On the ship "Jason". The Larsen Ice Shelf consisted of three large glaciers - Larsen A, Larsen B and Larsen C - with a total area the size of the island of Jamaica. Partially destroyed due to global warming (to date only the Larsen C glacier has survived).
Over the past half century, temperatures in southwest Antarctica, on the Antarctic Peninsula, have increased by 2.5 °C. In 1995, the Larsen A glacier broke off from the main body of the glacier. In 2002, an iceberg with an area of over 3,250 km² and a thickness of 220 m broke off from the Larsen glacier, which actually means the destruction of the glacier. The destruction process took only 35 days. Before this, the glacier remained stable for 10 thousand years, since the end of the last ice age. Over thousands of years, the thickness of the glacier decreased gradually, but in the second half of the 20th century, the rate of its melting increased significantly. The melting of the glacier led to the release of a large number of icebergs (over a thousand) into the Weddell Sea
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- Science news: the destruction of Antarctica's ice shelves is a direct threat to the planet's ecological balance
Coordinates: 67°30′ S w. 62°30′ W d. / 67.5° S w. 62.5° W d.(G)-67.5 , -62.5
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See what “Larsen Glacier” is in other dictionaries:
The largest ice shelves in Antarctica. ... Wikipedia
The Larsen Glacier is in the process of destruction. NASA photo Larsen Glacier is an ice shelf off the coast of the Antarctic Peninsula. Named in honor of the Norwegian captain K. A. Larsen, who explored the coast of the Antarctic Peninsula in 1893 on a ship... ... Wikipedia
Ross Ice Shelf Ice shelves are floating or partially bottom-supported glaciers flowing from the shore into the sea, in the form of a slab that thins towards the edge, ending in a cliff. They represent a continuation of land ice sheets, less often... ... Wikipedia
- (Larsen Shelf Ice) in Antarctica, on the eastern coast of the Antarctic Peninsula. Area with glacial domes approx. 86 thousand km². Ice thickness 150,500 m... Big Encyclopedic Dictionary
- (Larsen Shelf Ice), in Antarctica, on the eastern coast of the Antarctic Peninsula. The area with glacial domes is about 86 thousand km2. Ice thickness 150,500 m. Named after K. A. Larsen. * * * LARSENA SHELF GLACER LARSENA SHELF... ... encyclopedic Dictionary
- (Larsen Shelf Ice) one of the largest ice shelves in Antarctica. Forms the eastern ice coast of the Antarctic Peninsula for more than 800 km (between 64.5° and 72.5° S). The greatest width is about 200 km. The area is about 86 thousand... Great Soviet Encyclopedia
- (Larsen Ice Shelf), in West. Antarctica, to the east. side of the Antarctic Peninsula. It forms an ice coast for more than 600 km, width up to 200 km. The ice thickness is 150–500 m. The northeast is blocked by sea ice of the Weddell Sea all year round. Approximately… … Geographical encyclopedia
The Larsen Glacier is in the process of destruction. NASA photo Larsen Glacier is an ice shelf off the coast of the Antarctic Peninsula. Named in honor of the Norwegian captain K. A. Larsen, who explored the coast of the Antarctic Peninsula in 1893 on a ship... ... Wikipedia
Ross Ice shelves are floating or partially bottom-supported glaciers flowing from the shore into the sea, in the form of a slab that becomes thinner towards the edge and ends in a cliff. They are a continuation of ... Wikipedia
Glaciers Larsen A, Larsen B and Larsen C are in the process of destruction. NASA photo, March 2003
As a result of global warming, snow cover is decreasing in thickness, which could lead to the disappearance of Antarctic ice shelves within two hundred years. The rate of warming on the Antarctic Peninsula is very high; This is not observed in any other region of Antarctica. The melting of the ice shelf and the rapid movement of ice into the sea can cause rising water levels in the seas and lead to disruption of the ecological balance of the planet.
Cracks separating the Larsen glaciers in February 2004
Over the past 50 years, temperatures on the Antarctic Peninsula have risen by 2.5 degrees (much more than the global average). As a result, five ice shelves retreated and the extent of the land ice sheet changed. Thus, in 1995 and 2002, two floating ice shelves Larsen A and B in the north of the Antarctic Peninsula suddenly collapsed. The ice shelf, 200 meters thick, broke up into small icebergs and individual fragments within one month. After the destruction, only the Larsen C glacier survived.
Larsen B Glacier is disintegrating. February 2005
Larsen Glacier is an ice shelf off the coast of the Antarctic Peninsula. Named in honor of the Norwegian captain K. A. Larsen, who explored the coast of the peninsula in 1893 on the ship Jason. The Larsen Ice Shelf consisted of three large glaciers - Larsen A, Larsen B and Larsen C - with a total area the size of the island of Jamaica.
Collapse of Larsen B Glacier
This sudden death of the glacier is caused not so much by natural causes as by abnormally high temperatures in the Antarctic region caused by the influence of human economic activity.
Larsen C Ice Shelf and surrounding Antarctic waters
Scientists believe that a chain reaction has begun in Antarctica. By breaking up into icebergs and freeing up the space it had occupied for ten thousand years on the shelf, Larsen B opened the way for glaciers lying either on solid ground or in shallow water to slide into the warm sea. The deeper the “land” glaciers slide into the ocean, the faster they will melt and the higher the level of the world's oceans will be and the faster the ice will melt... This process will last indefinitely. More precisely, until the last Antarctic glacier dissolves in the water.
Behind the ice of the Larsen S glacier
Iceberg collision in Antarctica. The Rhode Island-sized iceberg B-09B (center right in this image) collided with the edge of the Mertz Glacier in East Antarctica. The image was obtained from a NASA satellite.
Pine Island Glacier in West Antarctica before destruction
Unfortunately, the destruction of icebergs and glaciers as a consequence of global warming is no longer a rarity. So, in 2013, a giant iceberg broke off from one of the largest glaciers in Antarctica, Pine Island. German satellites discovered that the crack reached from one edge of the glacier to the other.
Melting of the Pine Island Glacier
Scientists estimated the area of the broken iceberg to be approximately 720 square kilometers. For comparison, the area of Moscow is about a thousand square kilometers. The new iceberg was the leading edge of an ice shelf rapidly sliding into the ocean.
The dry valleys of Antarctica are located west of the McMurdo Valley. They are named so because of the extremely low humidity and lack of snow and ice cover. Photosynthetic bacteria have been found in relatively wet rocks. Scientists believe that the Dry Valleys are more similar to Mars than any environment on Earth.
Ross Ice Shelf
Only sharp reductions in greenhouse gas emissions will help preserve ice shelves. If fossil fuel combustion continues at current levels, it will lead to the destruction of almost all ice shelves on the Antarctic Peninsula.
Scientists are now observing the much larger Ross Ice Shelf. If it collapses, sea levels around the world will rise by five meters over the next few centuries.
When Ross encountered a majestic ice shelf on his way to Antarctica, he noted: “Yes, walking here is like walking through the cliffs of Dover.”
The length of the glacier from south to north is about 850 km, from east to west - about 800 km. It has an area slightly less than the size of France.
A video posted on YouTube, which captured the moment of the destruction of a large iceberg off the coast of Newfoundland, collected 1.3 million views and more than a thousand comments in five days. Eyewitnesses barely had time to swim away from the scene.
A unique video was shot by a married couple from Canada, Wanda and Rick Steed, during a boat trip. “When the iceberg began to collapse, it seemed to me that my heart was going to jump out,” admitted Rick. Their boat was 150 meters from the collapsing giant, but the Canadians managed to quickly sail to a safe distance.
A huge iceberg will soon break off from Antarctica January 20th, 2017
Photo of the glacier from NASA. December 2016.
We have all heard about global warming, but how exactly it affects the state of nature is not always possible to see clearly - most often changes occur slowly and imperceptibly. This time, the inhabitants of the planet have the opportunity to observe much more rapid changes caused by changes in temperature on Earth: an iceberg is about to break off in a few weeks, which will be one of the ten largest in history.
Moreover, its flooding could lead to a rise in sea levels...
The crack is only 20 km away from the ocean.
In 1893, the Norwegian captain and founder of Antarctic whaling, Carl Anton Larsen, explored the coast of the Antarctic Peninsula on the ship Jason. Later, the huge ice wall along which the captain sailed would be called the Larsen Ice Shelf.
Initially, the ice shelf consisted of three parts - Larsen A, Larsen B and Larsen C (Larsen C was the largest of them). Larsen A was the first to break away - he went under water in 1995. Just seven years later, Larsen B also broke away from the main body of the glacier. This iceberg was quite impressive in size - its area was 3250 km², and its thickness was 220 m. Larsen B lasted on the water for a little over a month and eventually completely collapsed.
And now the only “surviving” glacier, Larsen S, whose area is 55 thousand square meters, is under threat. km, which is almost ten times the area of the “deceased” Larsen B and represents half the area of Iceland. Today, Larsen C is considered the fourth largest glacier in the world.
Destruction of the second part of the glacier - Larsen V.
After 10 thousand years, while the glacier remained unchanged, recent decades have significantly changed its history. And then in December 2016, scientists noticed a crack along the remaining part of the Larsen S ice shelf. This crack separates a huge block of ice with an area of about 5,000 km² (this is twice the total area of Moscow). The crack is relatively narrow - only 100 m wide, but scientists believe that it goes half a kilometer deep.
Antarctic coast and Larsen Glacier.
According to the results of computer modeling and analysis of satellite images by scientists from the UK who are involved in the MIDAS project, in the last five months alone (from March to August 2016) the glacier crevasse has increased by 22 km (13.67 miles) in length and is now 130 km (80 miles). For comparison, between 2011 and 2015 the crack increased by 30 km in length. In addition, the crack is currently 350 m wide.
Another 20 km - and the block will break off completely. Therefore, scientists assume that this event is a matter of weeks. There are different versions of the reasons for this split, but global warming, directly or indirectly, in any case had an effect on this.
If this entire block were to sink into the ocean, despite its size, it would not make a significant difference at sea level. It would be another matter if the entire Larsen Glacier sank - and this could happen, since without a breakaway piece the glacier could become much less stable. If the entire glacier eventually goes under water, the level of the world's oceans will rise by 10 centimeters.
According to glaciologist David Vaughan, “today the situation looks more than alarming: the sea level in the Atlantic has risen, and the Larsen C glacier is larger than both Larsen A and Larsen B were. And if it also melts, then we can today using a mathematical model to predict what the level of the World Ocean will be in 2100. It will rise by about half a meter. It’s not just climate change, it’s changing virtually the entire coastline on the planet.”
Interestingly, in June, a study appeared in Nature Communications that showed melt ponds formed on the surface of Larsen C. And the day before, researchers from Durham University came to a similar conclusion. Scientists analyzed hundreds of satellite images and meteorological observation data of the Langhovde glacier in East Antarctica and found that from 2000 to 2013 alone, about 8 thousand new lakes appeared in Antarctica. Experts suspect that water from some of these lakes may seep beneath the surface of the ice, threatening the stability of the entire glacier.
Russian scientists note that there is nothing scary or surprising in this, since the Larsen Ice Shelf consists of volcanoes.
“Antarctica is a country of volcanoes; there are many active, subglacial, and conserved ones. The Larsen Ice Shelf is made up of three volcanoes. At one time there had already been a very powerful destruction of two sections of the glacier. It caused a wide resonance then. But now they have almost completely recovered in the form of perennial fast ice. That is, everything is returning to normal,”? Andrey Korotkov, senior researcher at the Ice Regime and Forecasts Department of the Arctic and Antarctic Research Institute, explained to NSN.
He added that the cataclysms observed in recent decades are associated with the revival of volcanic and seismic activity everywhere. “This is a highly balanced system that returns everything to its place. The broken pieces of the Larsen Ice Shelf have now been put back in their place, even if in the form of perennial fast ice,” ? said the scientist.
At the same time, Korotkov noted that the appearance and growth of the crack is quite possibly associated with the activation of seismic processes in the region. But he added that this will not lead to the melting of glaciers as a whole.
In 1893, the Norwegian captain and founder of Antarctic whaling, Karl Anton, explored the coast of the Antarctic Peninsula on the ship Jason. Later, the huge ice wall along which the captain sailed would be called the Larsen Ice Shelf.
Initially, the ice shelf consisted of three parts - Larsen A, Larsen B and Larsen C (Larsen C was the largest of them). However, Larsen A, whose area was 1.5 square meters. km, completely collapsed at the end of the 20th century - in 1995 it broke away from the main glacier and melted in just a few months. Then the researchers decided that the two remaining glaciers were destined for a different fate. However, already at the beginning of the 21st century, in 2002, Larsen B, which remained stable for 12 thousand years, disintegrated into small icebergs in just 35 days.
According to scientists, Larsen B collapsed due to rising air temperatures over Antarctica, as well as due to an increase in the average temperature of the World Ocean.
And now the only “surviving” glacier, Larsen S, whose area is 55 thousand square meters, is under threat. km, which is almost ten times the area of the “deceased” Larsen B and represents half the area of Iceland. Today, Larsen C is considered the fourth largest glacier in the world. According to computer modeling and analysis of satellite images by scientists from the UK who are involved in the MIDAS project, in the last five months alone (from March to August 2016) the glacier crevasse has increased by 22 km (13.67 miles) in length and is now 130 km ( 80 miles). For comparison, between 2011 and 2015 the crack increased by 30 km in length. In addition, the crack is currently 350 m wide.
Project MIDAS
MIDAS is a UK research project that is studying the effects of global warming on the Larsen S Ice Shelf.
“This crack continues to grow and will eventually cause a significant portion of the glacier to break off like an iceberg,” the study authors commented (specifically, 12% of the glacier is expected to break off). The remainder of the ice shelf will become unstable and icebergs will continue to break off until Larsen C is completely destroyed. According to researchers, in the near future Larsen S will meet the fate of Larsen B.
According to scientists, in the near future an iceberg with an area of about 6 thousand square meters will break off from the glacier. km (2316 miles), which is comparable to the area of Delaware, one of the US states. Then the iceberg will melt.
UK scientists warn that when the entire glacier collapses, sea levels will rise by as much as 10cm.
Rising sea levels will pose a threat primarily to countries with long coastlines and island countries.
Researchers have not yet specified exactly when a giant piece will break off from the glacier, but suggest that this could happen in the next few years. According to them, this will be one of the largest events in the entire history of mankind.
UNIVERSAL IMAGES GROUP
Interestingly, in June in Nature Communications appeared study that found melt ponds formed on the surface of Larsen C. And the day before, the science department of Gazeta.Ru reported that researchers from Durham University had come to a similar conclusion. Scientists analyzed hundreds of satellite images and meteorological observation data of the Langhovde glacier in East Antarctica and found that from 2000 to 2013 alone, about 8 thousand new lakes appeared in Antarctica. Experts suspect that water from some of these lakes may seep beneath the surface of the ice, threatening the stability of the entire glacier.
The separation of a 1 trillion ton iceberg will fundamentally change the landscape of the entire Antarctic Peninsula
Moscow. July, 12. website - One of the largest icebergs ever recorded has broken off in the southwest of Antarctica, on the Antarctic shelf, the BBC reports.
This iceberg is expected to be named "A68". It is believed to be one of the top ten most massive icebergs ever recorded by scientists. However, it is half the size of another giant ice floe, B-15, which broke off on the Ross Ice Shelf in 2000.
A block of ice about 200 m thick and about 6 thousand square meters in size set off for free floating. km., this is about two and a half Moscow. The weight of the broken ice is about 1 trillion tons, Business Insider clarifies.
The event did not come as a big surprise. Glaciologists (specialists in natural ice) knew that sooner or later this would happen. The development of a large crack on the Larsen Ice Shelf has been observed for more than ten years. The collapse of the Larsen S ice shelf began on the eastern front of Antarctica in 2014.
The Larsen Ice Shelf consisted of three large glaciers - Larsen A, Larsen B and Larsen C. Now the last of the remaining ones, Larsen C, has broken up; it has lost more than 12% of its area. Back in June, the split in it reached 13 km from the edge of the glacier.
MODIS (Moderate Resolution Scanning Spectroradiometer) image of the shelf and iceberg breakaway.
The leading researcher of the British research group Project MIDAS, which has been monitoring the ice shelf since 2014, professor of glaciology at the British Swansea University Adrian Luckman predicted that the iceberg would break off from the shelf in the very near future.
“At the moment we see one large iceberg. Most likely, it will break into small pieces over time,” the scientist said.
Reports indicate that the A68 may remain in roughly the same area where it is now for many years. In this case, its mass will not decrease significantly for a long time. According to another scenario, the iceberg will move to warmer waters, and then the melting process will proceed quite quickly.
If winds and currents direct the iceberg to the north of Antarctica, there will be a real threat to shipping. Experts still hope that the glacier will not float far; they will closely monitor it.
A press release from the European Space Agency on July 5 suggested that the current could carry the iceberg, partially or completely, northward, all the way to the Falkland Islands, which lie 1,500 km from Larsen S.
Days before the iceberg set off to drift across the Southern Ocean, Noel Gourmelin, a glaciologist at the University of Edinburgh, and his colleagues estimated that the fragment would be about 190 meters thick and contain about 1,155 cubic meters. km of frozen water. This volume is enough to fill more than 460 million Olympic swimming pools or fill Lake Michigan, one of the largest bodies of freshwater in the world.
Scientists believe that the fault was most likely triggered by climate change. However, as Lachman emphasized, there is no conclusive evidence that the calving of a giant iceberg is associated with climate change. Meanwhile, over the past 50 years, temperatures in southwest Antarctica, on the Antarctic Peninsula, have increased by 2.5 C.
According to experts, the iceberg is unlikely to significantly raise the level of the world's seas. However, the rest of the shelf may be less stable than before the fault. There is a possibility that the destruction of the Larsen S glacier will continue and it will suffer the same fate as its neighbor, the Larsen B glacier. In 2002, an iceberg with an area of over 3250 square meters broke off from it. km and a thickness of 220 m, after which the glacier continued to collapse. Glacier "Larsen A" with an area of 4 thousand square meters. km was completely destroyed in 1995.
