Details

Autor(en) / Beteiligte

• PAN, Z
• SEGAL, M
• TURNER, R
• TAKLE, E

Titel

Model simulation of impacts of transient surface wetness on summer rainfall in the United States Midwest during drought and flood years

Ist Teil von

• Monthly weather review, 1995-05, Vol.123 (5), p.1575-1581

Ort / Verlag

Boston, MA: American Meteorological Society

Erscheinungsjahr

1995

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Surface moisture availability has been hypothesized by various investigators to provide additional negative (positive) feedback on rainfall during summer drought (flood) conditions in the Midwest. In this note, we report on a preliminary numerical modeling effort in which the impact of transient changes in surface wetness on summer rainfall events in the midwestern United States during two recent drought and flood years is assessed. It was found that during the drought of 1988, hypothetical temporary extreme moistening of the surface resulted in large relative increases in simulated rainfall, often by as much as a factor of 2. However, from an agricultural perspective these large relative changes in rainfall might not necessarily have translated into meaningful increases since the original absolute rainfall amounts were quite small. In the flood year of 1993, an assumed transient drying of the surface resulted in relative decreases in simulated rainfall by as much as 30%-40%. This relative decrease in rainfall did, however, translate into a discernible drop in the absolute rainfall.