World landmarks dimmed for Earth Hour
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Credit: Getty Images
SYDNEY, AUSTRALIA - MARCH 30: The Opera House is seen before the lights are switched off for Earth Hour on March 30, 2012 in Sydney, Australia. Earth Hour encourages individuals around the world to turn off their lights for one hour at 20:30 local time on March 31, 2012 to take a stand against climate change. (Photo by Lisa Maree Williams/Getty Images)
