Study links California drought to man-made environmental change
By Seth Borenstein ,AP
April 26, 2014, 12:01 am TWN
WASHINGTON -- While researchers have sometimes connected weather extremes to man-made global warming, usually it is not done in real time. Now a study is asserting a link between climate change and both the intensifying California drought and the polar vortex blamed for a harsh winter that mercifully has just ended in many places in the U.S. and Canada.
The Utah State University scientists involved in the study say they hope what they found can help them predict the next big weird winter.
Outside scientists, such as Katharine Hayhoe at Texas Tech University, are calling this study promising but not quite proven as it pushes the boundaries in “one of the hottest topics in climate science today.”
The United States just came out of a two-faced winter — bitter cold and snowy in the Midwest and East, warm and severely dry in the West. The latest U.S. drought monitor says 100 percent of California is in an official drought.
The new study blames an unusual “dipole,” a combination of a strong Western high pressure ridge and deep Great Lakes low pressure trough. That dipole is linked to a recently found precursor to El Nino, the world-weather changing phenomenon. And that precursor itself seems amplified by a build-up of heat-trapping greenhouse gases, the study says.
It's like a complex game of weather dominos that starts with cold water off China and ends with a devastating drought and memorable winter in the United States, said study author Simon Wang, a Utah State University climate scientist.