By marketing to billions of lower-income people, business can do well by doing good: Affordable green goods for “the base of the pyramid” could improve lives and cut environmental damage. Could this work?

California’s fires are a tragedy, but are human actions making them worse? What is the role of global warming and zoning? Can we build safer houses in safer locations?

How do they form? How do we predict their paths? How can we improve predictions?

Greenland’s icecap holds enough water to raise sea level by 7 meters. Some studies show it sliding faster into the sea. Should we worry? New report says “We don’t know.” Comforting?

Global warming gets worse. Petroleum grows scarce. Should we start making biofuels bigtime? If so, should we get the ethanol from corn, or from plant wastes?

Woman is rescued in wilderness after 5-week ordeal. What is so great about wilderness, and why do so many people think they need it to soothe their souls?

Some call it Fall. Some call it spring. But nobody in the Midwest, East Coast or Northern Europe is calling it “winter.” What’s up with our weather?

What would happen to the global climate after a nuclear war between India and Pakistan? Study says the planet would be dark and cool for 10 years. How much would food production decline?

20 years ago, ecotourism was promoted as a way to save natural systems, and the people who lived in them. We ask: Is ecotourism a force for good, or just another form of “greenwashing”?

Measurements show a huge ozone hole. How can this happen? We thought ozone-destroying chemicals were being phased out…