In this June 1, 2015 file photo, a discarded sofa litters the shore of Guanabara Bay in Rio de Janeiro, Brazil. The sailing regatta at the Rio de Janeiro Olympics will be both filthy and photogenic. The troubled waters of Guanabara Bay have made news for the wrong reasons, with an independent study by The Associated Press showing high levels of viruses and sometimes bacteria from human sewage. There have also been unsightly buildups of trash. (AP Photo/Silvia Izquierdo, File)...

Floridians and residents of other coastal communities beware: There are changes afoot on one of Earth's largest ice sheets that could accelerate global sea level rise. Two new studies on Greenland's melting ice sheet are redefining previous scientific models and research on the topic, suggesting that the ice sheet, capable of raising sea levels by more than 20 feet if it melted entirely, could melt faster than previously thought. And as NASA says, if Greenland's ice sheet were to melt...

Greenpeace activists ignited controversy in Peru after they reportedly damaged a more than 1,000-year-old sacred cultural site during a protest earlier this week. A dozen or so Greenpeace activists, shrouded in the darkness of night, hiked more than a mile through the Peruvian desert and into an off-limits area Monday to place large yellow letters that read "Time For Change! The Future is Renewable" (referencing renewable energy) next to the famed hummingbird geoglyph at the Nazca Lines. The Nazca Lines...