Artists' renderings of New Meadowland show how the wetland would be designed for human recreational use as well as flood control. The berm shown would be a path through the park when water was low (left). When storms came in, the wetlands would flood, and the berm would protect local development. Courtesy of New Meadowlands hide caption

itoggle caption Courtesy of New Meadowlands

President Obama speaks at the U.N. Climate Summit on Tuesday. Discussing America's past, Obama told the group, "We recognize our role in creating this problem." Andrew Burton/Getty Images hide caption

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Demonstrators gather near Columbus Circle before the start of the People's Climate March in New York Sunday. Organizers are hoping 100,000 people worldwide might participate in the rally. Craig Ruttle/AP hide caption

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A Baltimore oriole perches near apple blossoms in Mendota Heights, Minn. Universal Images Group via Getty Images hide caption

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Farmer Seth Watkins (left) and agronomist Matt Liebman stand amid native prairie grasses near Des Moines, Iowa. The conservation strip is used to stop soil erosion. John Ydstie/NPR hide caption

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Doughnuts at a Krispy Kreme store in Washington, D.C. An environmental coalition says leading doughnut companies like Krispy Kreme source palm oil from suppliers who are clear-cutting rain forests and destroying wildlife habitat. Meredith Rizzo/NPR hide caption

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The EPA is proposing rules that would govern carbon dioxide gas emissions by U.S. power plants. Here, coal is transported via conveyor belt to the coal-fired Jim Bridger Power Plant outside Point of the Rocks, Wyo., in March. Jim Urquhart/Reuters /Landov hide caption

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People survey the damage on Scenic Highway in Pensacola, Fla., after part of it collapsed following heavy rains and flash flooding on April 30. Marianna Massey/Getty Images hide caption

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The world must cut its greenhouse gas emissions to meet its goals, climate experts said Sunday. Members of the Intergovernmental Panel on Climate Change (left to right) Youba Sakona, Ramon Pichs Madruga, Ottmar Edenhofer and Rajendra Pachauri hold copies of their new report in Berlin. John MacDougall/AFP/Getty Images hide caption

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