Every year, as the holidays approach, global warming hype goes ballistic. This is when the United Nations holds its annual international climate summit, known as "The Conference of the Parties to the Framework Convention on Climate Change", usually (but not always) in some warm place that requires tankers full of jet-A fuel to reach.
My activist-scientist friends don't want to go back to flying in coach, nor do the "Non Governmental Organizations", like Greenpeace and their ilk. So this is also the season when stories of death, destruction, and the end of the world from climate change appear daily. Tens of news items on Google are just a click away.
As a quintessential science example, federal climatologist Ben Santer just published a pal-reviewed paper in the Proceedings of the National Academy of Sciences loudly proclaiming that the dreaded man-made global warming signal has emerged from our naturally chaotic climate.
That's pretty much what he wrote in Nature for the UN's 1996 edition of this conference, 16 years ago. If at first you don't succeed...
Speaking of incessant repetition, U.N. Secretary-General Ban-Ki Moon continues to conflate post-tropical cyclone Sandy with global warming. I guess he thinks that's going to make the U.S. shell out the lion's share of a $100 billion-per-year honeypot that is being demanded by third-world despots, another feature of the U.N's annual climatefests.
Although everyone at the Doha conference can't get enough of poor Sandy, the arguments linking her impressive damages to climate change are less than compelling.
Stories that sea levels have risen dramatically around New York City because of global warming are a bit of a stretch. The continuous record of water level at Battery Park shows a pretty steady rise of about 17 inches since 1856. About half of this was caused by the fact that the land is sinking (as shown in 2009 by S.E. Englehart in Geology). The post-1850 escape from the Little Ice Age of the 17th and 18th centuries is probably good for about a third of the remainder. That leaves a maximum six or seven inches of sea level rise remaining from human-induced warming (probably less), which is pretty small beer.
So, of the 17.34 foot record elevation of the station base sea level caused by Sandy, yes, a maximum of about six inches might be related to human activity. Obviously, if there were no Homo sapiens, Sandy would have caused pretty much the same overwash, with or without warmer seas.
Then there's the notion that global warming pulled Sandy to the west, striking New Jersey, instead of harmlessly recurving northeastward off of Cape Cod. While this was a very popular meme on TV and is no doubt on the lips of all in Doha, it's actually a testable hypothesis.
According to a recent paper by Francis and Vavrus in Geophysical Research Letters, the preferential warming of the Arctic, with a concomitant decline in late-summer sea ice, results in a more meandering jet stream, which is why Sandy shifted westward, rather than being shoved out to sea by the normally strong westerlies associated with the jet.
Satellite data show that arctic late-summer ice has been in decline for about 25 years. The Francis and Vavrus hypothesis predicts that hurricanes will be increasingly deflected westward after they pass Cape Hatteras, instead of taking their usually benign easterly track.
Well, as the Late Casey Stengel would say, "you could look it up". Since 1900, there have been about a dozen (give-or-take one or two because some tracks are a bit ambiguous) that have made landfall in the U.S. north of Hatteras, having acquired a westerly motion component. Some were very destructive, including the 1938 Long Island Express, which would have made Sandy look like a toddler had it made landfall 100 miles farther west. 1972's tropical storm Agnes—which shared a lot of meteorological characteristics with Sandy—produced what is still the flood of record for much of the Northeast.
The last such system was tropical storm Danielle, over twenty years ago. The time between Danielle and Sandy was the longest interval in the record between westward-moving storms north of Hatteras.
So much for that hypothesis. But facts—climatological or familiar—tend not to matter in the holiday season, when climate hype is as common as fruitcake, as our friends in the United Nations party on.