Antarctica is far away If the Arctic is a bowl of ice-covered ocean surrounded by land, then Antarctica is a huge ice-covered continent surrounded by sea. The living conditions on this glacier-covered land are so difficult and unusual that in some places they resemble more

For quite a long time it was believed that Antarctica is the only continent on Earth that does not have constantly flowing rivers. Only in the summer, when snow and ice melt, do temporary rivers of melt water appear in the coastal areas and Antarctic oases, flowing into the ocean or lakes.

But in some areas, melting and meltwater runoff are observed over fairly large areas and at considerable altitudes. Particularly large streams have been found on the Ketlitsa Glacier and McMurdo Ice Shelf, as well as on the Lambert Glacier. For example, on the surface of the Lambert Glacier, intensive melting begins at an altitude of 900 meters above sea level at a distance of 450 kilometers from the coast, and the resulting streams, constantly replenishing, reach the sea.

McMurdo Glacier

“We used to think that water moved very slowly under ice,” said Professor Duncan Winham, who led the research team. “But new data shows that these lakes are exploding like the cork popping out of a champagne bottle, releasing streams that migrate over very long distances.”

Underwater rivers have been spotted on satellite images. Scientists saw that the ice surface was lower over one of the lakes, but higher over the other two, located 290 kilometers away. They believe that this difference is created by water flow from one lake to another, and calculated that 1.8 km3 of water moved there over 16 months. “These lakes are like beads, in which the beads are the lakes themselves, connected by a river of water,” Winham says. Scientists believe that when the pressure in one of the lakes increases, a flow of water fills the next bead down the string.

Lakes in Antarctica are also found mainly on the coast. Like Antarctic streams and rivers, they are very unique. There are dozens of relatively small lakes in coastal oases. It is interesting that some lakes open up in the summer and become free of ice, others never (at least in the last tens of years) are freed from the ice cover that bound them, and finally, there are lakes that, despite severe frosts, do not freeze even in the most severe winter. The latter include salt lakes. The water in these lakes is so mineralized that its freezing point is much below zero. Lakes that do not open for many years are found only on the icy continent.
The largest of the Antarctic lakes is Lake Figurnoe in the Banger oasis.

Oasis Banger

Curiously meandering among the hills, it stretches for 20 kilometers. Its area is 14.7 square kilometers, and its depth exceeds 130 meters. There are several lakes with an area of ​​more than 10 square kilometers in the Victoria Oasis. Lakes with an area of ​​up to 8 square kilometers are located in the Vestfold oasis.

Lake Vostok

When you look at a photograph like this, taken on the shore of a lake, might you think that it was taken in the depths of the continent of Antarctica? I also thought that this continent is covered at all times of the year, albeit not with a thick layer of ice, but there are no huge areas of open land, much less with rivers and lakes. The coast thaws, well, a couple of kilometers inland - that’s all. But it turns out that this is not so...

We can conclude that there are no multi-kilometer thick ice (at least off the coast)

Antarctic Lake Vanda. The length of the lake is 5 km and has a maximum depth of 69 m.

Huge ice-free expanses in Antarctica

This is what it looks like on satellite images. Territory approximately 30x50 km without ice and snow

Relief of this place

I learned about this place from this video:

Some will say what's wrong with this summer period The ice melted and the valleys were exposed. But the fact is that even in winter there is no accumulated ice, not even snow.

Lake in winter

Victoria Land. One of the McMurdo Dry Valleys

Agree, this is not an Antarctic landscape at all. Either this is huge water erosion at work, or these are faults in earth's crust, or, as a version, a huge ancient quarry.

Wright Valley. Desert

Glaciers are trying to get into the valleys. But either there is not enough pressure from their main masses, or the temperature in the valley due to a geothermal anomaly is such that they melt, and thanks to this they allow rivers to appear. Yes, real rivers in Antarctica:

Onyx - Most long river Antarctica.
Located in the Wright Valley in Victoria Land, in the McMurdo Dry Valleys, characterized by an almost year-round absence of snow, high levels of solar insolation and fairly high summer temperatures. The length of the river is about 30 km. Lake Vanda flows into it.
The water level in the river is subject to strong daily and seasonal fluctuations. The Onyx has several tributaries and flows only during the late Antarctic summer (February, March). During the rest of the time, the river flow looks like a bare ribbon of ice. Sometimes the river cannot reach Lake Vanda for several years. But there are also unique floods; during one of them, in 1984, New Zealand rafters even went down the river.
There are no fish in the river, but there are microorganisms and algae, the bloom of which can be observed.
There are weather stations along the river, and at the mouth of the river there is the New Zealand Wanda station
(founded in 1968). Interestingly, the maximum air temperature at the station, recorded on January 5, 1974, was +15.0 °C, which is apparently the temperature record for the entire Antarctica.

So why is there no snow and “multi-million-year-old” ice (in quotation marks) in these valleys? Why does it snow so little here? It’s hard to believe that precipitation is carried away by winds blowing at a speed of 320 km/h. First of all, the speed of such winds. Or maybe, for some reason, the flood waters could not overflow here and, accordingly, freeze? Or did the temperature of the earth's surface melt all the ice? The temperature of deep waters is 23 degrees. Lake Vanda talks about this.

In the English language it is written that Lake Vanda is a hypermineralized lake with a salinity more than ten times greater than sea ​​water, greater than the salinity of the Dead Sea, and perhaps even greater than that of Lake Assal (Djibouti). Lake Vanda also, which means that the deeper waters of the lake do not mix with the shallow waters. There are three different layers of water ranging in temperature from 23°C at the bottom, 7°C in the middle layer and 4-6°C in the upper layers. Those. geothermal lake.

Let's continue our further tour of Antarctica.

McMurdo Station is nearby on the island, on the shore of the bay. The hill looks like a waste heap. 77° 50" 35.70" S 166° 38" 50.51" E

Its height is higher than the level of neighboring mountains

Flat surface of mountains

Why is Antarctica photographed by satellites in winter? Just like the Arctic, by the way. But the panoramio service also has summer photos.

As you can see from the photographs, McMurdo Station is home to a large contingent of researchers. Capital buildings, a lot of machinery and equipment. The station is located on an island in McMurdo Sound. A central mountain the island is a volcano:

The diameter of the larger crater is about 500m. But two geologically young craters are located in an older one. It is more than 4 km in diameter.

This is the Erebus volcano. Clouds of steam sometimes escape from the crater

As you can see, Antarctica lives a vibrant geological life and in some places it is not at all what they show us.

Rivers and lakes

Antarctica is the only continent on Earth that does not have constantly flowing rivers. Only in the summer, when snow and ice melt, do temporary rivers of melt water appear in the coastal areas and Antarctic oases, flowing into the ocean or lakes. In some areas, melting and meltwater runoff are observed over fairly large areas and at considerable altitudes. Particularly large streams have been found on the Ketlitsa Glacier and McMurdo Ice Shelf, as well as on the Lambert Glacier. For example, on the surface of the Lambert Glacier, intensive melting begins at an altitude of 900 meters above sea level at a distance of 450 kilometers from the coast, and the resulting streams, constantly replenishing, reach the sea.

Of the rivers flowing in oases along channels laid in ice-free soil, the Onyx River in the Wright Oasis on Victoria Land has the greatest length - about 30 kilometers. The Victoria River in the oasis of the same name has a slightly shorter length.

A dense network of temporary glacier streams comes to life in the summer in the oases of Banger and Schirmacher, where they reach a length of 20-30 kilometers. Since they are all fed by the melting of the glacier, their water and level regimes are completely determined by the course of air temperature and solar radiation. The highest flows in them are observed during the hours of the highest air temperatures, that is, in the afternoon, and the lowest - at night, and often at this time the riverbeds dry out completely. As a rule, glacier streams and rivers have very winding channels and connect numerous glacier lakes. Open channels usually end before reaching the sea or lake, and the watercourse makes its way further under the ice or in the thickness of the glacier, like underground rivers in karst areas.

With the onset of autumn frosts, the flow stops, and deep channels with steep banks are covered with snow or blocked by snow bridges. Sometimes almost constant drifting snow and frequent snowstorms block the beds of streams even before the flow stops, and then the streams flow in ice tunnels, completely invisible from the surface. Like cracks in glaciers, they are dangerous because heavy vehicles can fall into them. If the snow bridge is not strong enough, it may collapse under the weight of a person. True, compared to glacial cracks, the depth of which is measured in tens or even hundreds of meters, this danger is not so formidable.

There are cases when, during intense melting, water, accumulating in glacial lakes, suddenly breaks through the ice dam and rushes down in a wide, stormy stream. This is exactly what happened in 1961 at the height of the south polar summer at Novolazarevskaya station. Streams of gushing water flooded most of the station territory and threatened to carry away Construction Materials and other expeditionary property. The station was still under construction at that time. I had to interrupt construction works and take immediate action to save property from unexpected flooding. Everyone who was at the station at that time took part in the emergency work; All the equipment available to the polar explorers was used, and after several hours of intense, dedicated work, the danger passed. The water was diverted through a specially dug canal, and a strong dam was built along its previous path.

Lakes in Antarctica are also found mainly on the coast. Like Antarctic streams and rivers, they are very unique. There are dozens of relatively small lakes in coastal oases. It is interesting that some lakes open up in the summer and become free of ice, others never (at least in the last tens of years) are freed from the ice cover that bound them, and finally, there are lakes that, despite severe frosts, do not freeze even in the most severe winter. The latter include salt lakes. The water in these lakes is so mineralized that its freezing point is much below zero. Lakes that do not open for many years are found only on the icy continent.

The largest of the Antarctic lakes is Lake Figurnoe in the Banger oasis. Curiously meandering among the hills, it stretches for 20 kilometers. Its area is 14.7 square kilometers, and its depth exceeds 130 meters. There are several lakes with an area of ​​more than 10 square kilometers in the Victoria Oasis. Lakes with an area of ​​up to 8 square kilometers are located in the Vestfold oasis.

Among the Antarctic lakes there are bodies of water with a very unusual temperature distribution over depth. Thus, relatively recently, American biologists examining lakes in Victoria Land discovered a very interesting, at first glance even mysterious, body of water not far from the Antarctic base of McMurdo. The climate in these places is harsh, the average annual air temperature is below -20° and even at the height of the southern polar summer it never rises above 0°. The lakes in these places are covered with ice all year round. As you know, the water temperature in frozen freshwater lakes does not exceed 4°. It is at this temperature that water has the greatest density and can remain in the bottom layers of the reservoir, while at the top there is water with a lower temperature, down to 0°. Imagine the surprise of the researchers when they discovered in lakes covered with a thick layer of ice, water with a temperature much higher than 4°!

Particularly interesting in this regard was Lake Vanda, located in the Wright Oasis. Its length is about 8, its width is more than 1.5 kilometers, and its depth reaches 66 meters. All 13.6 square kilometers of the lake's surface are covered with ice about 4 meters thick, which by all indications has remained on the lake for at least the last several decades. Only in summer do narrow water banks form, which quickly freeze with the onset of autumn frosts. Directly under the ice, the water temperature, as one would expect, is close to 0°, but with depth it quickly increases and at the bottom exceeds 25°! In the ocean, such warm water can only be found in the tropical zone, and in the lakes of our country, even on the warmest summer days, the water rarely warms up to such a temperature. Why is the lake, in whose waters a huge amount of heat has accumulated, covered with ice?

The fact is that water at a certain depth under the ice becomes salty, and with depth its salinity increases quite quickly, and at the bottom the concentration of salts is 10-15 times higher than in sea water. Due to this distribution of salinity, the density of water, despite the increase in temperature, increases with depth, and therefore convective mixing, and therefore the transfer of heat to the surface, does not occur. Since the lake is covered with ice all year round, the wind cannot cause either wind currents or waves, which in open reservoirs contribute to the mixing of waters and smoothing of vertical temperature gradients. The absence of such mixing explains the existence of ice cover on Lake Vanda for many years despite high temperatures water in its deep layers. Intensive cooling occurs here only in the upper, fresh layer, on the surface of which a thick ice cover has formed.

Where did such warm water come from in the Antarctic lake? In the zone temperate climate, where the conditions for warming up the water seem to be more favorable, in lakes with a similar distribution of salinity, and therefore density, the opposite picture is observed. IN Orenburg region there is Lake Razval, formed at the site of rock salt production; its depth is about 20 meters. In this area, the warm period lasts more than 200 days a year, and the sun's height in summer reaches 63°. On the surface of the lake on hot summer days, the water heats up to 25-28°, and at the bottom throughout the summer the temperature remains below -8°! This phenomenon is called “permafrost.” In Antarctica climatic conditions are especially favorable for the existence of such permafrost, so the case of Lake Vanda was unexpected and completely mysterious.

Some scientists have suggested that the water in this lake is heated by the sun's rays, which during the short Antarctic summer penetrate under the ice, like through the glass of a greenhouse, and give off their energy to the lower layers of water. Thus, they said, Lake Vanda is a kind of solar energy trap, and ice plays the same role as glass in a greenhouse. The calculations performed by these scientists seemed to confirm this hypothesis. However, later studies, in which Soviet scientists took part, showed that water warms up due to heat coming from below, from the depths of the earth’s crust. Ice cover and upper, less dense layers of water play the role of a fur coat that protects deep warm waters from cooling.

There are lakes on the coast of Antarctica that were formed as a result of the backwater of snowfields or small glaciers. Water in such lakes sometimes accumulates for several years until its level rises to the upper edge of the natural dam. Then excess water begins to flow out of the lake. A channel is formed, which quickly deepens, the water flow increases, which further contributes to the deepening and expansion of the channel. As the channel deepens, the water level in the lake drops and it shrinks in size. In winter, the dry riverbed is covered with snow, which gradually becomes compacted, and the natural dam is restored. Next summer season The lake begins to fill with meltwater again. Several years pass until the lake is filled and its waters again break into the sea.

This is exactly what happened at the beginning of 1969 with Lake Glubokoe, located on the territory of the Soviet Antarctic Meteorological Center Molodezhnaya, at a distance of one kilometer from the sea. At three o'clock on January 18, the water level in this lake reached the upper edge of the ice dam that fenced it off from the sea, and water flowed from the overflowing lake along the surface of the glacier. Six hours later, she had already washed the channel 4-5 meters wide and up to 2 meters deep. By the end of the day, the channel deepened to 7 meters, and at 6 o’clock the next day, a stream of water rushing at a speed of almost 3 meters per second sawed right through the glacier. Water in an ice gorge up to 10 meters deep and 7-10 meters wide flowed over the rocky bed. The water flow in this stream reached 20 cubic meters per second. The water level in the lake dropped by almost 7 meters, resulting in the area of ​​the reservoir from 424,000 square meters decreased to 274, that is, by more than a third.

As a result of the breakthrough of the lake waters and the formation of a hole, the village of the meteorological center was divided into two parts. Telephone lines and electrical cables were severed. The overpass along which the high-voltage line runs, supplying electricity to all the main facilities of the village, is under threat of destruction. To eliminate the consequences of this breakthrough, the Molodezhnaya polar explorers had to work hard.

After a few days, the water flow in the stream flowing from the lake decreased to 2-3 cubic meters per second, and with the onset of cold weather and the cessation of thawing, the riverbed dried out. In winter it was completely covered with snow. Such breakthroughs of water from Lake Glubokoe into the ocean occur periodically, apparently once a decade.

Comparing Antarctica with other continents, it can be noted that there are absolutely no wetlands on the South Pole continent. However, in the coastal strip there are peculiar glacial “swamps”. They form in summer in depressions filled with snow and firn. Melt water flowing into these depressions moistens the snow and firn, resulting in a snow-water porridge, viscous, like our usual swamps. The depth of such “swamps” is most often insignificant - no more than a meter. On top they are covered with a thin ice crust. Like real swamps, they are sometimes impassable even for tracked vehicles: a tractor or all-terrain vehicle that gets stuck in such a place, stuck in a snow-water slurry, will not get out without outside help.

We can conclude that there are no multi-kilometer thick ice (at least off the coast)

Antarctic Lake Vanda. The length of the lake is 5 km and has a maximum depth of 69 m.

Huge ice-free expanses in Antarctica

This is what it looks like on satellite images. Territory approximately 30x50 km without ice and snow

Relief of this place

I learned about this place from this video:

Some will say what’s wrong here, in the summer the ice melted and the valleys were exposed. But the fact is that even in winter there is no accumulated ice, not even snow.

Lake in winter

Victoria Land. One of the McMurdo Dry Valleys

Agree, this is not an Antarctic landscape at all. Either this is a huge amount of water erosion at work, or these are faults in the earth’s crust, or, as a version, a huge ancient quarry.

Wright Valley. Desert

Glaciers are trying to get into the valleys. But either there is not enough pressure from their main masses, or the temperature in the valley due to a geothermal anomaly is such that they melt, and thanks to this they allow rivers to appear. Yes, real rivers in Antarctica:

Onyx - The longest river in Antarctica.
Located in the Wright Valley of Victoria Land, in the McMurdo Dry Valleys, characterized by an almost year-round absence of snow, high levels of solar insolation and fairly high summer temperatures. The length of the river is about 30 km. It flows into Lake Vanda.
The water level in the river is subject to strong daily and seasonal fluctuations. The Onyx has several tributaries and flows only during the late Antarctic summer (February, March). During the rest of the time, the river flow looks like a bare ribbon of ice. Sometimes the river cannot reach Lake Vanda for several years. But there are also unique floods; during one of them, in 1984, New Zealand rafters even went down the river.
There are no fish in the river, but there are microorganisms and algae, the bloom of which can be observed.
There are weather stations along the river, and at the mouth of the river is New Zealand's Wanda station
(founded in 1968). Interestingly, the maximum air temperature at the station, recorded on January 5, 1974, was +15.0 °C, which is apparently the temperature record for the entire Antarctica.

So why is there no snow and “multi-million-year-old” ice (in quotes) in these valleys? Why does it snow so little here? It’s hard to believe that precipitation is carried away by winds blowing at a speed of 320 km/h. First of all, the speed of such winds. Or maybe, for some reason, the flood waters could not overflow here and, accordingly, freeze? Or did the temperature of the earth's surface melt all the ice? The temperature of deep waters is 23 degrees. Lake Vanda talks about this.

The English-language wikipedia states that Lake Wanda is a hypermineralized lake with a salinity more than ten times that of seawater, greater than the salinity of the Dead Sea, and perhaps even greater than that of Lake Assal (Djibouti). Lake Vanda is also meromictic, meaning that the deeper waters of the lake do not mix with the shallow waters. There are three different layers of water ranging in temperature from 23°C at the bottom, 7°C in the middle layer and 4-6°C in the upper layers. Those. geothermal lake.

Let's continue our further tour of Antarctica.

McMurdo Station is nearby on the island, on the shore of the bay. The hill looks like a waste heap. 77° 50" 35.70" S 166° 38" 50.51" E

Its height is higher than the level of neighboring mountains

Flat surface of mountains

Why is Antarctica photographed by satellites in winter? Just like the Arctic, by the way. But the panoramio service also has summer photos.

As you can see from the photographs, McMurdo Station is home to a large contingent of researchers. Capital buildings, a lot of machinery and equipment. The station is located on an island in McMurdo Sound. And the central mountain of the island is a volcano:

The diameter of the larger crater is about 500m. But two geologically young craters are located in an older one. It is more than 4 km in diameter.

This is the Erebus volcano. Clouds of steam sometimes escape from the crater. IN this The book says that the volcano last erupted on September 17, 1984. with the release of volcanic bombs.

As you can see, Antarctica lives a vibrant geological life and in some places it is not at all what they show us.