President Obama (from left), French President Francois Hollande and Microsoft co-founder Bill Gates applaud a speech during the Mission Innovation event at the UN conference on climate change Monday in Paris.
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A building called Sustainability Base, at NASA's Ames Research Center in Mountain View, Calif., has an energy-efficient design that allows in sunlight. So for most of the year, the interior is illuminated by natural light.
A view of the opening of COP21 on climate change Monday in Paris. More than 150 world leaders are meeting for the 21st Session of the Conference of Parties to the United Nations Framework Convention on Climate Change.
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President Obama (center) and Secretary of State John Kerry (right) attend Monday's opening ceremony of the United Nations Climate Change Conference in the Paris suburb of Le Bourget.
After a magnitude-4.5 earthquake was recorded near Cushing in October, Oklahoma regulators ordered oil companies to shut down several disposal wells. That seemed to slow the shaking — at least for a while.
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Delegates from about 170 countries gathered in Kyoto in December 1997 during the United Nations Framework Convention on Climate Change. This year in Paris, the stakes are even higher, negotiators say.
Coal fires burn early in the morning in January 2014 at a privately owned coal mine in India's Jharkand state, making the air dense with noxious smoke and dust. Forty percent of India's mineral wealth lies in Jharkhand.
Gov. Jerry Brown (left) meets with Prime Minister of India Narendra Modi in San Jose, Calif., on Sept. 27. Brown has been brokering his own international agreement on climate change.