The number of monarch butterflies wintering in the mountains of central Mexico dropped 22% from the previous year, and the number of trees lost from their favored wintering grounds tripled.

Frost and "extreme temperatures" in the United States may have played a role in the butterfly's decline during the most recent winter season, said Humberto Peña, director of Mexico's nature reserves.

It's one of the world's most vital resources. In Paraguay, a man displaced by a rising river hauls heavy buckets of it to his temporary home. In the Philippines, a girl uses a manual pump to get just enough to wash. In Haiti children fill large jugs of it in dwindling ravines.

Water is the lifeblood of every community around the world. But a sustainable, clean supply for drinking, hygiene and farming is not guaranteed for hundreds of millions of people, according to United Nations figures.

A report issued on the eve of the first major U.N. conference on water in over 45 years says 26% of the world's population doesn't have access to safe drinking water and 46% lacks access to basic sanitation.

The U.N. World Water Development Report 2023, released Tuesday, painted a stark picture of the huge gap that needs to be filled to meet U.N. goals to ensure all people have access to clean water and sanitation by 2030.

A 5,000-mile seaweed belt lurking in the Atlantic Ocean is expected in the next few months to wash onto beaches in the Caribbean Sea, South Florida, and the Yucatán Peninsula in Mexico.

The Great Atlantic Sargassum Belt — as the biomass stretching from West Africa to the Gulf of Mexico is called — contains scattered patches of seaweed on the open sea, rather than one continuous blob of sargassum. It's not a new occurrence, but satellite images captured in February showed an earlier start than usual for such a large accumulation in the open ocean.

Snow falls thick as skiers shed their gear and duck into the Sundeck Restaurant, one of the first certified energy efficient buildings in the U.S. – this one at 11,200 feet (3,413 meters) above sea level atop Aspen Mountain in Colorado. Skiers in brightly colored helmets jockey for a spot at the bar, their bodies warmed by thick, insulated walls and highly efficient condensing boilers.

Overhead, WeatherNation plays on the television, looping footage of last year's mega storms and flashing a headline: "2022 billion dollar disasters."

The Paris Olympics is going underground to find a way to keep athletes cool at the 2024 Games without air conditioners.

Organizers are planning to use a water-cooling system under the Athletes Village — much like the one that has helped the Louvre Museum cope with the sweltering heat that broke records last year — to keep temperatures in check for the Olympians and Paralympians who stay there.

A major new United Nations report being released Monday is expected to provide a sobering reminder that time is running out if humanity wants to avoid passing a dangerous global warming threshold.

The report by hundreds of the world's top scientists is the capstone on a series that summarizes the research on global warming compiled since the Paris climate accord was agreed in 2015.

The European Union has presented plans to fundamentally revamp its policies on promoting green technologies and dealing with critical raw materials, imposing limits on imports from countries like China while unleashing subsidies and other financial incentives to ramp up home production.

The plans by the European Commission, the EU's executive arm, are essential in moving toward a climate neutral economy, while also increasing the bloc's strategic independence in a shifting world of geopolitical alliances.

Authorities are still getting to grips with the scale of Cyclone Freddy's destruction in Malawi and Mozambique since late Saturday, with over 370 people confirmed dead, several hundreds still missing and tens of thousands displaced.

On Friday, Malawi authorities said Freddy killed at least 326 people, with 200 still missing. There are hundreds of evacuation centers set up across the country for survivors. Malawi's president, Lazarus Chakwera, declared a 14-day national mourning period on Thursday.

Climate change attacked crucial Arctic sea ice thickness in two sudden big gobbles instead of steady nibbling, a new study says.

A little more than 15 years ago, sea ice quickly lost more than half its thickness, becoming weaker, more prone to melting and less likely to recover, according to the study that emphasizes the importance of two big "regime shifts" that changed the complexion of the Arctic.