Feature

Wind is no longer the energy source of the future. It's ready today.

Until now, rooftop solar has only worked for those with hefty electric bills and sunny roofs.

Searching the Arctic for a long-lost world of woolly mammoths and giant sloths, a traveler discovers a new one disappearing fast

Tribute and terror on skis in Antarctica

Skiing the wild and wildly familiar on Vermont's 300-mile Catamount Trail

Two models for rooftop agriculture vie to feed the Big Apple

A mountaintop-removal coal mine threatens Fayetteville's new outdoor-adventure economy

Rural mothers become solar engineers

Sierra's sixth annual ranking of America's greenest universities

A visitor finds refuge—and tales of deprivation—in the Grand Canyon's hidden alcoves