By Bradford Plumer Sometime around 2050, there are going to be nine billion people roaming this planet—two billion more than there are today. It's a safe bet that all those folks will want to eat. And that's... an incredibly daunting prospect. Right now, an estimated one billion people go hungry each day.

A new ranking of the world’s nations by environmental performance puts some of the globe’s largest economies far down the list, with the United States sinking to 61st and China to 121st.

The 107 million tons of grain that went to U.S. ethanol distilleries in 2009 was enough to feed 330 million people for one year at average world consumption levels. More than a quarter of the total U.S. grain crop was turned into ethanol to fuel cars last year. With 200 ethanol distilleries in the country set up to transform food into fuel, the amount of grain processed has tripled since 2004.