The artworks precede next week's United Nations climate-policy meeting in Cancun, where negotiators will try to strike a global deal on fossil fuel emissions. Their last attempt, in Copenhagen one year ago, ended in failure.

Since then, the global weather has become even weirder, with extreme events — heat waves in Russia, floods in South Asia, megastorms on the U.S. East Coast — fitting predicted climate-change patterns. In the United States, still the world's major producer of greenhouse gases, a bipartisan climate-change bill failed.

It's easy to become cynical about the situation. But the people filling a dry riverbed in these images and forming other symbolic messages in the other images in this gallery still have hope.

Top: Girl Scouts, church groups and other local citizens in Santa Fe, New Mexico, stand with blue tents and posters in the Santa Fe riverbed./DigitalGlobe and 350.org. Bottom: Don Usner/350.org

Authors: Brandon Keim

to know more click here