carbon dioxide

There is one number that the Environmental Protection Agency relies on to decide which climate policies to pursue. So why does that number assume the lives of richer people are worth more?

Researchers at Oxfam, a nonprofit devoted to combating poverty, examined billionaires who collectively own $2.4 trillion in company equity, with investments across 183 companies.

Building and operating telescopes can generate a lot of greenhouse gases. In fact, it's as if each astronomer in the world was driving more than 100,000 miles per year, a new study finds.

Cutting carbon emissions to zero in the next 30 years would save about 74 million lives this century, a new analysis estimates.

The U.S. is planning to rapidly reduce greenhouse gas emissions. This is America's return to the international climate stage. We break it down for you.

The U.S. plans to reduce greenhouse gas emissions dramatically in the next decade. Scientists say it's crucial that the U.S. succeed. Still, many of the positive effects won't arrive for decades.

The global slowdown could create a historic drop in carbon emissions, but it's still not enough to avoid the worst impacts of climate change.

In the search for alternatives to coal and gas, some European countries have turned to a very old fuel. They're importing wood from the United States. Some environmentalists say it makes no sense.