Maritime climate is the mode of precipitation. The relief of the earth's surface. In the northern hemisphere

Maritime climate, or oceanic climate- the climate of regions close to the sea, characterized by small daily and annual air temperature amplitudes, high relative humidity, cool summers and mild winters (in temperate latitudes), high cloudiness caused by intense cyclonic activity, strong winds. In a maritime climate, the time of the onset of the highest and lowest temperatures is delayed (compared to areas with a continental climate) by 1-2 months, and spring is colder than autumn. It is formed under the prevailing influence of oceanic spaces on the atmosphere.

Climate of London
Indicator	Jan.	Feb.	March	Apr.	May	June	July	Aug.	Sen.	Oct.	Nov.	Dec.	Year
Absolute maximum, °C	14,9	18,5	22,2	27,1	30,6	34,3	35,0	37,3	33,4	28,2	18,9	15,2	37,3
Average maximum, °C	7,7	8,0	10,9	13,8	17,3	20,4	22,9	22,5	19,2	14,9	10,7	7,9	14,7
Average temperature, °C	5,0	4,9	7,1	9,2	12,6	15,6	17,9	17,6	14,9	11,4	7,7	5,3	10,8
Average minimum, °C	2,4	2,1	4,0	5,3	8,3	11,3	13,4	13,3	11,1	8,2	4,8	2,6	7,2
Absolute minimum, °C	−16,6	−16,1	−11,1	−4,9	−2,4	1,4	2,4	0,2	−0,4	−5,7	−9,1	−16,1	−16,6
Precipitation rate, mm	56	41	42	42	51	45	44	49	48	69	57	55	599
Source: Weather and Climate

Varieties

Subtropical highland climate (Cwb)

This variety oceanic climate characteristic of high-mountain regions located in the tropical and subtropical zones of the Earth. As in other areas with an oceanic climate, the highlands of the tropics and subtropics are characterized by mild summers and much cooler winters compared to other areas located in the same latitudes. However, unlike other areas with an oceanic climate, the highlands of the tropics and subtropics experience drier weather during the winter. In general, the high-mountain subtropical climate is characterized by almost constant temperature throughout the year, snow falls extremely rarely. In these areas, the average monthly temperature does not exceed 22 °C (72 °F) , but does not fall below −3 °C (27 °F) . At the same time, the average temperature for at least one month is below 18 °C (64 °F) .

This type of alpine climate is typical for certain regions of southern, eastern and southeastern Africa, the Atlas Mountains, some high mountain regions of Southern Europe, Northern (Southern Appalachians), Central and South America, Southeast Asia and certain regions in the Himalayas. Also to areas with high mountain sub tropical climate include some areas of Australia, although they are characterized by higher average monthly temperatures.

Climate Mexico City
Indicator	Jan.	Feb.	March	Apr.	May	June	July	Aug.	Sen.	Oct.	Nov.	Dec.	Year
Absolute maximum, °C	28,2	29,3	33,3	33,4	33,9	33,5	30,0	28,4	28,5	28,9	29,3	28,0	33,9
Average maximum, °C	21,3	22,9	25,5	26,6	26,3	24,7	23,2	23,4	22,5	22,4	21,9	21,2	23,5
Average temperature, °C	13,6	15,0	17,4	18,7	19,0	18,5	17,4	17,5	17,1	16,2	14,9	13,9	16,6
Average minimum, °C	5,9	7,0	9,2	10,7	11,7	12,3	11,5	11,5	11,6	9,9	7,8	6,5	9,6
Absolute minimum, °C	−4,1	−4,4	−4	−0,6	3,7	4,5	5,3	6,0	1,6	0,0	−3	−3	−4,4
Precipitation rate, mm	9	9	13	27	58	157	183	173	144	61	6	8	787
Source: NOAA

Subpolar Oceanic Climate (Cfc)

Areas with a subpolar oceanic climate share common features of an oceanic climate, but due to their location at high latitudes, they are characterized by colder weather and frequent snowfalls compared to other regions with an oceanic climate. Average temperatures for only one to three months exceed 10 °C (50 °F). At the same time, average temperatures do not fall below -3 °C (26.6 °F) in any of the months of the year. The subpolar oceanic climate is typical for the coast of Iceland, part of the coastal regions of Norway (for example, the Lofoten Islands), the Faroe Islands, the Scottish Highlands, the islands of southern Alaska, the extreme south of Chile and Argentina, the Australian and Southern Alps

Climate of Reykjavik
Indicator	Jan.	Feb.	March	Apr.	May	June	July	Aug.	Sen.	Oct.	Nov.	Dec.	Year
Absolute maximum, °C	11,6	10,2	13	14,7	20,6	22,4	25,7	24,8	20,1	16,6	13,3	12	25,7
Average maximum, °C	2,5	2,8	3,4	6,1	9,7	12,4	14,2	13,6	10,9	7	4,2	3,1	7,5
Average temperature, °C	0	0,1	0,6	3	6,6	9,5	11,2	10,7	8	4,4	1,9	0,6	4,7
Average minimum, °C	−2,4	−2,4	−1,9	0,5	3,8	7	8,8	8,4	5,7	2,2	−0,5	−1,8	2,3
Absolute minimum, °C	−19,7	−19,4	−16,4	−16,4	−7,7	−0,7	1,4	−0,4	−4,4	−10,6	−15	−16,8	−19,7
rainfall rate,

The content of the article

CLIMATE, long-term weather patterns in the area. The weather at any given time is characterized by certain combinations of temperature, humidity, wind direction and speed. In some types of climate, the weather changes significantly every day or seasonally, in others it remains the same. Climate descriptions are based on statistical analysis of average and extreme meteorological characteristics. Like a factor natural environment climate influences the geographic distribution of vegetation, soils and water resources and hence land use and the economy. Climate also has an impact on living conditions and human health.

Climatology is the science of climate that studies the causes of the formation of different types of climate, their geographical location and the relationship between climate and other natural phenomena. Climatology is closely related to meteorology - a branch of physics that studies the short-term states of the atmosphere, i.e. weather.

CLIMATE FORMING FACTORS

The position of the earth.

When the Earth revolves around the Sun, the angle between the polar axis and the perpendicular to the plane of the orbit remains constant and amounts to 23° 30°. This movement explains the change in the angle of incidence of the sun's rays on the earth's surface at noon at a certain latitude during the year. The greater the angle of incidence of the sun's rays on the Earth in a given place, the more efficiently the Sun heats the surface. Only between the Tropics North and South (from 23° 30' N to 23° 30' S) Sun rays at certain times of the year they fall vertically to the Earth, and here the Sun at noon always rises high above the horizon. Therefore, in the tropics it is usually warm at any time of the year. At higher latitudes, where the Sun is lower above the horizon, the heating of the earth's surface is less. There are significant seasonal changes in temperature (which does not happen in the tropics), and in winter the angle of incidence of the sun's rays is relatively small and the days are much shorter. At the equator, day and night are always of equal length, while at the poles the day lasts the entire summer half of the year, and in winter the sun never rises above the horizon. The length of the polar day only partly compensates for the low position of the Sun above the horizon, and as a result, the summer here is cool. In dark winters, the polar regions quickly lose heat and become very cold.

Distribution of land and sea.

Water heats up and cools down more slowly than land. Therefore, the air temperature over the oceans has less daily and seasonal changes than over the continents. In coastal areas, where winds blow from the sea, summers are generally cooler and winters warmer than in interior areas continents at the same latitude. The climate of such windward coasts is called maritime. The interior regions of the continents in temperate latitudes are characterized by significant differences in summer and winter temperatures. In such cases, one speaks of a continental climate.

Water areas are the main source of atmospheric moisture. When winds blow from warm oceans to land, there is a lot of precipitation. Windward coasts tend to be higher relative humidity and cloudy and more days with fogs than in the interior regions.

Atmospheric circulation.

The nature of the baric field and the rotation of the Earth determine the general circulation of the atmosphere, due to which heat and moisture are constantly redistributed over the earth's surface. Winds blow from areas of high pressure to areas of low pressure. High pressure is usually associated with cold, dense air, while low pressure is associated with warm, less dense air. The rotation of the Earth causes air currents to deviate to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This deviation is called the Coriolis effect.

In both the Northern and Southern Hemispheres, there are three main wind zones in the surface layers of the atmosphere. In the intratropical convergence zone near the equator, the northeast trade wind converges with the southeast. Trade winds originate in subtropical areas of high pressure, most developed over the oceans. Air currents, moving towards the poles and deviating under the influence of the Coriolis force, form the predominant western transport. In the region of polar fronts of temperate latitudes, western transport meets cold air of high latitudes, forming a zone of baric systems with low pressure in the center (cyclones) moving from west to east. Although the air currents in the polar regions are not so pronounced, polar eastward transport is sometimes distinguished. These winds blow mainly from the northeast in the Northern Hemisphere and from the southeast in the Southern Hemisphere. Masses of cold air often penetrate temperate latitudes.

Winds in the areas of convergence of air currents form ascending air currents, which cool with height. Cloud formation is possible, often accompanied by precipitation. Therefore, in the intratropical convergence zone and frontal zones in the belt of predominant western transport, a lot of precipitation falls.

Winds blowing in higher layers of the atmosphere close the circulation system in both hemispheres. Air rising up in convergence zones rushes into areas of high pressure and sinks there. At the same time, with increasing pressure, it heats up, which leads to the formation of a dry climate, especially on land. Such downward air currents determine the climate of the Sahara, located in the subtropical high pressure belt in North Africa.

Seasonal changes in heating and cooling cause seasonal movements of the main baric formations and wind systems. Wind zones in summer shift towards the poles, which leads to changes in weather conditions at a given latitude. Thus, the African savannahs, covered with grassy vegetation with sparsely growing trees, are characterized by rainy summers (due to the influence of the intratropical convergence zone) and dry winters, when a high pressure area with descending air currents shifts to this territory.

Seasonal changes in the general circulation of the atmosphere are also affected by the distribution of land and sea. In summer, when the Asian continent warms up and a lower pressure area is established above it than over the surrounding oceans, the coastal southern and southeastern regions are affected by moist air currents directed from the sea to land and bringing heavy rains. In winter, air flows from the cold surface of the mainland to the oceans, and much less rain falls. These winds, which change direction with the seasons, are called monsoons.

ocean currents

are formed under the influence of surface winds and differences in water density due to changes in its salinity and temperature. The direction of the currents is influenced by the Coriolis force, the shape of the sea basins and the outlines of the coasts. In general, the circulation of ocean currents is similar to the distribution of air currents over the oceans and occurs clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere.

Crossing the warm currents heading towards the poles, the air becomes warmer and more humid and has a corresponding effect on the climate. Ocean currents heading towards the equator carry cool waters. Passing along the western outskirts of the continents, they lower the temperature and moisture content of the air, and, accordingly, the climate under their influence becomes cooler and drier. Due to the condensation of moisture near the cold surface of the sea, fog often occurs in such areas.

The relief of the earth's surface.

Large landforms have a significant impact on the climate, which varies depending on the height of the terrain and the interaction of air currents with orographic obstacles. The air temperature usually decreases with height, which leads to the formation of a cooler climate in the mountains and on the plateau than in the adjacent lowlands. In addition, hills and mountains form obstacles that force the air to rise and expand. As it expands, it cools. This cooling, called adiabatic, often results in moisture condensation and the formation of clouds and precipitation. Most of the precipitation caused by the barrier effect of mountains falls on their windward side, while the leeward side remains in the "rain shadow". Air descending on leeward slopes heats up as it compresses, creating a warm, dry wind known as a foehn.

CLIMATE AND LATITUDE

In climate surveys of the Earth, it is expedient to consider latitude zones. The distribution of climatic zones in the Northern and Southern hemispheres is symmetrical. Tropical, subtropical, temperate, subpolar and polar zones are located north and south of the equator. Baric fields and zones of prevailing winds are also symmetrical. Consequently, most climate types in one hemisphere can be found at similar latitudes in the other hemisphere.

MAIN CLIMATE TYPES

The classification of climates provides an ordered system for characterizing climate types, their zoning and mapping. Climate types that prevail over vast areas are called macroclimates. A macroclimatic region should have more or less uniform climatic conditions that distinguish it from other regions, although they are only a generalized characteristic (since there are no two places with an identical climate), more in line with realities than the allocation of climatic regions only on the basis of belonging to a certain latitude. - geographic zone.

Ice sheet climate

dominates Greenland and Antarctica, where average monthly temperatures are below 0 ° C. During the dark winter season, these regions do not receive solar radiation at all, although there are twilight and auroras. Even in summer, the sun's rays fall on the earth's surface at a slight angle, which reduces the heating efficiency. Most of the incoming solar radiation is reflected by the ice. In both summer and winter, low temperatures prevail in the elevated regions of the Antarctic Ice Sheet. The climate of the interior of Antarctica is much colder than the climate of the Arctic, because southern mainland is different large sizes and heights, and the Arctic Ocean moderates the climate, despite the wide distribution of pack ice. In summer, during short periods of warming, drift ice sometimes melts.

Precipitation on ice sheets falls in the form of snow or small particles of ice mist. Inland regions receive only 50-125 mm of precipitation annually, but more than 500 mm can fall on the coast. 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, bringing snow to the coast.

subpolar climate

manifests itself in the tundra regions on the northern outskirts North America and Eurasia, as well as on the Antarctic Peninsula and adjacent islands. In eastern Canada and Siberia, the southern boundary of this climatic zone runs well south of the Arctic Circle due to the strongly pronounced 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 filtration melt water into the ground. Therefore, in summer, flat areas turn out to be swampy. On the coast, winter temperatures are somewhat higher, and summer temperatures are somewhat lower than in the interior of the mainland. In summer, when moist air is above cold water or sea ​​ice, fogs often occur on the Arctic coasts.

The annual amount of precipitation usually does not exceed 380 mm. Most of them fall as rain or snow in summer, when cyclones pass. On the coast, the bulk of precipitation can be brought by winter cyclones. But low temperatures and clear weather cold season, characteristic of most areas with a subpolar climate, are unfavorable for significant snow accumulation.

subarctic climate

It is also known under the name "taiga climate" (according to the predominant type of vegetation - coniferous forests). This climate zone covers temperate latitudes. northern hemisphere – northern regions North America and Eurasia, located immediately south of the subpolar climatic zone. There are sharp seasonal climatic differences due to the position of this climatic 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. Summers are short and cool with long days. In winter, the period with negative temperatures is very long, and in summer the temperature can sometimes exceed +32° С. the annual temperature range reaches 62 ° C. A milder climate is typical for coastal areas, such as southern Alaska or northern Scandinavia.

In most of the considered climatic zone, less than 500 mm of precipitation per year falls, and their amount is maximum on the windward coasts and minimum in the interior of Siberia. Very little snow falls in winter, snowfalls are associated with rare cyclones. Summers tend to be wetter, with rainfall mostly during the passage of atmospheric fronts. The coasts are often foggy and overcast. In winter, in severe frosts, icy fogs hang over the snow cover.

Humid continental climate with short summers

characteristic of a vast band of temperate latitudes of the Northern Hemisphere. In North America, it extends from the prairies of south-central Canada to the Atlantic coast, while in Eurasia it covers most of of Eastern Europe and some areas of Central Siberia. The same type of climate is observed in the Japanese island of Hokkaido and in the south of the Far East. The main climatic features of these regions are determined by the prevailing westerly transport and the frequent passage of atmospheric fronts. IN harsh winters average air temperatures can drop to -18°C. Summer is short and cool, frost-free period is less than 150 days. The annual temperature amplitude is not as large as under conditions subarctic climate. In Moscow, the average temperatures in January are -9 ° С, in July - + 18 ° С. In this climatic zone, there is a constant threat to Agriculture represent spring frosts. In the coastal provinces of Canada, in New England and on about. Hokkaido's winters are warmer than inland areas, as easterly winds occasionally bring in warmer ocean air.

Annual rainfall ranges from less than 500 mm in the interior of the continents to over 1000 mm on the coasts. In most of the region, precipitation occurs mainly in summer, often during thunderstorms. Winter precipitation, mainly in the form of snow, is associated with the passage of fronts in cyclones. Blizzards are often observed in the rear of a cold front.

Humid continental climate with long summers.

Air temperatures and the duration of the summer season increase to the south in areas of humid continental climate. This type of climate is manifested in the temperate latitudinal zone of North America from the eastern part of the Great Plains to Atlantic coast, and in southeastern Europe - in the lower reaches of the Danube. Similar climatic conditions are also expressed in northeastern China and central Japan. Here, too, western transport predominates. The average temperature of the warmest month is +22°C (but temperatures can exceed +38°C), summer nights warm. Winters are not as cold as in areas of humid continental climate with short summer, but the temperature sometimes drops below 0 ° C. The annual temperature range is usually 28 ° C, as, for example, in Peoria (Illinois, USA), where the average January temperature is -4 ° C, and July - +24 ° C. On the coast, the annual temperature amplitudes decrease.

Most often, in a humid continental climate with a long summer, from 500 to 1100 mm of precipitation falls annually. The largest number precipitation is brought by summer thunderstorms during the growing season. In winter, rains and snowfalls are mainly associated with the passage of cyclones and related fronts.

Maritime climate of temperate latitudes

inherent in the western coasts of the continents, primarily in northwestern Europe, the central part of the Pacific coast of North America, southern Chile, southeastern Australia and New Zealand. The mode of air temperature is moderated by the prevailing westerly winds blowing from the oceans. Winters are mild, with average temperatures of the coldest month above 0°C, but when the Arctic air currents reach the coasts, there are also frosts. Summers are generally quite warm; during the intrusions of continental air during the day, the temperature can a short time rise to + 38 ° C. This type of climate with a small annual amplitude temperature is the most moderate among climates of temperate latitudes. For example, in Paris, the average temperature in January is + 3 ° C, in July - + 18 ° C.

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. Precipitation is fairly even throughout the year in many areas, with the exception of the US Pacific Northwest, which has very wet winters. Cyclones moving from the oceans bring a lot of precipitation to the western continental margins. In winter, as a rule, cloudy weather persists with light rains and occasional short-term snowfalls. Fogs are common on the coasts, especially in summer and autumn.

Humid subtropical climate

characteristic of the eastern coasts of the continents north and south of the tropics. The main areas of distribution are the southeastern United States, some southeastern regions 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 East Coast Australia. Summer in the humid subtropics is long and hot, with the same temperatures as in the tropics. The average temperature of the warmest month exceeds +27°C, and the maximum is +38°C. Winters are mild, with average monthly temperatures above 0°C, but occasional frosts have a detrimental effect on vegetable and citrus plantations.

In the humid subtropics, the average annual precipitation ranges from 750 to 2000 mm, the distribution of precipitation over the seasons is quite uniform. In winter, rains 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, which are characteristic of the monsoonal circulation of East Asia. Hurricanes (or typhoons) appear in late summer and autumn, especially in the Northern Hemisphere.

Subtropical climate with dry summers

typical of the western coasts of the continents north and south of the tropics. In Southern Europe and North Africa, such climatic conditions are typical for the coasts mediterranean sea, which was the reason to call this climate also Mediterranean. Same climate in southern California central regions Chile, in the extreme south of Africa and in a number of areas in southern Australia. All these regions have hot summers and mild winters. As in the humid subtropics, there are occasional frosts in winter. In inland areas, summer temperatures are much higher than on the coasts, and often the same as in tropical deserts. In general, clear weather prevails. In summer, on the coasts near which ocean currents pass, there are often fogs. For example, in San Francisco, summers are cool, foggy, and most warm month- September.

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. The average annual amount precipitation in a subtropical climate ranges from 380 to 900 mm and reaches maximum values ​​on the coasts and mountain slopes. In the summer, there is usually not enough rainfall for the normal growth of trees, and therefore a specific type of evergreen shrub vegetation develops there, known as maquis, chaparral, mali, machia and fynbosh.

Semi-arid climate of temperate latitudes

(synonym - steppe climate) is characteristic mainly for inland regions, remote from the oceans - sources of moisture - and usually located in the rain shadow of high mountains. The main regions with a semi-arid climate are the intermountain basins and the Great Plains of North America and the steppes of central Eurasia. Hot summers and cold winters are due to the inland position in temperate latitudes. At least one winter month has average temperature below 0°С, and the average temperature of the warmest summer month exceeds +21°С. Temperature regime and the duration of the frost-free period vary significantly with latitude.

The term "semiarid" is used to characterize this climate because it is less dry than the actual arid climate. The average annual precipitation is usually less than 500 mm but more than 250 mm. Since the development of steppe vegetation at higher temperatures requires more precipitation, the latitudinal-geographical and altitudinal position of the area is determined by climatic changes. For semi-arid climate there are no general regularities in the distribution of precipitation throughout the year. For example, areas bordering the subtropics with dry summers experience a maximum of precipitation in winter, while areas adjacent to areas of a humid continental climate experience rainfall mainly in summer. Mid-latitude cyclones bring most of the winter precipitation, which often falls as snow and can be accompanied by strong winds. Summer thunderstorms often come with hail. The amount of precipitation varies greatly from year to year.

Arid climate of temperate latitudes

is inherent mainly in the Central Asian deserts, and in the western United States - only in small areas in intermountain basins. Temperatures are the same as in regions with a semi-arid climate, but the precipitation here is not enough for the existence of a closed natural vegetation cover and the average annual amounts usually do not exceed 250 mm. As in semi-arid climatic conditions, the amount of precipitation that determines aridity depends on the thermal regime.

Semi-arid climate of low latitudes

mostly typical of the fringes of tropical deserts (eg the Sahara and the deserts of central Australia), where downdrafts in subtropical high pressure zones preclude precipitation. The climate under consideration differs from the semi-arid climate of temperate latitudes by 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 dense natural herbaceous vegetation is higher here than in temperate latitudes. In the equatorial zone, it rains mainly in summer, while on the outer (northern and southern) margins of the deserts, the maximum precipitation occurs in winter. Precipitation for the most part falls in the form of thunderstorms, and in winter the rains are brought by cyclones.

Arid climate of low latitudes.

This is a hot dry climate of tropical deserts, stretching along the Northern and Southern tropics and being influenced by subtropical anticyclones for most of the year. Salvation from the sweltering summer heat can only be found on the coasts washed by cold ocean currents, or in the mountains. On the plains, the average summer temperatures noticeably exceed + 32 ° C, winter ones 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 for several years in a row precipitation is not recorded at all. Sometimes the average annual precipitation can reach 380 mm, but this is still enough only for the development of sparse desert vegetation. Occasionally, precipitation occurs in the form of short-lived heavy thunderstorms, but the water quickly drains to form flash floods. The driest regions are along the western coasts of South America and Africa, where cold ocean currents prevent cloud formation and precipitation. These coasts often have fogs formed by the condensation of moisture in the air over the colder surface of the ocean.

Variable humid tropical climate.

Areas with such a climate are located in tropical sublatitudinal zones, a few degrees north and south of the equator. This climate is also called monsoonal tropical, as it prevails in those parts of South Asia that are influenced by monsoons. Other areas with such a climate are the tropics of Central and South America, Africa and northern Australia. Average summer temperatures are usually approx. + 27 ° С, and winter - approx. + 21 ° C. The hottest month usually precedes summer season rain.

Average annual rainfall ranges from 750 to 2000 mm. During the summer rainy season the intertropical convergence zone exerts a decisive influence on the climate. There are often thunderstorms here, sometimes continuous cloud cover with prolonged 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 indian ocean, and in winter, Asian continental dry air masses spread here.

humid tropical climate,

or the climate of tropical rainforests, common in equatorial latitudes in the Amazon basin in South America and the Congo in Africa, on the Malay Peninsula and on the islands of Southeast Asia. In the humid tropics, the average temperature of any month is not less than + 17 ° C, usually the average monthly temperature is approx. + 26 ° C. As in the variable humid tropics, due to the high midday position of the Sun above the horizon and the same length of the day throughout the year, seasonal temperature fluctuations are small. Moist air, cloudiness and dense vegetation prevent night cooling and maintain maximum daytime temperatures below +37°C, lower than at higher latitudes.

The average annual rainfall in the humid tropics ranges from 1500 to 2500 mm, the distribution over the seasons is usually fairly even. Precipitation is mainly associated with the intratropical 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 precipitation maxima during the year, separated by drier periods. Every day, thousands of thunderstorms roll over the humid tropics. In the intervals between them, the sun shines in full force.

Highland climates.

In high-mountainous regions, a significant variety of climatic conditions is due to the latitudinal-geographical position, orographic barriers, and different exposure of the slopes in relation to the Sun and moisture-bearing air currents. Even at the equator in the mountains there are snowfields-migrations. The lower boundary of the eternal snows 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. Windward slopes of mountain ranges receive more precipitation. On mountain slopes open to the intrusions of cold air, a drop in temperature is possible. 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. The nature of seasonal changes in temperature and precipitation in the highlands is usually the same as in the adjacent plains.

MESO AND MICROCLIMATES

Territories that are inferior in size to macroclimatic regions also have climatic features that deserve special study and classification. Mesoclimates (from the Greek. meso - medium) are the climates of territories several square kilometers in size, for example, wide river valleys, intermountain depressions, basins big lakes or cities. In terms of distribution area and nature of differences, mesoclimates are intermediate between macroclimates and microclimates. The latter characterize the climatic conditions in small areas of the earth's surface. Microclimatic observations are carried out, for example, on the streets of cities or on test sites established within a homogeneous plant community.

EXTREME CLIMATE INDICATORS

Such climatic characteristics, like temperature and precipitation, vary over a wide range between extreme (minimum and maximum) values. Although they are rarely observed, extremes are just as important as averages in understanding the nature of the climate. The climate of the tropics is the warmest, with the climate of tropical rainforests being hot and humid, and the arid climate of low latitudes being hot and dry. Maximum temperatures air are noted in tropical deserts. The highest temperature in the world - +57.8 ° C - was recorded in El-Azizia (Libya) on September 13, 1922, and the lowest - -89.2 ° C at the Soviet Vostok station in Antarctica on July 21, 1983.

Rainfall extremes have been recorded in different parts of the world. For example, for 12 months from August 1860 to July 1861, 26,461 mm fell in the town of Cherrapunji (India). The average annual rainfall in this point, one of the rainiest on the planet, is approx. 12,000 mm. Less data are available on the amount of snowfall. At Paradise Ranger Station in Mount Rainier National Park (Washington, USA), 28,500 mm of snow was recorded during the winter of 1971-1972. At many meteorological stations in the tropics with long series of observations, precipitation has never been recorded at all. There are many such places in the Sahara and on the west coast of South America.

At extreme wind speeds, measuring instruments (anemometers, anemographs, etc.) often failed. The highest wind speeds in the surface air probably develop in tornadoes, where it is estimated that they can be much higher than 800 km/h. In hurricanes or typhoons, winds sometimes reach speeds of over 320 km/h. Hurricanes are very typical of the Caribbean and Western Pacific Ocean.

IMPACT OF CLIMATE ON BIOTA

The temperature and light regimes and moisture supply necessary for the development of plants and limiting their geographical distribution depend on the climate. Most plants cannot grow at temperatures below +5°C, and many species die at sub-zero temperatures. As temperatures increase, the moisture requirements of plants increase. Light is essential for photosynthesis, as well as for flowering and seed development. Shading the soil with tree crowns in a dense forest inhibits the growth of more low plants. An important factor is also the wind, which significantly changes the regime of temperature and humidity.

The vegetation of each region is an indicator of its climate, since the distribution of plant communities is largely driven by climate. The vegetation of the tundra in a subpolar climate is formed only by such undersized forms as lichens, mosses, grasses and low shrubs. Short growing season and wide distribution permafrost make it difficult for trees to grow everywhere, except for river valleys and south-facing slopes, where the soil thaws to a greater depth in summer. Coniferous forests of spruce, fir, pine and larch, also called taiga, grow in a subarctic climate.

Humid regions of temperate and low latitudes are especially favorable for forest growth. The densest forests are confined to areas of temperate maritime climate and humid tropics. Areas of humid continental and humid subtropical climate are also mostly forested. In the presence of a dry season, such as in areas of subtropical climate with dry summers or variable humid tropical climates, plants adapt accordingly, forming either a stunted or sparse tree layer. Thus, in the savannas, under conditions of a variable-humid tropical climate, grasslands with single trees growing at great distances from one another predominate.

In semi-arid climates of temperate and low latitudes, where everywhere (except for river valleys) it is too dry for tree growth, herbaceous steppe vegetation dominates. The grasses here are stunted, and an admixture of semi-shrubs and semi-shrubs is also possible, for example, wormwood in North America. In temperate latitudes, grass steppes in more humid conditions at the borders of their range are replaced by tall grass prairies. In arid conditions, plants grow far apart, often have thick bark or fleshy stems and leaves that can store moisture. The driest regions of tropical deserts are completely devoid of vegetation and are exposed rocky or sandy surfaces.

The climatic altitudinal zonality in the mountains determines the corresponding vertical differentiation of vegetation - from grassy communities of foothill plains to forests and alpine meadows.

Many animals are able to adapt to a wide range of climatic conditions. For example, mammals in cold climates or in winter have warmer fur. However, the availability of food and water is also important for them, which varies depending on the climate and season. Many species of animals are characterized by seasonal migrations from one climatic region to another. For example, in winter, when grasses and shrubs dry up in the variable humid tropical climate of Africa, mass migrations of herbivores and predators to more humid areas occur.

In the natural zones of the globe, soils, vegetation and climate are closely interrelated. Heat and moisture determine the nature and rate of chemical, physical and biological processes, resulting in changes rocks on the slopes of different steepness and exposure and creates a huge variety of soils. Where the soil is bound by permafrost for most of the year, as in the tundra or high in the mountains, soil formation processes are slowed down. In arid conditions, soluble salts are usually found on the soil surface or in near-surface horizons. In humid climates excess moisture seeps down, carrying soluble mineral compounds and clay particles to considerable depths. Some of the most fertile soils are products of recent accumulation - wind, fluvial or volcanic. Such young soils have not yet undergone strong leaching and therefore retained nutrient reserves.

Crop distribution and soil cultivation practices are closely related to climatic conditions. Bananas and rubber trees require an abundance of warmth and moisture. Date palms grow well only in oases in arid low-latitude areas. For most crops in arid conditions of temperate and low latitudes, irrigation is necessary. The usual type of land use in areas of semi-arid climate, where grasslands are common, is grazing. Cotton and rice have a longer growing season than spring wheat or potatoes, and all of these crops suffer from frost. In the mountains, agricultural production is differentiated by altitudinal zones in the same way as natural vegetation. Deep valleys in the humid tropics Latin America are located in the hot zone (tierra caliente) and tropical crops are grown there. At several higher altitudes temperate zone(tierra templada) coffee is a typical crop. Above is the cold zone (tierra fria), where cereals and potatoes are grown. In an even colder belt (tierra helada), located just below the snow line, alpine meadows are grazing, and crops are extremely limited.

The climate affects the health and living conditions of people as well as their economic activities. The human body loses heat through radiation, conduction, convection and evaporation of moisture from the surface of the body. If these losses are too great in cold weather or too small in hot weather, a person experiences discomfort and can get sick. Low relative humidity and high speed winds enhance the cooling effect. Weather changes lead to stress, impair appetite, disrupt biorhythms and reduce the resistance of the human body to disease. The climate also affects the living conditions pathogenic microorganisms that cause disease, and therefore seasonal and regional outbreaks occur. Epidemics of pneumonia and influenza in temperate latitudes often occur in winter. Malaria is common in the tropics and subtropics, where there are conditions for the reproduction of malarial mosquitoes. Diseases caused by malnutrition are indirectly related to climate, since in food products produced in a particular region, as a result of the influence of climate on plant growth and soil composition, some nutrients may be lacking.

CLIMATE CHANGE

Rocks, plant fossils, landforms, and glacial deposits contain information about significant fluctuations in average temperatures and precipitation over geological time. Climate change can also be studied by analyzing tree rings, alluvial deposits, ocean and lake bottom sediments, and organic peatland deposits. Over the past few million years there has been a general cooling of the climate, and now, judging by the continuous reduction of the polar ice sheets, we seem to be at the end of the ice age.

Climate change over historical period can sometimes be reconstructed from information about famines, floods, abandoned settlements, and migrations of peoples. Continuous series of air temperature measurements are only available for meteorological stations located predominantly in the Northern Hemisphere. They cover only a little over one century. These data indicate that over the past 100 years, the average temperature in the globe increased by almost 0.5 ° C. This change did not occur smoothly, but abruptly - sharp warming followed by relatively stable stages.

Experts from various fields of knowledge have proposed numerous hypotheses to explain the causes of climate change. Some believe that climatic cycles are determined by periodic fluctuations in solar activity with an interval of approx. 11 years. Annual and seasonal temperatures could be influenced by changes in the shape of the Earth's orbit, which led to a change in the distance between the Sun and the Earth. The Earth is currently closest to the Sun in January, but approximately 10,500 years ago it was in this position in July. According to another hypothesis, depending on the angle of inclination of the earth's axis, the amount of solar radiation entering the Earth changed, which affected the general circulation of the atmosphere. It is also possible that the polar axis of the Earth occupied a different position. If the geographic poles were at the latitude of the modern equator, then, accordingly, the climatic zones also shifted.

The so-called geographic theories explain long-term climate fluctuations by movements of the earth's crust and changes in the position of continents and oceans. In the light of global plate tectonics, continents have moved over geological time. As a result, their position in relation to the oceans, as well as in latitude, changed. In the process of mountain building, mountain systems with a cooler and, possibly, more humid climate were formed.

Air pollution also contributes to climate change. Large masses of dust and gases released into the atmosphere during volcanic eruptions occasionally became an obstacle to solar radiation and led to cooling of the earth's surface. An increase in the concentration of certain gases in the atmosphere exacerbates the overall warming trend.

The greenhouse effect.

Like the glass roof of a greenhouse, many gases pass most of the thermal and light energy of the Sun to the Earth's surface, but prevent the rapid return of the heat radiated by it to the surrounding space. The main gases causing the "greenhouse" effect are water vapor and carbon dioxide, as well as methane, fluorocarbons and nitrogen oxides. Without greenhouse effect the temperature of the earth's surface would drop so much that the entire planet would be covered with ice. However, an excessive increase in the greenhouse effect can also be catastrophic.

Since the beginning of the industrial revolution, the amount of greenhouse gases (mainly carbon dioxide) in the atmosphere has increased due to human activities and especially the burning of fossil fuels. Many scientists now believe that the rise in global mean temperature since 1850 was mainly due to increases in atmospheric carbon dioxide and other anthropogenic greenhouse gases. If modern tendencies use of fossil fuels will continue into the 21st century, the average global temperature could rise by 2.5–8°C by 2075. If fossil fuels are used at a faster rate than at present, such an increase in temperature could occur as early as 2030.

Projected rise in temperature could lead to melting polar ice and most mountain glaciers, causing sea levels to rise by 30 to 120 cm. All of this could also affect changes in the Earth's weather patterns, with possible consequences such as prolonged droughts in the world's leading agricultural regions.

but global warming as a consequence of the greenhouse effect can be slowed down if carbon dioxide emissions from burning fossil fuels are reduced. Such a reduction would require restrictions on its use throughout the world, more efficient energy consumption and an increase in the use of alternative energy sources (for example, water, solar, wind, hydrogen, etc.).

Literature:

Pogosyan Kh.P. General circulation atmosphere. L., 1952
Blutgen I. Geography of climates, vol. 1–2. M., 1972–1973
Vitvitsky G.N. Zonality of the Earth's climate. M., 1980
Yasamanov N.A. Earth's ancient climates. L., 1985
Climate fluctuations over the last millennium. L., 1988
Khromov S.P., Petrosyants M.A. Meteorology and climatology. M., 1994



Areas with a maritime climate on Earth according to the Köppen classification

maritime climate (oceanic climate) - the climate of regions close to the sea, characterized by small daily and annual air temperature amplitudes, high humidity, cool summers and mild winters (in temperate latitudes), large clouds caused by intense cyclonic activity, strong winds. In a maritime climate, the onset of high and low temperatures is delayed (compared to areas with a continental climate) by 1-2 months, and spring is colder than autumn. It is formed under the prevailing influence of oceanic spaces on the atmosphere.

A similar climate, at least in the temperature range, also exists in the tropical highlands, even at a considerable distance from either coast. As a rule, by climate classification Köppen it is classified as CFB or Cwb (oceanic climate). Small fluctuations in temperature are not the result of proximity to the coastline, small fluctuations in temperatures between seasons also characterize the tropical lowlands; but the highlands are high enough above sea level that one month of the year has an average temperature below 18 C and cannot be classified as a true tropical climate. Unlike actual oceanic climates, these places with humid highland tropical climates can have noticeable winter droughts, as in Mexico City. As in the case of an oceanic climate, winters are relatively warm and summers are relatively cool, so the agricultural potential in an oceanic climate and a humid tropical highland climate is almost identical. The oceanic climate is most prevalent in Europe, where it extends much farther than on other continents.

1. Precipitation

Precipitation occurs consistently in areas with an oceanic climate, with the exception of some tropical mountainous areas, which should be classified as tropical shroud or semi-desert climates (through the dry season in winter), but have low temperatures through the altitudinal position (Koppen classification). cwb). According to some provisions of the Koppen classification system, part of the Pacific Northwest and south-central Chile are sometimes considered a type of Mediterranean climate (Köppen classification csb) through summer droughts.

2. Temperature

There are very large temperature variations in areas with an oceanic climate; in low latitudes, the climate is almost subtropical in terms of temperature, but the average temperature differs - cool, but not cold, winters and warm, but not hot, summers. The average temperature in the warmest month should not exceed 22 C, and in the cold month should be higher than -3 C (Although American scientists interpret 0 C in a cold month). Weather in the zone of the subpolar oceanic climate (according to the Köppen classification cfc), has long but relatively mild winters (cold month is warmer than -3 C or 0 C) and short and cool summers (average temperature not lower than 10 C), and for four months climate examples are the coastal regions of Iceland in the Northern Hemisphere and the extreme south of Chile in the southern hemisphere.

3. Additional information

Great Britain has a maritime climate, dominated by southwesterly winds from the Atlantic Ocean. The average annual temperature variation in the UK is only about 24 C. Although the west coast of Alaska has a maritime climate, the lack of a similarly strong warm Pacific current in the upper mid-latitudes has meant that the region has an overall more cold winter, and has more precipitation in the form of snow. Another example is the coastal regions of southeastern Western Australia.

4. Countries and regions with a temperate maritime climate

• Northern and Western France
• Western and northwestern Germany
• Western Switzerland (low-lying areas)
• Northern Spain (so-called "Green Spain")
• Far North of Portugal
• Southwestern Norway
• Part of Denmark
• Northern Turkey
• Tasmania, (Australia)
• Southern Victoria and New South Wales, (Australia)
• Western areas on the south coast of Western Australia
• Central Argentina
• Southern Chile
• Western Oregon, Washington, and middle coast of Alaska (USA)
• Northwest Territory of California (USA)
• Western British Columbia (Canada)
• Highlands in some tropical countries (for example, the highlands of the Indian subcontinent, Latin America, southern and central Africa, according to the Köppen classification cwb)
• Part of South and Southeast South Africa
• Some mountainous areas throughout southern Europe
• Parts of the Himalayas

The regions, in winter, have an average temperature between -3 C and 0 C, in all other respects have a maritime climate.

The temperate climate zone is present on all continents of the earth, except for Antarctica. In the Southern and Northern Hemispheres, they have some features. Generally temperate climate is present on 25% of the earth's surface. The distinctive feature of this climate is that all seasons are inherent in it, and four seasons are clearly traced. The main ones are hot summers and frosty winters, transitional ones are spring and autumn.

change of seasons

In winter, the air temperature drops well below zero degrees, on average -20 degrees Celsius, and the minimum drops to -50. Precipitation falls in the form of snow and covers the ground in a thick layer that different countries lasts from several weeks to several months. There are many cyclones.

Summer in a temperate climate is quite hot - the temperature is more than +20 degrees Celsius, and in some places even +35 degrees. The average annual rainfall in different regions varies from 500 to 2000 millimeters, depending on the distance from the seas and oceans. Quite a lot of rain falls in the summer, sometimes up to 750 mm per season. In transitional seasons, minus and plus temperatures can last for different times. Some areas are warmer, while others are cooler. In some regions, autumn is quite rainy.

In the temperate climate zone during the year there is an exchange of thermal energy with other latitudes. Water vapor is also transferred from the oceans to land. There are a fairly large number of reservoirs inside the mainland.

Temperate subtypes

Due to the influence of some climatic factors, the following subspecies of the temperate zone were formed:

• sea ​​- summer is not very hot with big amount rainfall, and mild winters;
• monsoon - the weather regime depends on the circulation of air masses, namely monsoons;
• transitional from maritime to continental;
• sharply continental - winters are harsh and cold, and summers are short and not very hot.

Features of a temperate climate

In a temperate climate, various natural areas, but most often it is, as well as broad-leaved, mixed. Sometimes there is a steppe. The animal world is represented, respectively, by individuals for forests and steppes.

Thus, the temperate climate covers most of Eurasia and North America, in Australia, Africa and South America it is represented by several centers. This is a very special climatic zone, characterized by the fact that all seasons are pronounced in it.

The climate within the Earth's surface varies zonal. The most modern classification, which explains the reasons for the formation of a particular type of climate, was developed by B.P. Alisov. It is based on the types of air masses and their movement.

air masses- These are significant volumes of air with certain properties, the main of which are temperature and moisture content. The properties of air masses are determined by the properties of the surface over which they form. Air masses form the troposphere like the lithospheric plates that make up the earth's crust.

Depending on the region of formation, four main types of air masses are distinguished: equatorial, tropical, temperate (polar) and arctic (antarctic). In addition to the area of ​​formation, the nature of the surface (land or sea) over which air accumulates is also important. In accordance with this, the main zonal types of air masses are divided into maritime and continental.

Arctic air masses are formed in high latitudes, above the ice surface of the polar countries. Arctic air is characterized by low temperatures and low moisture content.

moderate air masses clearly divided into marine and continental. Continental temperate air is characterized by low moisture content, high summer and low winter temperatures. Maritime temperate air forms over the oceans. It is cool in summer, moderately cold in winter and constantly wet.

Continental tropical air formed over tropical deserts. It is hot and dry. Sea air is characterized by lower temperatures and much higher humidity.

equatorial air, forming a zone at the equator both over the sea and over land, has high temperature and humidity.

Air masses constantly move after the sun: in June - to the north, in January - to the south. As a result, territories are formed on the surface of the earth where one type of air mass dominates during the year and where air masses replace each other according to the seasons of the year.

The main feature of the climate zone is the dominance of certain types of air masses. subdivided into main(during the year, one zonal type of air masses dominates) and transitional(air masses change seasonally). The main climatic zones are designated in accordance with the names of the main zonal types of air masses. At transitional belts the prefix "sub" is added to the name of the air masses.

Main climatic zones: equatorial, tropical, temperate, arctic (antarctic); transitional: subequatorial, subtropical, subarctic.

All climatic zones, except for the equatorial one, are paired, that is, there are both in the Northern and Southern hemispheres.

In the equatorial climate zone all year round equatorial air masses dominate, low pressure prevails. It is humid and hot throughout the year. The seasons of the year are not expressed.

Tropical air masses (hot and dry) dominate throughout the year. tropical zones. Due to the downward movement of air that prevails throughout the year, very little precipitation falls. Summer temperatures are higher here than in equatorial belt. Winds are trade winds.

For temperate zones characterized by the dominance of moderate air masses throughout the year. Westerly air transport prevails. Temperatures are positive in summer and negative in winter. Due to the predominance of low pressure, a lot of precipitation falls, especially on ocean coasts. In winter, precipitation falls in solid form (snow, hail).

In the Arctic (Antarctic) belt Cold and dry arctic air masses dominate throughout the year. It is characterized by downward movement of air, north- and south-east winds, the predominance of negative temperatures throughout the year, and constant snow cover.

IN subequatorial belt there is a seasonal change of air masses, the seasons of the year are expressed. Summer is hot and humid due to the arrival of equatorial air masses. In winter, tropical air masses dominate, so it is warm but dry.

In the subtropical zone moderate (summer) and arctic (winter) air masses change. Winter is not only severe, but also dry. Summers are much warmer than winters, with more rainfall.

Climatic regions are distinguished within the climatic zones from different types climates - maritime, continental, monsoon. Marine type of climate formed under the influence of sea air masses. It is characterized by a small amplitude of air temperature for the seasons of the year, high cloudiness, and a relatively large amount of precipitation. Continental type of climate formed away from the ocean coast. It is distinguished by a significant annual amplitude of air temperatures, a small amount of precipitation, and a distinct expression of the seasons of the year. Monsoon type of climate It is characterized by the change of winds according to the seasons of the year. At the same time, the wind changes direction with the change of season, which affects the precipitation regime. Rainy summers give way to dry winters.

Largest number climatic regions available within the temperate and subtropical zones of the Northern Hemisphere.

Do you have any questions? Want to know more about climate?
To get the help of a tutor - register.
The first lesson is free!

site, with full or partial copying of the material, a link to the source is required.