قالب وردپرس درنا توس
Home / Science / First confirmation of the tipping point of Antarctic glaciers

First confirmation of the tipping point of Antarctic glaciers



First confirmation of the tipping point of Antarctic glaciers

Dr. Sebastian Rosier in the Pine Island Glacier in 2015.

Researchers have confirmed for the first time that the Songdo Glacier in western Antarctica may cross the tipping point, causing a rapid and irreversible retreat, which will have a significant impact on global sea levels.

Pine Island Glacier is an area of ​​fast drifting ice, and its loss is about two-thirds of the United Kingdom. The glacier is a cause of special concern because it loses more ice than any other glacier in Antarctica.

At present, Songdo Glacier and its neighboring Thwaites Glacier account for about 1

0% of the continuous global sea level rise.

Scientists have argued for some time that this part of Antarctica may reach a tipping point and experience an irreversible retreat that cannot be restored. Once such a retreat begins, it may cause the entire West Antarctic ice sheet to collapse, which contains enough ice to raise the global sea level by more than three meters.

Although the general possibility of such a tipping point in the ice sheet has been proposed before, it is a very different problem to show that the Pine Island glacier may enter an unstable retreat.

Now, researchers at Northumbria University have shown for the first time that this is indeed the case.

Their findings were published in the leading journal ” Cryosphere.

The team used the latest ice flow model developed by the Northumbria Glaciology Research Group to develop a method that can identify critical points in the ice sheet.

For the Pine Island glacier, their research shows that the glacier has at least three different critical points. The third and final event was caused by an increase in ocean temperature of 1.2 degrees Celsius, which caused the entire glacier to retreat irreversibly.

First confirmation of the tipping point of Antarctic glaciers

Songdo Glacier.Image credit: Dr. Sebastian Rosier

Researchers say that long-term warming and shoal trends in extremely deep waters, coupled with changing wind patterns in the Amundsen Sea, may expose the ice shelves of the Pine Island Glacier to warmer waters for extended periods of time, thereby causing This degree of temperature change is becoming more and more possible.

The lead author of the study, Dr. Sebastian Rosier (Sebastian Rosier), is the vice-principal researcher of the Northumbria Department of Geography and Environmental Sciences. He specializes in the modeling process that controls the Antarctic ice flow, aiming to understand how the continent will contribute to future sea level rise.

Dr. Rosier is a member of the University’s Glaciology Research Group, which is led by Professor Hilma Goodmondson. The group is currently conducting a large £4 million study to study whether climate change will push the Antarctic ice sheet to reach critical point.

Dr. Rosier explained: “In the past, the area may have crossed critical points, but our research confirmed for the first time that Songdo Glacier did indeed cross these critical thresholds.

“Many different computer simulations around the world try to quantify how climate change affects the West Antarctic ice sheet, but it is challenging to determine whether the recession period in these models is a critical point.

“However, this is a crucial issue, and the methods we use in this new study make it much easier to determine potential future tipping points.”

Hilmar Gudmundsson, professor of glaciology and extreme environment, conducted this research in collaboration with Dr. Rosier. He added: “The possibility of Songdo Glacier entering an unstable retreat has been raised before, but this is the first time that this possibility has been rigorously determined and quantified.

He said: “This is an important step in our understanding of the dynamics in this field. I am glad that we are now finally able to provide a firm answer to this important question.

“But the findings of this study also worry me. If the glacier enters an unstable and irreversible retreat, the impact on sea level can be measured in meters, and as the study shows, once the retreat begins, It is impossible to stop it.”

You can now view the article “Tip Point and Early Warning Indicators of Songdo Glacier in Western Antarctica” at the following location. Cryosphere.


New research reveals when Antarctica’s largest glacier began to retreat


More information:
Sebastian HR Rosier, etc., the critical point and early warning indicators of Songdo Glacier in western Antarctica, Cryosphere (2021). DOI: 10.5194/tc-15-1501-2021

Courtesy of Northumbria University



Citation: The evidence for the tipping point of Antarctic glaciers retrieved from https://phys.org/news/2021-04-evidence-antarctic-glacier.html on April 2, 2021 (April 2, 2021) was confirmed for the first time.

This document is protected by copyright. Except for any fair transactions for private learning or research purposes, no content may be copied without written permission. The content is for reference only.




Source link