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.
Although droughts remain largely unpredictable, McCabe suggests that “this research, as well as that of others, “increases concern that the current drought in the West could persist due to continuing above normal North Atlantic sea surface temperatures.” The focal region of the drought may shift with the more variable North Pacific sea surface temperatures, he said.
