Scientists working in Antarctica have recorded, for the first time, unusually warm water under a glacier the size of Florida that is already melting and sea level rising.
The researchers, working on Thwaites Glacier, recorded water temperatures at the base of the ice of more than 2 degrees Celsius above normal freezing point. Worryingly, the measurements were taken at the glacier’s landline, the area where it goes from resting on bedrock to extending into the sea as ice shelves.
It is not clear how fast the glacier is weakening : Some studies have predicted its total collapse within a century and others within a few decades. The presence of warm water at the land line can confirm estimates to the shorter range.
This is important because Thwaites, along with Pine Island Glacier and a number of other smaller glaciers, acts as a brake on part of the much larger West Antarctic Ice Sheet. Together, the two largest glaciers are currently holding ice that, if it were to melt, would raise the world’s oceans by more than a meter, an amount of water that would leave many coastal cities underwater.
The warm waters of this part of the world, as remote as they may seem, should serve as a warning to all of us about the possible and serious effects of climate change on the planet.
David Holland, principal investigator of the expedition and director of the Environmental Fluid Dynamics Laboratory at New York University.
Scientists have previously warned of the presence of hot water melting the Thwaites from below. This is the first time, however, that warm waters have been measured at the glacier’s land line.
To study the activity under the glacier, Dr. Holland’s team drilled a hole about 30 cm wide and 600 m deep. The results of the study are expected to be published in March. The expedition was part of the International Thwaites Glacier Collaboration.
While scientists can’t yet predict exactly when glaciers like Thwaites will melt, man-made climate change is a key factor.
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