"The leaders of 25 environmental and climate action groups sent an open letter to President Barack Obama on Tuesday, urging him to reject the proposed Keystone XL pipeline and avoid any 'deal-making' with the Canadian government."

"It would be one of the largest nuclear weapons investments since World War II. A watchdog group says the work -- which may not be needed -- can be done for less elsewhere."

"At its heart, a major new U.S. EPA report that synthesizes more than 1,000 studies about connections among streams, wetlands, rivers and lakes comes down to what elementary school students are taught about the water cycle. Streams flow into creeks that flow into rivers."

"Wild pigs have descended on a suburban Atlanta neighborhood where they are scaring children, making a general nuisance of themselves, and acting as they if they own the place."

"SALEKHARD, Russia -- Russia announced on Tuesday that it had opened a piracy investigation against the crew of a Greenpeace ship after its activists scaled an offshore oil platform in the Arctic last week. The step signaled that the authorities intended to act decisively to thwart more protests against Russia’s ambitious plans to expand energy exploration in the region."

"Tackling climate change would save millions of lives a year by the end of the century purely as a result of the decrease in air pollution, according to a new study."

"The study is published as scientists from around the globe gather in Stockholm to thrash out final details of a landmark assessment of climate science. Their final report is due to be released on Friday 27 September and will set out projections of wide-ranging impacts of global warming from droughts to floods to sea-level rise.

"WASHINGTON — The Obama administration on Friday set the first-ever limits on greenhouse gas emissions from power plants, but their impact could be minimal because they don’t apply to existing plants and there are few coal-fired power plants being built in the United States."

"Airlines on Monday urged a UN aviation group to back a mandatory global framework to curb airline emissions, saying failure to reach a deal would revive threats of a trade war."

"Environmental inspections of oil and gas facilities on public lands have jumped nearly twofold since 2007, but federal investigators said Monday that the government is doing a poor job of targeting the riskiest sites."

"SAN JOSE -- Anticipating a cleanup cost estimated as high as $1.6 billion, local governments from across California made their final legal pitch Monday to hold the paint industry accountable for allegedly threatening children's health by spreading toxic lead paint through tens of thousands of homes."

"A federal judge in New Orleans has handed environmental groups what amounts to half a loaf in their push for federal regulations on the flow of pollutants into the Mississippi River that fuels the annual spring low-oxygen 'Dead Zone' along Louisiana’s Gulf coast."

"Long Island's sole source of drinking water lies beneath many of the most contaminated places in New York State."

"WASHINGTON -- From mercury to pesticides, Americans are exposed daily to environmental chemicals that could harm reproductive health, the nation's largest groups of obstetricians and fertility specialists said Monday."

"New regulations to oversee hydraulic fracturing of oil and gas wells in Alaska could be issued later this year by state regulators, officials said at a public hearing on Monday."

"Germany’s Greens party is open to talking to Chancellor Angela Merkel about joining her third-term government as it seeks to refocus on the switch to clean-energy sources to win over alienated voters."