Tag Archives: shelf

Imminent Collapse of Doomsday Glacier’s Massive Ice Shelf: What You Need to Know

Posted on by
Reply

The South Korean icebreaker “Araon” navigates through sea ice near the Thwaites Glacier in January 2026.

Chang W. Lee/New York Times/Redux/eyevine

The front ice shelf of Thwaites Glacier is on the brink of collapse, increasing the instability of Antarctica’s most vulnerable glacier.

“Its imminent demise could occur suddenly, and to clarify, we are preparing an ‘obituary’ press release,” states Rob Larter from the British Antarctic Survey.

Thwaites Glacier, often referred to as the ‘Doomsday Glacier’, is approximately the size of the United Kingdom, rapidly shrinking and currently contributing to around 4% of global sea level rise. Furthermore, its collapse might instigate a domino effect across the West Antarctic ice sheet, leading to an alarming 3.3 meters of sea level rise and reshaping coastlines globally.

Numerous glaciers in Antarctica have ice shelves that float into the ocean, aiding the flow of ice from the continent. This includes the Eastern Thwaites Ice Shelf (TEIS), roughly the size of Greater London (1,500 square kilometers) and boasting a thickness of 350 meters. Recent satellite imagery reveals troubling indications that this ice shelf may soon become detached, with some experts asserting that this separation has already commenced.

“Suddenly, extensive areas were torn apart,” remarks Christian Wilde from the University of Innsbruck, Austria. “It resembles a shattered windshield.”

Significant cracks have emerged around the pinning points (the sections where the floating ice shelf is secured by underwater ridges) and along the grounding line, the area where the glacier transitions into the ocean and begins to float.

“It’s dramatic. I visited in 2019 or 2020, and now when I look at the satellite image, I can’t identify that ledge. There’s a considerable notch where there was none before,” comments Karen Alley, a professor at the University of Manitoba in Canada, who is examining how this divide might progress.

The primary cause of these changes is shifts in ocean circulation, which have led to the melting and thinning of the ice. Additionally, alterations in ice flow dynamics mean the shelf is colliding with stable points, causing fractures. “We’re transitioning from a robust, thick ice shelf anchored at specific points to a weakened, thinner ice shelf that’s disintegrating,” Alley explains.

The disappearance of ice shelves is also evident in the speed at which they flow. “From January 2020 to January 2026, the ice flow has tripled to over 2,000 meters per year, which is alarming,” Wilde states. This trend has intensified in the last five months. “We’re essentially in a state of free fall at this point.”

Simultaneously, fresh cracks are appearing along the grounding line. “These have emerged in the past few years as shelf displays have significantly accelerated,” comments Ted Scambos from the University of Colorado Boulder. This indicates that ice shelves are being pulled away from glaciers.

Predicting the exact moment of final breakup is exceedingly complex. “Forecasting ice shelf rupture is akin to predicting earthquakes,” Larter explains. “We recognize an event is in motion, but timing is reliant on unpredictable processes. The next satellite image we receive may reveal ice shelf collapse, but the same could be true next year.”

However, don’t expect a colossal iceberg to float into the ocean immediately. Due to the area’s geography, any detached ice is likely to remain in proximity, and, since TEIS is already so fractured, significant breaks are improbable.

While the dramatic collapse of giant icebergs often captures headlines, glaciologists emphasize that the primary concern lies in the diminishing strength of the ice shelf. Wilde remarks that the shelf is “effectively gone” when it ceases to impede the upstream flow. This results in a quicker movement of glaciers into the ocean.

In an upcoming study, Wilde and colleagues revealed that from January 2020 to 2026, the ice flow of glaciers previously supported by TEIS increased by roughly 33 percent. “There is evident proof that there is little to no buttressing in this region anymore,” he states. This reduction has effectively led to the collapse of the ice shelf.

This poses significant implications for future global sea levels. “Increased ice movement from Antarctica means more ice entering the ocean, contributing to rising sea levels,” Scambos notes, emphasizing that while this is not an immediate crisis, it will slowly unfold, affecting future sea levels over decades. “This will influence how Thwaites evolves and potentially contributes to 10 to 20 percent of future sea level rise.”

By 2067, Thwaites may lose approximately 190 gigatonnes of ice annually according to a January study by Daniel Goldberg from the University of Edinburgh and colleagues. This marks a 30 percent increase over current glacier losses, equating to the total ice currently lost from Antarctica.

While ice shelf break-offs are normal in polar cycles, current loss trends are alarming. “Since the 1990s, we’ve observed increasing instability in ice shelves,” Alley states. Notably, the adjoining Pine Island Glacier is also undergoing rapid changes, and its ice shelf is collapsing.

“Ice shelves remain stable primarily in extremely cold conditions,” Alley adds. “Both ocean and atmospheric temperatures must be low. However, as we warm the planet, we observe the corresponding loss of ice shelves, which is precisely what’s expected.”

Topic:

Source: www.newscientist.com

Undersea ‘Storm’ Melts Ice Shelf of Terminal Glacier

Posted on by
Reply

Thwaites Glacier, West Antarctica

NASA/ZUMA wire/shutterstock

A submerged “storm” is eroding the ice shelf that shields Antarctica’s Thwaites “Terminal” glacier, prompting concerns that scientists may be underestimating future sea level increases.

These storm-like currents, referred to as “submesoscale” features, can extend up to 10 kilometers wide and begin to form when water with varying temperatures and densities collides in the open ocean. This process is akin to hurricanes that arise from gas mixtures in the atmosphere. Similar to hurricanes, these currents can surge toward the coast, with Antarctica predominantly consisting of ice shelves—floating extensions of glaciers that project tens of kilometers into the ocean.

“Their movements are so unpredictable that halting them is quite challenging,” states Mattia Poinelli from the University of California, Irvine. “The only course of action is for them to become trapped beneath the ice.”

Poinelli and colleagues’ modeling indicates that these submesoscale formations were responsible for one-fifth of the total ice melt in the Thwaites Mountains and nearby Pine Island over a nine-month timeframe. This research marks the first attempt to quantify the influence of these storms across the entire ice shelf.

Ice shelves play a crucial role in hindering the movement of glaciers into the sea and shielding them from wave erosion. The vulnerable Thwaites Glacier annually loses 50 billion tons of ice and could raise sea levels by 65 centimeters if it collapses.

In the Antarctic waters, hundreds of meters of cold, fresh water float above warmer, saltier, deeper water. When a storm becomes enveloped within a cavity beneath an ice shelf, its swirling motions push cold surface water away from the center of the vortex, pulling warmer, deeper water into the cavity and melting the ice shelf from below.

This triggers a feedback mechanism where the melting cold freshwater interacts with the warmer, saltier water, amplifying the rotation of the underwater storm and increasing melting.

In 2022, a deep-sea float that measured temperature, salinity, and pressure was “captured” by a large rotating eddy trapped beneath the ice tongue of Stancombe Wills at another location along the Antarctic coast. The data retrieved from the captured floats showed that Katherine Hancock from Florida State University and her team estimated that the swirl causes 0.11 meters of annual melting beneath its ice tongue.

“This highlights the importance of understanding rotating eddies beneath ice shelves,” says Hancock.

The smaller submesoscale storms from Poinelli’s research are likely causing similar effects, she adds, indicating that swirling water bodies of varying sizes are contributing to significant ice melting. “There’s a need for more precise quantification,” Hancock emphasizes.

As temperatures rise and additional fresh snowmelt escapes from Antarctica, these underwater storms may increase in intensity, possibly leading to greater sea level rise than currently anticipated.

Tiago Dot of Britain’s National Oceanography Centre stated that the “unexpected” findings necessitate further observations beneath the ice shelf.

“Considering the shifts in wind patterns and sea ice around Antarctica, how much are we genuinely overlooking by not monitoring these smaller scales?” he questions.

topic:

  • climate change/
  • Antarctica

Source: www.newscientist.com

Hydrogel Extends Drug Shelf Life Beyond Refrigeration

Posted on by
Reply

When mixed with hydrogel, protein-based drugs can remain effective for longer at higher temperatures.

Shutterstock/Renko Alex

Many medicines need to be kept refrigerated or they become ineffective, but a new way of packaging protein-based drugs into a stiff gel could potentially extend their shelf life at room temperature.

If medicines are not stored properly, they can break down and become unsafe to use. For example, exposure to high temperatures can break down the chemical bonds that keep the medicine’s molecules in place, impairing their function. Shaking some medicines can cause the molecules to clump together, making them less effective. Matthew Gibson Researchers at the University of Manchester in the UK have been working to solve these challenges for almost 15 years.

He and his colleagues have developed a method to make working with protein-based drugs simpler and more practical. He said the new advances are Dave Adams Hydrogel-making researchers at the University of Glasgow in Scotland have found a way to mix proteins with gel ingredients to create hard, white structures that can be packed into a syringe. In this form, the proteins, which normally must be refrigerated at minus 20 degrees Celsius (minus 4 degrees Fahrenheit), can withstand temperatures of up to 50 degrees Celsius (122 degrees Fahrenheit) and remain functional under those conditions for up to four weeks.

Hydrogels get their stiffness from small molecules bound together in large chains that break when force is applied. In a syringe, pushing down on the plunger breaks the molecular bonds, turning the gel-protein mixture into a liquid. The hydrogel remains too large to fit through the needle, so only the drug comes out.

The team tested the method with several compounds, including bovine insulin and beta-galactosidase, an enzyme commonly used in genetic biology, and mailed themselves boxes filled with tubs of hydrogel packed with the proteins, finding that the proteins could withstand the temperature and jolts that come with going through the postal system.

There are laboratory methods that can keep proteins stable for longer, but this approach may be better suited to leaving the lab and going into the clinic, he said. Alex Brogan The King’s College London researcher says the method would be most useful in countries and regions where refrigeration is scarce and prohibitively expensive. If the new method works for protein-based vaccines, it could make disease prevention more equitable, he says.

Gibson says he and his team are confident they can produce the hydrogel on an industrial scale, but want to study its longevity and safety further. Using it in a vaccine is on their wish list, but in the short term the method could also be used to store, transport and administer the diabetes and obesity drug semaglutide.

topic:

Source: www.newscientist.com