Palm oil is undeniably attractive to the nations of Southeast Asia that produce it, chiefly Indonesia and Malaysia. As a biofuel, some of it is used in cars and trucks, but most of it winds up in cosmetics and food products like ice cream and chocolates. Demand is high, especially in the West, and it is likely to triple by 2050.

But palm oil has a huge environmental downside, mainly involving deforestation. The clearing of millions of hectares of previously untouched rain forest to make way for palm oil plantations destroys biological diversity and deprives endangered species — among them the rare Sumatran rhino — of their native habitat. It also contributes significantly to global warming.

Scientists have long seen deforestation as an environmental catastrophe. Forests act as sponges to absorb greenhouse gases; destroying forests releases those gases into the atmosphere. The world is losing 12-15 million hectares of forest each year, and this in turn is causing at least 15 percent of global greenhouse gas emissions. Used as a biofuel, palm oil is less carbon intensive than diesel or conventional gasoline, and the E.U., China, India and others are hoping to use more of it in their vehicles. But palm oil’s advantages as a cleaner fuel are clearly outweighed by the deforestation it causes.

Largely because of deforestation, Indonesia is now among the world’s largest emitters of greenhouse gases. It lost one-fifth of its forested area between 1990 and 2010.