Intensification of summer rainfall variability in the southeastern United States during recent decades

Journal Article

The variability of summer precipitation in the southeastern United States is examined in this study using 60-yr (1948-2007) rainfall data. The Southeast summer rainfalls exhibited higher interannual variability with more intense summer droughts and anomalous wetness in the recent 30 years (1978-2007) than in the prior 30 years (1948-77). Such intensification of summer rainfall variability was consistent with a decrease of light (0.1-1 mm day-1) and medium (1-10 mm day-1) rainfall events during extremely dry summers and an increase of heavy (.10 mm day-1) rainfall events in extremely wet summers. Changes in rainfall variability were also accompanied by a southward shift of the region of maximum zonal wind variability at the jet stream level in the latter period. The covariability between the Southeast summer precipitation and sea surface temperatures (SSTs) is also analyzed using the singular value decomposition (SVD) method. It is shown that the increase of Southeast summer precipitation variability is primarily associated with a higher SST variability across the equatorial Atlantic and also SST warming in the Atlantic. © 2010 American Meteorological Society.

Full Text

Duke Authors

Cited Authors

  • Wang, H; Fu, R; Kumar, A; Li, W

Published Date

  • 2010

Published In

Volume / Issue

  • 11 / 4

Start / End Page

  • 1007 - 1018

International Standard Serial Number (ISSN)

  • 1525-755X

Digital Object Identifier (DOI)

  • 10.1175/2010JHM1229.1