US cut its carbon emissions in 2011 — but China erased the gains - Washington Post (blog)

Yes, it’s true: Americans are slowly starting to tackle global warming. U.S. carbon emissions dropped 1.7 percent last year, according to the International Energy Agency. But that only went so far. Thanks to China’s fast growth, the world’s greenhouse-gas emissions hit record highs in 2011.

Up, up, up. (TIM WIMBORNE - REUTERS) Just how did the United States become so virtuous about its carbon? The IEA offers up three reasons for the emissions decline: First, many U.S. power companies have been swapping out coal for somewhat cleaner natural gas, since the latter has become so cheap. That’s helped a lot. Second, the United States had a mild winter in 2011, which meant less energy was needed for heating. And third, Americans are driving less and purchasing smaller, more efficient cars, which has tempered the country’s oil use.

Still, that hasn’t been enough to stop the relentless rise in global carbon emissions. All told, wealthy countries reduced their emissions 0.6 percent last year. But developing countries saw their emissions grow 6.1 percent. China was the biggest contributor, with carbon dioxide output growing 9.3 percent â€" thanks in large part to a rise in coal consumption. (Now we can see why environmentalists are so leery of having the United States export more of its coal to countries like China.)

As a result, the IEA expects we’re in for a hot future. Remember, leaders from the world’s nations have all pledged to try to prevent global temperatures from rising more than 2 degrees Celsius above pre-industrial levels. Otherwise, the world risks severe droughts, floods, sea-level rises, food shortage, and all sorts of unmanageable nastiness. (Here’s a primer on why many scientists and politicians think 2°C is a good target to shoot for.)

But that goal is increasingly out of reach. “The new data provide further evidence that the door to a 2°C trajectory is about to close,” said IEA Chief Economist Fatih Birol. Instead, says Birol, we’re on a trajectory to heat the planet by about 6°C by the end of the century. For those who prefer Fahrenheit, that’s about 11°F. It’s a big jump. Last year, Birol said that “even schoolchildren know this will have catastrophic implications for all of us.”

But if you don’t want to take the schoolchildren’s word for it, Joe Romm has offered a useful scientific primer on what sorts of dangers 6°C (11°F) worth of global warming could bring. Highlights include “severe drought over 40% of the Earth’s habited landmass by century’s end” and more than a meter of sea-level rise. Here’s the UK Met Office’s projections of where the hot bits will be:

North America gets particularly sweaty. And, according to the Met Office, Washington, D.C., would get downright tropical â€" an extra 13°F or so of heat, on average, by the 2090s. (That's good news for the approximately zero D.C. residents who walk around saying, “What this city needs is an extra 13°F of heat.”)

Now, to be fair, the IEA’s not solely in the business of apocalyptic doomsaying. They also offer solutions. Here’s its earlier report on what the world needs to do to avoid this balmy fate: lots of low-carbon energy, lots of building insulation, lots of efficient vehicles, and so on. A few countries have made modest progress in a few places â€" the U.S. power sector is getting a bit cleaner because of the natural gas boom, and its vehicles are getting more efficient, with new fuel-economy standards â€" but the whole world still has to get on board.