The skies were brightening over Philadelphia on the way into Center City this afternoon, as Hurricane Sandy skedaddled for parts north. It was a bad storm here but a once-in-a-life nightmare along the Jersey Shore and parts of New York City. We're still mourning the loss of at least 30 souls in the hurricane, a number that's certain to rise. But as the immediate shock wears off, the conversation is certain to turn to the tangentials, including the storm's impact on Tuesday's (hopefully) presidential election, and -- loosely related -- the "debate" over climate change.
At a time when we're worried about a warming planet -- and the role that human activity causes in that warming -- leading to more extreme weather, it doesn't get more extreme than Sandy, the icy-hot-patch of Atlantic storms, merging warm tropical air into a chilly fall blast of Arctic air to create a Halloween monster with 90 mph winds, record storm surges at sea level and blizzards in the mountains, extending over 1.000 miles.
But did climate change cause Sandy? That's doubtful. No one but most ill-informed has argued that global warming actually causes hurricanes, although it tends to make most tropical storms more powerful. But you just can't project very well onto any one particular storm. No one would blame the Long Island Express of 1938 on greenhouse gases.
As noted here:
The science of climate attribution is very exciting and full of cool, new ideas. It has already provided us with first steps towards more precision in understanding how climate change is changing climate now, already. For hurricanes, however, sticking to the science means it is still hard to point to an individual storm and say, yes! Climate change! A more reasoned approach is to take the full weight of our understanding about the Earth and its systems and go beyond asking if any particular event is due to global warming or natural variability. As Kevin Ternbeth of NCAR says "Nowadays, there's always an element of both."
Point well taken. But there was one unusual aspect of Sandy that troubled me -- from a climate change perspective -- as I watched the hurricane chug up the Eastern Seaboard. This far into autumn, a tropical storm ought to lose strength over the north Atlantic. Instead it was alarming to see Sandy's sustained win rise from 75 mph to 90 mph and its central pressure drop -- undoubtedly due in part to the fact that the Atlantic waters are so much warming than average right now. And many scientists believe human activity is to blame for some of that rise in the surface water temperature,
Andy Revkin of the New York Times, one of the best environmental writers on the planet, emailed a bunch of experts about Sandy and received an interesting array of responses. Here is what Jennifer Francis of Rutgers told him:
The jet stream pattern — particularly the strongly negative NAO [North Atlantic Oscillation] and associated blocking — that has been in place for the last 2 weeks and is projected to be with us into next week is exactly the sort of highly amplified (i.e., wavy) pattern that I’d expect to see more of in response to ice loss and enhanced Arctic warming. Blocking happens naturally, of course, but it’s very possible that this block may have been boosted in intensity and/or duration by the record-breaking ice loss this summer. Late-season hurricanes are not unheard of either, but Sandy just happened to come along during this anomalous jet-stream pattern, as well as during an autumn with record-breaking warm sea-surface temperatures off the US east coast. It could very well be that general warming along with high sea-surface temperatures have lengthened the tropical storm season, making it more likely that a Sandy could form, travel so far north, and have an opportunity to interact with a deep jet-stream trough associated with the strong block, which is steering it westward into the mid-Atlantic. While it’s impossible to say how this scenario might have unfolded if sea-ice had been as extensive as it was in the 1980s, the situation at hand is completely consistent with what I’d expect to see happen more often as a result of unabated warming and especially the amplification of that warming in the Arctic.
That makes sense to me, but I also agree with Revkin's broader theme here, which is the climate change issue is debatable.
That brings me to my more important point, which I've mentioned on this blog in the past, but screams out louder today than any time in the last year. We didn't need to wait for a killer storm to slam into New Jersey to begin having a conversation about climate change. We've already had the ideal moment for debate, the election of a U.S. president who will serve for the next four years.
And yet both President Obama and Mitt Romney have their own politically minded -- and narrow-minded -- reasons for never bringing the issue up. Even more appalling, neither did the moderators chosen by the Commission on Presidential Debates. We know a little -- that Obama pays lip service to climate change and Romney shifts with the political winds -- but there's no sense of what, if anything, either presidential wannabe would do in the critical years from 2013 through January of 2017.
And that's a disgrace. And, to answer the question posed in the headline, it's definitely not too early to discuss Sandy and global warming.
The only question that matters is...is it too late?