Lights went off simultaneously Saturday night at about 40 major sites in Yokohama in support of a worldwide movement to generate awareness about global warming.

Landmark Tower, Bay Bridge and Yokohama Red Brick Warehouse were among the structures in the port city that took part in the annual Earth Hour switch-off campaign organized by the World Wildlife Fund.

This year's Earth Hour encouraged people around the world to turn off their lights between 8:30 p.m. and 9:30 p.m. Saturday local time wherever they live, and also pledge to do more to save the planet.

In Yokohama, the U.N.-sponsored Intergovernmental Panel on Climate Change met for five days through Saturday before releasing a key report on global warming on Monday.

More than 20 children wearing costumes of Spider-Man, Earth Hour's ambassador for 2014, led a countdown to the start of the hour.

That was followed by a minute of silence for the areas affected by the massive earthquake and tsunami of March 11, 2011, which left nearly 16,000 people dead and more than 2,600 missing.

"Earth Hour has become something special for Japanese people since we had Earth Hour at the end of March 2011 following the earthquake-tsunami calamity," said Akiko Ishihara, public relations director at WWF Japan.

"This Earth Hour global movement began with an idea by one young Australian, and now we see world famous monuments and some whole towns go dark for an hour," she said.

A total of 150 countries and regions were to take part in this year's Earth Hour, the WWF said.