The Food and Drug Administration says it is reviewing whether the maker of the most widely used emergency contraceptive pill needs to change its label in light of new evidence that it doesn't work to prevent pregnancy in overweight or obese women.
The United Nations negotiations in Warsaw over a climate treaty are moving at glacial speed — and that's in part because there's a fundamental problem.
In the coming decades, carbon dioxide emissions from China, India and other rapidly developing countries are expected to grow quickly. Residents there aspire to lifestyles Americans and Europeans enjoy today, and those nations aren't willing to slash emissions, because doing so could slow their economic growth.
Methane is the source of the gas we burn in stoves. You can also use it to make plastics, antifreeze or fertilizer. It comes out of underground deposits, but it also seeps up from swamps, landfills, even the stomachs of cows.
And while methane is valuable, a lot of it gets up into the atmosphere, where it becomes a very damaging greenhouse gas.