"Arctic sea ice, a key indicator of climate change, melted to its lowest level on record this year before beginning its autumnal freeze, researchers at the U.S. National Snow and Ice Data Center said on Wednesday."

"Sea surface temperatures (SSTs) off the East Coast from North Carolina to the Gulf of Maine were the hottest ever recorded for the first six months of 2012, according to NOAA's latest Ecosystem Advisory. Above-average temperatures were found everywhere: from the sea surface to the ocean bottom and out beyond the Gulf Stream."

"BP shut a Norwegian oil and gas field after a potentially dangerous leak, the company said on Tuesday, six days after the incident forced the emergency shutdown of the facility."

"Chlorine has long been the industry standard to keep pool water clean and clear, but consumer demand for alternatives has prompted the emergence of new technologies, including the saltwater systems that came into vogue a few years ago and the copper-and-silver ionization and ozone-gas systems that are increasingly popular."

"The governor declines to declare that one exists. Critics say it's all about business."

"An environmental group asked the U.S. government on Thursday to consider classifying the orange clownfish -- Nemo, to a whole generation of children -- as endangered."

"The Portland City Council voted 5-0 during a raucous public meeting Wednesday morning to add fluoride to Portland's drinking water, ending the city's status as the only major U.S. city that hasn't approved fluoridation."

Oil and gas drilling can usually protect groundwater when enough effort is taken to install well casings and cement them properly. But even those safeguards may fail in karst formations, as the Bureau of Land Management's experience in New Mexico shows.