You know that nearly 4,000 cities and towns in 88 countries went dark, from 8:30 p. m. to 9:30 p. m., time zone by time zone, during "Earth Hour" on Saturday? The message was clear; Earth Hour was a big success; that what the environmental activists expressed on Sunday. The environmental activists certainly did sound pretty happy over the success of the Saturday's "Earth Hour".

The environmental activists stated that now, when "Earth Hour" was a big success, the governments must have a mandate to fight climate change - global warming. The Gland, Switzerland based, World Wildlife Fund (WWF) said, "The world said yes to climate action, now governments must follow."

Started in Australia in 2007 and spread over to 400 cities worldwide in 2008, the "Earth Hour" was dubbed as "the world's first-ever global vote about the future of our planet" by the WWF.

According to WWF, the lights were turned off from Antarctic research base, to the Great Pyramids of Egypt, from the Colosseum in Rome to the Empire State building in New York, to observer Earth Hour. It (Earth Hour) officially started from the Chatham Islands, 500 miles (800 kilometers) east of New Zealand, where diesel generators were switched off. It proceeded to Asia, Europe and crossed the Atlantic to reach North and South America.

Yvo de Boer, top climate official of UN, called the event a clear signal of the world willing to fight global warming. Addressing delegates from 175 nations, de Boer said, "Earth Hour was probably the largest public demonstration on climate change ever. Its aim was to tell every government representative to seal a deal in Copenhagen. The world's concerned citizens have given the negotiations an additional and very clear mandate."

Earth Hour executive director Andy Ridley said, "Earth Hour has always been a positive campaign. It's always around street parties, not street protests, it's the idea of hope, not despair. And I think that's something that's been incredibly important this year because there is so much despair around."