"A possible amendment from Sen. Lisa Murkowski (R-Alaska) has the potential to handcuff U.S. EPA from exercising its full regulatory power [over greenhouse gases], a scenario that has sent shockwaves through the environmental community."

"The Environmental Protection Agency said on Tuesday that it would require the nation’s biggest emitters of greenhouse gases to start tracking their emission levels on Jan. 1 and report them to the government."

"China laid out a plan to curb carbon emissions by 2020 and U.S. President Barack Obama called on all nations to act now to tackle global warming, as world leaders tried to inject momentum into climate change talks."

"A two-judge panel of a federal appeals court has ruled that big power companies can be sued by states and land trusts for emitting carbon dioxide. The decision, issued Monday, overturns a 2005 District Court decision that the question was political, not judicial."

"The world leaders who are meeting at the United Nations to discuss climate change on Tuesday, are faced with an intricate challenge: building momentum for an international climate treaty at a time when global temperatures have been stable for a decade and may even drop in the next few years."

"On Tuesday, the U.N. is holding a day-long Climate Summit (alongside its annual, two-week General Assembly) in New York City. And on Thursday and Friday, the Group of 20 (G20) leading world economies is gathering in Pittsburgh, its third meeting of the year to deal with the global economic meltdown."

"U.S. EPA is poised to establish a national registry for heat-trapping emissions after the White House [Sept. 16] completed its review of the agency's final greenhouse gas reporting rule."

Scientists use treetop gondolas in the Gifford Pinchot National Forest in southeast Washington to study the effects of global warming on trees.

"Dakota, Minnesota & Eastern Railroad this summer started to walk away from its rail expansion project in the Powder River Basin, the largest source of coal in the country, citing the flagging U.S. economy and regulatory uncertainty."