“He looked like a huge snake.” What did the victims of the Kolka glacier manage to see?

20 years ago there was a natural disaster in the Karmadon Gorge of North Ossetia. The Kolka glacier, which fell from the highlands, covered a distance of almost 20 kilometers in seven minutes and filled the valley, burying many buildings, recreation centers under it and killing 125 people, including 42 members of the film crew of the film director Sergey Bodrov Jr.

There is no single version of the causes of this largest glacial (that is, ice-related) catastrophe in Russia. Scientists tend to believe that several factors played a fatal role. About the catastrophe on September 20, 2002 and the current state of the ill-fated glacier, aif.ru spoke with senior researcher at the department of glaciology of the Institute of Geography of the Russian Academy of Sciences, Robert Chernov, who took part in expeditions to the Kolka glacier many times.

“The speeds there were wild”

— Is it true that the Karmadon catastrophe was a unique event in terms of science? They say scientists have never seen anything like this before.

— Quite right. The descent of the Kolka glacier in 2002 cannot be compared with previously known movements and collapses of glaciers. Such events have never been recorded by glaciologists — neither in their scale nor in their scenario.

Part of the glaciers collapses occur in almost all mountain systems, this is a normal phenomenon. But for the glacier to completely leave its bed, while flying almost two dozen kilometers along the valley in a short period of time — this has never happened before. And this, of course, greatly surprised scientists.  

Kolka Glacier a year before the 2002 disaster. Photo: Commons.wikimedia.org/Sergei Chernomorets

This scenario is completely different from previous glacier movements that have occurred repeatedly. The previous event was in 1969 and it looked different. This is how shifts usually occur: the glacier, having accumulated mass and reaching a critical value, begins to slowly move forward. Then he advanced almost 5 kilometers and stopped. Yes, it looks scary and makes an impression: the glacier is cracking, crawling, raking everything in front of it like a bulldozer, — but it is crawling, covering tens of meters in a day, and not flying at the speed of an express train.

Kolka's departure in 2002 was different. It was a colossal release of energy. In a matter of minutes, huge masses of ice, water and stones moved from the upper reaches to the lower reaches of the Karmadon Valley. The speeds there were wild, they exceeded 100 kilometers per hour, sometimes reaching up to 200 kilometers. This mass practically flew.

October 2002 Photo: Commons.wikimedia.org/Sergei Chernomorets

When we arrived in the valley in 2003, we saw that its slopes had been peeled to a height of 100-150 meters, in many places they were straightened, and even overlaps were visible: moving along the gorge, the glacier was thrown from one slope to another. It turned out to be such a slalom. Only a rocky ridge prevented these masses of ice from advancing further, and they stopped in the valley.

— Has this ice melted now?

— Initial estimates were such that it would melt in 30-35 years. But it played a role that in the Karmadon basin the average annual temperature is positive. The ice settled very quickly, covered with moraine (geological deposits in the form of stones and clay. — Ed.) and at the end in the end, almost all of it melted away.

Now this moraine material remains there in the form of a hilly relief. Somewhere under the thickness of the ice, perhaps there is still.

A section of the gorge covered with stones after the Kolka glacier descended. 2018 Photo: Commons.wikimedia.org/Alexander Baidukov

What do eyewitnesses say?

— So, there you can find something that was left after the disaster 20 years ago? For example, the car of the film crew of Sergei Bodrov?

— All this is buried in a multi-meter thickness of moraine material. You need to work as a bulldozer, an excavator, but the question is: for what? To pull out the wreckage of a car? Nothing solid could be left there. With such a scale of the catastrophe, everything that was in the path of this rampart, this ice and stone mudflow, was demolished and mangled.

And then, you should not look for the remains of the Bodrov group at the bottom of the gorge. There are eyewitness accounts who have repeatedly said that the film crew at that moment was not on the road, but was invited to a nearby village for a family celebration. They were seen by those who left there earlier.

I personally talked with an elderly woman who was invited to the same celebration, but did not reach it, because she had sore legs, and she at the moment the descent of the glacier stood on a hillock. I have never met another such person in Karmadon who saw the catastrophe with his own eyes. 

Traces of the descent of the glacier on the walls of the gorge. 2018 year. Photo: Commons.wikimedia.org/Alexander Baidukov

— What did she say?

— She described what she saw rather figuratively, but I had no doubts about her words. This is how it should have looked.

At the time of the disaster, it was already dusk. The woman said that she heard a rumble and a roar, and then a luminous mass jumped out of the valley and spread out at the foot of the slopes. According to her, the glacier was like a huge snake.

— And what could the people who at that moment were at the bottom of the gorge see and feel?

— It's hard to imagine. The growing rumble in the mountains — is always disturbing. But it was a rumble of a different nature: tens of millions of tons of ice and stones were moving at great speed. I don't think people have time to understand. Since the ground was also shaking, they might have thought it was a massive earthquake. But everything happened quickly, they hardly had time to realize that a glacier was flying at them. Moreover, I repeat, it was already dark.

Photo: Commons.wikimedia.org/NASA

The bed was completely empty

— What are the reasons for this catastrophe, which has become unique from the point of view of science?

— At first, it was not very clear what pushed Kolka out of its bed, especially since the glacier had not yet gained critical mass. Began to think there was a lot of controversy. Geologists said that this was seismic: the glacier was shaking, landslides were added to this, and it left. True, the rest of the glaciers for some reason remained in their places.

This version prevailed at first. But then the specialists of our institute noticed that there was a lot of water in the highlands. And volcanologists have registered in the basin, where Kolka used to lie, outcrops of volcanic gas. Then they came to the conclusion that the catastrophe was predetermined by volcanism. This version has become the main one. Near Kolka there is a dormant volcano Kazbek, in its bowels there is a magma chamber, quite close to the earth's surface. From it, apparently, periodically comes heat. This temperature is enough for the glacier to start melting from below. Water accumulated under it, it became more and more, and the water reduces the frictional force that keeps the glacier in its inclined bed. In the end, this friction weakened, and he fell down.

I think voids could have formed in the glacier, and it collapsed inward. This led to the movement of the entire mass.

— What does the place where Kolka was before the gathering look like now?

— The glacier is recovering. In the first days after the disaster, it turned out that his bed was completely empty — there was nothing left. This is a fairly spacious basin with steep sides and a flat bottom. And it was empty, the glacier disappeared completely, which also surprised scientists: this had never happened before. Then its rapid filling with ice began, but the process was uneven, slowed down.

Now the glacier has gained about a third of the volume that it had in 2002. It is 2.5 times smaller in area. The thickness has significantly decreased: if earlier it was 80-100 meters, now it is a maximum of 50, and on average — 30-40. And one gets the impression that the glacier is not particularly striving to add in size and volume. In recent years, little has changed: how much ice has accumulated, so much has melted in the summer. The glacier front has stabilized and is only moving forward a little, a few meters a year. There is an accumulation of ice in its rear part due to avalanches and collapses, but this is the norm.

I think Kolka will not recover to its previous volume in the foreseeable future. And, of course, you should not be afraid of its descent in the coming years.

— How are observations made?

— Our expeditions go there twice a year. We fix the state of the glacier, monitor its recovery: we take photographs from certain points and GPS mapping, put sensors in different places to record the temperature.

There is no continuous monitoring of the glacier, but this is not special needs. Now remote methods, satellite imagery are quite enough. It provides information both about the characteristics of the glacier and about the ice masses that accumulate above it.

By the way

Rescue work in Karmadon Gorge continued for more than 1.5 years. The bodies of 19 dead, dozens of body fragments were found. In addition to rescuers, the search was conducted by relatives of the missing, including members of the film crew of Sergey Bodrov. They set up a permanent camp in the gorge. It was hoped that someone managed to hide in the tunnel. Rescuers drilled 20 wells in the thickness of the ice, one of them fell into the tunnel, but it turned out to be filled with water.

The relatives of the victims attracted psychics. As a rule, they said that rescuers were looking in the wrong place, but that was where their help ended.

In May 2004, a decision was made to stop rescue and search operations.

Monument to those who died in 2002 during the collapse of the Kolka glacier in the Karmadon Gorge. Photo: RIA Novosti/Kazbek Basaev Rate the material

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