climate conditions covering the upper midwest and north central Great Plains and resulted in the saturation of the Mississippi and lower Missouri rivers. The authors will also investigate hypotheses of global warming, stratospheric aerosols, and El Niño Southern Oscillation as an influence on this weather pattern.