Another eight cities have joined WWF’s 2008 Earth Hour climate change campaign, bringing the tally of international cities up to 24.

Atlanta, San Francisco, Phoenix, Bangkok, Ottawa, Vancouver, Montreal and Dublin will join Sydney, Perth, Melbourne, Canberra, Brisbane, Adelaide, Copenhagen, Aarhus, Aalborg, Odense, Manila, Suva, Chicago, Tel Aviv, Toronto and Christchurch.

WWF is still hoping more cities will get involved.

During Earth Hour last year, 2.2 million Sydney residents turned off lights and appliances for one hour to help reduce the city’s greenhouse gas pollution. With 24 global cities on board for Earth Hour, WWF anticipates that more than 30 million people will be involved this year.

Whether your city has signed up or not, you can get involved. Visit the website and sign up to Earth Hour, plus make sure you switch off lights and non-essential appliances for one hour between 8pm and 9pm on March 29, local time.