gina-mccarthy
U.S. Army Corps of Engineers Los Angeles District

Environmental Protection Agency Administrator Gina McCarthy is in China this week for her first international trip as the head of the agency. During her four-day tour she'll stop by Beijing, Shanghai, and Hong Kong and will meet with her counterparts in the Chinese government to discuss how the two countries might reduce their carbon footprint. "The U.S. and China represent the world's largest economies, the world's largest energy consumers, and the world's largest emitters of carbon pollution," McCarthy said last week in a speech previewing her trip. "I'd rather not be the largest energy consumers or the largest emitters of carbon pollution, but since we are we're going to get together and we're going to talk."

The world better hope the planet's two dominant superpowers can find a way to curb their pollution. The U.S., which is responsible for much of the rise in emissions during the 20th century, is certainly one of the world's leading villains when it comes to global warming. But China is now, by far, the world's top producer of climate-destroying pollutants. The country claimed the top spot in global carbon emissions in 2007, nabbing the reins from the U.S. (To be fair to China, the U.S. emits far more carbon per capita.)

Combined, China and the U.S. produce nearly half of the world's carbon emissions. This chart breaks down the percentage of global CO2 emissions from 2008 by country: