As Arctic sea ice melted to the lowest level ever recorded, researchers said they were unprepared for the speed of this facet of climate change. As Arctic ice melts, scientists worry it will add heat and moisture to the globe's climate system.
In pro baseball, which holds its all-star game Tuesday, more than the playing fields are green. Teams are rigorously looking for ways to cut energy use and become better overall environmental stewards.
Since a 2007 Supreme Court decision, the EPA has issued four regulations to curtail carbon emissions. Big industry groups and lawmakers from coal-mining and other energy-producing states have objected.
After rejecting the Keystone XL pipeline proposal in January, President Obama gives a green light to its southern leg – a bid to ease a key bottleneck to new oil supplies and defuse critics on gas prices.
After five years, California has put in place rules to cut greenhouse-gas emissions statewide back to 1990 levels. But lingering effects of the recession have pushed implementation back a year to 2013.
A new study finds that fracking is releasing methane, a greenhouse gas, from a Colorado field at a higher rate than estimates suggested. Researchers must determine if the field is an anomaly or part of a bigger problem.