Deep beneath Antarctica’s frigid surface, researchers have detected “alarming” changes.
It’s long been known that melting ice sheets are causing sea levels to rise, but researchers have now discovered a previously unknown phenomenon that could be accelerating this process.
This problem could directly affect the 900 million people who live in low-lying coastal cities around the world, so efforts to protect these towns from coastal flooding may need to be deployed more quickly than previously thought.
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How could this “worrying” new melting occur?
The British Antarctic Survey (BAS) discovered that the problem occurs where land-based ice sheets meet the ocean. Known as “grounding zones,” these areas typically span several kilometers and are known to be sensitive to changes in the atmosphere and oceans.
Here, climate change is making ocean waters increasingly warm, accelerating the formation of new cavities in the ice. These holes allow more water to flow from the ocean into the space between the ice and the ground above it. This lubricates the ice sheet and speeds up the rate at which it melts into the ocean.
“Very small changes in ocean temperatures can greatly increase melting of the ice sheet and lead to major changes in how the ice flows over it,” said Alex Bradley, an ice dynamics researcher at BAS.
Further alarming changes in Antarctica
Sea level rise projections may be underestimated
Changes in the region are causing huge amounts of water to flow into the ocean and cause sea levels to rise, and BAS said the discovery represents a “worrisome new way” that large ice sheets are melting.
Bradley worries that the impacts of warming oceans on the Antarctic and Greenland ice sheets have not yet been taken into account in Intergovernmental Panel on Climate Change (IPCC) climate models.
“Our projections for sea level rise are likely significantly underestimated,” he warned.
The findings were published in the journal. Nature Chemistry.
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