If you’re a cycling enthusiast, you’re no doubt aware that Lance Armstrong was recently stripped of all of his Tour de France wins because the U.S. Anti-Doping Agency found evidence of doping. While there are some questions that remain unanswered in the case and there are certainly reasonable criticisms that can be levied against the USADA’s investigation, the scientific evidence appears to be overwhelming.
But I’m not here to talk about Lance Armstrong. Instead, there’s another example where the scientific evidence of doping is overwhelming even though there are a few reasonable criticisms and a few unanswered questions – the doping of Superstorm Sandy by the performance enhancer known as industrial climate disruption (aka global warming or climate change).
Industrial climate disruption increases the amount of heat stored in the Earth’s oceans and atmosphere. When the oceans heat up, they expand, raising sea level. When a warmer ocean and atmosphere melts ice caps (as is happening in Antarctica and Greenland), sea level rises even more. And when sea levels rise, the storm surge that accompanies large storms like Sandy (and Hurricane Katrina) is that much higher than it would have been without
a storm surge .
But there is another effect of industrial climate disruption that doped sea level rise specifically in the region hardest hit by Sandy. The region of the east cost between Cape Hatteras, North Carolina and Boston, Massachusetts appears to be a “hot spot” for local sea level rise that is driven in part by the Atlantic Meridional Overturning Current (AMOC), of which the Gulf Stream is part. When the AMOC speeds up, local sea level drops, and vice-versa. Recently, industrial climate disruption has warmed the air over Greenland enough to significantly increase the amount of freshwater entering the North Atlantic. More fresh water makes the North Atlantic less salty, and thus less dense. Since the AMOC is driven in large part by the warm, salty Gulf Stream cooling and sinking in the North Atlantic, adding lots of fresh water to the Gulf Stream will make it sink slower, and thus slow down the AMOC, leading to sea level rise in the region hit by Sandy that was, according to the paper linked above, 3-4x larger than the global average sea level rise.
There’s a third way that industrial climate disruption enhanced Sandy’s performance, and this is related directly to the warmer oceans. Hurricanes derive their energy from the ocean, and the warmer the ocean is under the storm, the more powerful the hurricane can become. Not all hurricanes become powerful storms over hot water because other factors matter too, but no hurricane can get large and/or powerful without ocean heat. The Atlantic Ocean has become, on average, between 0.9 and 3.6 °F (0.5 to 2 °C) warmer in the area traversed by Sandy over the period from the early 1900′s to the last decade during the months of November and December. This extra ocean heat boosted Sandy’s performance dramatically.
Warmer oceans due to industrial climate disruption also mean more water vapor in the air (over the ocean, anyway), and that means more intense rainfall. And there’s evidence that the dramatic drop in Arctic ice cover changes weather patterns across North America. One of those changes is more common “atmospheric blocking” pattern, which is part of what Sandy fused with to become a superstorm in the first place.
Critics claim that Sandy wasn’t caused by industrial climate disruption. Lance Armstrong’s seven Tour de France wins weren’t caused by his doping, after all. But he was still stripped of his wins because the doping made it much more likely he’d win.
Industrial climate disruption may not have caused Sandy, but it made Sandy more likely and more devastating. And until we stop emitting greenhouse gases like carbon dioxide into the Earth’s atmosphere, industrial climate disruption will continue to dope up hurricanes, droughts, floods, wildfires, and more.