[Excerpts from Mar. 9, 2004 USGS Press Release]
Large-scale, long-lasting droughts in the United States – such as the present one in the West -- tend to be linked to warmer than normal sea surface temperatures in the North Atlantic Ocean, and not just cooling in the tropical Pacific, according to a USGS study published today in the Proceedings of the National Academy of Sciences.

The study statistically associates the patterns of U.S. droughts during the last century to multi-decade variations in North Pacific and North Atlantic sea surface temperatures, said USGS lead author Gregory McCabe and his co-authors, USGS scientist Julio Betancourt and Mike Palecki of the Midwestern Regional Climate Center at the Illinois State Water Survey.

In general, McCabe and his coauthors suggest that large-scale droughts in the United States are likely to be associated with positive Atlantic Multidecadal Oscillation (AMO) -- the kind of warming of sea surface temperatures that occurred over the North Atlantic in the 1930s, 50s, and since 1995.

In contrast, wet conditions prevail over most of the country during North Atlantic cooling. The researchers found that cool waters in the central North Pacific are associated with drought in the Northern Rockies and Pacific Northwest, whereas warm waters in the central North Pacific are generally associated with drought in the Southwest and central Plains.

Full Release

[If you come across news of regional interest, please email to asebring@emforum.org or submit via our Feedback Form.]