Eco-enthusiastic and anti-fur campaigning singer Leona Lewis has just signed up for Earth Hour 2010 and wants you to join her! On March 27, a “lights out” effort will take place all around the world to advocate energy conservation and spread awareness about climate change.

Earth Hour was actually started by the World Wildlife Fund, whose mission is to conserve wildlife and their natural habitats. This year, Leona’s not the only icon who’s participating— some of the most famous American landmarks are, too! The Empire State Building, the Golden Gate Bridge, and the Las Vegas Strip will all dim their lights (or go completely dark!) at 8:30pm on March 27.

You can join in to support the movement too by spreading the word on your Twitter or Facebook page, organizing a candlelit dinner on the night of the event, and encouraging your friends to switch off their lights!