"LONDON -- Plants and shrubs have colonised parts of the Arctic tundra in recent decades growing into small trees, a scientific study found, adding the change may lead to an increase in global warming pressures if replicated on a wider scale."

"At 58, retired machinist Bruce Revers is tethered to his oxygen machines -- a wall unit when he’s at home, a portable tank when he’s out. The simple act of walking to the curb to pick up his newspaper is a grind."

Two scientists say BP's aggressive efforts to subpoena e-mails related to their estimate of the oil flow rate during the 2010 Deepwater Horizon Gulf oil spill invade their privacy and threaten the integrity of the scientific deliberative process.

"UNITED NATIONS -- A five-year report out [Thursday] from a U.N. refugee agency goes to great lengths to say climate change is likely to increase human displacement among nations. What is less clear in the report is what can be done about it."

"The White House [Thursday] night issued a veto threat to a pending House spending bill to fund the Department of Energy, the Army Corps of Engineers and other agencies, citing cuts to clean energy promotion and other DOE priorities and 'policy riders' that would reopen the Yucca Mountain nuclear waste depository, undo federal building efficiency requirements and block guidance on the Clean Water Act."

"A federal appeals court [Friday] asked the Department of Energy to explain why it should be able to continue to collect fees for its nuclear waste fund despite the fact that there is no operating national repository."

"LOS ANGELES -- Years of ferocious storms have threatened to gnaw away the western tip of a popular beachfront park two hours drive north of Los Angeles. Instead of building a 500-foot-long wooden defense next to the pier to tame the tide, the latest thinking is to flee."

"MANHATTAN, Kansas -- The site of a proposed facility to fight animal diseases, including those which could be spread by bioterrorists, is little more than a parking lot today because of safety and budget concerns."

"France said it plans to ban a pesticide made by Swiss agro-chemical group Syngenta that is widely used to treat rapeseed crops after scientists suggested it could pose danger to bees."

"A sharp decline in bee populations across the world in recent years, partly due to a phenomenon known as Colony Collapse Disorder, has prompted criticism of pesticide use, although research has yet to show clearly the causes of falling bee numbers.

"The federal government is pushing new efforts to deal with an old problem -- abandoned oil and gas wells. In Pennsylvania, there may be as many as 100,000 orphan wells. If the wells were not sealed properly, they could explode. As The Allegheny Front’s Kate Malongowski reports, the government is using high-tech helicopters to find out where these wells are located."