The Mona Lisa may maintain her famously enigmatic smile because she benefits from one of Paris' best-kept secrets: An underground cooling system that's helped the Louvre cope with the sweltering heat that has broken temperature records across Europe.

The little-known "urban cold" network snakes unsuspecting beneath Parisians' feet at a depth of up to 30 meters (98 feet), pumping out icy water through 89 kilometers (55 miles) of labyrinthine pipes, which is used to chill the air in over 700 sites. The system, which uses electricity generated by renewable sources, is the largest in Europe — and chugs on around the clock with a deafening noise totally inaudible above ground.

Richer countries failed to keep a $100 billion-a-year pledge to developing nations to help them achieve their climate goals, according to an analysis by the Organization for Economic Cooperation and Development, or OECD.

$83.3 billion in climate financing was given to poorer countries in 2020, a 4% increase from the previous year, but still short of the proposed goal. The United Nations-backed payment plan was first agreed in 2009 to help poorer nations adapt to the effects of climate change and reduce emissions.

Crews battling the largest wildfire so far this year in California braced for thunderstorms and hot, windy conditions that created the potential for additional fire growth Sunday as they sought to protect remote communities.

The McKinney Fire was burning out of control in Northern California's Klamath National Forest, with expected thunderstorms a big concern Sunday just south of the Oregon state line, said U.S. Forest Service spokesperson Adrienne Freeman.

So-called "ultra-fast fashion" has won legions of young fans who are able to snap up relatively cheap clothes online, but campaigners say the trend masks darker environmental problems. 

Hundreds of young climate activists marched through Turin on Friday, after a week of discussions on the future of the increasingly global school strike movement.

Spanish Prime Minister Pedro Sanchez on Friday called on office workers to throw sartorial caution to the wind and ditch their ties amid scorching summer temperatures.

Search and rescue teams backed by the National Guard searched Friday for people missing in record floods that wiped out entire communities in some of the poorest places in America. Kentucky's governor said 15 people have died, a toll he expected to grow as the rain keeps falling.

"We've still got a lot of searching to do," said Jerry Stacy, the emergency management director in Kentucky 's hard-hit Perry County. "We still have missing people."

To the naked eye, the Mako Compressor Station outside the dusty West Texas crossroads of Lenorah appears unremarkable, similar to tens of thousands of oil and gas operations scattered throughout the oil-rich Permian Basin.

What's not visible through the chain-link fence is the plume of invisible gas, primarily methane, billowing from the gleaming white storage tanks up into the cloudless blue sky.

A large wildfire on the German-Czech border is spreading and threatening to destroy a forested national park popular with tourists.

The fire in the region, called Bohemian Switzerland on the Czech side and the Saxon Switzerland national park on the German side, started last weekend. It had seemed to be under control but spread again early Thursday, German news agency dpa reported.

The world's most influential banks need to substantially accelerate climate efforts if global temperature rise is to be kept within the targets of the Paris Agreement, an assessment released Thursday by an institutional investors group warned.

The efforts of 27 giant banks in North America, Europe and Asia to align their policies with global warming of no more than 1.5 degrees Celsius (2.7 Fahrenheit) are falling far short in every area measured in the pilot study, obtained exclusively by The Associated Press. The report said no major bank has committed to end financing for new oil and gas exploration, and only one has promised to cut all coal financing in line with International Energy Agency guidelines.