April 18, 2017
On Feb. 13, 2017, the combined Arctic and Antarctic sea-ice numbers were at their lowest point since satellites began to continuously measure sea ice in 1979.
October 22, 2015
Around the world, from small towns to the biggest cities, civic soldiers in the battle against global warming are striving to cut carbon emissions. One oft-used strategy is to plant more trees, which suck up carbon dioxide, a major greenhouse gas. But does adding more oaks and maples make a dent in urban carbon-reduction goals? How