In the northwest of Antarctica, an iceberg with an area of almost 6,000 square meters broke off from the Larsen C ice shelf. km and weighing a trillion tons - one of the largest in the history of observations, reports the BBC.
— Project MIDAS (@MIDASOnIce) July 12, 2017
— Amichai Stein (@AmichaiStein1) July 12, 2017
The thickness of the Larsen Glacier reaches approximately 350 meters. It keeps all the internal glaciers of Antarctica from descending into the ocean, which may also begin to separate from the continent. The detachment of the iceberg led to the loss of a tenth of the entire glacier.
Iceberg formation is not related to global warming. Unlike thin layers sea ice, Larsen is an ice shelf, that is, a mass of ice floating in the ocean.
"There's enough ice in Antarctica to raise sea levels by 60 meters if everything melts or even just spills into the ocean," Imperial College London geology professor and co-director of the Grantham Climate Change and Climate Change Institute told The Guardian. environment Martin Siegert.
The birth of a huge iceberg will not lead to a rise in the level of the world ocean. "It's like an ice cube in your gin and tonic glass - it's already floating, and if it melts, it doesn't change the volume of water in the glass very much," Siegert compared.
According to scientists, in the near future the iceberg will move rather slowly, but it must be observed: sea currents can take it to a place where it will be a danger to the movement of ships.
Larsen Glacier originally consisted of three - Larsen A, Larsen B and Larsen C. Over the past half century, temperatures in the Antarctic Peninsula have risen by 2.5 degrees Celsius. Climate change led to the fact that in 1995 Larsen A with an area of 4000 sq. km was completely destroyed. In the early 2000s, an iceberg with an area of more than 3 thousand square meters broke off from Larsen B. km.
In December 2016, NASA obtained aerial imagery that showed a giant fissure 112 kilometers long, about 100 meters wide and about 500 meters deep had developed in Larsen C. This year it grew rapidly and by July had increased to 200 kilometers in length. The mass of ice here can reach a trillion tons.
The largest recorded iceberg, B-15, measured 295 x 37 km, covered an area of 11,000 square kilometers and weighed three trillion tons. It broke off the Ross Ice Shelf in March 2000, near Roosevelt Island, and then broke into smaller pieces in 2000, 2002, 2003. Six years later in 2006, several large pieces were seen in New Zealand.
In 1965, it was reported that an American icebreaker had discovered a 32,000 sq. km - more than the area of Belgium, but at that time there were no satellites with which to confirm this information.
According to Adrian Luckman, a professor at Swansea University and head of the MIDAS Antarctic project, a huge iceberg with an area of 5800 sq. km, a thickness of 350 m and a mass of more than 1 trillion tons that broke away from Antarctica on July 12 can last for several decades.
Professor Adrian Lachman stated:
“This iceberg is one of the largest in history, and its future is difficult to predict. It may remain in one piece, but it is more likely to break into fragments. Some of the ice may remain in this area for decades, other parts may drift north, to warmer waters.
Scientists plan to observe the movement of the breakaway iceberg. According to scientists, it ensures the connection of all the ice shelves of Antarctica, later they may begin to separate from the ice continent.
The main reason for the destruction of the Antarctic ice sheet is the flooding of its base with warm ocean water.
"What happened today is the result of natural causes. We do not know anything about the possible impact on these processes from the human-induced processes of global warming. However, the ice shelves are now in a very precarious position. Now the ice of Antarctica has receded to the farthest distance in the entire history of observations. We will be monitoring very closely for possible manifestations of instability in all ice shelves."," said Martin O'Leary, a Swansea University glaciologist.
Swansea University staff suggest that the new iceberg will not lead to a rise in world sea levels, and will not be associated with global warming.
If the ice shelves stop holding back the descent into the ocean internal parts glaciers of Antarctica, the level of the world ocean can rise by 10 cm, and this is a significant value by scientific standards.
Andrey Glazovsky, a leading researcher at the Institute of Geography of the Russian Academy of Sciences, Candidate of Geography, gave an interview to Sputnik radio and explained the ongoing processes in Antarctica:
"This is not the fault of global warming, this is a natural process: Antarctica is losing its mass like that. Snow falls on the continent, accumulates in the form of a giant mass - this is the ice sheet of Antarctica, and then such large pieces break off from it, mainly icebergs. Now Antarctica is in in general, it loses a little - and not "plus or minus", but absolutely loses - about 150 cubic kilometers in its pure form. That is, more flows out of it than comes in. By the way, this is not the largest iceberg in Antarctica, it is one of the ten largest icebergs that were observed. There were much more - about 11 thousand square kilometers there was a "piece" in 2000 "- Andrey Glazovsky said.
According to the scientist, the iceberg will not affect the level of the World Ocean, but may create problems for shipping:
“It’s not like the iceberg floated somewhere, it separated from the floating plate, became independent. Then its fate is this: it will slowly crawl away from Antarctica, go north. Then it can go to an area where shipping is observed, and there they can be trouble. Now it's hard to tell where it will go. There is a circular current there, and it can circle a little and go further. I'll tell you right away: it will not affect the level of the World Ocean, because it broke away from the floating plate. But if it crawled on continent, then the ocean level would rise by about three millimeters. This is very decent. Now the level of the World Ocean is rising by about three millimeters a year, but this is the contribution of all the glaciers of Antarctica and Greenland "- Andrey Glazovsky explained.
It is difficult to predict where the iceberg will move, at the moment it has sailed 13 kilometers from the continent.
Since it became dangerous to be on the glacier, scientists left it in the spring of 2017. And then they will watch the iceberg from space
Melting Antarctica:
Scientists have been monitoring the stability of this ice shelf for several years. Thomas Zurbuchen, a Swiss-American astrophysicist who has been appointed Associate Administrator of NASA's Science Mission Directorate since October 2016, published an image of the new iceberg on July 12, 2017 taken on NASA's Terra and Aqua satellites:
The blue color represents a warm surface - this is seen between a new iceberg and an ice shelf, as well as in areas of the open ocean and where the water is covered with thin ice. A lighter blue tone indicates intact or thicker ice.
“A careful analysis of the growth in the number natural disasters, extreme weather events around the world, as well as statistical indicators of space and geophysical parameters for last years showed an alarming trend towards their significant increase in a short period of time. These data indicate that the assumptions put forward by a number of scientists that the change in the Earth's climate for 100 years or more will be gradual in nature are incorrect, since in fact this process is much more dynamic.These are processes that humanity is not able to influence today, therefore, one should not underestimate their consequences, possible risks and difficulties for people in connection with upcoming events on Earth, one must prepare for these events. ». Quote from d ALLATRA SCIENCE scientists community salary« » .
A natural event of enormous magnitude, which scientists have been waiting for the past few years, has happened: on the morning of Wednesday, June 12, it became known that in the west of Antarctica a giant part of the Larsen C glacier broke away, resulting in the formation of one of the largest icebergs in history. Its mass is a trillion tons, its area is about 6 thousand square meters. km, which is comparable to a quarter of the territory of Wales. The report about the separation of the iceberg was given by the British Antarctic project MIDAS.
You can track the position of the iceberg in real time thanks to NASA satellite .
In 1893, the Norwegian captain and founder of the Antarctic whaling, Carl Anton Larsen, explored the coast of the Antarctic Peninsula on the ship Jason. Later, the huge wall of ice along which the captain sailed was named the Larsen Ice Shelf.
The area of the Larsen C glacier is 55 thousand square meters. km, which is almost ten times the area of the previously melted Larsen B. Today, Larsen C is considered the fourth largest glacier in the world.
The separation of a giant iceberg, scientists expected. The crack was first noticed back in 2011, and in 2014 it began to grow rapidly. The cleavage stretched for almost 200 km, separating the iceberg from the main body of the glacier in 10% of its area.
“This crack continues to grow, and eventually it will lead to the fact that a significant part of the glacier will break off like an iceberg,” scientists argued a year ago. In their opinion, after the breakaway, the remaining part of the ice shelf will become unstable and icebergs will continue to break away from it until Larsen C is completely destroyed. According to the researchers, in the near future, Larsen S is waiting for the fate of Larsen B.
The department of a giant iceberg coincided in time with the predictions of scientists. The fact is that only between May 25-31, the crack lengthened by as much as 17 km - the fastest growth since January.
According to scientists, now the crack is increasing in size, and currents and winds can now carry the breakaway iceberg towards the Atlantic Ocean. So far, scientists cannot say for sure whether the iceberg has broken into separate parts or is sliding, while maintaining its integrity.
“The detachment looks like a complete break off of the ice shelf,” said Ted Scambos, lead scientist at the National Snow and Ice Data Center in Colorado. - It is unusual that now the area of the shelf has become minimal in 125 years, since its first mapping. However, this behavior is typical for ice shelves in Antarctica.” The huge flat glacier, 200 meters thick, won't slide quickly, scientists say, but its movement needs to be monitored.
“Now we see one iceberg. It will probably break into small pieces over time,” suggests Adrian Luckman, professor of glaciology at the University of Swansea. In the meantime, scientists are arguing what caused the breakaway of such a giant iceberg - global warming or natural processes for Antarctica.
According to glaciologists, the breakaway iceberg was one of the ten largest on record. Iceberg B-15, which broke away from the Ross Ice Shelf in March 2000 and had an area of 11 thousand square meters, is considered the largest of the observed icebergs. km. In 1956, it was reported that the crew of an American icebreaker encountered an iceberg with an area of 32 thousand square meters. km. However, at that time there were no satellites that could confirm this.
In addition, Glacier C itself has also produced giant icebergs in the past that float freely. So, an object with an area of 9 thousand square meters. km broke away from the glacier in 1986.
The chairman of the polar commission of the Russian Geographical Society, Viktor Boyarsky, in an interview with the Nation News news agency, spoke about whether the breakaway iceberg poses a threat to navigation and whether this event will affect the balance in nature.
“Of course, a large piece has broken off. Now it will be carried out into the ocean, it will begin to wander until it melts. There will be certain warnings about this to ships, because, of course, it poses a danger to navigation, like any large floating object,” noted famous traveler and a polar explorer.
Viktor Ilyich confirmed that a fairly active decrease in the area of ice is taking place in Antarctica: glaciers are breaking off and collapsing. The scientist emphasized that in East Antarctica the situation is reversed, so everything in nature is in balance. In his opinion, a huge piece that broke off is not an unusual phenomenon, since such icebergs form regularly.
“Well, where should they go: a lot of ice is pressing down from above, the glacier is melting, pieces are breaking off, large or small. big time while he swims in the ocean."
The honorary polar explorer of Russia summed up that if this piece of ice floe was washed ashore, it would be able to freeze again and, thus, continue its "existence". As for storms, according to a professional traveler, they are not afraid of an iceberg.
News agency Nation News reported. tons, which broke away from the Larsen C glacier in Antarctica. According to preliminary data, its area is equal to six thousand square kilometers.
For scientists, this did not come as a surprise, since they had been waiting for this event for more than ten years and carefully followed the process.
The Larsen B Ice Shelf is critically endangered and is estimated to be gone by 2020. The Larsen A ice shelf existed until 1995, after which it was completely destroyed.
A whole region broke away from the mainland, probably together with penguins, which is comparable in area, and, possibly, in the number of inhabitants, with the Basque Country. The Basque Country is a territory that is simultaneously in France and Spain and requires independence from both of them. If in modern mainland Europe such a separation is unlikely, since the state is trying to cement its borders as much as possible, then in Antarctica a split is possible and inevitable.
Adrian Luckman, professor at the University of Swansea, UK: “The crack that broke off the iceberg has been visible on all satellite images since the 80s of the last century. This crack was growing all the time, the iceberg was bound to break off.”
The length of the crack in recent months has reached a depth of 500 meters and a length of about 200 kilometers. In satellite imagery, the crack looks like a cut piece of cake. It will take years for the ocean to absorb it. and be 100 stories tall. While this colossus will melt, decades will pass. The iceberg has not yet moved away from the parent ice floe, it broke away, but did not move to swim. This is a natural process. The mature glacier is supported and pushed into the water by younger ice, which also needs a place under the polar sun.
Nikolai Osokin, Candidate of Geographical Sciences: “The fact is that in this case we are talking about a process that happens regularly. The main property of glaciers is that they flow.
Scientists, knowing about the excess weight of the iceberg, assume that it will not go far from Antarctica, but the process of destruction into smaller ice floes will continue. Small icebergs can float to the side South America. As transmits Correspondent Lisa Gerson, modern location devices on ships should prevent a repetition of the tragedy of 100 years ago.
The British transatlantic steamer Titanic sank in the North Atlantic in 1912 when it collided with an iceberg sailing from the Arctic. At that time, this ship was the largest in the world, and the iceberg that killed it was by no means the largest. The largest one appeared only 100 years later, in mid-July 2017, during the coldest time of winter in the Southern Hemisphere.
British scientists have been watching the glacier for many years. This work was calm and not at all nervous for more than 30 years. Fragments in the water broke off from the ice shelf and collapsed. But these days Antarctica. She lost about 10% in weight. Such a sharp weight loss theoretically threatens to raise the water in the oceans and its cooling. But the British, who are accustomed to adding ice to whiskey, argue that the total volume of liquid in the world will not change, since this ice was already in the water.
