La Niña Now 20x More Likely to Cause Record Heat Waves Than in 1960s
A new paper, put together by NOAA and the Met Office, looks as the connection between climate change and recent extreme weather events, with some very interesting conclusions.
Let's dispense with the usual bit about how hard it is to link specific extreme weather events solely to the effects of climate change. It's true, but so is the fact that climate change makes these sorts of things more likely. Moving on...
Starting with one very dramatic and devastating event from 2011: The report found that the flooding in Thailand last year was not really related to climate change. The amount of rain received wasn't unusual, even if the extent of flooding was. Rather than climate change, "other factors, such as changes in reservoir policies and increased construction on the flood plain, were found most relevant in setting the scale of the disaster."
So we can move the disaster from natural to, essentially, man-made.
Two extreme weather events that were decidedly not man-made however, that are highlighted by NOAA, are the record-breaking Texas drought and heat of 2011, as well as winter weather weirding in late 2010 and late 2011 in Britain.
Looking at the severity of effects of La Niña, as influenced the Texas drought, the paper finds, "La Niña-related heat waves...are now 20 times more likely to occur during La Niña years today than La Niña years fifty years ago."
As for changing winters in Britain, which experience very cold conditions in December 2010, and very warm weather in November 2011, the report finds, "Cold Decembers are now half as likely to occur now versus 50 years ago, whereas warm Novembers are now 62 times more likely."