Researchers from the United States showed that the cause of the destruction of the Antarctician shelf glaciers is the thinning of the so-called ice melanges – the mixture of iceberg debris, apparent snow and frozen water. The article of scientists has been published in the journal Proceedings of the National Academy of Sciences.
Using the information models developed in the Agency, obtained during the ICEBRIDGE operation (polar glacier monitoring programs) and satellite data, the researchers analyzed which of the faults in the Larsen Glacier at most likely will lead to the formation of a new iceberg. They chose 11 of them, who led the A68 in 2017 – at that time of the largest iceberg in the world – and modeled for each three scenario: thinning of the glacier due to melting, the thinning of the ice melange and the option where these factors are combined.
It turned out that the first scenario led to a decrease in faults – the average annual expansion of their expansion fell from 79 to 22 meters. The third scenario also slowed down the increase in faults, albeit at least. However, the thinning of the ice melange led to the fact that the average annual increase in faults in the glacier grew from 76 to 112 meters threatening.
Researchers note that this phenomenon allows you to make much better explaining the retreat and destruction of the Antarctician shelf glaciers recently than the models built on the mechanism of hydraulic. “When the thickness of the melange reaches only 10-15 meters, it becomes akin to water, and faults in the shelf glaciers begin to grow,” – notes the lead author of the study, researchers of the NASA Motion Laboratory of NASA Eric Larour. Melt melange warm water from the oceans, explain scientists.