"A little less than seven years ago, the climate scientist Michael Mann ambled into his office at Penn State University with a wedge of mail tucked under his arm. As he tore into one of the envelopes, which was hand-addressed to him, white powder tumbled from the folds of the letter. Mann recoiled from the grainy plume and rushed to the bathroom to scrub his hands."

"When nearly 200 countries agreed last October to dramatically reduce their reliance on climate change-polluting chemicals called hydrofluorocarbons (HFCs) in air conditioning and refrigeration, the hunt for alternatives was already underway. Now, a new study in the journal Nature Communications that comprehensively explored pure liquid options found only 27 candidates, and problems with all of them."

"President Trump has vowed to roll back regulations on business, and automakers are wasting no time in pushing his administration to make good on the promise."

"Emails released today from U.S. EPA Administrator Scott Pruitt's time as Oklahoma attorney general show he and his office had a familiar if not symbiotic relationship with fossil fuel companies."

"Day after day, Keith Davis stood at the rail of the cargo ship, watching a fleet of rusty long-liners off-load tuna, marlin and other fish."

"As dawn breaks over an encampment that was once home to thousands of people protesting the Dakota Access oil pipeline, a few hundred holdouts rise for another day of resistance."

"President Donald Trump on Tuesday assured ethanol industry advocates of their importance in U.S. energy strategy in an apparent bid to quell concerns over potential changes to policies that mandate the use of such renewable fuels."

"As the nation's 84,000 dams continue to age, a growing number of people downstream are at risk, experts say."

"Leather processing is big business in Bangladesh, India, and other parts of the developing world, where regulations are lax and poisons run freely."

"LOXAHATCHEE NATIONAL WILDLIFE REFUGE, Fla. — Florida water managers are preparing to evict the U.S. Fish and Wildlife Service this summer from a swath of Everglades that it's managed for 66 years."