‘Unknown territory’: Antarctic glaciers melting at rate unprecedented in 5,500 years: study

Image by Angie Agostino from Pixabay
Image by Angie Agostino from Pixabay

“These currently elevated rates of ice melting may signal that those vital arteries from the heart of the West Antarctic Ice Sheet have been ruptured,” said one researcher. “Is it too late to stop the bleeding?”

By Julia Conley, Common Dreams (CC BY-NC-ND 3.0).

The human-caused climate crisis is pushing crucial glaciers in Antarctica to lose ice at a rate not seen in more than 5,000 years, according to a new study published Thursday.

Researchers at the University of Maine, the British Antarctic Survey, and Imperial College London found that the Pine Island and Thwaites glaciers on the West Antarctic Ice Sheet could cause global sea level rise of up to 3.4 meters, or over 11 feet, in the next several centuries due to their accelerated rate of ice loss.

“That the present-day rate of glacier retreat that has doubled over the past 30 years is, indeed, unprecedented.”

The glaciers—one of which, the Thwaites, has been called the “doomsday glacier” by climate scientists because of its potential to raise sea levels—are positioned in a way that allows increasingly warm ocean water to flow beneath them and erode the ice sheet from the base, causing “runaway ice loss,” the University of Maine team said in a statement.

The researchers examined penguin bones and seashells on ancient Antarctic beaches in order to analyze changes in local sea levels since the mid-Holocene period, 5,500 years ago.

Sea levels were higher and glaciers were smaller during the mid-Holocene, as the climate of the planet was warmer than it is today.

Since then, according to the study published in Nature Geoscience, relative sea levels have fallen steadily and the Thwaites and Pine Island glaciers have stayed relatively stable—until recent decades.

Ice loss was likely accelerated just prior to the mid-Holocene, and since then, the rate of relative decrease in sea levels over the past 5,500 years was almost five times smaller than it is in present day, due to “recent rapid ice mass loss,” according to the scientists.

“That the present-day rate of glacier retreat that has doubled over the past 30 years is, indeed, unprecedented,” wrote Caroline Brogan, a science reporter at Imperial College.

With the Thwaites spanning an area of more than 74,000 square miles and the Pine Island glacier spanning more than 62,600 square miles, the rapid ice loss of the two glaciers could cause major rises in sea levels around the globe.

Dylan Rood of Imperial College’s Department of Earth Science and Engineering, a co-author of the study, likened the two glaciers to arteries that have burst.

“These currently elevated rates of ice melting may signal that those vital arteries from the heart of the West Antarctic Ice Sheet have been ruptured, leading to accelerating flow into the ocean that is potentially disastrous for future global sea level in a warming world,” said Rood. “Is it too late to stop the bleeding?”

The study follows increasingly urgent calls from the Intergovernmental Panel on Climate Change, the International Energy Agency, and climate scientists around the world for an end to fossil fuel extraction, which is needed to achieve net-zero carbon emissions by 2050 and limit the average global temperature from rising more than 1.5°C above preindustrial levels.

Scientists have warned that the accelerated melting of the Thwaites glacier is likely irreversible.

“We’re going into unknown territory,” Scott Braddock, a researcher at University of Maine, told Science News. “We don’t have an analog to compare what’s going on today with what happened in the past.”

‘Big news’ for climate as global insurance giant shifts away from fossil fuels

Otogidemon, CC BY-SA 3.0, via Wikimedia Commons
30 St Mary Axe. Also known as the Swiss Re building, or Gherkin. Source: Otogidemon, CC BY-SA 3.0, via Wikimedia Commons.

The new policy by Swiss Re “is not perfect yet,” said one campaigner, but the world’s second-largest reinsurer “is headed in the right direction.”

By Kenny Stancil, Creative Commons (CC BY-NC-ND 3.0).

After Swiss Re, the world’s second-largest reinsurer, announced Thursday that it is moving to end coverage for most new oil and gas projects, climate justice campaigners who have long pushed for the insurance industry to shift away from fossil fuels offered cautious praise.

“Swiss Re is one of the world’s ultimate risk managers and the policy which it published today sends a strong message to fossil fuel companies, investors, and governments: oil and gas operations need to be phased out in accordance with climate science or they may become uninsurable by the end of the decade,” Peter Bosshard, global coordinator of Insure Our Future, said in a statement.

According to Reuters:

In its annual sustainability report on Thursday, Swiss Re said it would no longer insure projects that get the go-ahead from their parent company from 2022, unless the company has an independently verified, science-based plan to reach net-zero emissions.

By 2025, Swiss Re said it wanted half of its overall oil and gas premiums to come from companies aligned with such a net-zero by 2050 plan, and by 2030 all its clients in the sector should have done so.

Also, from 2022, the company said it will no longer insure companies or projects with more than 10% of their production in the Arctic, apart from Norwegian producers.

On the issue of treaty reinsurance, whereby it insures bundles of risk in a job lot, Swiss Re said it expected to finalize a policy for the oil and gas sector in 2023.

“By taking steps to stop insuring new oil and gas projects and companies that won’t aim at aligning their activities with climate science by 2030, Swiss Re is headed in the right direction,” said Reclaim Finance director Lucie Pinson.

“The policy is not perfect yet,” she added, “and we encourage its peers to build on it to fully align with a realistic 1.5°C scenario.”

The International Energy Agency (IEA) said last May that there is “no need for investment in new fossil fuel supply” if the world is to achieve a net-zero energy system by 2050 en route to meeting the Paris agreement’s more ambitious global warming target.

Swiss Re, said Pinson, should respond to the IEA’s landmark report by “drawing a red line against fossil fuel expansion and excluding both projects and companies that cross that line well before 2025.”

Sharing a detailed Twitter thread by Bosshard, Oil Change International celebrated Swiss Re’s move. Becoming the first major oil and gas insurer to deny coverage for most new fossil fuel projects is “big news,” said the group.

Arguing that “ending support for oil and gas projects is gaining real momentum,” 350.org also praised Insure Our Future and encouraged its campaigners to “keep up the good work.”

According to Bosshard, Swiss Re’s phase-out commitment represents “a first for the insurance industry” because it “not only applies to the up and midstream sectors, but also to downstream companies (oil refineries, gas utilities, petrochemical plants etc.) without credible net-zero plans.”

However, he continued, “the new policy includes some important gaps and contingencies.”

“It will not cover new production projects which oil companies move forward as part of their ongoing operations,” said Bosshard. “It also exempts Norway from its definition of Arctic oil. The IEA doesn’t make any such exemptions.”

“Most importantly, the policy hinges on the development of a credible oil and gas framework by the Science Based Targets initiative [SBTi], by which oil companies’ net-zero plans will be measured,” he added. “It’s crucial that the SBTi framework reflect the findings” of the IEA and the United Nations.

Swiss Re’s new policy follows similar policies adopted last week by Hannover Re and Mapfre, said Bosshard, who pointed out that “these three companies cover 21% of the global reinsurance market.”

“Now, the Insure Our Future campaign calls on Munich Re, Lloyd’s, and SCOR, which together account for 26% of the global reinsurance market, to make commitments which build on Swiss Re’s approach by the time of their annual general meetings,” said Bosshard.

“We’ll be watching,” he added.