This story was produced in partnership with the Pulitzer Center’s Ocean Reporting Network.
BAKU, Azerbaijan—During 2024, the hottest year on record, snowpack in the Himalaya Mountains has plummeted to unprecedented lows, the Arctic has become a net carbon emitter, and once stable Antarctic sea ice appears to be permanently melting.
The deterioration of the planet’s snow and ice regions, from the high peaks to the poles, has already unleashed deadly glacial floods and raised sea levels by more than 11 centimeters. This is costing the world billions of dollars in damages, according to a State of the Cryosphere report presented this week at the 29th Conference of the Parties to the United Nations Framework Convention on Climate Change (COP29), the U.N.’s annual climate summit, in Azerbaijan. If emissions don’t stop increasing, society could face a disastrous sea-level rise of one meter, coupled with the collapse of a system of ocean currents crucial to the planet, by 2100.
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At an event in Azerbaijan following the report’s release, officials from Chile, Germany, Norway and Pakistan pressed countries at the summit to pledge deeper emissions cuts. The officials belong to a group of 23 governments lobbying for action against ice loss.
“This is not a regional problem. This is a global problem,” said Ahmad Atteeq Anwer, parliamentary secretary of Pakistan’s climate change ministry. “Climate change happening at one end of the globe will not stay there. It will affect every one of us.”
But fossil fuel emissions continue to rise, according to the latest annual Global Carbon Budget report, published by international researchers on November 13. And incoming U.S. president Donald Trump has vowed to exit the 2015 international Paris Agreement on climate change efforts—and to drill for more oil. This year the global average temperature reached 1.5 degrees Celsius above the preindustrial level for the first time, temporarily breaching the long-term limit that countries agreed to strive for in the Paris Agreement.
Above 1.5 degrees C, humanity risks crossing tipping points that could set off dramatic, irreversible melting. The world is on track for three degrees C of warming by 2100, and countries’ current commitments to reduce emissions would shave less than a degree off that. Nations are supposed to publish new targets by February—and are under pressure at COP29 to guarantee hundreds of billions of dollars in annual financing to efforts aimed at reaching those targets.
“We still have time to make a course correction,” said Maisa Rojas, Chile’s environment minister and a prominent climate scientist, at the conference. “The only way to mitigate and prevent these global impacts from ice loss is through swift reduction to carbon emissions.”
At current emissions levels, almost all small and low-latitude mountain glaciers would be wiped out by 2100. Asia has suffered record ice loss this year. On August 16 walls of ice around two melt lakes on Nepal’s Thyanbo Glacier burst, sending a cascade of water, ice, rock and sediment crashing through Thame, the home village of mountaineer Tenzing Norgay, the first person to reach the summit of Everest, with noted mountaineer Edmund Hillary. No one was hurt; village schoolchildren had been sent home early that day, and many residents were elsewhere because the climbing season was over. But the school, a health clinic, five hotels and seven homes were destroyed, and half the village was rendered uninhabitable.
These glacial lake outburst floods, as they are known, currently threaten 10 million people, mainly in Asia and North and South America. On August 6 one such flood raised a river in Juneau, Alaska, nearly five meters in a matter of hours, swamping almost 300 homes and prompting the city to allocate $2 million for flood barriers. Glacial floods partially destroyed a $1.69-billion hydropower dam and killed 42 people in India last year; they also contributed to the catastrophic monsoon flooding in Pakistan in 2022.
The melting of glaciers and mountain snowpack is also undermining water supplies. The COP29 host city of Baku gets a quarter of its drinking water from glaciers that are now retreating. In the Hindu Kush Himalaya mountains, which stretch from Pakistan to Myanmar, rivers fed by glaciers and snow provide water for drinking, irrigation and hydropower to two billion people and generate $4 trillion in economic activity. The region suffered its lowest ever snowpack last winter, leaving normally white mountainsides brown.
And the deterioration of ice and snow is triggering feedback loops that will heat the world even further. Permafrost, the frozen ground that holds twice as much carbon as is currently found in the atmosphere, is thawing and releasing these stores. Warming temperatures do mean plant growth there is increasing and drawing down more carbon dioxide from the atmosphere—but research has revealed that the permafrost zone is now releasing more carbon than it absorbs, heating the planet further.
Melting sea ice is speeding up other consequences as well. White ice reflects sunlight back into space, but blue water absorbs it. In the Arctic, sea ice has shrunk 40 percent in the past 40 years. In the Antarctic, sea ice extent has fallen below two million square kilometers for the third summer in a row, an unprecedented development that suggests a “regime shift” from seasonal variation to long-term retreat.
“Last year, in my own homeland, we saw how the sea ice didn’t settle,” said Sara Olsvig, chair of the Inuit Circumpolar Council, who is from Greenland, at the conference. “Families in the north lost their access to go hunting [for seals and small whales]…. The government of Greenland had to reach into its own catastrophe funds.”
In several areas, we’re approaching a point of no return. Recent modeling has shown it’s too late to avoid at least some melting of the West Antarctic ice sheet. And the Greenland ice sheet is now losing 30 million metric tons of ice—the size of 250 cruise ships—every hour on average, according to the report.
That is in turn threatening the vital Atlantic Meridional Overturning Circulation (AMOC), a phenomenon in which warm surface water from the tropics flows toward the North Pole. There the water gets saltier and colder, which makes it sink and then return southward along the ocean floor.
But the growing influx of freshwater from melting Greenland glaciers and Arctic sea ice is slowing the cascade of dense, salty water that drives this current. The AMOC is predicted to weaken by up to two thirds over this century, and 44 climate scientists warned this year that we’ve “greatly underestimated” the risk that it could collapse entirely. If that happened, northern Europe could cool by more than three degrees C per decade.
“It means a massive reduction in the amount of heat that comes out of the low-latitude North Atlantic and keeps Britain warm,” said Robbie Mallett, a sea ice scientist at the Arctic University of Norway. “It keeps the fisheries going in northwestern Europe, which is really, really important.”
The financial price of all this melting is hard to quantify, but experts who delivered the report at COP29 say it is in the billions of dollars and growing. Alaska is already spending hundreds of millions of dollars repairing permafrost thaw damage to infrastructure, and across the Arctic, these costs could rise to $276 billion by the middle of this century. In Antarctica, fishing and tourism earns $1.2 billion annually. And the benefits Antarctica provides to the planet by storing carbon, reflecting solar heat and keeping sea levels low are worth $180 billion per year, recent research estimated.
At least $8.1 billion of the $60 billion in damages from when Hurricane Sandy hit the U.S. East Coast in 2012 was caused by sea-level rise, researchers found.
If seas rise one meter by 2100, parts of Amsterdam, Bangkok, Karachi, Miami, Vancouver and other cities would be underwater, displacing millions of people. But if we limit warming to 1.5 degrees C, we could halve that rise. Slowing the melt even a little would buy time to adapt, reducing damage and deaths.
“Every tenth of a degree truly matters,” said Heïdi Sevestre, a glaciologist at the Arctic Council’s Arctic Monitoring and Assessment Program. “How many more warnings, how many more lives before we find the political courage to give ourselves a fighting chance?”
