The climate of the Arctic and Antarctica is in many ways similar - in its severity and extreme natural conditions. We will talk about the second of the polar regions today. The climate of Antarctica can be briefly described as the most severe in all the globe. This is due to the peculiarities of the position of the mainland relative to the surface of the planet. In addition to a small area of the northern part of the peninsula, the territory of the continent is located in the Antarctic zone.
Perhaps the southernmost of the earth's continents is the most mysterious place on the entire planet. Its ice-bound expanses are in no hurry to reveal their natural secrets to man. In the extremely cold climate of Antarctica, brave researchers work at special scientific stations located there.
According to scientists, an area of 13,661,000 square kilometers of the continent is covered with ice. The South Pole of our planet lies in the Antarctic region. Its territory does not belong to any of the states. According to international treaties, it is forbidden to develop minerals on it. Only research and scientific activities are allowed.
Climate in Antarctica in antiquity
In the deep past, the Antarctic plate was characterized by less severe weather compared to modern geological time. Nowadays, it is almost impossible to find temperatures above 0⁰С on the mainland. In the Mesozoic era, during the split of the ancient land of Pangea into separate parts, the globe had a milder climate. The mainland of Antarctica in that era was located closer to the equator (that is, to the north). Its surface was covered with tropical forests.
Millions of years later, in the process of moving the plates of the earth's crust of the mainland, the Antarctic plate shifted to the subpolar region.
This movement of a section of the earth's crust to the south led to the formation of an ice sheet on land, which became the main cause of a decrease in temperature throughout the planet. Temperature changes were especially evident in the Southern Hemisphere.
By the time the Antarctic plate moved to the polar region, the surface of the planet had undergone important changes, the essence of which was the closure of the ancient Tethys ocean, the formation of a land isthmus between the plates that make up the territories of the current South and North Americas, and the formation of a circular cold polar current around the Antarctic continent.
The warm conditions of terrestrial weather disappeared, the polar and circumpolar regions were subjected to glaciation. They formed desert regions with harsh and arid weather conditions.
Climate zones of Antarctica
There are two of those. However, some scientists refer to the northern tip of the mainland as a temperate climate zone. In these areas, despite severe weather conditions, there is no polar day and polar night. The geographical position of the mainland is the reason that does not allow the ice cover to melt.
This happens despite the fact that the surface of the planet in this area receives a fairly large amount of thermal solar energy. Peculiar and unique weather conditions can be considered one of the mysteries of the climate of Antarctica.
The nature of the mainland - the main features
This continent is located above all others above sea level. This circumstance is connected with the most powerful shell of ice covering the surface of the mainland. Its cover reaches a thickness of 4.5 thousand m. Such a grandiose ice shell affects the climate formation of the entire planet.
What is the most extreme climate in Antarctica? Particularly harsh conditions are in the inland regions. Precipitation is practically non-existent. Their total volume is no more than 50 mm per year (on the rest of the planet, precipitation falls in an annual volume in the range from 100 to 250 mm). The temperature of the deep regions often drops to -64 ⁰С in winter and -32 ⁰С in summer. The minimum temperature recorded on the globe was about 90 ⁰С. This indicator was recorded by researchers at the Vostok station.
The deep regions of the continent are characterized by strong winds with speeds reaching 80-90 m/s. The wind blowing from the inland region intensifies as it reaches the coast.
What climate in Antarctica can be called relatively gentle? The subarctic zone is characterized by some softness. Part of the northern tip of the land falls there. Precipitation in excess of 500 mm per year is formed in this belt. In summer, the air temperature here rises to zero.
The subarctic climate zone has a less powerful ice cover. In some places the landscape consists of rocky islets covered with lichens and moss. The influence of the inner Arctic regions on the coast of the mainland leads to their unsuitability for human existence.
On the radiation balance of the continent
For a long time, scientists have been research work studying the harsh climate of the Arctic and Antarctica. The project was related to the compilation of the land radiation balance. They measured the radiation received from the sun, as well as reflected from the ice and snow surface. As a result, it was found that about 80% of solar energy is reflected from the surface of the snow cover, and the remaining 20% is absorbed by the earth with transformation into heat, most of which is dissipated in the form of radiation into space.
Scientists have calculated that the southern continent uses no more than 5% of the energy received from the Sun for its own needs. Such an energy balance is inherent in Antarctica only in the summer (November - February). In winter, the duration of which is from March to October inclusive, the surface of the Earth there does not receive at all solar heat. At the same time, thermal energy is lost with the same intensity as in summer. Winds blowing from the tops of the mainland mountains contribute to the decrease in temperature.
Polar day and night in the Southern Hemisphere
As in the Northern Hemisphere, there are periods of polar day and night in Antarctica. According to astronomical calculations, December 22 is considered the day of the summer solstice, and June 22 - the winter. The sun (according to astronomers) these days "must" be only half hidden (and, accordingly, shown) relative to the horizon. The phenomenon of astronomical refraction, which consists in the refraction of light rays in the atmosphere, leads to an increase in the duration of observation of a celestial body.
We can only talk about the change of night and day in the southern latitudes, which is familiar to all of us, only in the autumn and spring periods. In winter, the mainland plunges into the conditions of the polar night, in the summer there is a polar day around the clock.
Summer in Antarctica
On the coast of the mainland, the climate of Antarctica is characterized by warm periods lasting a week or more. The underlying surface is not supercooled much. Instead of radiating heat into the atmosphere, it absorbs it from there at that time. The radiation balance takes on a positive value with an increase in the temperature of the medium.
Air circulation carries to the shores of the mainland, in addition to heat, also cold air masses - from the depths of the land. Descending from the ice sheets, they partially warm up. The winds circulate in a very peculiar way. Most often during the year it turns out to observe their movement from the same sector. Depending on its location, extremely fast and drastic changes weather.
Scientists of two scientific stations - Amundsen-Scott and Vostok - are monitoring the climate of Antarctica in the center of the continent. Their recorded average winter temperature internal areas - about minus 60-70 ⁰С, summer - minus 25-45 ⁰С. The highest temperature was recorded in 1957 at the Vostok station and amounted to -13.6 ⁰С. This temperature jump was explained by a sharp invasion of the territory of the mainland by an oceanic cyclone.
The Amundsen-Scott station is located at the South Pole. Due to the relative proximity of the coast, the climate here is relatively mild. In summer, there is a large amplitude of temperature fluctuations compared to winter.
Is it warm on the mainland?
In the coastal regions of Antarctica (especially on its peninsula), the temperature in summer can rise to +10 ⁰С. The warmest month there is January. The temperature on the coastal slopes at this time is +12 ⁰С.
In July, the coastline area has temperatures from -8 ⁰С (peninsular zone) to -35 ⁰С (ice shelf). The average annual wind speed is about 12 m/s, but under certain conditions, air masses are able to move at a speed of 90 m/s. The humidity of the air masses descending from the mountains is 60-80%. In some areas, it can significantly decrease.
In rare cases, light cloudiness with precipitation in the form of snow can be observed in the peninsular zone. On the slopes in the lower region, the amount of precipitation is greater - this figure reaches 600-700 mm, at the foot - 400-500 mm.
The combination of a large amount of precipitation with powerful air currents leads to the appearance of frequent snow blizzards in this region of the mainland.
Antarctic currents
The oceans have a warming effect on the mainland, due to which the temperature on the coast rarely drops below -40 ⁰С. The average annual value of the indicator is -10-12 ⁰С in coastal areas and up to -5 ⁰С in the north of the Arctic Peninsula.
In areas of a few oases, the surface can warm up to a temperature of +2 ⁰С, and on some rare days - to even higher numbers. At Mirny station, cases of heating of air masses to a temperature of +8 ⁰С were sometimes recorded. The total duration of such periods is quite short and amounts to no more than 1000 hours during the Arctic summer.
Oases in Antarctica
The oases existing on the mainland (the largest of them, the Dry Valleys) occupy a relatively small area. In summer, water in its liquid phase can be observed in them. In some places, lakes with fresh and salt water have been identified. The area of each such oasis (and they can be coastal, mountainous and coastal) ranges from tens to hundreds of square kilometers.
Research stations are being built on their territory. The total area of all the oases of the mainland, according to approximate estimates, is about 10,000 square meters. km. The increased temperature values of these areas are explained by the ability open ground to increased absorption of solar radiation. Occasionally, the rocks warm up to a temperature of +20 ⁰С. The record was the heating of the surface to a temperature of +30 ⁰С recorded at Mirny station.
What does Antarctica look like in summer?
The heated ground causes the snow to melt quickly. In conditions of dry air, the resulting moisture evaporates rapidly. As a result, both the soil and the air of the oases remain dry. In terms of their climate, these territories resemble a cold, dry desert.
The layer of air closest to the ground is heated from the rocks with the formation of ascending air currents. As a result, cumulus clouds can be observed. The effect persists at altitudes up to 1 kilometer.
Climate of Antarctica and fauna
Surrounding the mainland, the Southern Ocean is one of the most amazing ecosystems on Earth. It is home to a huge number of the most incredible creatures. Most of them are migratory, since the climate of Antarctica does not favor permanent residence or wintering. But some species (called endemic) can only be found on this mainland. Their peculiarity is in the ability to adapt to the harsh natural environment.
Representatives of the local fauna are not at all afraid of people. Researchers have the opportunity to get close to wild animals in order to better study the Antarctic fauna. At the same time, one should take into account the ban on touching wild animals prescribed in the Antarctic treaties.
Let's briefly talk about the most interesting representatives continent.
mammals
The blue whale can be called the largest animal that lives on our planet. Its weight is over 100 tons. This is a truly impressive natural creation. Despite their size, whales are truly elusive. They are characterized by a highly developed intellect, freedom of movement and a complex social life.
They belong, like dolphins, to the order of mammals (the name is cetaceans), that is, they are close relatives of people, elephants, dogs and cats. Those who spend at least part of the time of the year near the coast of the continent are called whales of Antarctica. Apart from blue whale, we can talk about the southern smooth whale, sei whale, fin whale, humpback whale, sperm whale, killer whale, southern minke whale, Kerguelen fur seal from the eared seal family.
The last mammal in appearance and manner is somewhat similar to a large dog. Such seals belong to the pinnipeds and can pull the rear flippers under the body, lifting the front flippers own weight, in connection with which their flexibility on land is much higher than that of their relatives. They are found mainly on the subarctic islands.
Another Antarctic mammal is the leopard seal. This name he received because of the spotty color of the body. This is one of the largest predators of the continent. Sea leopards feed on almost any animal - squid, fish, birds, penguins, and seal cubs. They are immersed in water for no more than a quarter of an hour and mostly live near open water. They swim at speeds up to 40 km/h.
Who else can be found on the mainland
Crab-eating seals can be attributed to the category of the largest Antarctic mammals. Sometimes they lie large groups, giving the impression of a flock, although in general they are solitary animals. Despite the name, they do not eat crabs. 95% of their diet is Antarctic krill. The rest is fish and squid. The teeth of crabeaters, shaped like a sieve, are adapted for catching krill in the water.
Weddell seals can be found in Antarctica. Unlike previous representatives of the fauna, their diet is mainly fish and squid. They are excellent divers, able to dive to depths of up to 600 m and spend more than an hour underwater. It is very difficult to estimate the size of their population due to their habitat on drifting ice and close to the Arctic Circle.
About southern sea elephant one can speak of the largest of the seals. Its diet is mainly squid and crayfish. It also moves great underwater with deep diving. It is found throughout the continent, even deep in the south.
Birds of Antarctica
A typical representative is the Antarctic tern from the tern family - a bird of small size (31-38 cm) with a wingspan of 66-77 cm. It has a black or dark red beak and light plumage with a black cap on its head. Terns feed on krill and fish, noticing prey from the air and diving after it into the water.
The only representative of the cormorant family that can be found in Antarctica is the Antarctic blue-eyed cormorant. Feature appearance - a yellow-orange growth near the base of the beak and a bright eye color. Its body length is 68-76 cm.
The cormorant feeds mainly on fish. Sometimes a whole flock of birds forms a "trap" for food, diving into the water and helping each other to get it. They can dive to a depth of over 100 meters. During swimming, their wings are tightly pressed to the body, and webbed feet are actively working.
Another representative of the bird world of the mainland is the white plover, leading a terrestrial lifestyle. When walking, it is characterized by nodding its head like doves. It does not have webbed feet for swimming. The food of the plover lives on the ground. Characteristic behavior is omnivorousness and a tendency to steal food (fish and krill) from penguins. Sometimes it can feast on eggs and chicks.
Other representatives of the bird world
Among other representatives of the flying fauna of the mainland, one can mention the Cape dove from the petrel family, snow petrel, wandering albatross, southern polar skua, southern giant petrel.
Flightless birds should also be mentioned - the emperor penguin (the largest in the world, average weight it is about 30 kg), as well as the king penguin (the second largest) 70-100 cm tall, with bright plumage, feeding on fish and squid. Another type of penguin is the subantarctic (also known as gentoo). Its sign is a wide white stripe on the head and beak.
Other representatives of the fauna
Antarctic krill is a small crustacean that lives in large groups. Its density per cubic meter is sometimes 10,000-30,000 individual individuals. Its food is phytoplankton. Krill can grow up to 6 cm in length and weigh about 2 grams. Life span is about 6 years. It is the basis of the Antarctic ecosystem and the most common representative of biomass.
The only non-flying insect found in Antarctica is known by the Latin name Belgica antarctica. It is 2-6 mm long, black in color. The insect can withstand changes in the Antarctic climate and can exist without oxygen for 2-4 weeks, but at temperatures below -15 ⁰С it dies.
The climate of any place on earth, as well as climate of Antarctica, is formed under the influence of three main factors: solar radiation, atmospheric circulation and geographical conditions of the place itself. Mainland Antarctica.
Mainland Antarctica
It is known that where the earth receives a lot of solar heat, as, for example, at the equator, it is always hot; where air currents bring moist sea air, it is damp; on the top of a high mountain it is cold and snowy, and at its foot there is eternal summer. But there are places on Earth, and even a whole continent, where in summer almost as much solar heat falls on its surface as in the subtropics. However, here not only grapes do not ripen, but even grass does not grow. The ground is covered with a thick layer of snow and ice that does not melt even in summer. This is what it is mainland Antarctica. On a clear summer day on the coast, each square centimeter of the surface receives about 0.5 calories of solar heat per minute. The amount of incoming heat in one summer month is almost 20,000 calories (20 big calories). This is one and a half, even two times more than at the same latitudes of the northern hemisphere, and only slightly less than what the cotton fields near Tashkent receive. If all this heat were spent here on melting, then in one summer its power would decrease by ten meters, i.e., in 10-15 years in the region Mirny(located on the coast of Antarctica) the ice would have completely melted.
Glacier on the coast of Antarctica. In the depths of the mainland, for example, at the station Pioneer, even more solar heat enters the snow surface in summer, but the snow does not melt. Eternal frost and blizzard reign here. Why is this happening? Where does all this huge amount of solar energy go? After all, according to the law of conservation of energy, it should not disappear anywhere!.. The mystery of the climate of Antarctica
It was the main climate mystery of Antarctica. To unravel it, the members of the first Soviet Antarctic expedition, which was based at Mirny and Pionerskaya stations, continuously monitored the inflow and outflow of solar heat throughout the year, that is, they kept a kind of "accounting" of solar radiation. Most of this work was carried out by special self-recording devices - "electromechanical" accountants of the Sun ". They continuously recorded how much heat comes from the sun, how much is reflected and radiated by the snow-ice surface of Antarctica, and, finally, what kind of radiation balance is obtained.Climate research in Antarctica
results climate research in Antarctica exceeded all expectations. It turned out that about 80-82% of the sun's rays falling on it are reflected from the snow-ice surface of Antarctica, like from a mirror, in winter and summer. This huge amount of solar energy almost completely goes back into the world space.
Snow and ice climate of Antarctica. Well, where do the remaining 18-20% of the sun's rays that fall on the ground go? They are absorbed by the earth's surface and converted into heat. But the surface of Antarctica cannot save this, already assimilated heat. Almost half of it (more than 10% of the total radiation) is lost by thermal radiation, and only the remaining 8-10%, and on Pionerskaya even 5%, Antarctica spends for its needs. But it happens in the summer(from November to February). in winter(from March to October) the surface of Antarctica receives almost no solar heat at all. And the radiation of heat from its surface occurs continuously. Heat loss every month due to radiation in winter is 2-3 large calories. Calculations show that due to radiation, the surface of Antarctica would cool by about 5-6 ° per hour. However, this does not happen. Only once, while exploring the climate of Antarctica, did the members of the first expedition, which arrived in Antarctica in January 1956, witness such a sharp drop in temperature. It was August 20 - in the middle of the harshest month of winter. The sewage wind (the wind flowing from the snowy peaks of the mainland), which usually begins in the evening, suddenly subsided. It quickly cleared up, and the temperature dropped by 10° within an hour and a half, reaching -40.4°. It was the lowest temperature in Mirny. Then the wind blew and again it became warmer on the southernmost land. Influence of air circulation on the climate of Antarctica
So the movement air circulation saves the surface of Antarctica from continuous cooling. The influence of atmospheric circulation on the formation of the climate of Antarctica is unusually great. In Mirny, for example, there was not a single winter month so that the air temperature with the arrival of the sea air mass would not rise to -3 -6 °. So, for example, from 29 to 30 April of the year under study, during the day the temperature increased from -25 to -8°. Such warming spread even to Pionerskaya, where during the same day the temperature increased from -50° to -30°. Warm periods in winter in Antarctica sometimes last a week or more. The transfer of heat from the air to the underlying surface in this case occurs not only by air vortices, but also by thermal radiation of the atmosphere. The surface of Antarctica, instead of radiating heat, begins to receive it from the atmosphere, the radiation balance becomes positive and the temperature begins to rise rapidly. Due to the circulation of the atmosphere, not only heat, but also cold is brought to the shores of Antarctica. This happens when the air does not move from the sea, but from the depths of Antarctica, flowing down the slope of the Antarctic Plateau.
The cold off the coast of Antarctica is not a hindrance to penguin hunting. Just as water, after a heavy rain that has fallen on a mountainside, flows down to the foot, rapidly accelerating its movement under the influence of gravity, so cooled, denser air descends along the long slope of the glacial plateau of Antarctica. It moves faster and faster every minute, often reaching the strength of a hurricane near the coast. However, unlike the flow of water, the air flowing down the slope is continuously heated (for every 100 m of height by 1 °), so the temperature with which it comes to the coast, although low, is much higher than that which would be here if there would be no wind. This is confirmed by data from remote stations. So, for example, on a clear day on August 12, when a storm was raging in Mirny, 13 km away on fast ice (this is the name of the ice above the surface of the water, firmly fused with the continental ice), where the influence of the sewage wind did not affect, there was calm and temperature air was 11° lower than in Mirny. Waste wind in Antarctica is a "cold" hair dryer. The air, moving from the central regions of Antarctica, as well as with an ordinary hair dryer, heats up and, moving away from the saturation point, becomes drier. However, due to relatively low altitudes and very low initial temperatures, it cannot get very hot, so it comes to the coast not warm, but cold. For example, such a case: the air moves from Pionerskaya station to Mirny. The height difference between these stations is about 3 km. If the air temperature on Pionerskaya was -50°, then it will come to Mirny with a temperature of -20°, i.e., still very cold. The circulation of the atmosphere over Antarctica is completely peculiar. In coastal areas, and even far inland, the winds blow from almost one sector all year round (from north-northeast to south-southeast), but depending on whether they blow closer to the eastern edge of the sector or to south, the weather changes very sharply. East winds are associated with the movement of the cyclone and carry heat, while southeast winds are associated with the flow of cold inland air and carry cold. Influence of terrain on the climate of Antarctica
On the climate of Antarctica affects and terrain influence. Here, in one area, a severe storm with a blizzard and calm weather can be observed simultaneously, although there are no big differences in the relief at all. This is how the participants of the expedition describe the trip to Mirny.In early August, we had to go to the inspection station at one of the remote stations, 4 km from Mirny, and, like Mirny, located not far from the coast. The weather was clear, a weak southeast wind (5 m/s) was blowing. Having left the transmitting radio station, we saw ahead, as it were, a veil of fog, which thickened and rose as we approached the sea. A few minutes later the all-terrain vehicle drove into the strip of snow. Thousands of small streams moved near the surface of the ice, merging into separate streams. The farther we moved, the streams became denser, as if clinging to one another, until they merged into a huge milky white river. And now we are crossing the "river" ford. The level of the blizzard is getting higher, soon it closes the tracks of the all-terrain vehicle, and then the windshield. You have to drive blindly. In order not to go astray, we get out on the cabin. The station is not visible, only the State Flag fluttering on the mast is visible. When we arrived at the station and got out of the car, it was impossible to walk, our feet slipped on the ice polished by blizzards, and the wind instantly knocked us down. There was a storm here. The wind speed was three times stronger than in Mirny. And at the station, located on fast ice, at that time it was quite quiet. Free from watch people went skiing. A nearby colony of emperor penguins has begun to hatch chicks.The influence of the area especially affects temperature regime . For example, unusually low temperatures at Pionerskaya station (69°44" S), located at an altitude of about 3 km, are striking. The average annual air temperature at this station is below 38°. Interestingly, at approximately the same latitude, but in the northern hemisphere of Kola station (near Murmansk, 68°53" N), the mean annual air temperature is -5°. At Pionerskaya station the highest temperature was -13°C, and at Kola station +32°C. Many such examples could be cited.
The climate of Antarctica depends on the rarefied air
severity Climate of Antarctica, especially in inland regions, is also exacerbated rarefied air caused by high altitudes above sea level.
Harsh climate of Antarctica. At Pionerskaya station, for example, the air pressure is one and a half times lower than at Mirny. With such pressure, any rapid movement disrupts the rhythm of breathing, a person quickly gets tired even from a slight physical exertion. Undressing before going to bed, sitting on a bunk, and then climbing into a sleeping bag, caused the same heartbeat as after a long and fast run. It is especially difficult in such conditions to perform heavy physical work. There was such a case during the expedition. Immediately after arriving at Pionerskaya, they had to dig a room in the dense snow to extract hydrogen, which was necessary for the production of pilot balloons and radiosondes. It was possible to dig a room with a bulldozer, but how to make a roof? At hand, except for a few fragile rails and two or three drill pipes, there was nothing. Having laid them as a ceiling, they began to cover the room with a tarpaulin. The roof was fragile, but held. We proceeded to the equipment of the gas generator. We finished the work at 2 am (it was a round-the-clock spring day). After a short rest, we decided to start producing hydrogen. What a disappointment it was when, having come to the gas generator, they saw that a huge snowstorm had blown up on the roof. The roofs have caved in. Climbing into the room was dangerous. Soon all this mass of snow collapsed, filling up all the equipment. The snow had to be thrown out by hand, as the bulldozer could break the instruments. This is where the low pressure comes into play. Throwing each shovel of snow to a height of 2-2.5 m caused shortness of breath. After making several throws, people fell down. And then there was the continuous blizzard, nullifying the results of all the labors. To make reliable ceilings, it was necessary to dismantle the flooring of the only tractor sledges at the station. But the sleigh was far away. The tractor didn't work. The boards had to be torn off the sled and carried on oneself. They walked slowly, carrying two boards. Here, throwing the boards aside, the radio operator Ushakov fell into the snow. He was carrying three boards, and his breath caught. Having thrown off the boards, each of us, even Zotov, who squeezed more than 90 kg on the dynamometer with one hand, stopped exhausted or lay down on the snow under a prickly snowstorm. But what was the joy when a few days later, for the first time in the history of science, a radiosonde rose in the depths of Antarctica. A regular study of the high layers of the atmosphere inside the ice kingdom began in order to study more thoroughly the climate of Antarctica.These were the main patterns of formation of the climate of Antarctica, these are the main reasons for its severity. But the influence of the atmosphere on the climate of Antarctica was not the only mystery, and was not limited to climate issues. Before the eyes of researchers, such phenomena arose that even the venerable scientists of the world could not answer. Many of these phenomena have not even been observed before. For example: "disappearance of the stratosphere", snow tornadoes (blood clots); colored halos and false suns, a winter rainbow arched backwards; haze over snow, haze of snow (fog); ice cloud near the ground; colored drifting snow, snow fountains-geysers, summer clouds in the depths of Antarctica, a whitening effect, sparks flying from the hands, a neon light bulb that lights up at the touch of a finger, and much more. Each of these phenomena is observed at a certain time of the year, therefore, in order to unravel them, one must at least mentally imagine these conditions.
Antarctica is the sixth continent, the last of the discovered continents. Due to the extremely harsh conditions, it is inaccessible to most. However, people do not really want to come here. Only trained researchers survive here for quite a long time. Hurricane winds, low temperatures, endless expanses of ice and snow - that's what Antarctica is. The climate of the continent is primarily determined by geographic location mainland.
Place on the globe
The position of Antarctica is the reason why it has remained hidden from the watchful eyes of navigators for so long. The sixth continent is located in the Southern Hemisphere, in the polar region. In addition to the distance, it is separated from the rest of the continents by drifting ice, which was an insurmountable obstacle for the ships of past centuries.
At some distance from the center of the mainland, there is relative inaccessibility and the absolute pole of cold - two more points that Antarctica can boast of. The climate of the continent in general terms becomes clear already from their names.
Temperature
The lowest mark to which the thermometer fell in Antarctica is -89.2 ºС. Such a temperature was recorded in the area of the then Soviet Vostok station. Here is the absolute pole of cold.
In the central zones of the continent there are no positive temperatures even in short summer months. From November to February, when the warm season comes, the air can warm up to -30 ºС or -20 ºС. On the coast, things are different. Here the temperature in the summer months rises to 0 ºС and sometimes even higher.
Sunny but cold
The climate features of Antarctica are associated with a fairly large amount of energy coming here from our star, and at the same time low temperatures. This discrepancy is explained by the high reflectivity of ice. During the short summer months, the sun shines from an almost cloudless sky almost non-stop. However, most of the heat is reflected. In addition, during the polar night, which lasts half a year on the continent, Antarctica cools down even more.
Hurricanes
The severity of the climate of Antarctica is explained by another of its features. The so-called kabatic, or stock, winds blow here. They are formed as a result of the difference in surface and air temperatures. Also the reason for the formation of winds is the dome-shaped configuration of the ice sheet of the continent. The surface air layer cools, its density increases, and under the action it seems to flow towards the coast. The thickness of such a mass is on average 200-300 meters. It carries a large amount of snow dust, which greatly impairs visibility in the area where the wind occurs.
The speed of movement of air masses depends on the degree of steepness of the slope. The winds are strongest in the coastal area with a slope towards the sea. They blow for quite long periods. Arctic winter is the time of maximum raging from April to November with almost no break. From November to March the situation improves somewhat. Winds arise only when the Sun is low above the horizon, and at night as well. With the advent of summer, due to the increase in surface temperature, the coast becomes quiet.
Antarctica, whose climate is quite severe even in the summer months, is inaccessible to airplanes and other aircraft for eight months as a result of the activation of hurricane winds. Polar explorers wintering at this time, in fact, remain cut off from the outside world.
"Native people"
Such a harsh climate, meanwhile, did not make Antarctica completely uninhabited. There are birds, insects, mammals and even plants. The latter are represented mainly by lichens and low-growing grasses (not higher than one centimeter). Mosses are also found on the continent.
There is not a single completely terrestrial mammal species on Antarctica. The reason for this lies in the sparse vegetation: in the central zones of the mainland there is simply nothing to eat. The most famous animal of the continent is the penguin. Several species nest here. Some settle only on the islands, others have chosen the coast.
Antarctica, whose climate is detrimental to many organisms, does not scare away seals, as well as sperm whales, killer whales, and southern minke whales. Of the birds other than penguins, icy expanses are native to skuas and petrels.
The harsh Antarctic climate is unsuitable for human life. However, this does not prevent scientists from actively exploring the continent: a fairly large number of polar stations have already been located on its territory. Every year, researchers strive here to overcome many secrets of the mainland and nature in general.
Causes of the severity of the climate of Antarctica
Remark 1
Antarctica is a continent of harsh climatic conditions, hurricane-force winds, endless expanses of ice and low temperatures, the climate of which depends primarily on its geographical location.
This highest continent is located at an altitude of 2000 m above sea level, and its central part reaches 4000 m.
Figure 1. Climate conditions in Antarctica. Author24 - online exchange of student papers
Most of the height falls on a permanent ice sheet that hides the continental relief.
The climatic features of the mainland are associated with a large amount of incoming solar energy, and at the same time with low temperatures.
The lowest temperature mark was recorded at the Vostok station and amounted to -89.2 degrees - the station is the absolute cold pole of the Southern Hemisphere.
With the advent of the summer period, the air temperature rises to -30, -20 degrees. On the coast, it is much warmer than 0 degrees, and sometimes even higher.
Despite the fact that in summer the mainland receives a large amount of heat, about 80-82% is reflected from the snow-ice surface and goes back. The remaining amount of heat is absorbed by the surface and converted into heat, but half of it is lost by thermal radiation.
In winter, the mainland does not receive solar heat at all, while heat radiation from its surface occurs continuously and the surface cools even more.
Another reason for the severity of the Antarctic climate is katabatic winds, which are formed as a result of the temperature difference between the surface of Antarctica and air, as well as its dome-shaped configuration.
Such winds blow almost without interruption from April to November.
The terrain also has its influence on the climate, although there are no big differences in the relief, but in one area there can be a strong storm with a snowstorm and calm at the same time.
The circulation of the atmosphere over Antarctica is very peculiar. All year round in the depths of the mainland and in coastal areas, winds blow from one sector - from the north-northeast to the south-southeast.
True, if they blow closer to one edge, for example, to the south or east, then the weather changes very dramatically.
Due to the circulation of the atmosphere, both heat and cold are brought in, and this happens when air moves from the depths of the mainland, flowing down the slope of the Antarctic plateau.
East winds carrying heat are associated with the movement of the cyclone, and southeast winds are associated with the runoff of inland cold air.
Another reason that affects the climate of the mainland is the rarefaction of the air, since the height above sea level is significant. Especially rarefied air affects the severity of the climate in the interior.
Climate of Antarctica
The mainland lies in two climatic zones - subantarctic and antarctic.
The northern tip of the Antarctic Peninsula is sometimes referred to as the temperate zone. Within its limits there is no polar day and night, but, despite this, the conditions of the peninsula are very harsh.
On its coast, the average annual temperature is -10 degrees. At its northern tip, the air temperature rises to -5 degrees.
In the northwestern part of the peninsula, in coastal oases, the average January temperature is above zero and is +1, +2 degrees.
Positive temperatures here can be observed at any time of the year.
Twenty-degree winter frosts may be replaced by thaws. The maximum temperature of +14 degrees recorded here was observed at the height of winter - in July on the east coast in 1958.
On the northwestern coast of the peninsula, precipitation is 700-800 mm, and sometimes even up to 1000 mm. On average, about 120 mm falls on the mainland per year, in the depths of the continent their number decreases and only 30-50 mm falls per year.
The most severe conditions have formed in the inland regions of Antarctica. The winter temperature here drops to -64 degrees, and the summer temperature rises to -32 degrees.
In the depths of the continent are formed strong winds, the speed of which reaches 80-90 m/s. Reaching the coast, the wind intensifies.
Around Antarctica, intense cyclonic activity develops over the ocean.
In the west of the mainland coastline well indented and there are bays that go far into the land, it is here that cyclones penetrate the mainland. Their penetration to the east of the mainland is rare.
The Antarctic coast is an area where the climate is moderately humid and relatively mild. In summer, the thermometer sometimes rises above zero, and the snow begins to melt intensively.
On the coast of Antarctica, the air is noticeably warmer, here the warming effect of the ocean affects. Despite the fact that coastal waters are covered with ice and have a temperature close to the freezing point, the water is warmer than air and is constantly exchanging heat with it.
The temperature on the coast does not fall below -40, -45 degrees, and the average annual temperatures are -10, -12 degrees.
The temperature of the coast in summer is -4 degrees. Stock winds here reach speeds of 15-20 m/s. With katabatic winds, clearings are observed.
AT summer time sunny weather on the coast of the mainland contrasts sharply with gloomy clouds over the ocean. Up to 500 mm of precipitation falls on the eastern coast, and up to 700 mm on the western coast.
The most severe conditions have formed in the inland regions of Antarctica.
Inland climate
In the inland regions of Antarctica climatic conditions the most severe on the planet.
Regular meteorological observations are carried out here at the Amundsen-Scott and Vostok scientific stations. At Fuji Dome Station, a minimum temperature of -91.2 degrees was recorded.
The average winter air temperature is -60, -70 degrees, the summer temperature rises to -45, -25 degrees.
The Amundsen-Scott station was founded at the South Pole in 1956 and is gradually drifting towards the coast. This is due to the fact that the glacier slowly slides from the dome-shaped mainland from the center to the edge, where it breaks off under its own weight and enters the ocean.
At this station in winter, the thermometer reaches -60 degrees, and in January it does not fall below -30 degrees.
The climate at the Amundsen-Scott station is slightly milder compared to the Vostok station.
Figure 2. Inland climate. Author24 - online exchange of student papers
The inland Vostok station has existed here since December 1957, and during the entire existence of the station, the thermometer showed -13.6 degrees only once - it was the warmest day, December 16.
Such a high temperature was associated with the invasion of cyclones from the ocean to the mainland, which is extremely rare.
The minimum temperature from April to September at Vostok station is below -80 degrees, and the average monthly temperature is below -70 degrees. But, in mid-April and at the beginning of the third decade of September, it is above -70 degrees.
Winter temperature fluctuations are less than summer ones.
Remark 2
Thus, the lowest absolute minimum air temperatures are observed at the stations:
- "Pole of Inaccessibility"
- "Kun-Lun"
- "East",
- "Vostok-1",
- Fuji Dome.
In the central regions of Antarctica, very little precipitation falls during the year, which is a common feature of the climate of this region.
Precipitation comes in the form of "diamond dust" - these are ice needles, as well as frost. The wind speed here is small, increasing with approach to the continental slope.
Polar scientists and weather forecasters jokingly call Antarctica the “weather kitchen” for the entire planet. Experts know exactly when the conditions are more or less favorable for traveling in the vicinity of the South Geographic Pole. Ordinary people often lost in conjecture: “What is the warmest month beyond the Antarctic Circle? Are there positive temperatures in Antarctica? It is not easy to figure out what is going on in the "kitchen of the weather", everything is different here, not like on other continents.
The white continent becomes more accessible
Until the 20s of the 19th century, scientists and travelers argued about the existence of land near the South Pole. Many believed the famous navigator J. Cook, who declared that the territory south of 71 ° S was inaccessible. sh. The Russian expedition to Antarctica on the ships "Vostok" and "Mirny" on January 20, 1820 discovered unknown lands, despite many insurmountable obstacles. After 120 years, the first excursions to the waters of the Antarctic began, another 50 years were needed for the development of a new tourist destination.
Hundreds of adventurers go every year to the white continent. Expeditions and tours are held during the most favorable period of the year in the Southern Hemisphere. What is the warmest month in Antarctica? - the townsfolk ask in bewilderment. Of course, at school everyone was taught the climate of the southern continents, where our winter is summer. It is difficult for many to say exactly which month is better for a tour to the South Pole.
Antarctica and the Arctic - two opposites
Let us briefly dwell on geographical terminology. The land in the south owes its name to the Arctic. This word, denoting the northern polar latitudes of the Earth, of Greek origin, is given according to the position. sh. blocked by the cold waters of the ocean, ice and snow.
The territory in the south, opposite the northern polar region, was called the "Ant (and) Arctic", the mainland - Antarctica. The South Pole is located almost in the center of the continent. Geographic coordinate this point - 90 ° S. sh.
The southernmost and coldest continent
Severe climate south of latitude 70°S. sh. called "subantarctic" and "antarctic". During the year, areas of the surface free from snow and ice warm up better on the coast, in oases. In winter, on the coast and in the northern part of the Antarctic Peninsula, the temperature is comparable to arctic belt(from −10 to −40 °С). In the summer in Antarctica, you can find many islands of land among the icy silence, where the thermometer rises above 0 ° C.
Features of the climate of Antarctica:
- Winter lasts from June to August, this is the coldest period.
- average temperature July is between -65° and -75°C.
- Summer comes in December and lasts until February.
- The temperature in the continental part rises from -50 to -30 °C.
- The warmest month in Antarctica is January.
- The polar day lasts from September to March. The sun remains above the horizon, warming the surface more.
- The night lasts for almost half a year, illuminated by bright flashes of the aurora borealis.
Inland climate
Antarctica is a continent where regular meteorological observations began later than on the inhabited continents. For the last 50-60 years, the data obtained at stations in the mainland and coastal parts of the white continent have received special attention from weather forecasters. The coldest regions are the southeastern ones, where the average annual temperature is about -60 °C. The temperature maximum in the area of the Vostok station is -13.6 ° C (December 16, 1957). Average monthly temperature from April to September - below -70 ° С.
The weather at the South Pole is a bit milder, this part of the mainland is closer to the coast. Meteorological information at a point with a coordinate of 90 ° S. sh. collected by employees of the American Amundsen-Scott station, named after the Napoleon of the Polar Countries, Norwegian Roald Amundsen and another discoverer of the South Pole, an Englishman. The station was founded in 1956 at the South Pole and gradually “drifts” towards the coast. Antarctica has the shape of a dome, the glacier slowly slides from the center to the edges, where its pieces break under their own weight and fall into the ocean. In winter, near the Amundsen-Scott station, the thermometer shows -60 ° C, in January it does not fall below -30 ° C.
Weather on the coast of Antarctica
In summer, on the shores of the oceans and seas washing the southernmost continent, it is much warmer than in continental regions. Over the Antarctic Peninsula, the air warms up to +10 °C in December-February. The average January temperature is +1.5 °C. In winter, in July, the average monthly temperature drops to -8°C on the coast of the Antarctic Peninsula, to -35°C - in the area of the margin of the Ross Glacier. One of the climatic anomalies of the mainland is cold katabatic winds, the speed of which reaches 12-90 m/s on the coast (hurricanes). Rain, like high temperatures, is rare in Antarctica. Most of the moisture reaches the continent in the form of snow.
Antarctica is a "multipolar" continent
"Pole of inaccessibility" - this is the name that Russian polar explorers came up with for their station. The Soviet expedition to Antarctica carried out scientific research beyond the 82nd parallel in the most difficult for movement high-mountainous region of the mainland.
On the mainland there is a "Pole of Cold" - this is the area of the research Antarctic station "Vostok", created in Soviet time. Here, with the help of ground-based measuring equipment, the lowest air temperature in the history of meteorological observations was recorded: -89.2 ° С (1983).
Researchers from the United States, armed with satellite data, tried to challenge the "record" of the Russian station. In December 2013, the Americans reported that they were in the area of the Fuji Dome station, owned by Japan. The absolute minimum temperature for Antarctica was -91.2 ° C, which was found out using a satellite.
Antarctica is the prototype of a "multipolar" world without borders and an arms race. The international legal regime was introduced here in 1961. The mainland and the parts of the oceans adjacent to it do not belong to the states parties to the treaty and observer countries, they can only conduct scientific research.
What to do in the warmest month in Antarctica and in the Arctic
Exploration of the North and South Poles, the white continent in the south and the ice of the Arctic has always been the lot of the brave and patient. Today there are quite a few people on the planet who have been to Antarctica more than 100 times. Some carry out scientific research, others provide transport accessibility, security, and provide medical care.
There are more and more people who go beyond the Antarctic Circle in search of fantastic experiences. Tours to Antarctica at first glance seem like pure adventurism. In fact, all flights, sailings and excursions are prepared at the highest level. Polar scientists act as consultants, icebreakers and research vessels are used.
The peak of the "tourist season" in the polar regions
The high cost of a flight or sea cruise to the North and South Poles, the high costs of organizing expeditions do not stop modern adventurers. Let's rephrase the famous statement of the foreman from the film "Operation" Y "and other adventures of Shurik." Now dozens of ships with tourists "plow the expanses" of the Arctic and Antarctic. The day is not far off when there will be many more of them. The "high season" at the South Pole begins in December and lasts until January. At this time, the hemisphere is better illuminated by the Sun, the height of summer comes.
The weather at the North Pole is warmer than at the South. The climate also depends on the small angle of inclination of the Sun above the horizon, the strong reflectivity of snow and ice. The temperature in winter in December-February and in summer in June-August is much higher than in Antarctica. The average winter temperature at the North Pole is -30°C. Often there are thaws (−26 ° C), cold snaps (−43 ° C). The average summer temperature is around 0°C.
Are there any "white spots" in Antarctica?
The Age of the Great geographical discoveries completed in the 1920s by S. V. Obruchev, the son of the scientist, traveler and writer V. A. Obruchev (“Geology of Siberia”, “Sannikov Land”). Sergei Obruchev explored the last "blank spots" in Eastern Siberia and Chukotka. By that time, a significant part of Antarctica was still little studied.
Gradually, the researchers found out the thickness of the glacier and the features of the under-ice relief, collected detailed meteorological information. Many "white spots" on the sixth continent have been closed, but the south polar continent still holds many mysteries and secrets. For avid travelers, a warm month in Antarctica is a new experience, an opportunity to see rare representatives of the animal world and take unique photographs.
Are expeditions to the Antarctic Circle dangerous?
There are reports of any unforeseen situations with tourists in Antarctica, but rarely. For example, in November 2009, the Russian ship Kapitan Khlebnikov got stuck in the ice off the coast of the Antarctic Peninsula. Among its passengers were tourists and a film crew from the UK. The reason for the stop was the weather, but as soon as the tide began, the ship managed to free itself from the "white captivity". A Russian icebreaker with English tourists and television crews on board made a cruise in the region (West Antarctica).
A map of the mainland and the Antarctic Peninsula gives an idea of the location of the sea, but only experienced pilots can navigate ships between icebergs. In December 2013, drifting ice stopped the Russian ship Akademik Shokalsky. Passengers were evacuated aboard the Australian icebreaker in early January 2014.
Tour to Antarctica - a high portion of adrenaline is provided
According to the researchers of Antarctica, the mainland is suitable for organizing cruises, dog sledding and other outdoor activities. The history of sea cruises in Antarctica has more than 90 years. In 1920, enterprising ship owners began to take on board the first tourists who wanted to see the white continent with their own eyes. The cost of modern cruises and other types of travel to the shores of Antarctica and the South Pole ranges from 5,000 to 40,000 dollars. The price of the tour depends on many factors, not the last role is played by the complexity of the route, excursion support.
