Could underwater tsunamis beneath Antarctica’s glaciers be speeding up ice melt

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A major international research mission, led by the British Antarctic Survey (BAS), is underway to investigate a newly discovered phenomenon: powerful underwater tsunamis triggered by collapsing Antarctic glaciers.

These hidden waves are created when icebergs calve (shed and collapse) from the fronts of glaciers, and they can reach several meters in height beneath the ocean surface. They create bursts of mixing that churn together different layers of seawater.

This process is now understood to be a critical driver in redistributing heat, oxygen, and nutrients throughout the polar oceans, with profound implications for marine life and global climate regulation.

Previously, ocean mixing in the region was thought to be primarily caused by wind, tides, and surface cooling. However, early data suggest the force of these calving-generated tsunamis rivals wind-driven mixing in certain areas and exceeds tidal influences in moving ocean heat.

The discovery was made when researchers on a previous BAS expedition collected ocean data immediately before and after a calving event. Now, scientists based at Rothera Research Station and aboard the polar ship RRS Sir David Attenborough are conducting a targeted study.

The team is deploying a suite of advanced technology, including satellites, drones, underwater robots, and moorings, to capture data from dangerous, inaccessible glacier fronts. The latest technology and underwater imaging are helping scientists, as Dr. Alex Brearley, an oceanographer from the British Antarctic Survey, explains, “At the moment we’re waiting for confirmation that our controller back in Cambridge can actually see this. What I always think is really cool about one of these things is I can be sitting in the office in Cambridge, which is 10,000 km away; it’s kind of remarkable.”

The research aims to determine how different calving events generate tsunamis and how the resulting mixing affects polar ecosystems and climate. Studying deep ice cores is one way scientists can monitor climate change over centuries. There seems to be clearer evidence that human activity has accelerated climate change in the 20th century.

This article and video were provided by The Associated Press.

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[Ice collapsing into sea]

[Ice in sea]

[Penguins on ice]

[Drone shot of boat in Antarctica]

[Ice and boat]

[Whale breaching]

[Seals sleeping on ice]

[Boat pulling alongside British Antarctic Survey boat]

[Boat]

[Ice]

[Underwater shot looking at boat]

[Boat with oceanographers]

[Oceanographers lifting underwater drone]

[Oceanographers lowering drone into the water]

[Shots of the drone underwater]

Dr. Alex Brearley (interview): “At the moment we’re waiting for confirmation that our controller back in Cambridge can actually see this. What I always think is really cool about one of these things is I can be sitting in the office in Cambridge which is 10,000km away, it’s kind of remarkable.”

[Underwater shot of drone]

[Ice]

[Ice melting in the sea]

Professor Dame Jane Francis (interview): “It’s absorbing a lot of human made heat and it’s taking that heat down into the bottom of this deep ocean. And what scientists really want to know is where that heat is going and if it’s going to stay there for a long time or are we at risk of it coming back into our atmosphere – and that will affect us all.”

[Ice]

[Drone shot looking down at ice]

[Scientist walking to plane]

[Scientist stepping on metal boring rod]

[Probe entering ice]

[Scientist with probe]

[Probe entering water]

Dr. Peter Davis (interview): “Thwaites has been identified as the ice ocean system that’s most likely to affect sea level rise over the next 100 years, it’s like a keystone of the west Antarctic ice sheet, if you destabilise Thwaites it might lead to a destablisation of the rest of the ice sheet and ice shelves around it. And we also know that it is changing one of the quickest.”

[Wing of aeroplane]

[Plane flying overhead]

[Ice sheets]

[Shot from beneath an aeroplane]

[Ice sheets]

[Satellite graphic showing ice sheet changes at Thwaites from 2016-2022]

[Time lapse video of mountains in Antarctica]

[Ice cores kept in storage]

[Ice sample in hand]

Dr. Liz Thomas (interview): “The long and deep ice cores are fantastic at showing us these really big glacial changes where we could say there’s been similar high green house gasses in the past but actually it’s the rate of change that’s so important, those kind of timescales take thousands of years for ice sheets to change and evolve, what we’re seeing now is since this great acceleration during the 20th Century, these are things that are happening at a rate we have never seen in our recent history.”

[Ice sheets in Antarctica]

This script was provided by The Associated Press.

The related lesson for this video will be published next Wednesday.