Slumping Ice Cliffs can trigger a rapid rise in sea level


A new study showed that ice cliffs could break through in a process called "slumping" and could lead to a rapid rise in sea level. High ice scales are more likely to be susceptible to falling, scientists said. ( Byron Parizek and his colleagues )

Ice caves melt and flow into the ocean during a process called calving, but scientists in Greenland believe that another process could cause a rapid rise in sea level.

A group of researchers crossing the Helheim and Jakobshavn glaciers on the eastern coast of Greenland found in a new study that a process called slumping could break much larger parts of ice faster. The consequences of this process can be large.

Richard Alley, one of the co-authors of the new study, published in the magazine Geology, said that if it happened in Helheim in the Antarctic over the next hundred years, the models suggest that the rapid rise of sea level could exceed the already predicted.

What is falling?

Glaciers that discharge ice sheets often end up with almost vertical walls. When the glacier moves into the sea, the pieces break off.

Such gymnastic events often occur when the sea melts before ice and the ice cave falls. But Alley and his colleagues found that a large mass is not needed to dissolve and flow into the ocean because it requires some solid. That's what it's descending.

Helheim Helicopters suddenly end up in the ocean in ice walls at least 100 meters high. In recent years, scientists have seen large cracks, called ice cracks Helheim, which went towards the end of the glacier.

Alley explained that falls occur when the mass of the sediment or stone loses its power, it moves away from the ground and descends along the slope. The fall is usually marked with a string where the material decays, followed by a material that has moved downwards.

The characteristics of the Helheim glacier are usually those that can be found in an area that is prone to falling. For this reason, Alley and his colleagues ask scientists whether the ice will experience the same fate. He explained that in the ice there was a scar, followed by stress in the ice, which is the largest on the water surface.

How to get down in the Arctic

Alley says that geologists have been worrying about falls for decades. He and his team decided to test whether the fall that accompanies the Helheim glacier among the females really noticed on the ice walls. They measured the position, speed and movement of the ice.

They saw that a strong acceleration of ice flow before the fall began, and then the thickness of the melting glacier was spinning. The remaining ice sheet revolves and reaches both the sea and below it.

Alley and his colleagues realized that falling from high cliffs reaching 100 meters of ice above water. Regular calving usually happens very slowly because the ice melts. On the other hand, the decline occurs without waiting for the ice to come up, researchers found.

"We will go down … basal cracks … boom," Alley said.

In some places in Antarctica you can find a glacier bed at least 2000 meters above the sea level, creating a much larger ice cliff. Alley said he worries that higher cliffs are more susceptible to falling. If there is a fall in Antarctica, this may lead to a rising sea level rise.

Meanwhile, Alley and his team are preparing for further investigations in the future. He said that they still want to understand the fracture of the ice and how it relates to it. They plan to collect more observational data to improve their models.

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