About 300 people gathered in the City Hall Square in Copenhagen to form the logo of the 350 campaign on the International Day of Climate Action. The campaign is calling for carbon emissions to be cut to 350 parts per million. (Jasper Carlberg / AFP/Getty Images)
Turkish activists in Istanbul carry a large inflatable ball representing Earth during a protest of global warming. (Mustafa Ozer / AFP/Getty Images)
In front of the Brandenburg Gate in Berlin, about 350 demonstrators, some wearing masks of German Chancellor Angela Merkel, demand stronger action in environmental politics. (Caroline Pankert / AFP/Getty Images)
A Turkish child in the center of Istanbul supports the effort with a face painting. The International Day of Climate Action marks 50 days until world leaders meet in Copenhagen to develop a new climate change treaty. (Mustafa Ozer / AFP/Getty Images)
A Ukrainian couple kiss during an ecological rally. The event was one of more than 5,000 in about 180 countries, according to the 350.org website. (Sergey Dolzhenko / EPA)
Environmental activists form a human number “3” along the Jordanian shores of the Dead Sea. (AFP/Getty Images)
Ukrainian women dressed in traditional folk costumes sing folk songs during a global warming protest in Kiev. (Efrem Lukatsky / Associated Press)
At the Opera House in Sydney, Australia, environmental activists create a human “350.” (Tim Cole / EPA)
An aerial view of more than 600 people forming a giant “5” in front of the London Eye -- to link with 3s and 0s formed in other cities. (Lee Slabbert / AFP/Getty Images)
Vietnamese students in Hanoi ride during a bike parade held as part of the global climate action event. (Chitose Suzuki / Associated Press)
Activists in front of La Bourse, the former Stock Exchange building in Paris, hold clocks and cellphones set to ring during a gathering of 11 environmental and human rights organizations. (Francois Mori / Associated Press)
