The largest ice shelf in the world melts 10 times faster than expected when the waters warm up

The world's largest ice shelf melts 10 times faster than expected due to solar warming in the surrounding Antarctic Ocean, scientists warned.

The Ross ice floe covers an area about the size of France and is several hundred meters thick, with 90% of the ice lying below sea level.

A study conducted by an international team of scientists over four years has collected data on the interaction of the northwestern part of the pack ice with the ocean below.

He found that the ice melts much faster than we thought, because of the influx of hot water.

"Ice shelf stability is generally thought to be related to their exposure to the warmth of deep ocean waters, but we have found that sun-heated surface waters also play a crucial role in melting. ice platforms, "said Dr. Craig, lead author of the study. Stewart of the National Institute for Water and Atmosphere Research (NIWA) in New Zealand, who led the work while he was a PhD student at the University of Cambridge in the United Kingdom.

The interactions between ice and the ocean hundreds of meters below the surface of the ice platforms have a direct impact on the sea level in the long term.

The Ross ice floe is a vital natural barrier that stabilizes the West Antarctic Ice Sheet by blocking ice from the world's largest glaciers.

"Previous studies have shown that when ice plateaus collapse, feeding glaciers can be multiplied by two or three," said co-author Dr. Poul Christoffersen of the Scott Polar Research Institute in Cambridge.

"The difference here is in the sheer size of Ross' ice floe, which is a hundred times larger than the pack ice we've seen disappear."

If the entire West Antarctic Ice Sheet melted, it was estimated that the enormous volume of water released would contribute up to 4.8 m in the world's seas.

The team collected data from an oceanographic mooring under Ross ice floes by members of the NIWA team.

Using instruments laid in a 260-meter deep borehole, the team measured temperature, salinity, melting rates, and ocean currents in the ice cavity.

The anchorage instruments showed that sun-heated surface water penetrated the cavity under the ice near Ross Island, resulting in a near-three-fold increase in the melting rate during the winter months. summer months.

Directly in front of the ice, there is free water. The region, known as the Ross Sea polynya, quickly absorbs solar heat in summer and this warmer water influences melting in the ice floe cavity, scientists said.

The results indicate that conditions in the pack ice cavity are more closely related to the surface of the ocean and the atmosphere than previously assumed. It also implies that melting rates near the ice front will react quickly to changes in the warmer upper layer of water in the ocean.

"Climate change is likely to result in a decrease in sea ice and an increase in ocean surface temperature in the Ross Sea, suggesting that melting rates in this region will increase in the future", said Dr. Stewart.

Dr. Christoffersen added: "The observations we made at the front of the pack ice have direct consequences for many large glaciers flowing into the pack ice, some up to 900 km."