Scientists have detected dangerous melting beneath the “Resurrection Glacier” in Antarctica

Thwaites Glacier, an ice formation the size of Florida, could change the world. And the latest research shows that some of the most vulnerable regions are at greater risk than previously thought.

Thwaites contains a massive amount of ice enough to gradually raise sea level by more than 2 feet(Opens in a new tab), although its collapse in a hot climate could unleash many feet of nearby glaciers. The Antarctic glacier has been destabilizing, retreating nearly nine miles since the 1990s. If much of it gradually melted in the coming decades and centuries, huge swaths of coastal cities and populated areas around the world could be flooded, and easily battered by storms. For this reason, scientists are now searching intensely for where Thwaites melted and How quickly can it melt. These are huge questions for the future inhabitants of the Earth.

Take it from researchers traversing the continent’s harsh icy plains to document the rapid changes at Thwaites.

“Thwaites is the only spot in Antarctica that has the potential to drain an enormous amount of water into the ocean over the coming decades,” Sridhar Anandakrishnan, a professor of glaciology at Penn State University, told Mashable in 2021.

This is why, for better or worse, Thwaites has earned the nickname “Doomsday Glacier.” Crucially, climate scientists assert, civilization is not inherently doomed. We are not unhappy. We have the energy choices that can limit the worst consequences of climate change.

The latest 2023 research, straight from a West Antarctic source, shows how the glacier is melting. The critical point is below the Thwaites Ice Shelf, which is the end of the glacier that reaches over the ocean. Crucially, ice shelves were projecting themselves into the ocean floor, acting somewhat like a “cork in a bottle” to prevent the rest of the massive glaciers from flowing unimpeded into the sea. So if the ice shelf eventually goes away, so could the glacier (although this process progresses from several decades to centuries).

Glaciologists drilled through nearly 2,000 feet of Thwaites ice shelf to lower a miniature yellow submarine-like robot called Icefin, into the dark waters, allowing them to see what’s going on in this poorly grounded area. the Recent research(Opens in a new tab)Just Published in the journal Science nature(Opens in a new tab)And It shows two main results:

• The glacier continues to melt underwater, but along the flat areas that make up the majority of this ice shelf, this thinning is happening more slowly (about six to 16 feet, or two to five meters, per year) than the researchers expected.

• Until now, Thwaites are melting faster than expected in cracks under the critical floating ice shelf. Scientists believe that relatively warmer water seeps into natural fissures and fissures, amplifying melting at these weak spots (as seen in the snapshot below).

“Thwaites is the only spot in Antarctica that has the potential to drain a huge amount of water into the ocean over the coming decades.”

While glaciologists are still uncovering the complex mechanisms of underwater melt, the bigger picture is clear. The glacier is losing ice. And only small amounts of ice loss in this critical grounding zone may result in a large total ice loss.

“Our results are a surprise but the glacier is still in trouble,” says Peter Davis, an oceanographer with the British Antarctic Survey who made some of the recent measurements at Thwaites, he said in a statement(Opens in a new tab). “If the ice shelf and glacier were in equilibrium, the ice coming off the continent would match the amount of ice that is lost through melting and the formation of icebergs. What we found is that despite small amounts of melt, there is still a rapid retreat of glaciers, so It doesn’t seem like it takes much to get the glacier out of balance.”

What scientists saw under Doomsday Glacier

On the recent trip to West Antarctica, the researchers set up camp on the remote ice shelf at Thwaites and dropped the robot Icewedge into the water below. The rare images shown in the British Antarctic Survey video below reveal what happens to thin ice. Melting in the crevasses has left “staircase-like” formations on the lower side of the Doomsday Glacier.

“Warm water enters the cracks, helping to erode the glacier at its weakest points,” Brittney Schmidt, an associate professor of astronomy and Earth and Atmospheric Sciences at Cornell University who worked on Thwaites’ new research, said in a statement.

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Icefin footage is invaluable, because there is currently no other way to access this nearly inaccessible area in one of the most remote places on Earth. The new footage underscores an important point: Researchers have yet to fully understand the melting processes beneath one of the world’s largest and most important glaciers.

“It shows us that this system is very complex and requires rethinking how ice melts in the ocean, especially at a site like Thwaites,” Davis said.

On this map of Antarctica, the Thwaites Glacier is visible on the left, located in West Antarctica.
Credit: British Antarctic Survey

What is the expected rise in sea level?

Already, sea levels globally It has risen by about eight to nine inches since the late nineteenth century(Opens in a new tab). But there’s more in store.

• Today, Thwaites is melting It contributes four percent(Opens in a new tab) to sea level rise in the ocean. But in the coming decades and centuries, this number may increase if the glacier breaks away from the ocean floor and “the cork pops out of the bottle,” so to speak. Ice can flow unimpeded into the sea, which eventually leads to foot from sea level rise.

• Sea level rise is accelerated by melting ice and thermal expansion of the oceans. Seas are currently rising about one-eighth of an inch each year. From now until 2050, the National Oceanic and Atmospheric Administration (NOAA) It expects sea levels around the United States to rise by another foot(Opens in a new tab).

• By the end of the century, climate scientists estimate that global sea levels will generally rise by about 1.5 to 2.5 feet, and will continue to rise. How much depends largely on how massive glaciers like Thwaites and nearby Pine Island respond to warming conditions and warmer waters.

Ocean heat content has been rising for decades because the seas absorb more than 90% of the heat that humanity traps on Earth.
Credit: NOAA

Most importantly, the effects of global warming on glaciers like Greenland and Antarctica hinge largely on the unpredictable part of the climate change equation: humans. Driven by massive fossil fuel burning, heat-trapping carbon dioxide has risen in the atmosphere in the past century. Carbon dioxide levels are now the highest they have been in more than 3 million years. How high will they rise?

[This story was originally published on Feb. 18 and has been updated with more information about the Thwaites Glacier.]