Earth Hour

The metal structure of the greenhouses of the curitiban Botanic Garden (Curitiba, Paraná, Southern Brazil), with its lights off on March 27, 2010.

Earth Hour is an event organized by the World Wide Fund for Nature (WWF). It is held on the last Saturday of March every year. The WWF asks people to shut off their lights and appliances for one hour. They want to raise awareness for climate change. It was started in 2007.

Other websites

• Earth Hour official website