"Protestors rappelled off a bridge and formed a kayak flotilla in Portland, Oregon, on Wednesday hoping to delay Royal Dutch Shell's Arctic oil exploration this summer by blocking the return of a ship to Alaska that holds emergency equipment."

"The company, backed by Elon Musk, think it's figured out how to break open a $10-billion-a-year market."

"Groups opposed to the $5 million ExxonMobil settlement are worried that drinking water for 750,000 Arkansas residents isn't protected."

"A conservation group found 36 U.S. national parks had moderate or worse levels of ozone pollution in a report card released on Tuesday, with four parks in California receiving the worst grades for health effects."

"Fires burning in drought-parched California on Tuesday menaced thousands of structures as firefighters struggled to corral the blazes there and elsewhere in the U.S. West, authorities said."

"The Obama administration has decided to give states more time to comply with proposed regulations that will require dramatic cuts in greenhouse-gas pollution from power plants, people familiar with the plans said Tuesday."

"A U.S. appeals court on Tuesday mostly upheld a major federal environmental regulation requiring some states to limit pollution that contributes to unhealthy air in neighboring states."

"Eleven major environment and conservation groups came out against a Senate energy policy overhaul bill on Monday."

"Republican presidential candidates have generally refused to acknowledge the reality of climate change. New polls and a report issued last week show they aren’t helping themselves with business or voters."