The Atlantic Multidecadal Oscillation went into its warm phase in 1995.
If I'm reading the literature correctly (always ask that question!), the drought in the southwestern U.S. (+PDO; +AMO) should start to relax* and, as the PDO settles in, move to the nations breadbasket (-PDO; +AMO).
Over the next five to twenty years this is going to get really interesting.
Just a little heads-up.
...North American Drought
Drought over north America has been correlated to the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation.
The relationship between drought in the continental US and the phases of the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). The most severe droughts occur when the PDO is in a negative phase, and the AMO is in a positive phase.
From McCabe (2004).
More than half (52%) of the space and time variance in multidecadal drought frequency over the conterminous United States is attributable to the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). An additional 22% of the variance in drought frequency is related to a complex spatial pattern of positive and negative trends in drought occurrence possibly related to increasing Northern Hemisphere temperatures or some other unidirectional climate trend. Recent droughts with broad impacts over the conterminous U.S. (1996, 1999-2002) were associated with North Atlantic warming (positive AMO) and northeastern and tropical Pacific cooling (negative PDO). Much of the long-term predictability of drought frequency may reside in the multidecadal behavior of the North Atlantic Ocean. Should the current positive AMO (warm North Atlantic) conditions persist into the upcoming decade, we suggest two possible drought scenarios that resemble the continental-scale patterns of the 1930s (positive PDO) and 1950s (negative PDO) drought.
—McCabe (2004)
More from Texas A&M.
More from NOAA.
*Wet winter raises water levels, but drought persists
Arizona drought lingers even amid rains
And this could turn out to be old news:
Experts say that the drought in the U.S. could mean climate change
The U.S. Southwest's current drought could be the start of the Dust Bowl-like future that some scientists have already predicted will come from human-caused warming.
Or, it could just be another in the long line of natural, cyclical droughts in the region dating back 1,000 years.
But one of the nation's leading climate scientists, the University of Arizona's Nobel Prize-sharing Jonathan Overpeck, says he's coming to believe there's "a real likelihood" the drought is caused by global warming.
New research at the UA backs that up.
Some other scientists disagree, even as leading climate experts generally agree that someday, global warming will make the Southwest drier.
This drought is already known as the region's worst in more than a century and one of the worst in the past 500 years...
