According to CNN, more than 2,800 cities and towns in 83 countries and 24 time zones dimmed their lights at 8:30pm local time for the third annual Earth Hour. On the U.S. east coast, lights went out at the Capitol dome, Empire State Building, Central Park and George Washington Bridge. Other landmarks include the Pyramids, the Sydney Opera House, the Acropolis, the Eiffel Tower, the dome of St Peter's in the Vatican, Table Mountain in South Africa and the Empire State Building.
Earth Hour kicked off in Oceania; some 23 hours and 45 minutes after the first light switched was turned off on Chatham Island, residents of Honolulu, Hawaii casted their votes against climate change by turning their lights off.
Sydney, Australia, where Earth Hour started just two years ago, was expected to record the highest participation rates on the planet among its population of over 4 million.
Each light that is turned off signifies a vote for action on climate change. Organizers hope that the event will send a message to world leaders meeting in Copenhagen this December.
For more information on Earth Hour, click here. To watch a video clip, click here.