Bill McKibben writes:

In October, 1999, Kerry Emanuel, a professor of atmospheric science at the Massachusetts Institute of Technology, published a paper in the journal Nature that stated, quite baldly: “the evolution of hurricane intensity depends mainly on three factors: the storm’s initial intensity, the thermodynamic state of the atmosphere through which it moves, and the heat exchange with the upper layer of the ocean under the core of the hurricane.” Hurricane Ida followed his script this past weekend—in the course of Saturday night, it moved across very hot water in the Gulf of Mexico and, as a result, strengthened dramatically. By the time it hit the Louisiana coast, it had exploded in intensity, tying for fifth on the list of all-time strongest storms to hit the mainland. In the past seventy years, the United States has averaged three land-falling storms a year; Ida is the seventeenth in the past two years.

Amid the torrent of news reports and Webcam photos and anguished GoFundMe appeals, it’s worth reminding ourselves that this calamity is the predictable result of simple physics. Hurricanes, as Emanuel pointed out, draw their power from heat in the ocean. If there’s more heat, the hurricane can get stronger. Physics. Warm air can hold more water than cold air can. So in warm, arid areas you get more evaporation, and hence more drought, and hence more fire. Physics. The water that’s been evaporated into the atmosphere comes down: more flooding rainfall. Physics. The earth runs on energy. We’re trapping more of it near the planet’s surface because of the carbon dioxide that comes from burning coal and gas and oil. That energy expresses itself in melting ice sheets, in rising seas, in the incomprehensible roar of the wind as a giant storm crashes into a city of steel and glass. It’s not, in the end, all that complicated.

You can’t beat physics. That’s the core fact of the twenty-first century. But you can fight it in two ways, both of which involve politics. The first is to make ready. Ida hit land sixteen years to the day after Katrina did, devastating the region, and since 2005 we have worked together as a nation by, among other things, allocating funds to the Army Corps of Engineers to strengthen the levee system in the metropolitan New Orleans area. So far, the levees have done their job, and the city also has more and better pumps. The Federal Emergency Management Agency is now run professionally—by Deanne Criswell, who used to direct the New York City Emergency Management Department—rather than by somebody who used to run an Arabian horse association.) We have at least a lip-service understanding of who is most vulnerable: poor people and people of color. All of that helps, at least temporarily. (We’ve also obviously got much worse at some things: instead of working together to defeat covid, we have let ideologues derail too much of the vaccination effort, and so the hospitals of New Orleans were already crammed with people on ventilators as the hurricane crashed ashore.) This is not to say that New Orleans is safe: Ida seems to have spared it the worst, but, even so, a major transmission tower that provides some of the city’s power collapsed into the Mississippi. It’s just to say that we can, working together, improve the odds of surviving the inevitable catastrophes.

The second political task is to keep the physics from getting any worse than it has to. That’s a straightforward task: we need to stop burning fossil fuels, because the more carbon dioxide and methane we spew into the atmosphere, the higher the temperature is going to go, and the worse the storms will get. Ida has shut down most of the oil and gas production in the Gulf, for a few days—but production needs to be shut down permanently, as soon as possible. If it isn’t, the physics will just keep getting more impossible. [Continue reading…]