For years, airlines have offered passengers concerned by climate change an option: For an extra cost, cancel out the carbon dioxide pollution from their share of a flight, by paying to protect trees.

That's the idea behind forest carbon credits. Trees absorb carbon from the atmosphere. Forest carbon credits are promises that companies, individuals and governments can purchase to counteract their emissions by paying to plant or protect trees. Here's a look at this type of carbon credit.

Polar bears in Canada's Western Hudson Bay — on the southern edge of the Arctic — are continuing to die in high numbers, a new government survey of the land carnivore has found. Females and bear cubs are having an especially hard time.

Researchers surveyed Western Hudson Bay — home to Churchill, the town called 'the Polar Bear Capital of the World,' — by air in 2021 and estimated there were 618 bears, compared to the 842 in 2016, when they were last surveyed.

Three lions were shot dead in Sudan after trying to escape from their cages inside a base of Sudan's feared paramilitary forces, an animal shelter official said Thursday.

The Great Lakes have endured a lot the past century, from supersized algae blobs to invasive mussels and bloodsucking sea lamprey that nearly wiped out fish populations.

Now, another danger: They — and other big lakes around the world — might be getting more acidic, which could make them less hospitable for some fish and plants.

Chunks of ice float in milky blue waters. Clouds drift and hide imposing mountaintops. The closer you descend to the surface, the more the water roars — and the louder the "CRACK" of ice, as pieces fall from the arm of Europe's largest glacier.

The landscape is vast, elemental, seemingly far beyond human scale. The whole world, it seems, lies sprawled out before you. Against this outsized backdrop, the plane carrying the man who chases glaciers seems almost like a toy.

A day after negotiators reached a landmark biodiversity agreement, the pressure was already growing on countries, business leaders and the environmental community to deliver on its ambitious promises to protect the planet — and not repeat the failures of past deals.

Delegates expressed optimism Tuesday in Montreal that this time will be different, mostly due to greater financing provisions in the global biodiversity framework and stronger language around reporting, measuring and verifying progress by nations. There is also growing public awareness about threats facing rainforests, oceans and other ecologically important areas.

Climate activists said Wednesday that they have sawed off the tip of the Christmas tree erected in front of Berlin's iconic Brandenburg Gate.

The group Last Generation said two of its members used a hydraulic lift and a hand saw to cut two meters (six feet) off the top of the 15-meter (50-foot) tree and hang up a banner stating: "This is only the tip of the Christmas tree."

At least five people were killed and more than 70,000 rushed to evacuation centers in Malaysia after monsoon-triggered floods inundated the country's north, authorities said Wednesday.

More than 31,000 people have fled their homes in Kelantan state while more than 39,000 residents have been evacuated to temporary shelters in neighboring Terengganu after flooding began over the weekend, the official Bernama news agency said. 

For renewable energy companies in India, it's a good time to be in business.

One of India's largest renewable energy firms, Renew Power, will be among the corporations big and small hoping for a piece of a $2.6 billion government scheme that encourages the domestic manufacturing of components required to produce solar energy. It's the biggest such incentive in India's history.

Tens of thousands of homes and businesses along the Northern California coast remained without power Tuesday evening, nearly a day after a powerful earthquake jolted people awake and shook homes off foundations, injuring at least 12 and leaving many without water.

"It felt like my roof was coming down," Cassondra Stoner said. "The only thing I could think about was, 'Get the freaking kids.'"