What makes Earth Day special and why we still need it

The Earth Day Network coordinates activities that raise awareness of local environmental issues, as well as global climate change, in 192 countries.

U.S. homebuilders are capturing the sun

More than half a million U.S. homes and businesses have gone solar. Lower installation costs and growing government incentives have made it easier and...
Aerial view of group of people planting shrubs (© Getty Images)

Cities as policy labs: Chicago’s rooftop experiment

Chicago's rooftop gardens reuse water and reduce heat, which can reduce a building's power costs. The city has 418,000 square meters of high-rise greenery.
Giant clam (AP Images)

This clam can change the future of energy

Could the giant clam's colorful lips hold the key to renewable energy? At 200 kilograms, and with life spans exceeding a century, these magnificent...

Climate change is changing how we act

As part of the effort to fight global climate change, the White House has identified 16 U.S. cities cutting carbon pollution through everyday acts. Cities such as...

Cities as policy labs: L.A. cleans up its smog

With the largest fleet of natural gas buses in the U.S. — about 2,200 — Los Angeles has become a leader in cutting carbon emissions.

Need strategies to clear the air? Ask a megacity.

Big cities have big problems with pollution and are big laboratories for solutions. C40 Cities helps them collaborate on strategies.

Melting away

“Ice is alive in some strange kind of way," says James Balog, who has chronicled the disappearance of glaciers through the Extreme Ice Survey since...
Person riding bike with city skyline in background (© AP Images)

Cities as policy labs: Portland’s bicycle experiment

With bicycle boulevards, 'sharrows' and more than 500 kilometers of bikeways, Portland, Oregon, has become one of the greenest cities in the U.S.