Texas is one of the biggest polluting states in the country—home to oil giants like ExxonMobil and ConocoPhillips. But over the past few years, it's also seen the biggest drop in greenhouse-gas emissions—CO2 output fell some 10 million metric tons between 2004 and 2007, long before the recession took hold. How is that possible? Over in the Wall Street Journal, Ángel González reports:

The reductions are due to lower industrial use of natural gas and a burst of clean-energy development in the state.

Those were the years that Texas became the wind-power leader in the U.S. At the same time, many electricity providers switched from coal to natural gas, which burns a lot cleaner. The report says that on a per-capita basis, emissions from Texas electric generators fell 4% between 2004 and 2007.

I wrote a TNR piece a few years ago on how Texas became the wind-power capital of the United States (oddly enough, then-Governor George W. Bush played a not-insignificant role). But the picture's not totally rosy—it also seems some of the drop has been due to manufacturers packing up and moving the state:

But the biggest reduction came from lower industrial consumption of natural gas, as producers shifted manufacturing to cheaper locations. It’s relatively easy to improve a region’s greenhouse-gas profile when industries move elsewhere. Part of California’s stellar energy-efficiency push is due to its lack of heavy industry, for example.

And China’s greenhouse-gas emissions soared just as it became the world’s workshop. In fact, one thing China will have to do to reduce its carbon intensity and clean up its economy is to reduce the role manufacturing plays in coming decades.

This lends weight to the argument that any cap-and-trade program should also include carbon tariffs, since it doesn't do much good for a state to cut its emissions if the pollution's just getting outsourced to China or elsewhere. Here's an earlier post on the pros and cons of carbon tariffs—and whether they'd make an international climate deal easier or harder. In the Washington Post today, Fred Bergsten and Lori Wallach tried to sketch out a way to tackle carbon tariffs without igniting a global trade war. Worth a read.

(Flickr photo credit: crowt59)