Picture Gallery: Earth Hour 2012

New York, New York, UNITED STATES : The Empire State Building turns off its lights in this combined image showing before (L) and during (R) Earth Hour, the world wide event to promote conservation of resources, March 31, 2012 in New York. AFP PHOTO

MEXICO CITY, Moco, MEXICO : The Angel de la Independencia monument turns off its lights during Earth Hour, the worldwide event to promote conservation of resources, on March 31, 2012 in Mexico city. AFP PHOTO

Pisa, -, ITALY : This combo of pictures shows the leaning tower of Pisa with the lights on (left) and with the lights off (right) during the Earth Hour, on March 31, 2012, in Pisa. 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 PHOTO

Athens, -, GREECE : This combo of pictures shows the 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 PHOTO

Rome, -, ITALY : This combo of pictures shows St. Peters Basilica with the lights on (top) and with the lights off (bottom) in Rome during the sixth annual Earth Hour on March 31, 2012. 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 PHOTO

Brasa, -, BRAZIL : This combo of pictures shows Brasilias landmark, National Congress (L) and the Esplanade of Ministries with the lights on (top) and with the lights off (bottom) during the sixth annual Earth Hour on March 31, 2012. 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 PHOTO

Brasa, -, BRAZIL : This combo of pictures shows Brasilias landmark, National Congress (L) and the Esplanade of Ministries with the lights on (top) and with the lights off (bottom) during the sixth annual Earth Hour on March 31, 2012. 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 PHOTO

Sao Paulo, S Paulo, BRAZIL : This combo of pictures shows Octavio Frias de Oliveira bridge, over the Pinheiros river, with the lights on (L) and with the lights off (R) during the sixth annual Earth Hour on March 31, 2012 in Sao Paulo. 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 PHOTO

Buenos Aires, Buenos Aires, ARGENTINA : This combo of pictures shows Buenos Aires Piramide de Mayo with the lights on (L) and with the lights off (R) during the annual Earth Hour event on March 31, 2012. 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 PHOTO