Wherever you are on Earth at 8 p.m. tonight – that’s 8:30 p.m. on your local clock – switch off your lights to participate in Earth Hour 2012.

Earth Hour – a global action movement organized by the World Wide Fund for Nature (WWF) – isheld on the last Saturday of March each year. It began in Sydney, Australia in 2007. Households and businesses are encouraged to turn off non-essential lights for one hour – from 8:30 p.m. to 9:30 p.m. tonight – to raise awareness about the need to take action on climate change. Earth Hour was conceived by WWF and The Sydney Morning Herald in 2007, when 2.2 million residents of Sydney participated by turning off all non-essential lights. Now cities participate in the event.

Earth Hour official website

More about Earth Hour from the World Wide Fund for Nature (WWF)

Sunset Okinawa, Japan via EarthSky Facebook friend Beverly Fish.

Bottom line: Participate in Earth Hour 2012 tonight – March 31, 2012 – by switching off your lights for one hour beginning at 8:30 p.m.

Deborah Byrd

Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.