Atmospheric concentrations of carbon dioxide surpassed a notable milestone this week.

They reached a daily average above 400 parts per million, reported NOAA, for the first time in human history.

The milestone, hit on May 9, may be symbolic, notes Climate Central, but manmade CO2...

Are religious beliefs in the end of the world holding back climate change action in the U.S.?

A study from two researchers at the University of Pittsburgh and the University of Colorado, Boulder found there are "strong reasons" to suggest that widespread belief in "end-times" and a "Second...

The warmest year on record for the continental U.S. also brought the warmest recorded sea surface temperatures in 150 years for the East Coast between Cape Hatteras, N.C. and the Gulf of Maine.

Using satellite and ship-board measurements, NOAA's Northeast Fisheries Science Center (NEFSC) reported that...

Scientists monitoring global atmospheric carbon dioxide concentrations report that, for the first time in human history, CO2 levels could soon rise above 400 parts per million for a sustained period of time in much of the Northern Hemisphere.

Hourly readings have surpassed 400 ppm in...

Climate change means drastic and long-term effects like rising sea levels and the increased likelihood of extreme weather events. But across the world, we are already witnessing the consequences of a warming world.

In the U.S., climate change means that allergies are getting worse...

Along with Earth Day, April 22 marks the final day of the U.S. State Department's 45-day public comment period for the Keystone XL pipeline.

If approved by the State Department, the proposed international pipeline would carry diluted tar sands bitumen nearly 1,200-miles from...

April 22 marks the 43rd observance of Earth Day in the United States. Organized by Sen. Gaylord Nelson (D-Wis.), the first Earth Day in 1970 saw an estimated 20 million Americans demonstrate in support of the environment. By 2012, over one billion people in 192 countries...

Driven by a "fear for this planet's future," actor Ezra Miller has joined with three young people and a support crew on a dramatic expedition to the North Pole.

Miller and the 15 other members of Project Aurora -- organized by Greenpeace as part of their

Following the rupture of Exxon's Pegasus pipeline in Arkansas on March 29, video has emerged of heavy Canadian crude oil flowing through the streets of suburban Little Rock.

As many as 40 homes in Mayflower, Ark., had to be evacuated, KTHV reported. "We could see oil...

Honeybee deaths are on the rise across the world, and researchers are working to find the cause. With as many as 40 or 50 percent of commercial U.S. bee hives lost to colony collapse disorder, according to the New York Times, scientists are eyeing a relatively...

New Jersey Gov. Chris Christie (R) announced Tuesday he has "no sympathy" for property owners who oppose construction of engineered beach dunes in the wake of Superstorm Sandy.

"I'm not going to put up with people who say their view of the Atlantic Ocean is more...

President Barack Obama toured the Argonne National Laboratory outside Chicago on Friday and announced his plans for an "Energy Security Trust" to further clean energy research and development in the U.S.

The trust, which will be funded by federal royalties from offshore oil and gas drilling...

Earlier this week, Senate Budget Committee Chairman Patty Murray (D-Wash.) released a 2014 budget proposal which stands in sharp contrast to the Republican plan offered by Rep. Paul Ryan (R-Wis.).

The Senate Democratic budget -- which has been endorsed by the White House for...

Republican lawmakers pressed President Barack Obama on the Keystone XL pipeline in a meeting on Wednesday. Initial reports suggested Obama would approve the pipeline, but he did not offer a definitive answer.

The New York Times reported the president "indicated" support of the Canadian...

A new special from National Geographic Television and PBS explores the brutal ivory trade and its effect on Africa's elephant populations. "Battle for the Elephants," which airs February 27 on PBS, follows journalists Bryan Christy and Aidan Hartley as they track the ivory trade from Tanzania to China.

An estimated 40,000 people gathered in Washington, D.C. on Sunday for the Forward on Climate Rally on the National Mall. The rally preceded a march to the White House to urge President Barack Obama to take action against climate change and reject the Keystone XL pipeline.

"For the sake of our children and our future, we must do more to combat climate change," President Barack Obama declared in his 2013 State of the Union address. "Yes, it’s true that no single event makes a trend. But the fact is, the 12 hottest years on...

Globally, 2012 was one of the warmest years on record, according to separate reports from NOAA and NASA.

NOAA's 2012 State of the Climate report, released Tuesday, concluded that last year was the 10th warmest since record keeping began in 1880.

According to NOAA, 2012 marked...

At a panel discussion at New York University on December 5, Chelsea Clinton said it was "deeply sobering" that no set of U.S. voters prioritized climate change as a top three voting issue in the 2012 election. With climate change back on the national stage after Superstorm Sandy,...

A "guerrilla" documentary film premiere this week tackled the realities of a changing climate one month after Hurricane Sandy devastated the East Coast.

"Occupy Sandy," which debuted at a surprise outdoor screening above a gas station in Lower Manhattan on Nov. 28, documents the Occupy movement's...