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New island revealed after the ice melts

Scientists discovered a newly revealed object that looks like an island in Antarctica, about 30-35 m high above sea level.

An island-like object exposed in East Antarctica in images taken by the Landsat satellite in 1989, 2001 and 2022. Photo: NASA

An island-like object exposed in East Antarctica in images taken by the Landsat satellite in 1989, 2001 and 2022. Photo: NASA

The east coast of Antarctica has lost much of the Glenzer and Conger ice shelves, but the process may have left an island exposed, SciTechDaily reported on 7/5. If confirmed, it would be one of many islands exposed in recent years as glaciers around the Antarctic coast have disintegrated.

The new object has not yet been named. It can be seen in a trio of images taken by the Landsat satellite from 1989 to 2022. It remained in shape after the shelf ice split and the surrounding sea ice melted. The white mass did not budge even though large icebergs may have crashed into it after the rapid collapse of the Glenzer and Conger ice shelves earlier this year.

The new object also appears to be taller than the surrounding area. At least part of it is 30-35 meters above sea level, according to data collected by NASA’s ICESat-2 satellite on December 22, 2021. This may not, however, be a solid jutting mass of land in the traditional sense of the island.

This feature could be an ice island – a large, heavy ice cap that sits firmly on an underwater mountaintop, said John Gibson, a scientist at the Australian Department of Agriculture, Water and Environment’s Antarctic Unit. “It’s really similar to other ice islands, like Bowman Island, for example,” Gibson said.

Gibson calls it a “self-sustaining” ice island, meaning that the snow and ice that accumulates on the island’s surface is equal to the amount that melts underwater. If that balance is disrupted due to reduced snowfall, the island can thin and drift away. “The unknown island is a permanent feature of the landscape, but one day it could break away from the rock below and become an iceberg,” Gibson said.

The structure of the island is still a mystery. “To be sure, you need to bring a ship to the edge of the island to check the bedrock, even put radar on it to assess the thickness of the ice. ICESat-2 data shows that the island’s surface is high above the sea level. This means there must be a lot of ‘ice cream’ on the ‘cone shell’ if there is no bedrock at or above sea level,” said Christopher Shuman, glaciologist at the Center for the Flight. NASA’s Goddard Space Station, explains.

The new island adds to the list of similar objects that are no longer in the Antarctic ice sheet. In 2019, the U.S. Commission on Places recognized Icebreaker Island, which split from the Larsen B Ice Shelf along the Antarctic Peninsula in 1996. In 2020, researchers discovered a small ice-covered island that may have once belonged to the Antarctic Peninsula. the ice shelf of the Pine Island Glacier.

“The discovery of more such objects is likely to continue in the coming years as glaciers and sea ice are shrinking. These are objects that are new to us, but now we also have many cores. more force and tools to observe the Antarctic fringes. Some examples are not trending, but they suggest that other once-hidden objects may be revealed in the coming years,” Shuman said.

Thu Thao (According to SciTechDaily)

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