Photo: Jim Watson/AFP/Getty Images
Photo: Joe Klamar/Getty Images
Twilight in Banff National Park
Mist hovers above the frozen Bow River and the Canadian Pacific Railway on Dec. 7, 2013, as twilight falls on Morant's Curve in Banff National Park, Alberta, Canada.
Photo: Chris Wilkins/AFP/Getty Images
The Exxon Valdez spill
An oil-skimming operation works to absorb a heavy oil slick on April 1, 1989, off the coast of Latouche Island, Alaska, just a week after the Exxon Valdez ran aground and spilled 11 million gallons of crude oil into Prince William Sound.
Photo: Saul Loeb/AFP/Getty Images
Actress Daryl Hannah sits in front of the White House in Washington, D.C., on Aug. 30, 2011, to protest the construction of the Keystone XL pipeline.
Hannah was among the dozens of protestors arrested in the demonstration against the oil pipeline which, if constructed, would run from Alberta's oilsands in Canada to Texas.
Photo: Lauro Alves/AFP/Getty Images
Wall of wildfire
A wildfire rages across the Taim Ecological Station in this aerial photo taken on March 27, 2013, in Rio Grande do Sul, Brazil.
Photo: John Mabanglo/AFP/Getty Images
Earth First environmental activists sit atop the stump of an old-growth coast redwood tree that was cut down by a logging company on Sept. 28, 1996, in Headwaters Forest, Calif.
As one of the last remaining unprotected old growth forests in the state, Headwaters Forest was the site of many anti-logging demonstrations and tree-sits until it was finally established as a forest reserve in March 1999.
Photo: David McNew/Getty Images
Supermoon and windmills
A perigee moon, commonly known as a supermoon, rises behind wind turbines on May 5, 2012, near Palm Springs, Calif.
The full moon appears especially large and bright during this once-a-year cosmic event because it's at its closest position to the Earth in its elliptical orbit. The perigee side of its orbit is about 31,000 miles closer to the Earth than the opposite, or apogee, side.
Photo: Daniel Berehulak/Getty Images
A river of wastewater
Indian men bathe in industrial waste foam found on the polluted section of the Yamuna River on May 24, 2013, in the outskirts of New Delhi, India.
As one of India's holy rivers, the Yamuna traverses various urban centers like Delhi, Mathura, and Agra, where fresh water is gathered for daily use and then dumped back into the river as waste.
Photo: Chris Djukanovic/Getty Images
Saving the whales
Protestors stage a demonstration with an inflatable whale on the River Thames at Vauxhall, during a London meeting of the International Whaling Commission in June 1974. In an attempt to stop whaling, the protest group called for support for a Friends of the Earth boycott on Japanese and Russian goods.
Photo: Win McNamee/Getty Images
Bearing the brunt of the BP oil spill
A brown pelican coated in heavy oil wallows in the surf on June 4, 2010, after oil from the Deepwater Horizon incident reached the coast of East Grand Terre Island, La.
Photo: Eric Cabanis/AFP/Getty Images
Flourishing in a field of rubber tires
A stubborn tree grows amidst a field of tires on April 16, 2013, in an abandoned 25-acre recycling yard in Lachapelle-Auzac, France.
Photo: AFP/Getty Images
Dried up waterways
A man strolls along the dry riverbeds of the Hanjiang River on April 9, 2013, in Shiyan, Hubei province, China.
Photo: Stephen Shaver/AFP/Getty Images
A man bicycles down the road on April 21, 1999, as the giant water-cooling towers of a coal-burning energy plant loom above a suburb of Beijing.
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