We will say it bluntly. A bird's eye view of the ice shelf ofPine islandIn Antarctica, it is a train heading towards the wreck in slow motion. Of course from a human perspective. In geological time everything is happening in the blink of an eye.
It has been more than 3 decades sinceUniversity of California and the Jet Propulsion Laboratory –JPL for its acronym in English-POT, it has been reported that West Antarctica has begun to melt. Now, the gigantic block that is about to separate from the ice shelf, known asLarsen C, may be the precursor to a collapse of the entire continent, which, if it occurred, would flood a large number of coastal cities around the world.
Little by little the edges of Larsen C crumble as easily as the walls of a sand castle. On its surface, scarred, large cracks are scattered that compete for space with thaw lagoons of up to 400 square meters.
In recent decades the waters of the Amundsen Sea, also in the western part of Antarctica, have warmed more than 0.5ºC, and in this time, the rate at which the ice is melting and fracturing has quadrupled. Already between 2015 and 2016 a block of about 360 square kilometers broke away, moving away from the coast of the same sea.
However, at present the predictions for the increase in temperature, in this case for theweddell sea adjacent to Larsen C, they average 5ºC. This is the reason why many smaller ice shelves have already completely succumbed. And also the reason and why Larsen C is about to become an ice shelf that will drift through theAntartic Ocean until they merge in communion with its waters.
The crack in Larsen C is almost 200 kilometers long and in some of its parts the width can reach 2,000 meters.In its expansion, when it reaches the end, it will give rise to one of the largest icebergs ever recorded, of about 5,000 square kilometers, that is, almost the surface of the Autonomous Community of Cantabria.
According to himMidas Project,developed by a joint research team of theSwansea Universities YAberystwyth, and through which the crack has been monitored since 2014, due to the stress generated by the crack, the iceberg separation is expected to occur very soon.
The professor of the UUniversity of California and scientist NASA,Eric J. Rignot, states that the recent twist of the crack evidences its early fracture. "In my experience, when the gap takes a 90 degree turn, as is the case, the fracture is just around the corner. It is a matter of weeks."
At first glance the fracture and detachment of this section of Larsen C can be seen as a symptom of the warming experienced in recent years. Perhaps an event of little significance, since in this period we have witnessed larger glaciers.
However, the importance of this fracture lies in the fact that the ice that is about to break off is settled on a series of islands. On the contrary, the vast majority of the rest of the platform rests on a basin that goes deep up to 5,000 kilometers, which makes it especially vulnerable to rising ocean temperatures. It is at this point where the situation becomes complicated, then, if the disarmament and breaking into smaller and smaller pieces of such a quantity of ice occurs, and above all, as scientists believe, at an ever-increasing speed, the Sea level would rise by more than three meters flooding entire cities around the world.
Thus the melting of the Pine Island ice shelf is a dramatic case. With an average thickness of 400 meters, between 1994 and 2015 the amount of ice has been reduced by 10%. The most worrying thing is that the withdrawal of ice from the Larsen C platform could affect the neighborThwaites glacier, which would be susceptible to destabilizing most of West Antarctica.
"Now these glaciers are disappearing faster and faster from the Earth's surface," says Rignot, who has been studying the region for more than two decades using airplanes and satellites. The scientist is convinced that the collapse of the western Antarctic ice sheet is inevitable. “It is just a matter of time. The important thing is to know if this will happen in a period of 500 years, or in less than 100. And above all, if humanity will be fast enough to prepare for events. "We have to clear up the unknown," says the researcher, and we must do it before it is too late. "
The Larsen C platform is just a little warning.