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Realitarakyat.com – Scientists at NASA announced that they have discovered two new lakes buried under the Antarctic Ice Sheet. The lakes found under 1.5 miles of ice form part of an extensive network of underground waterways.
These lakes are said to continue to fill and flow in mysterious cycles that can affect how fast the ice sheet moves and how and where meltwater reaches the Southern Ocean – a key process for global ocean circulation.
Study leader Professor Matthew Siegfried, a geophysicist at the Colorado School of Mines, said this was not just an ordinary ice sheet. “This is a water system that is connected to the entire Earth system,” he said as quoted by Express.co.uk, Sunday (18/7/2021).
This water system at the bottom of the ice sheet was first discovered with the help of NASA’s ICESat mission
in 2003. After analyzing the data, scientists found that variations in ice height in West Antarctica reflect the large masses of subglacial water movement beneath the ice sheet.
Previously it was believed that hidden meltwater lakes existed in isolation, cut off from each other. But in 2007, researchers discovered that fluctuations in Antarctic ice surface height signaled the movement of water flowing between a network of hidden subglacial lakes, which alternately filled and drained water before it flowed into the Southern Ocean.
Now, ICESat’s follow-up mission – ICESat-2 – is giving scientists a clearer understanding of the mysterious network.
Prof Siegfried explained that the discovery of this interconnected lake system at the interface of the ice sheets that move the water, with all the impacts on glaciology, microbiology and oceanography – it was a major discovery of the ICESat mission.
“ICESat-2 is like putting on your glasses after using ICESat, the data is so precise that we can actually start to map the boundaries of lakes on the surface,” he said.
The team’s new study collected data from ICESat-2 and the original ICESat mission, along with measurements taken from CryoSat-2, an ice-watching satellite operated by the European Space Agency (ESA).
By studying data ranging from 2003 to 2020, the researchers were able to monitor active subglacial lakes.
“This system is hidden beneath up to 2.5 miles of ice and remains one of the main physical uncertainties in projecting future ice sheet dynamics,” the researchers wrote.
“ICESat-2 laser altimetry can not only extend the record of subglacial lake activity, but also provide a better understanding of hydrological processes by capturing denser and more precise spatial detail.” (Din)
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