Influence of climate-forming factors. Weather and climate
Weather is the state of the atmosphere over a specific area at a given time. The long-term weather regime within a specific territory is called climate. Since one year differs from another in the nature of the weather, only those climate indicators, which are derived over a long (at least 50) series of years.
Main climate-forming factors:
1) Geographic latitude: determines the average height of the Sun above the horizon. The largest amount of solar radiation on the Earth's surface arrives at the equator and decreases towards the poles.
2) Distribution of land and sea: the water surface and the land heat up and cool unequally (at one point in time the land will be hotter in summer and colder in winter than the ocean located at the same latitudes).
3) Distance from the ocean inland: affects the regime of temperature, humidity, determines the degree of continentality of a given climate.
4) Currents: warm currents in the seas and oceans contribute to increased temperatures in coastal land areas and increased precipitation; cold - lower the temperature on the outskirts of the continents and prevent precipitation. Thus, the climate of the eastern and western coasts South America, Australia and Africa, located within the same tropical climate, is different.
5) Relief: The climate is influenced by the direction of mountain ranges, which serve as an obstacle to wind and intrusion of air masses. Plains, on the contrary, allow continental or oceanic air masses to easily penetrate into neighboring areas.
6) Height above sea level: On average, the temperature decreases with height by 0.6°C/100 m, and therefore the higher the area above the horizon, the colder the climate there will be.
7) The nature of the underlying surface, which refers to the components of the earth's surface that interact with the atmosphere. A forest, for example, reduces the daily temperature range of the soil and, therefore, the surrounding air. Snow reduces heat loss from the soil, but it reflects a significant amount of sunlight, and the Earth therefore heats up little.
8) Human activity: In cities the air temperature is higher than in the surrounding areas. Air dust contributes to the formation of fogs and clouds, which leads to a reduction in the duration sunshine and precipitation. Human economic activity sometimes has an irreversible detrimental effect on the climate.
The Earth's climate is formed by four types of air masses: equatorial, tropical, temperate, arctic (Antarctic), which distribute their action across latitudinal zones. According to the dominant air mass in climate formation, the earth's surface is divided into climatic zones. Highlight basic climatic zones in which the same air mass operates throughout the year. There are seven such belts: one is equatorial, two each are tropical, temperate, as well as Arctic (in the northern) and Antarctic (in the southern hemisphere).
Belts in which alternation of adjacent types of air masses occur throughout the year are called transitional climatic zones. They are affected by an air mass coming from the equator in summer, and from the pole in winter.
Thus, 13 climatic zones are distinguished on the earth's surface. In each zone, under the influence of land and sea, continental and marine subtypes of air masses and climates are formed (Figure 3).
Equatorial belt(5° S - 10° N) - characteristic of the inner Amazon, the Congo Basin and the coast of the Gulf of Guinea, the Malacca Peninsula, the Sunda Islands and the island of New Guinea.
Throughout the year, the climate is formed by equatorial air masses. The belt is characterized by high temperatures ( all year round+24°C and +28°C) with a slight annual, more noticeable daily amplitude; upward movement air, a large amount of precipitation (from 1000 to 3000 mm), evenly distributed throughout the year. Powerful cumulus and cumulonimbus clouds are formed due to the fact that warm air rises, cools, and precipitation falls in the form of showers almost every day.
Air humidity in an equatorial climate ranges from 81 to 85%. There are no seasons. The length of the day throughout the year is equal to the night.
Subequatorial climate(up to about 20° N and S latitude) two seasons are characteristic: in summer equatorial air dominates and is very humid, and in winter tropical air dominates and is very dry. The average air temperature in all months ranges from +25 to +30°C. Hot summer, average temperature air above 30°C, the hottest month usually precedes the onset of the summer monsoon. Winter is noticeable cooler than summer, the temperature difference increases with distance from the equator.
The annual precipitation on the plains is 1000–2000 mm, on the mountain slopes it reaches 6000–10,000 mm. Almost all precipitation falls in summer. Winter monsoons bring precipitation, but only to the windward slopes of the mountains facing them. The plains are dry in winter. Duration of the dry period in sub equatorial belt ranges from one month on the border with equatorial climate to 11 months on the border with tropical deserts. Humidity in subequatorial climate is 70 and 87%.
Tropical zones(20 and 30° N and S on both sides of the tropics). Tropical air dominates here all year round, so the climate in central regions continents are hot and dry. The prevailing winds are trade winds. 70% or more of radiation heat is spent on heating desert sands and then, due to the high albedo of sands and cloudless skies, is unproductively radiated beyond the Earth.
The average July temperature reaches +40°C in the Northern Hemisphere and +35°C in the Southern Hemisphere. Absolute Highs air temperatures here are the highest on Earth: +57 – +58°С in inland areas North America (Death Valley) and in the Sahara, +55°C in Australia. Seasonal fluctuations in air temperature are much greater than in the equatorial zone. In winter, the temperature drops to +10 – +15°C. Throughout the Sahara in winter, light frosts with snowfall are possible when cold air invades from the north. The daily temperature fluctuations are especially large: up to 40° in the air and 80° on the soil. The nights are cold even in summer due to strong cooling in clear skies.
The cloud cover is insignificant, there is very little precipitation - less than 250 mm per year, and often even less than 100 mm. They fall very rarely, in some places in Arabia and the Sahara only once every few years, but in the form of showers. Their numbers increase in the eastern parts of the continents, which are influenced by trade winds blowing from the ocean and warm currents. In the west and in the center of the continents the climate is dry and desert. Therefore, there are two tropical climate regions: desert(typical of central continental regions) and humid .
Climate of the western edges of the continents (marine variety desert climate) is caused by cold currents, reverse stratification of air and trade wind circulation, carrying water vapor from the continent to the ocean.
IN eastern regions continents tropical zones, the climate is humid tropical. Marine air masses from the trade winds enter here, and a significant amount of precipitation falls.
Subtropical zones(30 – 40° N and S) – characteristic change climate regime by season: in summer tropical air with high atmospheric pressure dominates and the weather is dry, and in winter moderate air with low pressure and Central European weather spreads to these latitudes. In summer the temperature is 25-30°C, in winter up to 15°C.
The greatest longitudinal extent of the continents begins in the subtropical zone of the northern hemisphere; it causes longitudinal differentiation of the climate zone. Climatic regions are distinguished in the subtropical zone.
The western parts of the continents are characterized by a climate called Mediterranean, summers are dry and hot (+20 – +25°С), and winters are humid and warm (+5 – +10°С), but frosts are possible. Snow falls very rarely. Annual precipitation amounts are usually 400-600 mm, which creates semi-arid conditions.
On the eastern coasts of the continents the climate subtropical monsoon with roast (+25°C) rainy summer and cool dry winters. In many places the rainfall is more than 800 mm.
In the central parts of the continents the climate subtropical continental. Summer is very hot average monthly temperatures reach +30°C or more. In winter, the weather is unstable due to cyclones. Frosts down to -20°C are possible, rain or snow may fall, but the snow cover is unstable and melts quickly. The annual precipitation is about 600 mm, but in some areas it falls only 120 mm or even less.
Temperate zones ( from 40 to 60° N. and Yu. sh.). The main thing in atmospheric circulation is the westerly transport of air masses (in the Southern Hemisphere the famous “roaring forties” latitudes are famous for them), cyclonic and anticyclonic activity and the intrusion of both arctic and tropical air into the middle latitudes. Thus, not only moderate air masses dominate here throughout the year.
Temperate climates are characterized by high annual amplitude air temperature, which increases as you move deeper into the continents, increasing the continentality of the climate.
Over the larger area of the temperate zone, 500-400 mm of precipitation falls, and its territorial distribution is characterized by a consistent decrease inland. In the interior regions, which make up most of the belt, snow falls and a stable snow cover is formed that lasts up to six months.
IN temperate zone autumn and spring are long and well defined. In the west of the continents, westerly winds predominate, in the east - monsoons. There are great differences between Western, domestic and eastern parts continents.
On western coasts continents widespread nautical climate of temperate latitudes with warm (from +1°C in the north to +5°C in the south) and wet winters, cool (+15°C in the Northern Hemisphere and about +10°C in the Southern Hemisphere) and cloudy summers. Precipitation on the plain is 500-600 mm, on the windward side of the mountains the amount increases to 2000-2500 mm.
On the eastern coasts - monsoon climate with cold winter and cool rainy summers. In winter, a cold northwest wind blows from the continent, with temperatures of -20°C. In summer, southern and southeastern winds bring warm rainy weather. Closer to the ocean, where winds blow from the sea, precipitation falls in both winter and summer (from 1000 to 2000 mm per year). In winter, a thick snow cover forms.
In the interior areas - continental climate. Cyclones penetrate here less frequently than in coastal areas; pressure in winter is increased due to the cold anticyclone. Summers are warm, winters are cold with stable snow cover. Annual fluctuations in air temperature are large and increase as we move deeper into the continents. Most continental climate in northeast Eurasia, in Yakutia, where average January temperatures drop to -40°C. Precipitation within continents is decreasing.
Subarctic and subantarctic belt (between 60 - 70° N and S) - Arctic (Antarctic) air dominates in winter, and air masses of temperate latitudes in summer . There are no big differences between Western, Eastern and internal parts continents.
Winter is long, with average temperatures down to -40°C. Summer is short and cold, with an average temperature no higher than +10°C, but it can drop below 0°C. In the basins of the Java, Indigirka, Kolyma rivers northeast Yakutia, in the intermountain basins near the Verkhoyansk ridge and the Chersky ridge, there is a pole of cold Northern Hemisphere. The average monthly temperature in January is -50°C, absolute minimum up to -70°C.
Precipitation in western parts continents receives about 300 mm, and in the northeast of Yakutia - only 100 mm. The air is damp, heavily cloudy. Despite a small amount of precipitation, the moisture does not have time to evaporate completely. Therefore, small lakes are scattered throughout the tundra.
Arctic and Antarctic belt (from 70° N and S to the poles). Here the sun does not appear above the horizon for several months (polar night) and does not go below the horizon for several months (polar day). The snow surface has a high albedo and has a cooling effect on the troposphere. Throughout the year there is high pressure and easterly winds. The air in permanently frost climates is usually warmer than the underlying snow surface. In Antarctica, for example, the air temperature near the snow drops to -90°C.
In summer, the average air temperature in the Arctic is about 0°C, and on the coasts it reaches 5°C. In January, in the central Arctic it is -40°C, on the coast of the mainland -30°C, and on the Atlantic islands the temperature rises to -16°C (Spitsbergen). And only over Greenland does a stable anticyclone reduce the temperature in July to -14°C, and in January to -49°C. Fogs are very frequent. Precipitation in the European sector is 300-350 mm, in the Asian and American sectors - 160-250 mm (mainly in the form of snow). Long drizzle is typical for summer.
The climate of Antarctica is the coldest on Earth. In 1983, -89.2°C was recorded - this is the pole of cold. The average temperature in summer (January) is about -30°C, and in winter (August) – about -70°C. Cold air slowly spreads from the shield. However, on its outskirts the wind accelerates and hits the shores with powerful “katabatic” winds at speeds of up to 50 m/s. Average monthly summer air temperatures on the shores of Antarctica range from -1°C to -5°C, winter temperatures from -18°C to -20°C. Frequent storms occur when cyclones invade from the adjacent ocean, where they form over the boundary clean water and ice. In Central Antarctica the most dry place on Earth there is no precipitation.
The main features of the Russian climate are determined by a number of geographical factors. The most important of them is solar radiation, which depends on geographic latitude. In general, Russia is located predominantly in high and middle latitudes. Therefore, our climate in most of the country is harsh, with a clear change of seasons and a long winter. The significant extent of the country from north to south leads to climate change depending on the latitude of the place where solar heat is received - total solar radiation. In the Arctic total solar radiation is 251.2 kJ/cm 2 per year, in the subarctic - about 293 kJ/cm 2 per year. In the temperate zone, due to its large extent from north to south, the total solar radiation varies from 293 kJ/cm2 per year in the northern part to 544 kJ/cm2 per year in the southern part. In the subtropics, the amount of total solar radiation increases from 544 to 670 kJ/cm2 per year. Throughout Russia there is a very large difference in the seasonal supply of solar heat. This depends both on the change in the angle of incidence of the sun's rays over the seasons, and on the duration of sunshine. The seasonality of all natural phenomena is associated with differences in the supply of solar heat. The influence of the oceans on the climate of Russia The oceans have a huge influence on Russia's climate. The role of the Atlantic Ocean is greatest, despite the fact that its waters do not directly wash the territory of the country anywhere. IN temperate latitudes, in which most of our country is located, as is known, the western transport of air masses dominates. Moreover, in the west of Russia there is no high mountains, preventing air transfer. As a result, the influence of the Atlantic extends very far, right up to the Verkhoyansk and Transbaikal ranges. Marine air masses of temperate latitudes spread with western transport. In winter, they cause a softening of frosts up to thaws in the western regions, and bring snowfalls. In summer, the arrival of Atlantic masses is accompanied by cooling and precipitation. The climate-forming influence of the Arctic Ocean is very great. There is an area of high atmospheric pressure over the Arctic cold pool throughout the year. From here, the Arctic air, gradually transforming, spreads over the entire territory of Russia in the summer. Incline largest plains countries to the north contributes to the penetration of Arctic air far to the south. The impact of Arctic air is especially pronounced in the Eastern European plain . In winter, arctic air causes a sharp cooling here. Moving south, it becomes relatively warmer and dries out. Frosty ones are installed sunny days no snowfall. In summer, arctic air initially causes cooling, and then it warms up and forms cloudless or partly cloudy weather. The arrival of Arctic air on the territory of the European part of Russia is accompanied by a return of cold weather and is dangerous for many cultivated plants, as it causes frost. Most often they happen in May. Droughts in the Volga region and in the south are associated with the invasion of Arctic air Western Siberia. The Pacific Ocean has some influence on the climate of Russia. Despite huge size , its impact is limited to a relatively narrow strip of land along Far Eastern seas . This is due to the fact that the ocean is located to the east of our country, over which the westerly transport of air masses dominates in temperate latitudes. High mountains along the coasts also prevent Pacific air masses from penetrating into the interior of the country. Winter over cold surface On the continent, an area of high atmospheric pressure (Asian maximum) is formed, from where air rushes towards the relatively heated ocean (winter monsoon). Influence of air masses Pacific Ocean clearly affects only in summer. At this time, the area above the ocean high pressure , and over land the pressure is low. The result is the movement of sea air masses onto land in the form of the summer monsoon. Climate-forming factors include the nature of the underlying surface. In the conditions of our country, these are primarily the features of the relief. In winter, other differences in the nature of the underlying surface are leveled out by snow cover. The relief influences the climate throughout the year. The influence of relief on the climate of Russia It is winter in most parts of our country. In temperate and high latitudes, the radiation balance is negative at this time of year. Only in the extreme south does it have a positive meaning. The earth's surface becomes very cold in winter and cools the lower layers of air. This process is especially intense over the regions Eastern Siberia , remote from the oceans. In the northeast of Siberia, in intermountain basins, average January temperatures drop below -40°C, in the Oymyakon region to -48 -50°C. An area of high pressure is formed here, which spreads throughout Siberia and gives rise to two spurs. One spur grows to the northeast to Chukotka, and the second to the southwest through the south of Western Siberia and the Volga Upland to the lower reaches of the Dniester. In the interior regions of Siberia, within the area of high pressure in winter, downward air currents dominate. Therefore, windless, partly cloudy, frosty weather sets in. Calm air and very dry air make it easier to endure frosts and adapt to them. In winter, air pressure over Russia is increased, and over the surrounding seas and oceans it is reduced. Therefore, the spreading of air from the territory of the country towards the oceans prevails, with the exception of the European part of the country. On the coasts of the Pacific seas in winter, northern westerly winds (winter monsoon), which carry cold, dry air from continental Siberia. In this regard, in almost all regions of the Far East, winter is light and cold. In Vladivostok, which is located at the latitude of Sochi, the average January temperature is -12°C, and in Sochi +6°C. Over the coasts of Kamchatka and Sakhalin Island, where continental and maritime air masses collide, frontal processes arise, which are often accompanied by heavy winds and heavy snowfalls. and the south of the European part of the country, northeast winds dominate. They are caused by the outflow of air masses to the south from the spur of the high pressure area. As the air moves from the northeast, it brings cooling and relative dryness to the southern regions of the country, so little snow falls here, and in severe winters the Sea of Azov and the northern parts of the Caspian and Black Seas freeze. In the central and northern parts of the East European Plain, north of the high pressure spur, westerly air flows from the Atlantic Ocean dominate. These air masses always bring moisture in the form of snow or rain. But their temperatures are different. If southwesterly winds bring thaws in winter, then the northwestern ones bring relatively cold air from the North Atlantic and Scandinavia. A large number of cyclones move over much of the European Plain during the winter. They arise along the polar front, which passes to the west of our country over the North Sea. From here, cyclones move east, passing over Western and Eastern Europe. Space and ground monitoring of their movement makes it possible to predict the weather in the European part of the country.. For example, in Moscow in January 1988 and 1990. temperatures rose to +4°C, and in 1940 they dropped to -42°C. Warm Atlantic air masses, moving east, gradually cool down. Therefore, isotherms over the European territory of Russia have meridional direction . Over Eastern Siberia, the isotherms have a closed ring-shaped character, reflecting the continental climate of this territory. The Pacific Ocean has less of a warming effect on the continent compared to the Atlantic. Therefore, on the Pacific coast, isotherms are located meridionally only within a narrow strip. Over the southern regions of the country, isotherms extend latitudinally in accordance with the direction of change in the value of total solar radiation and the radiation balance. Precipitation and pressure In most of Russia, precipitation falls in the form of snow in winter. In the North Caucasus, the thickness of the snow cover usually does not exceed 10 cm; V Kaliningrad region , in the Volga region - up to 10-30 cm. In the north of the European Plain, north-east of Western Siberia, on Sakhalin - 80-90 cm, and on east coast In Kamchatka, the thickness of the snow cover reaches 120-160 cm. The duration of snow cover is also very different - from several days in a number of regions of the Caspian region to 260 days in Taimyr. Snow has great importance For natural processes and economic activities on the territory of our country. It creates moisture reserves that are used by plants in spring and early summer. Thanks to snow, it is possible to grow winter crops in the European part of the country. In spring, most rivers experience floods caused by melting snow. In summer, throughout Russia, the radiation balance is positive. The continent warms up more than the oceans, and an area settles over it low blood pressure. At the same time, areas of high pressure are growing over the oceans: the North Atlantic (Azores) and North Pacific (Hawaiian) highs. High blood pressure continues to exist over the Arctic Ocean (Arctic Maximum). From these highs air currents rush to the continent. The flow of sea air is most clearly expressed in Far East, where in the summer a southeastern air movement is established - the summer monsoon. It's colder and therefore heavier here. sea air(monsoon rains) on Sakhalin, Kamchatka, Khabarovsk and Primorsky territories. Quite often, powerful cyclones come here in the form of typhoons that arise on tropical fronts outside our country. Monsoon rains are accompanied by flooding of rivers. Floods are often catastrophic, especially in the Amur and Ussuri river basins on Sakhalin Island. In northern Russia, Arctic air masses rush south toward warmer land. Over the northern seas they meet the air of temperate latitudes. As a result, an Arctic front is formed. It is especially well expressed over the Barents Sea, since the most contrasting air masses interact over this relatively warm basin. The passage of the Arctic front over the northern seas is accompanied by storms and fog. Air from the north moves far south over the plains of Western Siberia. To the south of Central Asia, over the territory of Pakistan and Afghanistan, there is a center of low pressure (South Asian Low), towards which northern air currents rush. Moving south, the Arctic air warms up, dries out and gradually transforms into continental air of temperate latitudes. Over the plains of Central Asia it is very dry and forms a desert climate. To the west of Russia, the Azores Maximum grows over the Atlantic Ocean in summer, a spur of which passes over the East European Plain through and cold snaps. Thus, the average monthly July temperature in Moscow is about +18°C, but in some years it dropped to +5...+10°C or rose to +30...+34°C. To the east of the Volga, and especially beyond the Urals, the influence of sea air masses decreases sharply, and here in summer the weather is usually dry and hot. Unlike the winter season, summer isotherms stretch from west to east throughout almost the entire territory of Russia. This is due to the fact that in summer solar radiation is very high and it plays a major role in determining the temperature regime. The summer season is maximum amount precipitation. This is due to high temperatures and therefore maximum humidity local air from which precipitation falls when it interacts with relatively cold air masses coming from the oceans. Precipitation of convective origin is added to them. Largest quantity precipitation falls in the extreme western and eastern regions of Russia. With distance from the oceans to the interior of the country, the amount of precipitation decreases, reaching its minimum (less than 50 mm). On the windward slopes of the mountains, the amount of precipitation increases significantly. Especially a lot of them fall on western slopes Caucasus Mountains(over 2000 mm). Climatic conditions in the country Climatic conditions vary significantly across Russia. From north to south, our country is located in the Arctic, subarctic and temperate climate zones. Significant climate changes are observed within each zone, both from west to east (climatic regions) and from north to south (zonal climate types). Since climatic differences are reflected primarily in the nature vegetation cover, the names of zonal climate types within climatic regions are given according to the dominant vegetation cover. The Arctic zone is dominated by the climate of Arctic deserts. Cold arctic air masses are typical here throughout the year. During polar night The flow of solar radiation stops, and temperatures drop to -40...-50°C. During the polar day, air temperatures rise to 0...+4°C. Dominates all year round cloudy weather . Precipitation falls mainly in the form of snow. Most of sushi on Franz Josef Land, Tundra and forest-tundra climate types are distinguished. In the tundra type of climate in summer the temperature is +4...+11°C. Due to the proximity of the Arctic front, cloudy weather prevails all year round, and there are often strong winds. There is little precipitation (200-300 mm per year), but due to low evaporation there is excessive moisture in the area. In the forest-tundra climate type, summer temperatures are +11...+14°C. The annual amount of precipitation also increases to 400 mm. The temperate climate zone has several climate types. The largest area is occupied by territories with a taiga climate, with cold winters and cool summer . The average temperature in July is +15...+20°C. Moderate amount precipitation (300-600 mm per year). Precipitation prevails over evaporation. The snow cover lasts all winter. The climate of mixed forests is represented mainly on the East European Plain, where penetrations of Atlantic sea air are frequent. Summers are warm and winters are mild with frequent thaws. The annual precipitation is greater than in the taiga and amounts to 600-700 mm per year. The monsoon climate of the mixed forests of the Far East covers Amur region and Primorsky Krai. As well as in mixed forests European plain, in its formation the leading role belongs to the sea air of temperate latitudes. But sea air comes from the Pacific Ocean only in summer. In winter, cold, strong winds blow from the mainland. In the second half of summer there are heavy monsoon rains. In the forest-steppe type of climate, average July temperatures rise to +19...+21°C. The amount of precipitation decreases and the moisture balance becomes negative. This type of climate is characterized by unstable moisture - dry years are replaced by wet ones, droughts and hot winds are frequent. In steppe climates, summer temperatures increase. Average July temperatures reach +21...+23°С. The annual precipitation decreases to 300 mm. Evaporation exceeds the amount of precipitation by 2-3 times. air is accompanied by sharp daily fluctuations in soil and air temperatures. All these territories differ from other areas of our country in the abundance of solar heat and light. This makes it possible to grow a number of valuable agricultural crops here, and primarily cotton on irrigated lands. Small spaces Black Sea coast The Caucasus (the territory of the Krasnodar Territory, the regions of Anapa, Novorossiysk, Tuapse, Sochi, Adler) belongs to the subtropical zone, to the climate of the humid Mediterranean subtropics. The January temperature varies from +2°С (Anapa) to +6°С (Sochi). North of Tuapse, the annual precipitation is 1200 mm, but quickly decreases to 800 - 900 mm in the Gelendzhik region and to 400 mm in the Anapa - Novorossiysk region. In the western part of the Adler district and in the south of the Lazarevsky district of the Krasnodar Territory, on the slopes facing the sea (up to a height of 600 m), the amount of precipitation reaches 2000 - 2400 mm. Summers are warm but humid, winters are also warm and humid. The average temperature in June - July rises to +23...+24°С and such values do not change during August - September. The average minimum air temperature in the low foothill zone (up to an altitude of 1000m) is everywhere above +15°C. A stable snow cover is formed only from a height of the Black Sea coast, 600 - 800 m, the duration of which increases with height and reaches maximum values of 50 - 70 cm at the level of 1100 - 1300 m. On the coast, wet snow falls, which lasts from several hours to 1 - 2 days. Wet snow causes great destruction. Under the weight of snow and(“Novorossiysk Bora”) trees are broken, communication and power lines are torn. This phenomenon was observed in the Sochi region in 1911 (from February 3 to 5), when the fallen snow formed a cover 80 cm high, and on December 18 - 20, 1997. Wind speed reaches 42 - 47 m/s even at low air temperatures. On December 18 - 20, 1997, the temperature dropped to -21°C, which led to enormous destruction of industrial facilities, populated areas and was accompanied by casualties. Climate has a great influence on many important sectors of economic activity and human life. It is especially important to take into account the climatic characteristics of the territory when organizing agricultural production. Agricultural crops can produce high, sustainable yields only if they are placed in accordance with the climatic conditions of the area. Thus, growing cotton requires a long growing season, large amounts of solar heat and moisture. But moisture should not come in the form of rain and snow. Therefore, irrigation is necessary to grow cotton. In areas where there is a lot of heat and a lot of rain, cotton cannot be grown. In these areas, valuable subtropical crops such as lemons, tangerines, and tea are grown. Winter wheat can be sown only where the snow cover is stable during the winter and its thickness is at least 20-30 cm. In steppe and forest-steppe climate You can get good yields of corn, sugar beets and sunflowers. In the humid north, where the supply of solar heat is limited, rye, oats, potatoes, onions, and cabbage are grown. All types of modern transport in very to a large extent depend on climatic conditions. Storms, hurricanes and fogs, drifting ice make navigation difficult. Thunderstorms and fogs make it difficult and sometimes become an insurmountable obstacle for aviation. Therefore, the safety of maritime and airships largely provided by weather forecasts. For smooth movement railway trains In winter we have to deal with snow drifts. For this along all rainwater. In dry areas North Caucasus roofs are flat because they help retain and utilize moisture from the occasional rainfall. Duration depends on climatic conditions heating season and methods of heating homes, public and industrial buildings. Areas with the most favorable climate for human life and health are used as healing areas - resorts. These are the resorts of the Caucasian coasts of the Black and Caspian seas, the Kaliningrad region, many mountainous areas and even deserts, where climate is used as the main therapeutic agent (climatotherapy). Climate and weather processes increasingly have to be taken into account when organizing protection atmospheric air from pollution. To combat air pollution in factories and factories, they build wastewater treatment plants. In vehicles, special devices are used - catalysts, which reduce exhaust gas emissions into the atmosphere. But all these methods do not yet completely prevent air pollution. Therefore, it is necessary to take into account the influence of atmospheric processes on the degree of air pollution. When locating residential areas and industrial enterprises, prevailing wind directions should be taken into account. Industrial enterprises should be located on the leeward side to prevent their emissions from entering the city.Anticyclones are dominated by downward air currents, which lead to the accumulation of pollutants in the surface layers of air. Obviously, under anticyclonic weather conditions, enterprises and transport must sharply reduce emissions of pollutants into the atmosphere. In areas of the country where anticyclonic weather conditions prevail, all industrial and transport emissions should be minimal. For this reason, atmospheric pollution is especially dangerous in the intermountain basins of Eastern Siberia. But observations show that, despite the measures taken, the problem of air pollution in the country remains very acute. For example, emissions of harmful substances into the atmosphere
industrial enterprises in the first half of 1989 amounted to 29 million tons. That is why the fight against “dirty” production is becoming increasingly widespread Our country, its location in several climatic zones lead to the fact that in different parts of the country the temperatures of January and July and the annual amount of precipitation differ greatly.
Thus, average January temperatures range from O °C in the Ciscaucasia to -40-50 °C in Yakutia. July temperatures vary from -1 °C on the northern coast of Siberia to + 24-25 °C in the Caspian lowland.
Let's analyze the maps of average isotherms in January and July in Russia. Pay attention to how they pass. January isotherms extend from northwest to southeast. The location of the July isotherms, on the contrary, is close to the latitudinal one.
How can we explain this picture? It is known that the temperature distribution depends on the amount of solar radiation, the underlying surface, and atmospheric circulation. Intensive cooling of the surface of our country in winter period leads to the fact that the lowest temperatures are observed in inland areas inaccessible to the warming influence of the Atlantic, and in areas of Central and North-Eastern Siberia. Average monthly temperatures in July are positive throughout Russia.
Precipitation distribution on the territory of our country is associated with the circulation of air masses, features relief as well as air temperature. The main source of moisture for our country is the humid air of the Atlantic. The greatest amount of precipitation on the plains falls between 55° and 65°N. w. Precipitation is distributed extremely unevenly throughout our country. The decisive factors in this case are proximity or distance from the sea, the absolute height of the place, the location of mountain ranges (retaining moist air masses or not preventing their movement)
The greatest amount of precipitation in Russia falls in the Caucasus and Altai mountains (more than 2000 mm per year), in the south of the Far East (up to 1000 mm), as well as in the forest zone of the East European Plain (up to 700 mm). The minimum amount of precipitation occurs in the semi-desert areas of the Caspian lowland (about 150 mm per year).
But the annual precipitation does not give a complete picture of how the territory is provided with moisture, since some atmospheric precipitation evaporates, some seeps into the soil.
To characterize the provision of moisture to a territory, the humidification coefficient (K) is used, showing the ratio of the annual amount of precipitation (O) to evaporation (I) for the same period: K = O/I.
Volatility is the amount of moisture that can evaporate from a surface under given atmospheric conditions.
The evaporation rate is measured in mm of the water layer. Volatility characterizes possible evaporation. Actual evaporation cannot exceed the annual amount of precipitation falling in this place. For example, in the Caspian deserts, evaporation is 300 mm per year, although evaporation here, in hot summer conditions, is 3-4 times higher.
The lower the humidification coefficient, the drier the climate. When K = 1, moisture is considered sufficient. Sufficient hydration is characteristic of southern border forest and northern, borders of the forest-steppe zone. In the steppe zone, where the moisture coefficient less than one(0.6-0.7), moisture is considered insufficient. In the Caspian region, in the zone of semi-deserts and deserts, where K = 0.3, moisture is poor. But in some areas of the country K> 1, i.e. the amount of precipitation exceeds evaporation. This type of hydration is called excess hydration.
Excessive moisture is typical for taiga, tundra, and forest-tundra. There are many rivers, lakes, and swamps in these areas. Here, water erosion plays a significant role in the processes of relief formation. In areas with insufficient moisture, rivers and lakes are shallow, often dry out in summer, vegetation is sparse, and wind erosion predominates in relief formation.
The climate features of Russia are determined by a number of geographical factors: geographical location, the size and extent of the territory from west to east and from north to south, atmospheric circulation, distance from the oceans, a wide variety of terrain, etc.
The northern part of the country extends far beyond the Arctic Circle. The situation is predominantly in high and middle latitudes, which means that in most of the territory the climate is harsh, with a clear change of seasons and long winters. The severity of the climate is also facilitated by the “openness” of Russian territory over a large area to the seas of the Arctic Ocean.
The significant extent of the country from north to south leads to a change in the total solar radiation received. The southern regions of our country receive the maximum amount of it; the highest air temperatures are recorded here. There is also a big difference in the seasonal supply of solar heat. In winter, there is snow almost everywhere in Russia.
The oceans have a huge influence on the climate. The role of the Atlantic Ocean in weather formation is great (westerly transport of winds dominates). In the west of Russia there are no high mountains that prevent the passage of air masses from the Atlantic, and they extend all the way to the Verkhoyansk and Transbaikal ranges (the low Ural Mountains are not an obstacle).
The decreasing influence of Atlantic air masses on the climate is manifested in an increase in the degree of continentality from west to east. At the same time, the amount of precipitation decreases, and the amplitudes of temperature fluctuations increase (the difference between the average temperatures of day and night, summer and winter months).
The climate-forming influence of the Arctic Ocean is very great. There is an area of high atmospheric pressure over the Arctic cold pool throughout the year. From here, the cold air, gradually transforming (heating up and drying out), spreads over the entire territory of Russia.
The Pacific Ocean has some influence, but its influence is limited to a relatively narrow strip of land along the Far Eastern seas (the summer monsoon brings heavy rains).
Climatic differences on the territory of Russia are manifested in the formation different types climate. In the direction from north to south, our country is located in the Arctic, subarctic and temperate climatic zones. But significant climate changes are also observed within each zone: both when moving from west to east (climatic regions), and when moving from north to south (zonal climate types). For example, there are four climatic regions of the temperate climate zone: moderate continental, continental, sharply continental and monsoon (in the Far East).
Climate has a great influence on the formation of many of the most important sectors of economic activity and the living conditions of people (for example, most of the territory of Siberia and the Far East is not inhabited or developed due to natural and climatic conditions).
And factors influencing climate. The main factors are the factors that determine the climate at any point globe. These include: solar radiation, and.
In the mountains, climatic conditions change with changes in altitude: as it increases, it decreases, pressure drops, humidity decreases, increases to a certain height, and then decreases, changes in speed and direction in a complex manner, and other climate indicators also change. All this makes it possible to identify altitudes specific to mountains.
The influence of land and surface surfaces is reflected in the fact that they practically do not distort the direct influence of the first two climate-forming factors, receiving the amount of heat corresponding to the latitude and without distorting the direction and speed of movement of air masses.
In addition to the main ones, there are factors that have a significant impact on the climate in certain (often vast) areas. In particular, the distribution of land and sea and the remoteness of the territory from the seas and oceans. Land and sea heat and cool differently. Marine air masses differ significantly from continental ones, but as they move deeper into the continents, they change their properties. Therefore, at the same latitude there are significant differences in temperature and precipitation distribution. So, at parallel 60° N. average temperature in January
The role of climate in human economic activity cannot be overestimated. Climate influences the ratio of heat and moisture, influences the conditions for the occurrence of modern relief-forming processes, participates in the formation of internal waters, and in the development and distribution of flora and fauna. Throughout life and activity, a person has to take into account his characteristics. The founders of climatology A.I. made a huge contribution to the study of Russian climate. Voeikov, A.A. Kaminsky, P.I. Brounov, B.P. Alisov, S.P. Khromov, M.I. Budyko et al.
Definition 1
Climate- This is a long-term weather regime characteristic of a particular area.
Climate related:
- With the amount of solar radiation that enters a particular territory;
- With the movement of air masses;
- With atmospheric fronts;
- With atmospheric circulation;
- With the underlying surface of the earth.
It has its own main indicators:
- Air temperature;
- Prevailing wind;
- Annual amount of precipitation and its regime.
Climatic indicators are plotted on a special thematic map called a climatic map.
Definition 2
Weather is the state of the atmosphere in a given place and at a given time.
The main characteristics of weather are its elements and phenomena.
Weather elements include:
- Air temperature;
- Air humidity;
- Atmosphere pressure.
Weather phenomena are:
- Wind;
- Cloudiness;
- Precipitation.
Weather phenomena can be catastrophic in nature, which manifests itself in the form of hurricanes, showers, droughts, and thunderstorms.
The weather is also characterized totality elements and phenomena. For example, at the same temperature, but different humidity, the weather will be different. The weather may change during the day.
The main reasons for variability:
- The amount of solar heat received during the day;
- Movement of air masses;
- Atmospheric fronts;
- Action of cyclones and anticyclones.
The supply of solar heat in temperate latitudes is often disrupted by changes in air masses, the passage atmospheric vortices and fronts.
Climate formation factors
The climate of any territory is formed due to the influence of a number of factors, which are called climate-forming factors. Analysis of these factors reveals the genesis of climate and explains geographical distribution its elements.
Main climate-forming factors:
- Geographical location of the territory;
- Terrain;
- Features of the underlying surface;
- Radiation conditions;
- Atmospheric circulation;
- Air masses;
- Atmospheric fronts.
Geographical position territory determines the amount of solar radiation arriving on its surface. Russia's position in temperate latitudes explains the dramatic changes in the amount of solar heat between seasons. For example, the Franz Josef Land archipelago receives $60$ kcal/sq cm, and the extreme south of the country already receives $120$ kcal/sq cm. The proximity of the oceans also has a great influence on the climate of the territory. Oceans influence the distribution of clouds and the flow of more humid air to land. Russia in the north and east is washed by the waters of two oceans and the dominant western transport of air masses in temperate latitudes limits the influence of the seas within a narrow coastal strip. IN summer period large clouds in the Far East reduce solar radiation. In the area of the Sikhote-Alin ridge it is approximately equal to the total solar radiation in the north Kola Peninsula, Yamal and Taimyr.
The climate of Russia is significantly influenced by relief terrain. Most of Russia's territory is under the influence of the Atlantic and Arctic Ocean, which is ensured by its openness to the north and northwest. The mountains located along the southern and eastern outskirts of Russia limit the influence of the Pacific Ocean and Central Asia. A special mountain climate is formed in the mountains, which changes with altitude.
In addition to topography, climate is also influenced by other features. underlying surface. For example, the presence of snow cover changes the ratio of reflected and absorbed radiation due to the high albedo of snow. Freshly fallen snow reflects $80$-$95$% of radiation. Tundra, forests, dry steppes, and meadows have different reflectivity. Low reflectivity is typical for coniferous forest– $10$-$15$% total. Dark soil surfaces absorb heat three times more than dry, light sandy soils. This is associated with changes in the temperature of the soil surface and ground air layer.
Solar radiation- This is the main energy base for climate formation. The further from the equator, the less solar radiation reaches the surface. The incoming part of the radiation balance is the total radiation. Reflected radiation is a consumable part and depends on the albedo of the underlying surface. In general, radiation becomes more effective in the direction from north to south. The most northern islands Russia has a negative radiation balance. It reaches its maximum value in Western Ciscaucasia.
Along with radiation circulation processes on Russian territory are no less important. Land and ocean, due to their differences physical properties, are heated and cooled unequally, which leads to different atmospheric pressure and the movement of air masses - atmospheric circulation. There is a change in the prevailing winds, bringing different air masses. But, it must be said that in the territory of most of Russia, the western transport of air masses and the associated precipitation predominate throughout the year. Russia is characterized by three main types of air masses that determine the features of its climate.
Air masses:
- Arctic air mass;
- Air of temperate latitudes;
- Tropical air mass.
Economic climate assessment
Human life and his economic activity are closely connected with each other. Not all of the planet's land has favorable conditions for life, as the French geographer E. Reclus believed back in the 19th century. He wrote about this in his classic work “Man and the Earth.” Those areas where average annual temperature falls below -$2$ degrees, the scientist considered unsuitable for human life. Reclus was wrong, because in Russia there are areas where the average annual air temperature is lower than the value he indicated. Northeast Russia generally reaches record average annual temperatures of -$10$, -$16$ degrees. Man has learned to adapt to any unfavorable natural conditions, and in our time adaptation is helped by modern developed production, technology, and new methods of protection.
Of course, in order to provide normal living conditions for people in the harsh northern regions, additional material costs are required. The southern regions, where the climate is favorable for life, are used as recreational areas for health purposes, and climatic resorts are created there. Any human activity must take into account the climatic features of the area, be it any construction, transport, laying pipelines, building power plants, etc. Climate is the most important resource for the development of agricultural production, for which its agroclimatic assessment is very important. The development of such an assessment and agroclimatic zoning of Russia belongs to D.I. Shashko. Since Russia is northern country and the winter period is of great importance, then the severity of winter and the depth of snow cover were taken into account during agroclimatic zoning.
Definition 3
Agroclimatic resources – is the sum of active temperatures above +$10$ degrees, ensuring agricultural production.
Temperatures favorable for plant growth and soil moisture in the area fluctuate within a fairly wide range. Changing these indicators makes it possible to cultivate a variety of crops from fiber flax to tea, from sunflower, sugar beets to rice and soybeans. Economic and especially agricultural development of the territory must take into account unfavorable climatic phenomena.
These phenomena include:
- Droughts and hot winds;
- Hurricanes and dust storms;
- Frosts during the growing season;
- Severe winter frosts;
- Hail and ice;
- Fog and ice.
Note 1
Taking these climate features into account is important because most of Russia’s arable land is located in the risky farming zone.
The planet's climate is not constant, it changes over time. Sometimes the weather is the same season current year may vary greatly depending on the weather previous year. In addition, over the course of tens, and even more so hundreds and thousands of years, the climate situation changes significantly. This is influenced by various factors. They can be classified as follows:
- planetary - solar radiation, air masses, rotation of the Earth around its axis and the Sun, moisture circulation;
- geographical - latitude of the area, influence of ocean currents, nature of the relief and underlying surface;
- anthropogenic – the results of human activity, in particular pollution of the biosphere.
Among this number of climate-forming factors, scientists identify three main ones that influence climate change. These are relief, solar radiation and circulation of air masses. It is these parameters that influence the formation of the climate of a particular point on the planet.
Amount of solar radiation
The amount of solar radiation that reaches the surface of the earth determines the heat, temperature of the atmosphere and the upper layer of the lithosphere. IN different parts On the planet, heat is distributed unevenly, depending on geographic latitude. The closer to the equator, the hotter it is, and the colder it is towards the poles. The influx of solar radiation is influenced by climatic indicators such as atmospheric circulation, precipitation, cloudiness and pressure. The course of all life cycles of the planet depends on the radiation of the Sun.
Movement of air masses over earth's surface ensures climate change. They are continental and oceanic, depending on what part of the planet they formed over. During atmospheric circulation, clouds move, affecting the following weather indicators:
- precipitation;
- air humidity;
- temperature;
- wind direction and strength.
The main landforms are mountains and plains, which significantly influence the climate. Temperature conditions, pressure and wind speed in the mountains will differ sharply from those on the flat surface. At the same time, the weather conditions differ in the foothills, on ridges, and slopes. The tops of the mountains are covered with glaciers and snow. On various shapes relief hits different quantities solar radiation, and mountains prevent the movement of air masses.
Thus, the climate is influenced by various factors, among which the most important are solar radiation, topography and air masses. All these factors interact with each other and shape both the weather in a specific point on the globe and influence climate changes on the Earth as a whole.