The doomsday glacier: Separating fact from fear

Ever since global warming came to be a part of humanity’s collective conscious around half a century ago, scientists, international organizations and world leaders have been racing against time to mitigate the effects of this looming threat. While the world has failed to make significant strides in combating climate change, a new study into the Thwaites Glacier, located in Antarctica, has spelt more bad news.

The research, which was conducted over the span of six years by a team of 100 scientists, has found that the glacier is melting at an increasing rate and could raise the global sea levels by an alarming degree.

The Thwaites Glacier , also referred to as the Doomsday Glacier, has been an important subject of scientific research since its identification in 1947. Owing to its expanse, which is pegged to be larger than Florida and roughly the size of Britain, the glacier’s collapse could raise sea levels by 65 centimeters. What is even more concerning is that its collapse would likely cause the depletion of the ice sheet covering West Antarctica, in turn resulting in a sea level rise of 10 feet. Such an event would prove disastrous for New York, Shanghai, Tokyo, Mumbai and other coastal cities the world over.

The study was done by International Thwaites Glacier Collaboration (ITGC), a joint research program of US and UK scientists, at the cost of $50 million. The aim of the study was to understand the physical processes in the present climate and over the last few thousand years that have maintained the glacier. The findings would help better gauge how the glacier would react in the coming decades.

According to marine geophysicist Dr Rob Larter, who was part if the ITGC, “Thwaites has been retreating for more than 80 years, accelerating considerably over the past 30 years, and our findings indicate it is set to retreat further and faster.”

Small innovations to aid study

The major challenge faced by scientists was to overcome the glacier’s remote and harsh environment to employ technological tools and methods. While the physical processes that drive glacier retreat still need to be pieced together, technological advances are helping scientists gather more detailed and accurate information. Small innovations that work in tandem with large-scale geoengineering projects have proven beneficial in looking for the right answers.

“What may seem like small innovations, given the amazing advances elsewhere in, for example, space exploration or artificial intelligence, would have a huge impact on the field. AUVs (autonomous underwater vehicles) are well within our reach but science budgets are not suited to the relative impact these topics will have on society,” said Dr Ted Scambos, the US science lead of the International Thwaites Glacier Collaboration in an interview to Interesting Engineering . In Scambos’ view, science budgets have yet to adjust to the relative impact the study of topics such as sea level rise, polar science, and polar climate change will have on society. “We don’t need $100 billion to build a wall in the ocean. We need $1 million to know if we should try. And right now, $10 million is a huge amount for this area,” he added.

Robot Icefin dives to help

The bedrock of Thwaites sits hundreds of meters below the sea level. This further complicated research for ITGC. That’s when Icefin , a small cigar-shaped, remotely-operated underwater robot, dived to help. Measuring about 3.5 meters long and weighing around 286 pounds, Icefin is equipped with numerous sensors and is designed to pass through narrow boreholes.

Icefin dug a roughly 2,000-foot-deep tunnel in the ice and what it recorded surprised the entire ITGC team. Scientists had the opportunity to see the grounding line of the glacier for the first time. A key point of vulnerability is when the ice rises from the seabed and begins to float. According to the findings, the glacier is melting in unexpected ways, with warm ocean water flowing through deep cracks. Under the glacier, a thin layer of cold water acts as isolation. However, tidal waves bring warmer seawater to places where the ice breaks away from the bottom. This happens under high pressure even 10 kilometers deep. The warm air breaks the layer of cold water, accelerating the glacier’s retreat from the point where it touches the seabed.

“We’ve done a lot to learn about the ocean and the landscape beneath the ocean and the ice. We have improved models greatly to address some of the new observations; but not all of them. Probably the most urgent, interesting thing is to understand the impact of sub-ice intrusions by the ocean due to tidal pumping. But I think everyone wants more consistent observations, lasting for years, and year-round; and then incorporate the new physical processes, first in schematic models and then in climate-linked models,” Scambos told IE.

There’s so much we don’t yet know

On the question of how difficult it is to identify gaps in our understanding of the physical processes driving Thwaites retreat, Scambos observed it is like a puzzle. “A story with surprise twists. You might think that the arrangement of muddy areas and rocky areas would not matter beneath the ice, or that one type of bed surface would be the one that was the riskiest. But we are learning that a mixed bed, which is the reality, is the one that leads to the fastest retreat,” he explained. The results of the research show that the tide causes rapid melting.

Professor Douglas R. MacAyeal is one of the authors of Glacial Climate Intervention: A Research Vision. The paper presents a perspective on future research directions and is informed by discussions on glacial climate intervention from workshops held at the University of Chicago in 2023.

“The messages are very, very messy and hidden and difficult to read or to see or understand. And, indeed one of the hardest issues with earth science and with glaciology is figuring out if something is happening. Is the Thwaites Glacier in the process of changing global sea level by 2 or 3 meters over the next 100 years or so?” questioned MacAyeal. He explained that the data supports both ideas as possible outcomes. However the most accepted notion is that sea level rise is slightly more probable in the future than stability or slow growth of the Thwaites Glacier.

“But it may be that artificial intelligence will ultimately be the deciding factor that penetrates the uncertainty of the data to give people some kind of a reliable forecast that is worth to making taking action,” added MacAyeal. According to him, artificial intelligence could also be useful for figuring out things that happen only rarely. On the other hand, AI could help us answer a very tough scientific problem: How do you tell when something has begun?

The Thwaites Glacier melts on its bottom, detaching it from its bed and making it float. Hence, all of the interventions at Thwaites Glacier are oriented towards stopping this from happening and slowing the ice flow. But as MacAyeal puts it, the methods are all science fiction “Nobody’s ever tried anything like this,” he told IE. The two basic techniques suggested in the study co-authored by him are building a shower curtain like structure and stopping the ice from melting or removing the water at the bottom.

“One idea is to put a curtain in front of the ocean and Thwaites Glacier. This would be 50 to 100 kilometers of fabric that would protect the glacier from heat in the ocean as the ocean warms.” On the other hand, “If you could remove that water or make it freeze, it would stop moving at 3,000 meters per year and start moving at a slower rate, like 30 meters per year. That would eliminate the sea level threat. A handful of glaciologists have proposed those ideas,” he concluded.

The questions that remain

However, many questions remain. How can we improve computer models to show that they can replicate the changes of the past 40-80 years? Is the retreat of the Thwaites Glacier now irreversible? Are there mechanisms that could stop the withdrawal? If they exist, what climatic conditions would be necessary for them to occur? To what extent could increased snow accumulation compensate for future ice loss? How do ice-ocean interactions beneath the ice sheets affect the melting rate?

On being asked if the nickname ‘ Doomsday Glacier ‘ given to Thwaites was justified, MacAyeal said that in about 50 years, the front of Thwaites will be near the main under-ice ridge, which has been identified as a major factor in holding it back. “How it retreats past that, and what happens in the deep basin beyond it is of great concern. All the models show that it begins an unstoppable process of evacuating the ice from West Antarctica at a mind-boggling rate. We have never seen anything like what the models show us could happen,” he added.

Understanding the rate of Thwaites’ decline is important, but more needs to be done globally. MacAyeal says it would be wise for the ITGC to research this area consistently. “The National Science Foundation and Natural Environment Research Council are ‘taking a break’ and have a lot of data and ideas to digest. The next move will have to wait, among other things, for the right budget.”

Making the right choices

People’s choices today will determine how quickly change will occur. MacAyeal says a key decision is de-carbonizing the economy as quickly as possible. “Wind and solar are cheaper than fossil fuels in many cases, with the right grid, much cheaper. This will transform low carbon emissions relatively faster.”  He thinks that in the next twenty years, we will realize that ending our contribution to the greenhouse is not enough. According to the professor, we will have to consider the challenge of removing the carbon already in the atmosphere.

As he points out, the main conclusion of his work is that Thwaites Glacier is unlikely to be on the verge of a catastrophic collapse in the next few decades. However, the long-term threat is real and almost inevitable. MacAyeal adds that our choice is whether we start acting now to slow the pace of almost certain collapse or push the system to the brink and pass it by the end of the century. Although it may seem far away, he concluded that “people living today, quite a few people, will see this collective decision unfold during their lifetimes.”

Although the Thwaites Glacier is not expected to collapse imminently, its long-term destabilization could have devastating consequences. Advanced technologies, like artificial intelligence, could help unravel complex glaciological data and provide clearer predictions for future changes. Ultimately, bold and forward-thinking strategies will be crucial.