Record melting for the most unstable glaciers in the South Pole
The melting of the two glaciers will raise the global seas by 3.4 meters over several centuries
(Sustainabilityenvironment.com)- The rocks of the glaciers of Antarctica are happening at a pace that has never been seen before in the last 5500 years. Let’s talk about the Thwaites and Pine Island glaciers, already the focus of many studies in recent years that have tried to estimate the probability of collapse and the impact on sea level rise. A new study by Imperial College London reconstructs the behavior of the two glacial masses in the last millennia and confirms the alarm of the scientific community.
Just after the mid-Olocene climatic optimum (around 9-5000 years ago), when the global temperature was higher than today and these two glaciers retreated, the two glacial masses maintained a behavior that scientists define as stable. This is what emerges from the analysis of the relative change in the height of the water level in front of the points where glaciers enter the sea.
Using radiocarbon analysis on penguin bones and shells, the London University team was able to accurately date when certain stretches of coastline emerged as a result of melting glaciers (the ground, no longer crushed, tends to rise and compensates locally for the lifting of water). The succession of dates becomes a chronicle of the dissolution from which we can derive the speed with which it happened.
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And here study reaches the most important result. Compared to today, the relative rate of sea-level change between 9000 and 5000 years ago was 5 times slower. In other words: Thwaites and Pine Island today are interesting in the very rapid melting of the ice.
“We have revealed that, although these vulnerable glaciers were relatively stable over the past millennia, their current retreat rate is accelerating and already raising global sea levels,” explains Dylan Rood, co-author of the study. “These currently high rates of ice melting can signal that the vital arteries of the heart of the West Antarctic Ice Sheet [Thwaites and Pine Island, ed] have broken, causing an acceleration of flow in the ocean, potentially disastrous for the future global sea level in a warming world”. Is it too late to stop the bleeding?”.