Under the West Antarctic Ice

As the Antarctic ice melts, large chunks break off, forming huge ice bergs that float out to sea and wander for years.  This process is normal, though we may be seeing more and faster calving, as the ocean and air warms up.

This year, a new iceberg, tagged A74, finally separated from the ice in the Weddell Sea.  This process was observed rather closely, not least by the British Antarctic Survey, which relocated a base that was near the developing crack.

Also in the area was the German research ship, Polarstern, run by the Alfred Wegener Institute.  The German team was able to sail into the gap between the new berg and the ice sheet, and to deploy a submersible vessel to image the sea bottom. The reconnaissance yielded images of many animals [1].

The ecology revealed is similar to what might be seen in shallow cold oceans anywhere, but this location has been under the ice, tens of kilometers from open ocean, for at least the last fifty years.  So, this observation shows that there can be quite a bit of life under the ice.

The researchers hope to return to the site in the future to document the changes to the ecology after the berg separates.

This region of East Antarctica is interesting because it has not experienced the warming seas that West Antarctica has seen.  Not yet, at least.

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1. Jonathan Amos, Antarctic seafloor exposed after 50 years of ice cover, in BBC News – Science & Environment, March 18, 2021. https://www.bbc.com/news/science-environment-56424338