According to a new study, the two main glaciers that make up the Antarctic ice sheet are melting faster than in the past 5500 years. Ironically, this conclusion is based on the fact that the sea level in the region seems to decline over time. It is reported that the research was jointly carried out by scientists from the University of Maine and the British Antarctic Survey.
The study involved radiocarbonization of shells and Penguin bones found on beaches near today's Thwaites and Pine Island glaciers. Given the current melting rate of these two glaciers, it is speculated that the global sea level may rise by 3.4 meters in the next few centuries.
That is to say, 5500 years ago, the much slower melting process actually led to the decline of relative sea level in the region. This is due to the fact that when a heavy glacier lies on the earth, its weight compresses the land downward. As the glacier melts and lightens, the land under it will bounce back accordingly.
As a result, beaches near glaciers that were initially at sea level gradually moved upward and were replaced by new beaches below
By determining the age of the shells and bones of each beach layer, scientists were able to determine the rate at which the land moved upward, and thus the rate at which the glaciers melted. Although this rate remained slow and stable for almost all periods of 5500, it is said that in modern times, this rate has increased fivefold due to global warming.
Dr Dylan rood, from Imperial College London, pointed out: "these currently rising melting rates of ice and snow may indicate that those important arteries from the heart of the Antarctic ice sheet have burst and accelerated their flow into the sea, which may be disastrous for the future global sea level in a warming world." It is reported that Imperial College London is subordinate to the British Antarctic Survey.
Scientists are now planning to drill into the glacier to collect rock samples under the glacier, which may provide clues as to whether the current rate of accelerated melting can be reversed.