– the state of the atmosphere in a given place on Earth at a certain moment or time interval. This state is determined by the dynamics of the atmosphere, physical and chemical processes in it and its interaction with the Earth’s surface and with outer space, as well as with processes determined by their own internal energy atmosphere and surface of the Earth. The totality of weather in a given place is called climate.
Climate.
In Greek, climate means slope. In climatology, we mean the inclination of the earth's surface towards the sun's rays. Climate is one of the main geographical characteristics of a particular area, it determines the long-term statistical weather regime of this place. The main features of the climate depend on the supply of energy from solar radiation, circulation air masses in the atmosphere and the nature of the underlying surface of a given place. In addition, the climate of a particular region is determined by the geographical latitude and altitude of the place above sea level, its distance from sea coasts, the characteristics of orography (relief) and vegetation cover, the presence of glaciers and snow covers, and the degree of atmospheric pollution. The Earth's rotation around its axis, inclined to the equatorial plane by 23.26°, and the Earth's revolution around the Sun lead to daily and annual weather variations, as well as to certain latitudinal (zonal) patterns of climate on Earth.
Sun, weather and climate.
The influx of sunlight and heat arriving at the rotating Earth leads to daily temperature changes at almost all latitudes, except for the polar ice caps, where nights and days can last up to six months. Daily and annual changes in the Earth's exposure to solar rays lead to complex periodic variability in heating in different regions of the Earth. The result of unequal heating in different areas land, ocean and atmosphere is the emergence of powerful jet currents in the oceans, as well as winds, cyclones and hurricanes in the troposphere. These movements of matter smooth out temperature changes, while they have a strong influence on the weather at every point on Earth and, thereby, shape the climate on the entire planet. It can be expected that the thermal regime on Earth, established over thousands of years, should provide a very accurate repeatability of weather phenomena in each given region. However, in many other places, while general patterns remain the same, noticeable deviations from the average are often observed over many years. All these anomalies, at least partially, may be associated with solar activity.
Against the backdrop of a relatively stable climate, the weather is constantly changing, mainly due to atmospheric circulation. The weather is most stable in tropical countries and most variable in mid-latitudes and circumpolar regions, in particular in the north of the Atlantic and Pacific oceans, where cyclones often arise and develop. Daily weather forecast methods are based on the construction of daily surface and high-altitude synoptic weather maps, to the analysis of which general physical laws are applied atmospheric processes. When forecasting for 3–5 days or more, various statistical techniques are used ( cm. METEOROLOGICAL PHENOMENA).
Main types of climate.
The climate classification provides an orderly system for characterizing climate types, their zoning and mapping. The types of climate that prevail over large areas are called macroclimates. A macroclimatic region must have more or less homogeneous climatic conditions that distinguish it from other regions, although they represent only a generalized characteristic (since there are no two places with an identical climate), more consistent with reality than the identification of climatic regions only on the basis of belonging to a certain latitude -geographical zone.
Ice sheet climates dominate Greenland and Antarctica, where average monthly temperatures are below 0° C. During the dark winter season, these regions receive absolutely no solar radiation, although there are twilights and auroras. Even in summer, the sun's rays hit the earth's surface at a slight angle, which reduces the efficiency of heating. Most of the incoming solar radiation is reflected by the ice. In both summer and winter, the higher elevations of the Antarctic Ice Sheet experience low temperatures. The climate of the interior of Antarctica is much colder than the climate of the Arctic, since the southern continent is different large sizes and altitudes, and the Arctic Ocean moderates the climate, despite the widespread distribution of pack ice. During short periods of warming in summer, drifting ice sometimes melts. Precipitation on ice sheets falls in the form of snow or small particles of freezing fog. Inland areas receive only 50–125 mm of rainfall annually, but the coast can receive more than 500 mm. Sometimes cyclones bring clouds and snow to these areas. Snowfalls are often accompanied by strong winds that carry significant masses of snow, blowing it off the rocks. Strong katabatic winds with snowstorms blow from the cold ice sheet, carrying snow to the coasts.
Subpolar climate occurs in tundra areas on the northern edges North America and Eurasia, as well as on the Antarctic Peninsula and adjacent islands. In eastern Canada and Siberia, the southern limit of this climate zone lies well south of the Arctic Circle due to the strong influence of vast land masses. This leads to long and extremely cold winters. Summers are short and cool with average monthly temperatures rarely exceeding +10° C. To some extent, long days compensate for the short duration of summer, but in most of the territory the heat received is not enough to completely thaw the soil. Permanently frozen ground, called permafrost, inhibits plant growth and the filtration of meltwater into the ground. Therefore, in summer, flat areas become swampy. On the coast, winter temperatures are slightly higher and summer temperatures are slightly lower than in the interior of the mainland. In summer, when humid air is above cold water or sea ice, fog often occurs on Arctic coasts.
The annual precipitation usually does not exceed 380 mm. Most of them fall in the form of rain or snow in the summer, during the passage of cyclones. On the coast, the bulk of precipitation can be brought by winter cyclones, but the low temperatures and clear weather of the cold season, characteristic of most areas with a subpolar climate, are unfavorable for significant snow accumulation.
The subarctic climate is also known as the “taiga climate” (based on the predominant type of vegetation - coniferous forests). This climate zone covers the temperate latitudes of the Northern Hemisphere - the northern regions of North America and Eurasia, located immediately south of the subpolar climate zone. Sharp seasonal climatic differences appear here due to the position of this climate zone at fairly high latitudes in the interior of the continents. Winters are long and extremely cold, and the further north you go, the shorter the days. Summer is short and cool with long days. In winter, the period with negative temperatures is very long, and in summer the temperature can at times exceed +32 ° C. In most of the climate zone under consideration, less than 500 mm of precipitation falls per year, and its amount is maximum on the windward coasts and minimum in the interior of Siberia. There is very little snowfall in winter; snowfalls are associated with rare cyclones. Summer is usually wetter, with rain occurring mainly during the passage of atmospheric fronts. The coasts are often foggy and overcast. In winter in very coldy Icy fogs hang over the snow cover.
A humid continental climate with short summers is characteristic of a vast strip of temperate latitudes in the Northern Hemisphere. In North America it extends from the prairies of south-central Canada to the Atlantic coast, and in Eurasia it covers most Eastern Europe and some areas of Central Siberia. The same type of climate is observed on the Japanese island of Hokkaido and in the south of the Far East. Basic climatic features These areas are determined by the predominant westerly transport and frequent passage of atmospheric fronts. During severe winters, average air temperatures can drop to –18° C. Summers are short and cool, with a frost-free period of less than 150 days. The annual temperature range is not as great as under conditions subarctic climate. In Moscow, the average January temperatures are –9° C, July – +18° C. In this climate zone, spring frosts pose a constant threat to agriculture. In the coastal provinces of Canada, New England and Hokkaido, winters are warmer than inland areas, as easterly winds at times bring warmer ocean air.
Annual precipitation ranges from less than 500 mm in the interior of continents to more than 1000 mm on the coasts. In most of the region, precipitation falls mainly in the summer, often with thunderstorms. Winter precipitation, mainly in the form of snow, is associated with the passage of fronts in cyclones. Blizzards often occur behind a cold front.
Humid continental climate with long summer. Air temperatures and the length of the summer season increase to the south in areas of humid continental climate. This type of climate occurs in the temperate latitude zone of North America from the eastern Great Plains to Atlantic coast, and in southeastern Europe- in the lower reaches of the Danube. Similar climatic conditions are found in northeastern China and central Japan. Western transport is also predominant here. Average temperature most warm month+22°C (but temperatures can exceed +38°C), summer nights are warm. Winters are not as cold as in areas of humid continental climates with short summers, but temperatures sometimes drop below 0 ° C. The annual temperature range is usually 28 ° C. Most often, in humid continental climates with long summers, precipitation falls from 500 to 1100 mm in year. Nai large quantity precipitation is brought by summer thunderstorms during the growing season. In winter, rains and snowfalls are mainly associated with the passage of cyclones and associated fronts.
Temperate maritime climate characteristic of the western coasts of continents, primarily northwestern Europe, the central part of the Pacific coast of North America, southern Chile, southeastern Australia and New Zealand. The course of air temperature is moderated by the prevailing westerly winds blowing from the oceans. Winters are mild with average temperatures in the coldest month above 0°C, but when arctic air flows reach the coasts, there are also frosts. Summers are generally quite warm; with intrusions of continental air during the day, the temperature can briefly rise to +38° C. This type of climate, with a small annual temperature range, is the most moderate among climates of temperate latitudes.
In areas of temperate maritime climate, the average annual precipitation ranges from 500 to 2500 mm. The windward slopes of the coastal mountains are the most humid. Cyclones moving from the oceans bring a lot of precipitation to the western continental margins. In winter, as a rule, it lasts cloudy weather with light rains and rare short-term snowfalls. Fogs are common on the coasts, especially in summer and autumn.
A humid subtropical climate is characteristic of the eastern coasts of continents north and south of the tropics. The main areas of distribution are the southeastern United States, some southeastern parts of Europe, northern India and Myanmar, eastern China and southern Japan, northeastern Argentina, Uruguay and southern Brazil, the coast of Natal in South Africa and the eastern coast of Australia. Summer in humid subtropics long and hot, with temperatures similar to those in the tropics. The average temperature of the warmest month exceeds +27° C, and the maximum – +38° C. Winters are mild, with average monthly temperatures above 0° C. In the humid subtropics, average annual precipitation ranges from 750 to 2000 mm, the distribution of precipitation by season is quite uniform. In winter, rain and rare snowfalls are brought mainly by cyclones. In summer, precipitation falls mainly in the form of thunderstorms associated with powerful inflows of warm and humid oceanic air, characteristic of the monsoon circulation of East Asia. Hurricanes (or typhoons) occur in late summer and fall, especially in the Northern Hemisphere.
Subtropical climate with dry in summer it is typical for the western coasts of continents north and south of the tropics. IN Southern Europe and North Africa, such climatic conditions are typical for the coasts Mediterranean Sea, which gave rise to calling this climate also Mediterranean. The same climate in southern California, central regions Chile, southernmost Africa and parts of southern Australia. All these areas have hot summers and mild winters. As in the humid subtropics, there are occasional frosts in winter. In inland areas, summer temperatures are significantly higher than on the coasts, and are often the same as in tropical deserts. In general, clear weather prevails. In summer, on the coasts near which they pass ocean currents, there are often fogs. The maximum precipitation is associated with the passage of cyclones in winter, when the prevailing westerly air currents shift towards the equator. The influence of anticyclones and downward air currents under the oceans determine the dryness of the summer season. Average annual precipitation under conditions subtropical climate ranges from 380 to 900 mm and reaches maximum values on the coasts and mountain slopes. In summer there is usually not enough rainfall for normal tree growth, and therefore a specific type of evergreen shrubby vegetation develops there, known as maquis, chaparral, mali, macchia and fynbos.
Semi arid climate temperate latitudes (synonym: steppe climate) is characteristic mainly of inland areas remote from the oceans (sources of moisture) and usually located in the rain shadow high mountains. The main areas with a semiarid climate are the intermountain basins and Great Plains of North America and the steppes of central Eurasia. Hot summers and cold winters are due to the inland location in temperate latitudes. At least one winter month has an average temperature below 0° C, and the average temperature of the warmest summer month exceeds +21° C. The temperature regime and the duration of the frost-free period vary significantly depending on the latitude. The term "semiarid" is used to characterize this climate because it is less dry than the arid (dry) climate proper. The average annual precipitation is usually less than 500 mm, but more than 250 mm. Since for the development of steppe vegetation in conditions more high temperatures more precipitation is needed, the latitudinal-geographical and altitudinal position of the area determine climate change. For a semiarid climate, there are no general patterns of precipitation distribution throughout the year. For example, areas bordering the subtropics with dry summers experience maximum rainfall in winter, while areas adjacent to humid continental climates experience rainfall primarily in summer. Temperate cyclones bring most of the winter's precipitation, which often falls as snow and can be accompanied by strong winds. Summer thunderstorms often occur with hail. The amount of precipitation varies greatly from year to year.
The arid climate of temperate latitudes is characteristic mainly of the Central Asian deserts, and in the western United States - only small areas in intermountain basins. Temperatures are the same as in areas with a semiarid climate, but precipitation here is insufficient for the existence of a closed natural vegetation cover and average annual amounts usually do not exceed 250 mm. As in semiarid climatic conditions, the amount of precipitation that determines aridity depends on the thermal regime.
The semiarid climate of low latitudes is mainly typical for the outskirts tropical deserts(for example, the Sahara and deserts of central Australia), where downdrafts of air in subtropical high pressure zones exclude precipitation. The climate under consideration differs from the semiarid climate of temperate latitudes in very hot summers and warm winters. Average monthly temperatures are above 0°C, although frosts sometimes occur in winter, especially in areas furthest from the equator and located at high altitudes. The amount of precipitation required for the existence of closed natural herbaceous vegetation is higher here than in temperate latitudes. In the equatorial zone, rain falls mainly in the summer, while on the outer (northern and southern) outskirts of the deserts the maximum precipitation occurs in winter. Most precipitation falls in the form of thunderstorms showers, and in winter rains brought by cyclones.
Arid climate of low latitudes.
This is a hot, dry tropical desert climate that extends along the Northern and Southern Tropics and is influenced by subtropical anticyclones for most of the year. Relief from the sweltering summer heat can only be found on the coasts, washed by cold ocean currents, or in the mountains. On the plains, average summer temperatures noticeably exceed +32° C, winter temperatures are usually above +10° C. In most of this climatic region, the average annual precipitation does not exceed 125 mm. It happens that at many meteorological stations no precipitation is recorded at all for several years in a row. Sometimes the average annual precipitation can reach 380 mm, but this is still only enough for the development of sparse desert vegetation. Occasionally, precipitation occurs in the form of short, strong thunderstorms, but the water drains quickly to form flash floods. The driest areas are located along the western coasts of South America and Africa, where cold ocean currents prevent the formation of clouds and loss precipitation. These coasts often experience fog, formed by the condensation of moisture in the air over the colder surface of the ocean.
Variably humid tropical climate.
Areas with such a climate are located in tropical sublatitudinal zones, several degrees north and south of the equator. This climate is also called tropical monsoon climate, as it prevails in those parts of South Asia that are influenced by monsoon. Other areas with such a climate are the tropics of Central and South America, Africa and Northern Australia. Average summer temperatures are usually around +27° C, and winter temperatures are around +21° C. The most hot month, as a rule, precedes summer season rains. Average annual precipitation ranges from 750 to 2000 mm. During the summer rainy season, the intertropical convergence zone has a decisive influence on the climate. There are frequent thunderstorms here, sometimes overcast with lingering rains persists for a long time. Winter is dry, as subtropical anticyclones dominate this season. In some areas, rain does not fall for two or three winter months. In South Asia, the wet season coincides with the summer monsoon, which brings moisture from the Indian Ocean, and in winter the Asian continental dry air masses spread here.
Humid tropical climate
or humid climate tropical forests, common in equatorial latitudes in the Amazon basin in South America and the Congo in Africa, on the Malay Peninsula and on the islands South-East Asia. In the humid tropics, the average temperature of any month is not less than +17 ° C, usually the average monthly temperature is about +26 ° C. As in the variable-humid tropics, due to the high midday position of the Sun above the horizon and the same day length throughout the year, seasonal variations temperatures are low. Moist air, cloud cover and dense vegetation prevent night cooling and keep maximum daytime temperatures below 37°C, lower than at higher latitudes.
The average annual precipitation in the humid tropics ranges from 1500 to 2500 mm, and the seasonal distribution is usually fairly even. Precipitation is mainly associated with the Intertropical Convergence Zone, which is located slightly north of the equator. Seasonal shifts of this zone to the north and south in some areas lead to the formation of two maximum precipitation during the year, separated by drier periods. Every day, thousands of thunderstorms roll over the humid tropics. In between, the sun shines in full force.
Highland climates.
In high mountain areas, a significant variety of climatic conditions is due to the latitudinal geographic position, orographic barriers and different exposures of slopes in relation to the Sun and moisture-carrying air flows. Even on the equator in the mountains there are migrating snowfields. The lower limit of eternal snow descends towards the poles, reaching sea level in the polar regions. Like it, other boundaries of high-altitude thermal belts decrease as they approach high latitudes. The windward slopes of mountain ranges receive more precipitation. On mountain slopes exposed to cold air intrusions, temperatures may drop. In general, the climate of the highlands is characterized by lower temperatures, higher cloudiness, more precipitation and a more complex wind regime than the climate of the plains at the corresponding latitudes. Character seasonal changes Temperatures and precipitation in the highlands are usually the same as in the adjacent plains.
Climatic zones and local climate features.
At the end of the 18th century. student of M.V. Lomonosov and one of the first Russian academicians I.I. Lepekhin, outlined general scheme placement of vegetation and fauna on the earth's surface of the world, depending on thermal (climatic) zones. At the beginning of the 19th century. German naturalist and traveler A. Humboldt established zonation and altitudinal zone vegetation due to changes in the amount of heat coming to the Earth.
Initially, 5 climatic zones were distinguished on the surface of the Earth: one hot, located on both sides of the equator between the northern and southern tropical circles; two temperate ones - between the tropical and polar circles and two cold ones, located around the North and South Poles.
Later, when enough information was accumulated about the temperature of the earth's surface in various parts of our planet, the number of climate zones increased to 7, and the boundaries between them began to be considered not the astronomical tropical and polar circles, but lines of equal average temperatures (isotherms). The boundary of the hot zone began to be considered the average annual isotherm of 20°, of the temperate zones - the isotherm of the warmest month of the year +10°. From the cold belts, two more zones of perpetual frost were identified, the boundary between which was drawn according to the isotherm of the warmest month of the year, 0°.
If the Earth's rotation axis were perpendicular to the plane of its orbit (i.e. to ecliptic), then at each geographic latitude exposure to solar radiation would always remain unchanged. In the polar zones, due to the oblique incidence of solar rays, the heating of the Earth's surface would be maximally different from the heating of the equatorial zone by normally incident solar rays. Then the climate on the entire Earth would depend most on geographic latitude (i.e., the angular distance from the equator). The relatively small tilt of the Earth's axis of rotation leads to a change in the flux of radiation from the Sun at each latitude throughout the year (i.e., during the Earth's revolution around the Sun). This change is especially pronounced at the poles (polar zones ), in which the length of the night exceeds the day. On the contrary, near the equator the Sun may culminate at its zenith. Depending on the limits of possible positions of the Sun above the horizon during the year, it is conventionally accepted to divide the Earth into thermal zones: hot (between the latitudes of the tropics from –23.5° to +23.5°) and two cold ones, in which the northern and southern latitudes exceed 66.5°. The rest of the Earth is between hot and cold, called temperate zones. Now, using data on temperature and the amount of incoming solar energy (radiation), 13 climatic zones are distinguished, which are usually called geographical: Arctic, Antarctic, subarctic, subantarctic, temperate northern and southern, subtropical northern and southern, tropical northern and southern, subequatorial northern and southern, equatorial. Climatic zones, depending mainly on geographic latitude, are clearly visible both on land and in the ocean.
Air temperature.
Air temperature - the degree of air heating, determined using thermometers and thermographs, is one of the most important characteristics of weather and climate, which has a direct impact on humans, animals, plants, the operation of mechanisms, etc. The maximum temperature of +58°C was recorded in September 1922 in the Tripoli area (North Africa), the minimum temperature was –89°C in July 1983 at the Vostok station in Antarctica.
Air temperature largely depends on how the sun's rays hit a given area of the earth's surface. The surface warms up and begins to transfer heat to the atmosphere. The temperature difference creates differences in air pressure on the earth's surface. Pressure differences create air movement called by the wind. Zones of high and low pressure appear. When there is a difference in atmospheric pressure, air moves from areas of high pressure to areas of low pressure to equalize the pressure across the entire surface.
Areas of high and low pressure constantly move across the earth's surface, creating air movement and carrying air masses with them. When two air masses meet different characteristics the air cannot move freely, and a kind of boundary is formed between them, called an atmospheric front. The weather in areas affected by atmospheric fronts is accompanied by cloudiness, precipitation, increased wind speed and a sharp change in air temperature.
Passing through earth's atmosphere and meeting clouds, dust and water vapor on its way, the sun's rays are partially absorbed or reflected into space. Only about 40% of solar energy reaching the earth's surface reaches upper limit atmosphere. At the same time, the incoming radiant energy of the Sun provides the earth's surface with light, heat and energy for almost all chemical transformations of earth's matter that occur on the earth's surface. The amount of incoming solar energy naturally decreases from the equator to the poles, depending on the angle of incidence of the sun's rays and the length of their path through the atmosphere. Atmospheric heat also changes in the same direction.
The surface of the Earth has a different reflectivity of the sun's rays falling on it (value albedo). For this reason, different parts of the surface absorb heat differently and become hotter. Uneven heating of the earth's surface sets in motion air and water masses, trying to equalize the temperature. Interconnected air And sea currents move from place to place great amount heat. Warm and cold sea currents play a particularly important role in the transfer (advection) of heat, since water absorbs and accumulates much more heat than air. Therefore, stronger deviations from average temperatures are observed on sea coasts.
Seasonal climate phenomena.
Due to uneven distribution solar heat and atmospheric precipitation on the earth's surface, the Earth's climate is very diverse. The famous scientist B.P. Alisov identified 13 climate zones on Earth, which differ from each other in temperature conditions and air masses. The main climatic zones correspond to the distribution of four types of air masses. There are especially large temperature contrasts at the Earth's surface - between the equator and the poles due to the difference in the arrival of solar energy at different latitudes. In the region of the equator there is an equatorial climate zone. Equatorial air and low atmospheric pressure predominate here. Tropical air, high pressure, and downward air movement dominate in tropical zones. In temperate zones, westerly winds predominate. It is much colder here than in tropical zones. Transition belts are located between the remaining belts. The prefix "sub" in Latin means "under". Subequatorial belt - subequatorial belt, etc. IN transitional belts air masses change with the seasons. Temperature distribution is influenced by the location of continents and oceans. Due to the high heat capacity and thermal conductivity of ocean waters, the oceans significantly attenuate the temperature fluctuations that arise as a result of changes in the arrival of solar radiation throughout the year. In this regard, in the middle and high latitudes, the air temperature over the oceans in summer is noticeably lower than over the continents, and higher in winter.
Weather forecasting.
Nowcasts (ranging from 0 to 6 to 12 hours) are based on an observationally intensive approach and are called nowcasts. Traditionally, nowcasting has focused on the analysis and extrapolation of observed meteorological fields, with particular emphasis on mesoscale cloud and precipitation fields derived from satellite and radar data. Nowcast forecast products are particularly valuable in the event of mesoscale severe weather conditions associated with strong convection and intense cyclones. In the case of tropical cyclones, nowcasting is an important approach to detection and subsequent short-term prediction, providing forecast validity beyond 24 hours in some cases.
The numerical (hydrodynamic) weather forecasting method is based on mathematical solution systems of complete equations of hydrodynamics and obtaining predictive fields of pressure and temperature for certain periods of time. Computing centers in Moscow, Washington, Tokyo, and Reiding (European Forecasting Center) use various numerical schemes for the development of large-scale atmospheric processes. The accuracy of numerical forecasts depends on the speed of calculation of computer systems, on the quantity and quality of information coming from weather stations. The more data, the more accurate the calculation.
The synoptic method of making weather forecasts is based on the analysis of weather maps. The essence of this method is a simultaneous review of the state of the atmosphere over a wide area, which makes it possible to determine the nature of the development of atmospheric processes and the most likely further change weather conditions in the area of interest. This review is carried out using weather maps on which the data is plotted meteorological observations at various heights, as well as at the surface of the earth, carried out simultaneously according to one program in various points globe. Based on a detailed analysis of these maps, the weather forecaster determines further conditions for the development of atmospheric processes in a certain period of time and calculates the characteristics of meteorological elements - temperature, wind, cloudiness, precipitation, etc.
Statistical forecasting methods make it possible to predict the weather condition for a certain period based on the past and present state of the atmosphere. future period time, i.e. predict changes in various weather elements in the future.
In operational practice, forecasters use several methods, which sometimes differ in a number of parameters, so the last word always remains with the forecaster, who chooses the best forecasting method, from his point of view. An integrated approach is often chosen - the use of several particular methods for forecasting the same characteristic of the state of the atmosphere at once in order to select the final formulation of the forecast.
Edward Kononovich
Literature:
Eris Chaisson, Steve McMillan Astronomy today. Prentice-Hall, Inc. Upper Saddle River, 2002
Materials on the Internet:
Mazur I.I., Rukin M.D. Weather analogy. Economics, 2003
http://science.nasa.gov
http://ciencia.nasa.gov/
http://www.noaa.gov/
Khabutdinov Yu. G., Shantalinsky K. M. Meteorology and climatology: The study of the atmosphere. Kazan University Publishing House, 2001.
http://spaceweather.com
In Russia, the climate classification of B.P. Alisov is used - it is the most logical and based on physical processes in the atmosphere, and above all on the distribution over to the globe air masses
Boris Pavlovich Alisov proposed to allocate climatic zones and areas, based on atmospheric circulation conditions. In his climatic zoning grid, seven climatic zones are identified in which climate formation all year round occurs under the predominant influence of air masses of only one type: equatorial, tropical, temperate (polar) and Arctic (in the southern hemisphere of the Antarctic) air. Between them, he distinguishes six transition zones, three in each hemisphere, characterized by seasonal changes in the prevailing air masses. These are two subequatorial zones, or tropical monsoon zones, in which equatorial air predominates in summer and tropical air in winter; two subtropical zones, in which tropical air predominates in summer and temperate air in winter; subarctic and subantarctic zones, in which temperate air predominates in summer and arctic and subantarctic air in winter.
Schematic map of the Earth's climate zones (according to B.P. Alisov)
The boundaries of the zones are drawn according to the average position of the main climate fronts. It is customary to distinguish a tropical, two temperate (polar), Arctic and Antarctic fronts. In each climate zone there are four main types of climate: continental, oceanic, climate of the western coasts and climate of the eastern coasts. In addition, due to relief conditions, mountain climates of the corresponding zone can be distinguished. Differences between continental and oceanic climates are due mainly to differences in the properties of the underlying surface; in the first case, these properties are created by continental air masses, in the second - by sea ones. The differences between the climate of the western and eastern coasts of the continents are mainly due to differences in conditions general circulation atmosphere and partly with the distribution of ocean currents.
Equatorial belt . Continental and oceanic types equatorial climate . These types of climate are very similar due to the dominance of homogeneous equatorial air. Temperatures throughout the entire zone are high all year round (+24... + 28 °C), and air humidity is high. There is a lot of precipitation - about 2000 mm. A significant amount of precipitation is caused not only by high absolute and relative air humidity, but also by its moisture-unstable stratification. Vertical instability is facilitated by the fact that the moist adiabatic gradients in it are less than the vertical temperature gradients. Seasonal fluctuations in average monthly temperatures on land (3-4°) and precipitation are insignificant. Two small maximum temperatures and precipitation (they are the result of thermal convection) occur after the days of the equinoxes, a slight decrease in temperatures and a decrease in precipitation occur after the days of the solstices. Daily temperature fluctuations on land reach 10-15°C. This is a zone of low pressure, rising air currents, and weak winds. In the narrow equatorial strip, weak westerly winds predominate. Over land that warms up quickly, convection develops during the day, powerful cumulonimbus clouds form, and in the afternoon there is heavy rain, usually accompanied by thunderstorms (the so-called zenithal rains). Over the sea, showers and thunderstorms occur at night. This is the main difference between the oceanic climate and the continental one; in addition, it has a very small daily and annual temperature range (2-3°C); excessive moisture. In the equatorial climate, moist evergreen forests grow on land.
Subequatorial belts. They are characterized by seasonal changes in air masses: the summer monsoon brings EV, the winter monsoon (trade wind) - TV.
Mainland monsoon climate. On land in summer it is hot (26-27°C) and humid, like at the equator, about 1500 mm of precipitation falls, the amount of which decreases with distance from the equator to 250-300 mm. In the same direction, the duration of the dry winter season increases from 2-3 months to six months. In winter, the temperature is about + 18... + 20°C, the humidity of the TV is low, there is no precipitation. In spring, the air temperature rises quickly and reaches a maximum of 30°C or more at the end of the dry season, for example in India - in May to 34-35°C. This is explained by a complex of reasons: the close to zenithal position of the Sun and a cloudless sky, which causes an abundance of solar radiation, as well as insignificant heat losses for evaporation, since after a dry winter the water reserves in the soil are small. Therefore, excess heat is spent on heating the air. As a result, there are three thermal seasons: a very hot spring, a hot summer-autumn period and a warm winter. This type of climate with wet summers and dry winters is called monsoon climate. Humidity is close to normal and slightly less than one. Grow variable-moist sparsely deciduous forests and savannas (from tall grass to xerophytic shrub and desert).
The climates of the continental coasts in the subequatorial zones differ little from the continental monsoon climate.
On the western coasts of the continents due to the coastal position and cold currents, temperatures in all seasons are 2-3°C less than inside the continents. The amount and regime of precipitation are the same.
Climate eastern coasts of continents differs from the continental one in that in winter the mTV (trade wind) flows in from the ocean from tropical high-pressure belts, but it is stably stratified. Therefore, there is almost no precipitation on the low coasts, and only on the mountainous coasts on the slopes of eastern exposure there is insignificant precipitation, the amount of which decreases with the height of the mountains. An example is the climate of the eastern coast of Brazil. Humidity conditions and natural vegetation zones are generally similar to inland areas.
Oceanic climate characterized by more even temperatures (25-22 °C), humid summers, dry winters. Annual precipitation is about 1500 mm. Tropical cyclones with hurricane-force winds and downpours often occur here in late summer and early autumn.
Tropical zones. Mainland tropical climate. It is developed on most of the continents. KTV dominates there all year round. Temperature in summer is +30... + 35°C, in winter about + 20°C. The daily air temperature range is 30-40°C, and on the sandy surface it reaches 80°C. The annual amplitude of air temperature is 10-15°C, which is less than the daily one. There is almost no precipitation. The lack of precipitation in winter is associated with lowering, adiabatic heating and drying of air in the high pressure zone. In summer there is no precipitation due to low relative humidity and high condensation levels. Only near the borders with subtropical zones in winter is cyclonic activity weakly developed and 100-200 mm of precipitation falls. At the borders with subequatorial belts the same amount of precipitation falls in summer due to the sometimes penetration of the summer equatorial monsoon. Moisturizing is negligible. Such a climate is called arid and even extra-arid. The greatest tropical deserts in the world are located here: the Sahara, the deserts of Arabia (Rub al-Khali, Greater and Lesser Nefud), Australia (Great Sandy, Great Victoria, Simpson deserts), the semi-desert of the Kalahari (in Africa).
The climate is peculiar western coasts of continents, where mTV predominates throughout the year. It moves along the eastern peripheries of subtropical oceanic highs from the colder temperate latitudes towards the equator over cold currents. In this regard, temperatures are usually low - about +20°C in summer and +15°C in winter. When moving to low latitudes, the air warms up and moves away from saturation. Oceanic pressure maxima with an inversion layer on the surface also do not contribute to the formation of clouds. high altitude due to the effect of latitude - about 1000 m. The inversion is enhanced by cold currents and the rise of cold waters in coastal zone upwelling, which causes the air near the surface of the ocean to be colder than in the upper layers. Inversion prevents the development of convection. However, the mW carried by strong daytime breezes to the coast contains a lot of water vapor. This increases the relative air humidity here to 83-85% and leads to the formation of dew and fog on the coasts at night. Humidity is negligible, so coastal deserts extend here. To designate the climate of coastal deserts washed by cold currents, the term “garua climate” is used (Spanish garua - dense drizzling fog).
On eastern coasts of continents, along which warm currents flow and above which the air receives a lot of moisture, the climate is different: high temperatures - +25...+28°C in summer, about +20°C in winter, quite a lot of precipitation - up to 1000 mm, especially in summer. Excessive moisture. In conditions humid climate Evergreen tropical forests grow in the tropical zone.
Oceanic climate The tropical belt is formed in areas of high pressure with an inversion layer and stable winds. There is spatial heterogeneity of climatic conditions, manifested in the regime of all elements. In the east of the oceans, above cold currents, air temperatures are +20...+ 15°C, there is little precipitation; in the western oceans due to warm currents temperatures rise to +25...+20°С, precipitation becomes 500–1000 mm. Tropical hurricanes are typical.
The listed climate zones lie mainly within the boundaries of the hot thermal zone, limited by annual isotherms of +20°C (winter temperatures +15°C). In these zones, temperature differences are very insignificant, therefore the main signs of seasonal changes in nature are the amount and regime of precipitation. The development of vegetation is limited here not by temperature, but by precipitation, and not just by its annual quantity, but by the duration of dry and wet periods. The extent of natural plant zones is different: sometimes latitudinal, sometimes meridional; it is also subject to the regularities of moisture conditions.
Subtropical zones. The climate is formed under the influence of seasonal changes in air masses: HF in summer, which is formed in the belt itself under the influence of high insolation, and HC in winter, coming from temperate latitudes.
Mainland subtropical climate– arid, with hot (about +30°C) dry summers and cool (0... +5°C), relatively wet (200-250 mm) winters, with unstable frontal weather. Humidification is insufficient, so natural zones of deserts, semi-deserts, and dry steppes predominate. In Eurasia, this climate is developed in the center of the continent, far from the oceans, especially in basins. In North America, it formed on the Colorado Plateau and southern Great Basin Highlands as a result of their orographic isolation from marine influence.
called Mediterranean, since it is most typical for the Mediterranean coast (Southern Europe, Western Asia, North Africa), although there are areas with such a climate on other continents. It is characterized by relatively hot temperatures (more than + 20°C) dry summer with an anticyclonic weather regime, mild (about +10°C) wet (500-700 mm) winter with frontal precipitation and unstable weather. Vegetation – dry-loving evergreen hard-leaved forests and shrubs. Currently, vineyards, citrus plantations and other subtropical crops predominate.
The climate of the eastern coasts of the continents is monsoon, it is best expressed in Eurasia. In summer, a stable monsoon from the ocean (mTV) prevails, it is hot (+25°C), and humid. At the end of summer - beginning of autumn, typhoons from the sea with gusty winds and heavy precipitation are frequent. Winter is relatively cool (on average 0... +5°С, but in some places below 0°С) and relatively dry, since the monsoon from the land from seasonal baric highs, in particular from the Asian one, brings HF. But near the coasts and on the islands, frontal precipitation occurs even in winter. Total precipitation is about 1000 mm. Sufficient hydration. Vegetation – variable-moist deciduous broad-leaved and mixed forests. The degree of agricultural development is high.
Oceanic The climate in terms of precipitation regime is reminiscent of the Mediterranean - summers are relatively dry, winters are wet with frontal precipitation. The temperature in summer is about 20°C, in winter 15°C.
The subtropical zone as a whole is characterized by predominantly positive (according to long-term data) temperatures throughout the year. However, in winter, short-term drops in temperature to negative values and even snowfall are possible here, especially in monsoon climate. On the plains it melts quickly; in the mountains it can persist for up to several months. The exception is the largest and highest (4-5 km) highland in the world, Tibet, located in this belt. It is characterized by a special type of sharply continental climate: cool summers, harsh winters, and little precipitation. Highland deserts are developed in the highlands.
Temperate zones. In these belts, HC dominates throughout the year, but invasions of both TV (especially in summer) and AW (in summer and winter) are possible. In these belts, the radiation balance is peculiar: in summer it is positive due to the rather high altitude of the Sun and the significant length of the day, in winter it is negative due to the low altitude of the Sun, short daylight hours, high reflectivity of snow. Feature belts - intense cyclonic activity on fronts both between TV and SW, SW and AB, and between SW and SW. It is associated with instability of weather conditions, especially in winter.
Mainland climate– moderately continental and sharply continental; expressed only in the northern hemisphere - in Eurasia and North America. The CUV dominates, and MUV invasions from the west are not uncommon. On average, the temperature of the warmest summer month of July varies from +12°C in the north to +25... + 28°C in the south, the coldest - January - from -5°C in the west to -25...-30° C in the center of the continents, and in Yakutia even below –40°C. Low winter soil and air temperatures and small amounts of snow in Eastern Siberia support the existence of permafrost. Annual precipitation decreases from west to east from 700-600 mm to 300 mm and even to 200-100 mm in the Middle and Central Asia. In North America, precipitation decreases from east to west. In summer there is more precipitation than in winter, and this difference is more significant in the center of the continents, especially in Eastern Siberia, due to the very dry anticyclonic winter. Precipitation of frontal origin predominates: in summer it falls from the local SWM, in winter – from the incoming warmer SWW. In summer, convective precipitation also occurs, and in front of the mountains (for example, in front of the Tien Shan, Altai) there is orographic precipitation. Due to the large extent of the belt from north to south, it is often distinguished as a northern boreal part with cool summers and relatively harsh winter(coincides with the taiga) and the southern subboreal part with warm summer and relatively mild winters. According to the degree of continentality of the climate, expressed primarily by the annual temperature amplitude, its varieties are distinguished: from moderate continental to sharply continental. Humidification varies from excessive in the north to severely insufficient in the south. Therefore, there is a rich range of natural vegetation zones: taiga, mixed and broadleaf forests, forest-steppe, steppe, semi-desert, desert.
Climate of the western coasts of the continents is formed under the influence of the ISW formed over warm currents and brought by the prevailing westerly winds. That's why they call him maritime climate. It is characterized by cool summers (+10°C in the north, +17°C in the south), mild winters with temperatures from 0 to +5°C. In winter in the north, temperatures drop to negative values and snowfalls are common. There is a lot of precipitation - 800-1000 mm, in front of the mountains up to 1500 mm (southwest of Scandinavia) and even 3000 mm (western slopes of the Cordillera and Andes). The predominant precipitation is frontal and orographic. Excessive moisture. Coniferous and broad-leaved forests grow.
The climate of the eastern coasts of Asia is monsoon. There is a seasonal change in air masses here: in summer there is a warm and humid IHC, in winter there is a very cold and dry IHC from the Asian High. Accordingly, the temperature is about +20°C in summer and –10... –20°C in winter. The amount of summer precipitation is 10-20 times greater than winter, and its total amount varies from 500 to 1000 mm depending on the orography: there is more precipitation on the eastern slopes of the mountains. Excessive moisture, mixed and coniferous forests. This climate is best expressed in the Primorsky Territory of Russia and Northeast China. In North America, the circulation of air masses is monsoonal, but the climate is uniformly humid.
Oceanic climate expressed in the North Atlantic and Pacific Ocean and in the southern hemisphere. In summer temperatures are about + 12...+ 15°C, in winter +5... +8°C. Precipitation falls throughout the year, its annual amount is about 1000 mm. In the southern hemisphere temperate zone The oceanic climate with mild summers, mild winters, heavy frontal precipitation, westerly winds, and unstable weather (“roaring” forties latitudes) almost completely dominates. Temperatures here are lower than in the northern hemisphere.
Subarctic and subantarctic belts. They are characterized by seasonal changes in air masses: in summer, hydrocarbons are common here, and in winter, air masses are widespread.
Continental, including sharply continental, the climate is observed only in the northern hemisphere in northern Eurasia and North America. Air circulation is monsoonal. In summer from the North Arctic Ocean AB arrives, which, under polar day conditions, is transformed into a SW. In winter from the baric Asian and Canadian highs southerly winds bring very cold cSW, which, under polar night conditions, cools even more and acquires the properties of cSW. Summer is short, cool, with temperatures less than +10...+12°C and damp. Winter is severe (–40...–50°С), long, with little snow. In this belt - in Yakutia in the intermountain basin - the cold pole of the northern hemisphere is located - the village. Oymyakon, where the winter temperature was recorded at -71°C. The belt is characterized by large annual temperature amplitudes - up to 60-70°C. Precipitation – 200-100 mm, frontal – on the Arctic (Antarctic) front. Permafrost, excessive moisture, and large swamps are widespread. Typical zones are tundra and forest-tundra.
Marine (oceanic) climate t is found in northern Europe, in the coastal seas of the Arctic Ocean (Barents, Greenland Sea), around Antarctica. Characterized by cool summers (+3... +5°С), floating sea and continental ice, relatively mild (–10...–15°С) winter. Precipitation is up to 500 mm, fog is constant. Along the coasts northern continents and the tundra extends across the islands. In the southern hemisphere, on the islands around Antarctica there are meadows with sparse herbaceous vegetation.
Arctic and Antarctic belts. They are dominated by continental climate: in Antarctica, Greenland, on the islands of the Canadian archipelago. There are negative temperatures here all year round. In Antarctica, at the Vostok inland station, at an altitude of more than 3 km, an absolute minimum temperature of –89.2°C was recorded. Precipitation is less than 100 mm. Ice deserts are typical. Oceanic climate observed mainly in the Arctic. Temperatures here are negative, but during the polar day they can reach +2°C. Precipitation is 100-150 mm, but when cyclones penetrate there it becomes more. The islands are characterized by tundra with sparse moss and lichen cover.
Climate plays a huge role in the nature of the Earth. The moisture content of the area depends on it. It determines the nature of vegetation, fauna, soil cover, the regime of rivers, lakes, seas, glaciers, the formation of some rocks, influences the formation of the relief. Climate must be taken into account economic activity people, especially in agriculture, as well as in construction, industry, and transport. Climate and weather are of great importance for human health and activity.
Literature
- Lyubushkina S.G. General Geography: Textbook. a manual for university students studying specialties. "Geography" / S.G. Lyubushkina, K.V. Pashkang, A.V. Chernov; Ed. A.V. Chernova. - M.: Education, 2004. - 288 p.
Hello dear friends! It's time again for some new and interesting information. 🙂 I think that an article on the topic of what types of climate there are will help you decide on a vacation in all seasons.
In winter, rain and rare snowfalls are mainly caused by cyclones. Hurricanes (or typhoons) occur in late summer and autumn, especially in the Northern Hemisphere.
This type of climate is typical of the west coast of continents in the south and north of the tropics. In North Africa and Southern Europe, such climatic conditions are characteristic of the Mediterranean coast, which also allows this climate to be called Mediterranean.
This type of climate is also found in central Chile, southern California, the extreme south of Africa and in several areas in southern Australia.
In these areas, summers are hot and winters are mild. In winter, just as in the humid subtropics, there are occasional frosts.
In the summer, temperatures in inland areas are significantly higher than on the coast, and are often the same as in tropical deserts. Also in summer, fog often occurs on the coast near which ocean currents pass.
The passage of cyclones in winter, when westerly air currents shift toward the equator, is associated with maximum precipitation. The dryness of the summer season is determined by the influence of anticyclones and declining air flows over the oceans.
In a subtropical climate, the average annual precipitation ranges from 380 mm to 900 mm, and reaches maximum values on the mountain slopes and on the coast.
In summer, there is usually not enough rainfall for normal tree growth, so a specific type of evergreen shrubby vegetation develops there, known as mali, maquis, macchia, chaparral and fynbos.
Semiarid climate of temperate latitudes.
A synonym for this type of climate is steppe climate. It is mainly characteristic of inland areas that are distant from the oceans - sources of moisture - and mainly located in the rainy shadow of high mountains.
The main areas with a semiarid climate are the Great Plains and intermountain basins of North America and the steppes of central Eurasia. Its inland location in temperate latitudes results in cold winters and hot summers.
The average temperature is below 0°C in at least one winter month, and the average temperature of the warmest summer month exceeds 21°C. Depending on the latitude, the temperature regime and the duration of the frost-free period change significantly.
The term “semiarid” is used to characterize this climate, because this climate is less dry than the arid climate proper. The annual amount of precipitation is partly more than 500 mm, but not less than 250 mm.
Since the development of steppe vegetation in conditions of higher temperatures requires more precipitation, the latitudinal-geographical and altitudinal position of the area determine climatic changes.
Throughout the year, there are no general patterns of precipitation distribution for a semiarid climate. For example, in those areas adjacent to areas of humid continental climate, precipitation occurs mainly in the summer, and in areas bordering the subtropics with dry summers, maximum precipitation occurs in winter.
Most of the winter precipitation comes from mid-latitude cyclones. They often fall in the form of snow and can also be accompanied by strong winds. Summer thunderstorms often include hail.
Semiarid climate of low latitudes.
This type of climate is characteristic of the edges of tropical deserts (for example, the deserts of central Australia and the Sahara), where downdrafts of air in subtropical high pressure zones exclude precipitation.
This climate differs from the semiarid climate of temperate latitudes with warm winters and very hot summers. Average monthly temperatures are above 0°C, although sometimes there are frosts in winter, especially in those areas that are furthest from the equator and located at high altitudes.
Here, the amount of precipitation that is necessary for the existence of closed natural herbaceous vegetation is higher than in temperate latitudes. On the outer (southern and northern) outskirts of deserts, maximum precipitation falls in winter, while in the equatorial line rain falls mainly in summer.
Precipitation mainly falls in the form of thunderstorms, and in winter the rains are brought by cyclones.
Arid climate of temperate latitudes.
This type of climate is mainly characteristic of the Central Asian deserts, and in the west - only for small areas in intermountain basins.
The temperatures here are the same as in the semiarid climate regions, but there is not enough precipitation for the existence of a closed natural vegetation cover and usually the average annual precipitation does not exceed 250 mm.
The amount of precipitation, which determines aridity, as in semiarid conditions, depends on temperature regime.
Arid climate of low latitudes.
It's dry and hot climate tropical deserts that stretch along the Southern and Northern tropics, and for a significant part of the year are under the influence of subtropical anticyclones.
Only in the mountains or on the coast, which is washed by cold ocean currents, can one find salvation from the debilitating summer heat. Summer temperatures on the plains noticeably exceed 32°C, and winter temperatures, as a rule, are above 10°C.
The average annual precipitation in most of this climatic region does not exceed 125 mm. It even happens that for several years in a row, many meteorological stations do not record precipitation at all.
The average annual precipitation can reach 380 mm, but this is only sufficient for the development of sparse desert vegetation.
The driest areas are located along the western coasts of Africa and South America, where precipitation and cloud formation are hindered by cold ocean currents.
Fogs are a common occurrence on this coast. They are formed by the condensation of moisture in the air over the colder surface of the ocean.
Variable humid tropical climate.
Areas of this type of climate are tropical sublatitudinal zones several degrees south and north of the equator. This climate is also called tropical monsoon climate because it prevails in those parts of South Asia that are under the influence of monsoons.
Other areas of this type of climate are the tropics of Northern Australia, Africa, South and Central America. Average temperatures in winter are around 21°C, and in summer they are usually around 27°C. Typically, the hottest month precedes the summer rainy season.
The average annual precipitation ranges from 750 mm to 2000 mm. The intertropical convergence zone has a decisive influence on the climate during the summer rainy season. There are often thunderstorms here, and sometimes, for a long period, there is continuous cloudiness with lingering rains.
Since this season is dominated by subtropical anticyclones, winter is dry. Rain in some areas does not fall for two or three winter months. The wet season in South Asia coincides with the summer monsoon, which brings moisture from the Indian Ocean, and in winter the Asian continental dry air mass spreads here.
This climate is also called tropical rainforest climate. It is distributed in equatorial latitudes in the Amazon basin in South America and the Congo in Africa, on the islands of Southeast Asia and on the Malacca Peninsula.
The average temperature of any month in the humid tropics is at least 17°C, and the average monthly temperature is about 26°C. As in the variably humid tropics, due to the same length of day throughout the year and the high midday solstice above the horizon, seasonal temperature fluctuations are small.
Dense vegetation cover, cloud cover and humid air interfere with nighttime cooling and keep maximum daytime temperatures below 37°C. In the humid tropics, the average annual precipitation ranges from 1500 mm to 2500 mm.
Precipitation is predominantly associated with the intertropical convergence zone, which is located slightly north of the equator. In some areas, seasonal shifts of this zone to the south and north lead to the formation of two maximum precipitation throughout the year, which are separated by drier periods. Thousands of thunderstorms pass over the humid tropics every day.
Highland climate.
Significant in high mountain areas is due to the latitudinal geographic position, different exposures of slopes in relation to moist air currents and the Sun, and orographic barriers.
Sometimes, even at the equator, snow falls in the mountains. The lower limit of eternal snow descends towards the poles, reaching sea level in the polar regions. The windward slopes of mountain ranges receive more precipitation.
A decrease in temperature can be observed on mountain slopes that are open to cold air intrusions.
In general, this type of climate is characterized by higher cloud cover, lower temperatures, more complex wind patterns and greater precipitation than lowland climates at similar latitudes. The pattern of precipitation and seasonal changes here is usually the same as on the adjacent plains.
This was a description of climate types, which, I hope, greatly helped you understand this issue. See you again on the blog pages!
Characteristics of climatic zones (the table below) is the topic of this article. We will talk about what types of climate exist on our planet, and also consider each of them in detail. To do this, let us recall that climate is the weather regime established over the years, which depends on a specific territory and its geographical location.
Equatorial belt
This climate zone is characterized by low pressure, as well as the year-round presence of air masses. There are no separate climatic regions within the belt. As for the temperature, it is hot here. There is a lot of precipitation throughout the year and there is plenty of moisture. The weather here changes very dramatically during the day. The first half is sultry, and the second half begins with heavy rains.
The names of climate zones are associated with their characteristics. The equatorial belt is located near the equator, which is why it has this name.
The subequatorial belt is characterized by changes in air masses that occur seasonally. In summer, equatorial air masses predominate, and in winter, more tropical ones. Weather conditions in summer fully correspond to the equatorial type of climate, while the weather in winter resembles the conditions of the tropical zone. Winter is dry and slightly colder than summer.
Tropical zone
As we already know, the names of climate zones are associated with their location. This type of climate is characterized by tropical air masses all year round. The air is continental. Real tropical weather is high pressure and temperature, a big difference temperatures not only throughout the year, but also throughout the day. Water is very scarce in this climate. It is very hot and dry here, and dry winds often occur. There is almost no rain. The weather is usually dry and sunny.
However, the tropical belt is deceptive. The eastern shores of the continents, which are washed by warm currents, are also in this zone, but have a different climate. Marine tropical air, heavy rainfall, monsoons. Climatic conditions are similar to the equatorial climate.
For subtropical zones characterized by a change in air masses. The climate is tropical in summer and temperate in winter. Pressure surges in summer and winter are quite high. In winter the pressure is low and in summer it is high. Despite the strong differences in temperature and precipitation throughout the year, the thermometer is above zero the entire year. Sometimes the temperature can even drop to negative values. During such periods snow falls. In flat areas it melts quickly, but in the mountains it can remain for several months. As for the winds, the trade winds rule in winter and the trade winds in summer.
Temperate zone
The temperature of climatic zones largely depends on the air masses that prevail over the territory. The temperate zone, as the name suggests, has a temperate climate. But not always. Sometimes tropical or arctic air masses invade. Temperate climate characterized by large temperature differences. Summers are hot, and winters are cold and long. Relatively low pressure, cyclones, unstable weather conditions in winter. Westerly winds blow throughout the year, with occasional trade winds in summer and north-easterly winds in winter. Massive snow cover every winter.
Arctic and Antarctic belts
In the characteristics of climate zones in the table, you can see what temperatures prevail in these zones. The features of these belts are: low temperatures oh all year round, strong winds and cold summers. There is very little precipitation.
Subarctic and subantarctic belts
These zones are distinguished by the fact that in summer a temperate climate prevails here. Because of this, a large amplitude of temperature fluctuations occurs. There is a lot in these belts permafrost. In winter, north-east and south-east winds predominate, and in summer - westerlies. There are 2 belts climatic regions, about them below.
Territories of climate zones
Each belt is characteristic of a specific territory. Natural climatic zones have been formed on the planet for a long time, so we can confidently identify certain areas in which the climate of the zone is pronounced.
The equatorial climate is characteristic of Oceania, South America and Africa. Subequatorial climate is typical for Northern Australia and Southeast Asia. central part Australia and North Africa are a tropical zone. Subtropics are characteristic of the interior regions of continents. A temperate climate prevails in the western part and eastern outskirts of Eurasia. the belt predominates in North America and northern Eurasia. The Arctic and Antarctic belts are characteristic of Australia and the Arctic Ocean.
Table of climate zones
The table shows the characteristics of the zones.
Belt | Average temperature in January | Average temperature in July | Atmosphere |
Equatorial | Moist warm air masses |
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Subequatorial | Monsoons prevail |
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Tropical | |||
Subtropical | Cyclonicity, high atmospheric pressure |
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Moderate | Western winds and monsoons |
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Subarctic | |||
Arctic (Antarctic) | Anticyclones |
Climatic regions of the belts
Subtropical zones have three climatic regions:
- Mediterranean climate. Prevails in the northern hemisphere, on the southern and western shores of continents. In summer there is a continental climate, and in winter there are continental and maritime air masses. Summers are dry and warm, and winters are relatively cool and wet. Insufficient hydration.
- Monsoon climate. Distributed on the eastern shores of continents. Summer monsoons cause extreme heat and a lot of rainfall, and the winter monsoons are cool and dry. Humidity in this area is moderate. Precipitation is typical for the winter season.
- Marine climate. Distributed on the continents of the southern hemisphere. Marine air masses are characteristic. Summer and winter are warm. There is enough moisture, it is distributed evenly throughout the year.
The temperate zone consists of 5 climatic regions:
- Moderate Prevails on the western shores of continents. The weather is formed under the influence of warm currents and western winds. Winters are quite mild and summers are warm. There will be a lot of precipitation throughout the year. Winter is characterized by heavy and frequent snowfalls. There is more than enough moisture. The geography of the climate zone contributes to weather instability.
- Continental temperate climate. Characterized by warm summers and cold winters. Arctic air masses sometimes provoke cold snap, and tropical air masses - warming. There is little precipitation, it is uniform (cyclonic and frontal).
- Continental climate. Applies only to North hemisphere. Moderate air masses prevail here throughout the year. Sometimes arctic air masses appear (in this area their invasion is possible even in summer). In the warm season there is more precipitation, but in general it is insignificant. A small amount of snow and the predominance of low temperatures contribute to the existence of permafrost.
- Sharply continental climate. Characteristic of the interior regions of North America and Eurasia. The territory is practically isolated from the influence of seas and oceans and is located in the center of high pressure. Sometimes summer is hot, winter is always frosty. There is a lot of permafrost. Weather type - anticyclonic. There is little precipitation and little moisture.
- Monsoon climate. Distributed on the eastern side of continents. Characterized by the seasonality of air masses. Summers are humid and warm, while winters are dry and cool. Summer precipitation is more numerous and there is excess moisture.
The subarctic and subantarctic belts have two regions:
- continental climate (severe but short winters, little precipitation, swampy areas);
- oceanic climate (fog, high rainfall, mild winters and cool summers).
The characteristics of climatic zones in the table do not include two areas of the Arctic and Antarctic zones:
- continental (little precipitation, temperatures below zero all year);
- oceanic climate (cyclones, little precipitation, negative temperatures).
Temperatures in oceanic climates can rise to +5 during the polar day.
To summarize, let's say that the characteristics of climatic zones (in the table) are necessary for every educated person.
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