cropland

Biofuels may increase, not decrease global warming because they result in farmers clearing natural vegetation for crops, according to studies published Thursday in the leading journal Science and reported in the New York Times.

The studies indicate that even biofuels produced on already existing cropland could increase global warming as farmers in other areas clear rainforests and other natural areas to take advantage of a resulting rise in commodity prices.

Of course, biofuels are a renewable, not fossil fuel and may have other non-global warming advantages such as supporting farmers and world peace. The U.S. is unlikely to invade Iowa for its corn.

Scientists are also studying how to some day produce biofuels economically from agricultural bi-products, which would eliminate the land-use impact.