Environment

Thwaites Glacier's critical ice shelf could collapse within five years

Thwaites Glacier in West Antarctica
NASA/OIB/Jeremy Harbeck
Thwaites Glacier in West Antarctica
NASA/OIB/Jeremy Harbeck

Data from a comprehensive study into Thwaites Glacier is painting a bleak picture. An international research team has found that a protective ice shelf will likely collapse within five years, which will speed up the destabilization of the West Antarctic ice sheet.

Thwaites Glacier spans 120 km (75 miles) along the west coast of Antarctica, and it’s a key focus for climate scientists, including the International Thwaites Glacier Collaboration (ITGC). This large glacier is particularly vulnerable to climate change – and the effects of its demise would be devastating.

“Thwaites is the widest glacier in the world,” says Ted Scambos, US lead coordinator for ITGC. “It’s doubled its outflow speed within the last 30 years, and the glacier in its entirety holds enough water to raise sea level by over 2 ft (0.6 m). And it could lead to even more sea-level rise, up to 10 ft (3 m), if it draws the surrounding glaciers with it.”

Recognizing those stakes, the ITGC was formed in 2018 to study Thwaites Glacier and monitor changes over five years. Almost 100 scientists are involved, collecting data on the ice and the surrounding water, and modeling changes into the future.

One of the most important structures is the Thwaites Eastern Ice Shelf, a floating mass of ice that braces about a third of the glacier, slowing the speed at which ice flows into the ocean. The ice shelf itself is pinned to an underwater mountain, which has kept it and the glacier relatively stable.

If Thwaites were to collapse, it would drag most of West Antarctica’s ice with it

But the ITGC found that the Thwaites Eastern Ice Shelf is under assault from multiple angles. Long channels are forming underneath the ice shelf, which allows water to flow more easily and melt the ice more efficiently.

Radar imagery shows large cracks are propagating towards the center of the ice shelf at a rate of up to 2 km (1.2 miles) per year. Worse still, these cracks are heading right for a weak zone of thin ice, which would trigger a zigzag rift pattern that would ultimately cause the entire ice shelf to collapse. The researchers calculate that this is likely to happen in as little as five years – and once the ice shelf is gone, the glacier will destabilize faster.

The mainland section of Thwaites Glacier is already under threat too. A submarine robot was sent down to examine the grounding zone, where the ice is anchored to the bedrock below. They found that the ocean water there is relatively warm and salty, which is melting the ice from underneath. Worse still, the floating ice shelf rises and falls with the tide, which works to pump water towards the glacier’s grounding zone.

The team also modeled what would happen as Thwaites Glacier retreats further inland. Very tall ice cliffs are likely to form along the ocean front, which can break off into the sea and lead to a very rapid retreat of the glacier and eventually, a collapse. This, the team says, could happen within a few decades or a few centuries.

“If Thwaites were to collapse, it would drag most of West Antarctica’s ice with it,” says Scambos. “So it’s critical to get a clearer picture of how the glacier will behave over the next 100 years.”

The ITGC will continue to study Thwaites Glacier for the next three years. The current work was presented at the AGU Fall Meeting.

Source: CIRES

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9 comments
jeronimo
Is there anything humans can do that can stop the large cracks under the ice sheet from propagating ? I think not.
joe46
ice does what ice does, that's it !
Nelson Hyde Chick
Goodbye Florida.
WeiDalong
It`s amazing that these catastrophic things are about to happen but by and large we just sit idly by and continue on with out daily lives. Everything is treated as an inconvenience nowadays rather than a threat. Covid is a good example.
SciFiHiGi
@WeiDalong We are 73 years old. Some days we aren't happy about it. Other days we are (sadly) glad that we won't be here to see the fall of civilization.
Rustgecko
The author of this piece should put an entry in his diary to follow this up in 2026 to see if the icesheet has actually collapsed. Sometimes cataclysmic predictions are made, they don't happen, but remain in our subconscious as if they actually happened. So let's see the article in 2026.
Joe123
This has got to stop. The United States is the only country that is cleaning their own environment. Other countries look to us to fund their boondoggle efforts while we are the only ones working toward the goal! And then you have people saying we are sitting idly by and doing nothing! It is amazing to me that people don't even make an effort to look at the impact, who is causing it, and what we are doing about it, and it is pathetic that this website just spouts out the leftist propaganda and doesn't tell the true story of what is happening. I hate stories like this coming from an ill informed website. Very irresponsible. All you have to do is look at a CO2 map and look at the pollution coming from countries like China and India, both have their hands out the US for money and they do absolutely nothing. How about writing a story about that if you dare.
Mark Lewus
The Earth’s ecosystem has been in a state of catastrophic collapse for at least 40 years. There is no way to stop it and civilization will not survive, nor likely will humans. I think this is the explanation for the Fermi paradox. Every time an intelligent civilization becomes industrialized, it very shortly thereafter poisons its planet or destroys itself. Or, most likely, the former followed by the latter.
ljaques
The good news is that for every glacier that melts, another is formed (or others are thickened) elsewhere on the globe (or the Antarctic continent).
This is likely similar to the way scientists and the media treated the Ross B ice shelf. They cried in horror for almost 6 years before it finally cracked off.
Nah, this couldn't POSSIBLY be connected to the 91 volcanoes they've recently (3yrs) discovered ON ANTARCTICA. ;)
As to Florida, Venice, and other coastal areas which might flood: HEY, you built homes there. Move it or lose it.