In the case of the 2011 heat wave in Texas, authors of the new U.S.-U.K. research find that adding climate change to La Niña makes scorching heat far more likely.
They reached similar conclusions about unusually warm conditions in central England last November, the second-hottest since record-keeping began in 1659. The scientists say that kind of warmth is 60 times more likely today than it was in the 1960s.
The extreme cold that blanketed the same area in December 2010 is now half as likely to occur now as it was 50 years ago.
But for some natural disasters, including catastrophic floods last year in Thailand, there is no clear connection to man-made climate change.
"We do not see evidence of a human role in all weather extremes," said Peter Stott, climate monitoring and attribution team leader at the U.K. Met Office. "Natural variability is still playing an important role."
In the case of the Thailand floods -- the worst in that country since 1942 -- examination of climate records showed the amount of rainfall that fell was not unusual.
The scientists believe other factors -- like changes in reservoir policies and increased construction in floodplains -- are to blame for the devastating deluge.
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500