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Worsening rifts and fractures spotted at two of Antarctica’s most important glaciers

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Worsening rifts and fractures spotted at two of Antarctica’s most important glaciers
Satellite imagery has revealed that two of the fastest-changing glaciers in Antarctica are fracturing and weakening faster than ever – the first step towards the glaciers disintegrating and causing sea levels to rise dramatically. Credit: Pixabay/zhrenming

Satellite imagery has revealed that two of the fastest-changing glaciers in Antarctica are fracturing and weakening faster than ever—the first step towards the glaciers disintegrating and causing sea levels to rise dramatically.


Using observations from ESA, NASA and USGS satellites, the researchers explored the Pine Island and Thwaites Glaciers in the Amundsen Sea Embayment: two of the most dynamic glaciers on the Antarctic continent, and those responsible for a substantial 5% of global sea level rise.

Together, the two glaciers form an area of flowing ice the size of Norway, and hold enough water to raise global sea levels by over a meter. Both have distinctly changed in morphology in recent decades along with changing atmospheric and oceanic conditions, with the warming oceans causing ice shelves to melt, thin, and retreat.

Predicting how these vital glaciers will evolve in coming years is critical to understand the future of our seas and our warming planet—but such predictions have remained uncertain, with computer models unable to fully account for the glaciers’ processes and properties in their projections.

“To reveal what’s really going on at Pine Island and Thwaites, we dug into imaging data from a number of different satellites,” says Stef Lhermitte of Delft University of Technology in the Netherlands, and lead author of the new study.

The evolution of damage to the Pine Island (boxes P1 and P2) and Thwaites (T1) Glaciers from October 2014 to July 2020, as seen by the Copernicus Sentinel-1 mission. The ice sheets of both glaciers can be seen fracturing and tearing apart. Credit: contains modified Copernicus Sentinel data (2014-20),

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Salty lakes below Mars’ glaciers could harbor life

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Scientists have detected a series of saltwater lakes beneath the glaciers of Mars’ southern ice cap. The researchers think the liquid in these lakes doesn’t freeze and become solid, despite the low temperatures of Mars’ glaciers, due to its extremely high concentrations of salt.

The Mars Express spacecraft, which has been surveying the red planet since 2005, had previously detected signs of a subglacial lake basin on Mars’ south pole, but it was unclear whether the lake was liquid or what it contained.

mars ice cap south pole southern

The southern ice cap of Mars, April 17, 2000.


NASA/JPL



To find out, a group of Italian, German, and Australian researchers applied a radio-echo technique that Earth satellites use to detect subsurface lakes in Antarctica. They scanned the area multiple times from 2010 to 2019, then published their results in the journal Nature Astronomy on Monday.

The analysis confirmed the liquid-water nature of Mars’ underground lake, as well as its extreme saltiness.

Elena Pettinelli, a professor of geophysics at Italy’s Roma Tre University who led the study, told NBC News that scientists are “much more confident now” that these Martian lakes exist.

“We did many more observations, and we processed the data completely differently,” Pettinelli added.

What’s more, the researchers also found “a more extensive, complex scenario with ubiquitous water patches surrounding the subglacial lake,” according to the study.

The discovery offers yet another possible habitat for life to persist on Mars.

Ancient life may have retreated to underground lakes on Mars

Scientists think the Martian surface was once rich with rivers, lakes, and seas, but all the surface water evaporated as a flow of particles from the sun stripped away the planet’s atmosphere. Earth’s strong magnetic field, by contrast, has allowed it to hold onto its atmosphere and its surface water.

mars surface river channels water

The southern section of the