‘Disturbing’ discovery under Antarctic ice sheets

Researchers have discovered a “worrying” change deep beneath the surface of the frigid Antarctic continent.

While it has long been known that melting ice caps are causing sea levels to rise, researchers have discovered a previously unknown event that may be accelerating the process.

This problem could directly affect 900 million people living in low-lying coastal cities around the world, so efforts to protect these cities from coastal flooding may need to be made faster than previously anticipated.

Related: An ice shelf the size of half Canberra is breaking off from Antarctica

How is this “alarming” new melting happening?

The British Antarctic Survey has found that the problem occurs in areas where land-based ice sheets meet the sea. These areas, known as “convergence zones,” are typically several kilometres long and are known to be sensitive to weather and ocean changes.

Here, increasingly warm sea water due to climate change is speeding up the formation of new holes in the ice. These holes allow more water to flow from the sea into the space between the ice and the ground it rests on. This lubricates the ice layer above and speeds up the rate at which it melts back into the sea.

“A very small change in ocean temperature can cause a very large increase in melting of the impact zone, which would lead to a very large change in the flow of ice over it,” said Alex Bradley, a researcher in ice dynamics at the British Temperature Survey.

More disturbing changes in Antarctica

Predictions of sea level rise can be an underestimate

Changes in this area are responsible for a lot of water entering the ocean and causing sea levels to rise. BAS says the discovery demonstrates a “new and worrying way” in which large ice sheets are melting.

Bradley expressed concern that the impact of warming waters on anchoring areas in both Antarctica and Greenland has not yet been taken into account in climate models prepared by the Intergovernmental Panel on Climate Change (IPCC).

“Our expectations about sea level rise may be far underestimates,” he warned.

The results were published in the journal Natural Earth Sciences.

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