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Research: Nearly a quarter of the ice in the West Antarctica is unstable.

By combining 25 years of European Space Agency satellite altimetry with local climate models, the UK Polar Observing and Modeling Center (CPOM) has tracked changes in the snow and ice of the continent.

Professor Andy Shepherd of the University of Leeds has thinned the ice sheet of Antarctica to 122 meters, and the most dramatic change in the Antarctic Atlantic has triggered a glacier imbalance.

That is, affected glaciers are unstable because they lose more mass through melting and iceberg fission than snowfall.

The researchers found that the pattern of glacial dilution was not static. Since 1992, 24% of West Antarctica, and the thinning of the largest ice streams, Pine Island and Thwaites Glaciers, are losing ice five times faster than the current survey.

This study, published today, Geophysical Research LettersUsing more than 800 million measurements of the Antarctic ice sheet height recorded by the ERS-1, ERS-2, Envisat and CryoSat-2 satellite altimeter missions from 1992 to 2017 and using the same period heavy snow simulations generated by the RACMO regional climate The model.

With these measurements, changes in ice sheet height can be separated by weather patterns such as snowfall reduction and long-term changes in climate, such as rising sea water temperature to throw away ice.

Professor Andy Shepherd explains, "In Antarctica, we started to show the effects of climate change and climate change because the ice sheet is extremely thin."

To do this, the team compared the measured elevation changes to snowfall changes, and where discrepancies were greater, the origin was due to ice age imbalance.

They found that changes in snowfall tend to lead to small changes in height in large areas over several years at a time. However, the most noticeable change in ice thickness is the signal of a glacial imbalance that has lasted for decades.

Professor Shepherd added: "Knowing how much snow has really helped to detect the fundamental changes in glacier ice in the satellite record, we can clearly see that a thinning wave has spread rapidly over some of the most vulnerable glaciers in Antarctica, The loss of sea level around the earth is rising.

"East and South Pole ice loss has contributed 4.6 mm to global global sea level rise since 1992.

Dr. Marcus Engdahl, co-author of the study, European Space Agency, added: "This is an important demonstration of how satellite missions can help us understand how our planet is changing: polar regions are hostile and extremely difficult to access from the ground, It is an essential tool for tracking. "

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