NOAA recently declared this winter to be the 4th warmest on record for the contiguous United States. That sort of announcement might be expected in a warming world. But what about the relatively cold winters of 2009-2010 and 2010-2011, which featured historic blizzards in the Midwest and the East Coast? Florida had snow seven times in 2010! And while we Americans enjoyed a very mild winter this year, Europe endured its most frigid cold snap in decades. That sort of winter weather may seem counter-intuitive in a warming world; it’s the sort of weather columnist Thomas Freidman has in mind when he writes about “Global Weirding.”
NOAA reported today that this winter turned out to be the 4th warmest on record in the contiguous United States. That’s not surprising given how much the world has warmed over the past few decades. In fact, all of the seven warmest years in over 100 years of climate data have occurred since 1992, and over the past three decades, a warmer-than-average winter has been twice as likely as a cool one. These data are consistent with how scientists say global warming affects the weather. The risk of warm winters is increasing over time, but that doesn’t mean that cold winters disappear, similar to the way that loaded dice change the probability of a particular roll but don’t eliminate other possibilities.
A common analogy to explain the link between climate change and extreme weather is gambling with “loaded dice.” For people who aren’t the gambling type but love America’s pastime, perhaps Barry Bonds’ homerun statistics would be more enlightening, or at least more entertaining. A new video from the National Center for Atmospheric Research draws an analogy between a batter on steroids and the “doping” of the atmosphere with manmade CO2.
For the second year in a row, unprecedented numbers of extreme weather events have occurred across the globe. However, more of 2011’s impacts occurred in the United States. From the drought in Texas to the floods in the Midwest and Northeast, this past year underscored the huge economic costs associated with extreme weather. While specific weather events are not solely caused by climate change, the risks of droughts, floods, extreme precipitation events, and heat waves are already climbing as a result of climate change. This year reminded us of our vulnerability to those events.
The Intergovernmental Panel on Climate Change (IPCC) released a “special report” (that’s what they call topical reports they publish in between their better known comprehensive assessments) today that is worth a close look for anyone who wants to start getting ready for a future with weirder and often harsher weather.
About a year ago I published an opinion editorial taking the Intergovernmental Panel on Climate Change (IPCC) to task for neglecting risk-based information to help decision makers cope with inevitable uncertainties about the future impacts of climate change:
Since uncertainty is endemic to the future, when the second IPCC assessment concluded in 1995 that ‘The balance of evidence suggests a discernable human influence on the global climate’, the IPCC should have reconvened around the risk implications of this probable human influence. Instead, it redoubled its effort to reduce physical science uncertainties [which will not be resolved before action is required].