Hour when most of the earth went dark

Mikhaylo (St. Michael) Golden Cupolas Cathedral before (top) and during Earth Hour in Kiev March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

India Gate before (top) and during Earth Hour in New Delhi March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

Palace of Culture during (top) and after Earth Hour in Warsaw March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

Hermitage museum during (top) and after Earth Hour in St. Petersburg March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

University embankment during (top) and after Earth Hour in St. Petersburg March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

Ivan Vazov national theatre before (top) and during Earth Hour in Sofia March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

National library before (top) and during Earth Hour in Minsk, March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

"Ham Ca Map" building before (top) and during Earth Hour in Hanoi March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

Leifeng Pagoda before (top) and during Earth Hour in Hangzhou, Zhejiang province March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. Leifeng Pagoda, located at the south of west lake in Hangzhou, was originally constructed in the year AD 975 before the Song dynasty. It collapsed in 1924 but was rebuilt in 2002 as a tourist attraction. (REUTERS)

Marina Bay Sands hotel and ArtScience Museum (R), before (top) and during Earth Hour in Singapore March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 pm local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

Financial district during Earth Hour (bottom) in Shanghai March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

A view of the Badaling section of the Great Wall before (top and middle) and during Earth Hour on the outskirts of Beijing, March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

Petronas Twin Towers in Kuala Lumpur, a Malaysian landmark, pictured as lights are turned off during Earth Hour (top) and turned on after Earth Hour (middle, bottom) March 31, 2012. Landmarks in thousands of cities, from Sydney Harbour Bridge to the world's tallest building, the Burj Khalifa in Dubai, will turn off the power for Earth Hour, the sixth such event promoting a sustainable future for the planet. (REUTERS)

Empire State Building with the lights turned off (L), and with the lights switched back on in participation with Earth Hour, in New York, March 31, 2012. Lights started going off around the world on Saturday in a show of support for renewable energy. (REUTERS)

A volunteer holds up a candle during Earth Hour in Valparaiso city, about 121 km (75 miles) northwest of Santiago, March 31, 2012.  Lights started going off around the world on Saturday in a show of support for renewable energy. (REUTERS)

Athens landmark Acropolis hill with the lights on and with the lights off (bottom-R) during the 'earth hour' on March 31, 2012 in Athens.  Millions of people were expected to switch off their lights for Earth Hour on March 31 in a global effort to raise awareness about climate change that was even to be monitored from space. (AFP)

11th century St. Sofia Cathedral before (L) and during Earth Hour in Kiev March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

97-metre monument Baiterek before (L) and during Earth Hour in Kazakhstan's capital Astana, March 31, 2012. Earth Hour, when everyone around the world is asked to turn off lights for an hour from 8.30 p.m. local time, is meant as a show of support for tougher action to confront climate change. (REUTERS)

Follow Emirates 24|7 on Google News.