Wednesday, April 12, 2017

The U.S. has caused more global warming than any other country.

Also, much of the carbon emission in China come from producing stuff for the U.S. And transporting it a long distance adds to the problem.

By Chris Mooney January 22, 2015


You may have heard that China has recently surpassed the United States in annual greenhouse gas emissions — becoming the largest emitter. That’s true, but it’s a relatively recent occurrence (within the last decade). Looking back over time, the United States is far and away the number one emitter.

This analysis from the World Resources Institute shows that from 1850 to the year 2011, the United States, a single country, produced 27 percent of the total carbon dioxide emissions of the world. No other single country was close — indeed, the U.S. even outdistanced all the nations of the European Union combined:

And the thing about carbon dioxide is, it stays up in the atmosphere for a very, very long time. A recent study by geoscientist Raymond Pierrehumbert of the University of Chicago found that, for a sudden pulse of carbon dioxide in the atmosphere that raises the concentration to 1,250 parts per million over pre-industrial levels (which were about 280 parts per million), about 900 parts per million of carbon dioxide will still be up there after 100 years. Indeed, concentrations will only decline to 675 parts per million over another 900 years.

Thus, much of the carbon pollution emitted over the last 150 or 160 years is very much still with us. It’s still determining our future even today. Which means that for the global warming that the world is currently experiencing and will experience, the United States remains more responsible than any other single country.

And now the comeuppance: In the event of a collapse of the West Antarctic ice sheet, scientists have determined that the United States will receive more sea level rise than almost any other part of the world. (Granted, so will other countries in North America, like Canada and Mexico, which have considerably less global warming responsibility.)


West Antarctica is so large that it pulls the global ocean toward it, which slopes upward toward the ice sheet and the Antarctic continent in general. But if West Antarctica were to lose a substantial part of its ice, then the gravitational pull would relax, and sea level would actually decrease near the ice sheet even as it spreads and increases across the global ocean.

But not evenly. Instead, areas farther from West Antarctica would get more sea level rise, and North America and the United States might get more than any other inhabited place on Earth.


So why does the United States get extra sea level rise? It turns out to be a geophysical “triple whammy,” in Mitrovica’s words.

The first and largest part of the effect is simply gravity. But that’s not the only effect.

In addition, explains Mitrovica, taking a gigantic amount of ice off of the land of West Antarctica leads the crust of the Earth to rebound and thrust upward — pushing the ocean away from it. “That Jack in the Box will be pushing water out of the Antarctic,” says Mitrovica. Some of that pushed water also comes all the way to the northern hemisphere and adds additional sea level rise.

And then, there’s the most mind-boggling effect of all — what Bamber calls “true polar wander.” Basically, moving this massive amount of ice off of West Antarctica also shifts the planet’s axis of rotation slightly. Bamber likens it to how a spinning wheel with gum stuck to it will change its spin somewhat if you stick the gum somewhere closer to the center of the wheel, where the axis of rotation is.

For this reason, says Bamber, “the water sloshes about a little bit in the east-west direction,” and North America gets more of it than Europe does. Triple whammy indeed.


What will never be equitable, though, is this: The U.S. is a rich country. It can pay a lot more to adapt to climate change and to rising sea levels. Poorer countries might get a little less sea level rise in scenarios like the one discussed here — but they’re radically less able to cope with it.

And gravity can’t do anything about that.

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