How is the giant iceberg that falls in Antarctica

Countdown to the birth of a new giant iceberg in the

Antarctic

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The cracks observed on the floating pack ice known as Brunt leave no doubt. It will not be long before an iceberg of an area twice as large as New York City comes off the ice mbad towards the Weddell Sea.

The crack in the pack ice is near the
British research base Halley, who in 2017 had to move to escape the danger. It is not clear when the separation will take place, but it seems imminent.

Therefore, as a precautionary measure, British Antarctic Prospecting (BAS) has decided to withdraw its staff from Halley Station.

The crack in the pack ice is near the British research base Halley, which had to move in 2017 to get away from danger. It is not clear when the separation will take place, but it seems imminent

The influence of climate change

As soon as the detachment takes place, one of the first questions we will ask ourselves is: what influence has climate change had on the creation of the iceberg?

And one
The Northumbria University team that followed the case says it will be able to respond with confidence: "None".

Scientists Jan De Rydt and Hilmar Gudmundsson spent years studying the region and ensured that the event was solely due to natural processes. These two experts constructed a model to describe the behavior of the Brunt Sea Ice.

This platform is essentially an amalgam of glacial ice that sank from the ground and entered the sea at a speed of about 400 meters per year.

Using satellite and surface data, the team model reveals the distribution of tension on the platform, between 150 and 250 meters thick.

The Brunt Floe is an amalgam of glacial ice that sank from the ground and entered the sea at a speed of about 400 meters per year.

And he accurately predicts where the cracks are likely to develop and what their path is.

"The work shows that the crack started to widen because of the tension that has accumulated due to the natural growth of the pack ice, and the pack ice itself has created this crack," says Professor Gudmundsson.

The Brunt Sea Ice has never been so advanced. Since the famous explorer Ernest Shackleton inspected it in 1915, the edge of the platform has stopped progressing.

Thus, the cracking of the iceberg seems close.

"No oceanographic or atmospheric data indicate that the climate is changing in the Brunt area," De Rydt said.

"Our ocean observations are limited, but the data we have at hand do not indicate anything unusual, and our model shows that what we see can be perfectly explained by the natural changes in the geometry of the ocean. pack ice, "he added.

Scientists from Northumbria have already worked on the British Antarctic Survey. It is their badysis that confirmed the decision to relocate Halley Station and the choice of location: 23 km above the crack.

If he had not moved, the base would now be in a very precarious position.

The possible consequences

There is some uncertainty as to the exact response of the platform to the large detachment and the British Antarctic Prospecting wants to avoid having to organize rescue missions in the dark of a polar winter, which would be extremely dangerous. That's why he ordered the closure of the base between March and November.

Without anyone on the ground, the notification of any breakage must come from the instruments in place.

The EU's Sentinel-1 satellites fly over the area every two or three days and their precise measurements make it possible to discern not only the propagation of cracks, but also the subtle deformation of the ice during its movements.

Although the scientific model can predict the crack behavior of the Brunt pack ice, it can not predict the exact timing of the fallout.

There remains about 3 to 4 kilometers of the fissure that forms the possible 1,500 square kilometer iceberg before cutting off Brunt's platform completely.

In the absence of this last section, the iceberg could be a reality tomorrow or several months might be needed.

"Extrapolation is perhaps the easiest way to calculate it," says Professor Gudmundsson.

He adds: "The crack was growing about 1 to 2 km a year and we did not see any deceleration in winter, it's almost done, but I would say that the new iceberg will be born in a year."