Study shows Thwaites Glacier just isn’t collapsing like dominoes as feared, but that doesn't mean 'doomsday glacier' is stable

The Thwaites Glacier in Antarctica was nicknamed “Doomsday Glacier” for its potential to flood coastlines all over the world if it collapses. It is already contributing to about 4% of annual sea level rise because it loses ice, and one theory is that the glacier will soon begin to fall into the ocean like a row of dominoes.

But is such a rapid collapse really as likely as feared? A brand new study on the vulnerability of the Thwaites Glacier to the so-called Instability of the ocean ice cliff gives some hope. But The results doesn’t mean that Thwaites is stable.

Polar explorer Mathieu Morlighemwho led the study, explains the outcomes.

Why is the Thwaites Glacier so vital?

The Thwaites Glacier drains an enormous area of ​​Antarctic ice – about 74,000 square miles (192,000 square kilometers), an area larger than Florida. If a snowflake falls into this drainage system, it’ll eventually find yourself as a part of an iceberg within the sea off Thwaites.

What we’re currently seeing at Thwaites Glacier is a catastrophe in slow motion.

The bedrock beneath the Thwaites Glacier lies below sea level and Slopes inlandin order that the glacier penetrates deeper into the ice sheet. Once the glacier loses more ice than it gains in latest snow and retreats, it is vitally difficult to slow it down for this reason inclination. And Thwaites is already retreat with increasing speed because the climate warms.

The Thwaites Glacier accommodates enough ice to lift global sea levels by greater than 2 feet (0.65 meters). As soon as Thwaites begins to destabilize, it’ll also Destabilization of neighboring glaciersSo what happens to Thwaites affects the complete West Antarctic Ice Sheet, and that in turn affects sea level rise along coasts in all places.

What is marine ice cliff instability?

The instability of marine ice cliffs is a relatively latest concept proposed by scientists over the past decade.

Many of the glaciers in Antarctica have huge floating extensions, the so-called Ice shelf that support the glacier and slow its flow of ice into the ocean. With global warming, a few of these floating extensions have collapsed, sometimes in a short timeinside a couple of weeks or months.

If the Thwaites Ice Shelf were to collapse, it will expose a really high ice cliff facing the ocean. 75 miles (120 kilometers) long front. Ice can only withstand a specific amount of force, so if the cliff is just too high, it’ll collapse into the ocean.

Once this happens, a brand new ice cliff can be exposed further back, and the brand new cliff can be even higher since it is further inland. The theory of marine ice cliff instability assumes that if the cliffs collapse fast enough, could have a domino effect of ever higher ice cliffs collapsing one after the opposite.

However, nobody has ever observed sea ice cliff instability in motion. We don't know if it’ll occur because much relies on how quickly the ice collapses.

What have you ever discovered concerning the risk to Thwaites?

If the Theory of instability of marine ice cliffs When this model was first introduced, it served as a rough estimate of the chance of ice cliff collapse once the ice shelf has disappeared.

Studies have since shown that Ice cliffs is not going to collapse systematically until the ice is about 135 meters high. Even then, they might cave in more slowly than planned until they were much higher.

We used three high-resolution models to research what this latest physical understanding of ice cliff instability would mean for Thwaites Glacier this century.

Our results show that if the complete Thwaites ice shelf were to collapse today, its ice front wouldn’t retreat inland as quickly resulting from the instability of the ice cliffs alone. Without the ice shelf, the glacier's ice would flow much faster towards the ocean, thinning the glacier front. As a result, the ice cliffs wouldn’t be as high.

We found that Thwaites would remain relatively stable not less than until 2100. We also simulated a collapse of the ice shelf in 50 years if the Grounding line of a glacier – where the ice washed ashore meets the ocean – would have retreated further inland. But even then, we found that the instability of the ice cliffs alone wouldn’t cause rapid retreat.

The results challenge some recent estimates of how quickly Thwaites could collapse, including a worst-case scenario that the IPCC utilized in its latest evaluation report but marked as “low probability”.

Thwaites is the glacier that worries everyone. If you model the complete ice sheet, that is where the instability of the marine ice cliffs begins and where it spreads far inlandSo if Thwaites just isn’t as vulnerable to ice cliff collapse as we thought, that’s a superb sign for the complete ice sheet.

However, the instability of sea ice cliffs is just certainly one of the mechanisms of ice loss. This finding doesn’t mean that Thwaites is stable.

What other causes are causing glaciers to retreat at an ever faster rate?

There are many processes that make the Antarctic ice sheet unstable, a few of that are thoroughly understood.

Explaining interactions between ice and ocean many of the recent ice mass loss up to now. Antarctica is a very cold placeSo the warming of the atmosphere has not yet had a significant impact. But warm ocean currents are reaching under the ice shelves, they usually are thin the ice from belowwhich weakens the ice shelves. When this happens, the ice streams flow faster because there may be less resistance.

About the the last a long timeIn the sector of the Amundsen Sea, where the Thwaites and Pine Island glaciers are positioned, warm water from the Antarctic Circumpolar Current has penetrated, which melt the ice from below.

What does climate change need to do with it?

Antarctica may appear to be a faraway place, but Human activities that warm the planet – akin to the burning of fossil fuels – are having dramatic effects on the poles. The lack of ice contributes to the rise in sea levels, Impacts on coastal regions all over the world.

The decisions people make today will determine how quickly water levels rise.