Climate

The geographical position determines the domination of temperate climate in E., and the presence of western air transport from the Atlantic Ocean above it leads to the predominance of marine and transitional from marine to continental types of climate. The average annual values ​​of the radiation balance are everywhere positive and increase from north to south: on the islands of the Arctic they are about 10, near the 50th parallel about 40, in the southern regions of E. up to 250-290 kJ / cm2 (60-70 kcal / cm2). In January, all E., except the Mediterranean and most of France, has a radiation balance of –17 to –4.2 kJ / cm2 (from –4 to –1 kcal / cm2); in July, the differences between the northern and southern regions are erased due to an increase in the length of the day when moving to the north, and the radiation balance over almost all of E. is about 34 kJ / cm2 (8 kcal / cm2). The movement of air masses in the system of general circulation of the atmosphere leads to a significant territorial redistribution of heat, especially in winter. The warming role of the western transport, reinforced by the presence of a warm North Atlantic current, is manifested in the deviation of the isotherms of the winter months from the latitudinal direction and in a significant excess of the average temperatures of the winter months in most of E. (except for the south-east) over average latitudinal temperatures: a positive anomaly January temperatures on Novaya Zemlya, the Kola Peninsula, Svalbard, the British Isles ranges from 8 to 18 ° C, and in the west of Scandinavia and Iceland from 18 to 24 ° C.

Radiation and circulation factors of climate formation E. have a pronounced seasonal change. In the winter season, the lowest atmospheric pressure occurs in the north of the Atlantic, where the Icelandic depression is located. Hence, the pressure increases to the east and southeast. right up to the Caspian Sea and the south of the Urals, where the spur of the Asian anticyclone enters. Over the western part of the Mediterranean Sea, located in the zone of influence of the Azores anticyclone, western transport is very intense. In his system, cyclones arising at atmospheric fronts move from the west to the east, deviating to higher latitudes. Almost all of E. polar air masses prevail; breakthroughs of Arctic air masses from the north can reach the Alps, the Balkan Peninsula and the Crimea; in the Mediterranean, polar air is sometimes replaced by tropical air. Isotherms of the winter months pass in general with S.-Z. to the south-east The highest average monthly temperatures in January are in the Mediterranean, from 10 to 12 ° C, as well as in the near-ocean regions of E., where the 0 ° C isotherm reaches 70 ° C. w. The lowest average monthly temperatures are in the north-eastern regions of E., up to –20 ° С in the river basin. Pechora (here the absolute minimum temperature was recorded in E. —52 ° C) and up to –24 ° C on Franz Josef Land. In general, winters are mild in West E., frosty in Eastern E., with stable snow cover, lasting from 1 month in the south to 7–9 months in the north.

In the summer season, pressure gradients decrease. In July, in the region of Iceland and over most of Eastern E., pressure remains low. The greatest pressure is in the area of ​​the Azores anticyclone, the influence of which extends to the entire Mediterranean and partly to Middle E. The intensity of cyclonic activity is reduced in comparison with winter. In the Mediterranean, tropical air dominates, over the Arctic — arctic, over the rest of the regions — polar. Sea air coming from the Atlantic has a lower temperature than continental. On the whole, the near-oceanic territory is somewhat cooler in summer than inland within the same latitudes. Although the isotherms of July are directed approximately in latitude, when approaching the Atlantic Ocean they deviate toward the south, and in the east toward C. The average July temperature reaches its highest values ​​in the Mediterranean, from 28 to 30 ° C, in the Caspian region, from 24 to 26 ° С, the lowest — on the islands of the Arctic, from 2 to 4 ° С. The absolute maximum temperature is 48 ° C (south of the Iberian Peninsula).

The total annual precipitation generally decreases from the west to the east. In the Atlantic regions and on the windward slopes of the mountains, it amounts to 1000–2000 mm (at individual stations in the coastal regions of Yugoslavia it exceeds 4000 mm). In East E., especially in the southeast. and South, the amount of precipitation decreases to 500-300 mm per year, and in the Caspian Sea to 200 mm or less, 300-400 mm falls on most of the islands of the Arctic and on the southern coast of the Barents Sea. In the annual course of precipitation in the Mediterranean and on the southern coast of Crimea, distinct maxima are revealed in the winter half of the year and minima in the summer. In the Atlantic regions of Middle and North E. precipitation is distributed fairly evenly throughout the seasons, but still has a certain maximum in winter: in the inland regions, maximum rainfall occurs in the summer. For most of E. the annual amount of precipitation exceeds the annual value of evaporation, therefore, moistening is sufficient or excessive. In the southern and southeastern regions of Eastern E., as well as in some intermountain depressions of Western E., precipitation does not compensate for annual evaporation, insufficient moisture is created. In the Mediterranean, an acute lack of moisture occurs in the summer. In these areas, almost everywhere there is a need for artificial irrigation.

In E., climate types of the Arctic, subarctic, temperate, and subtropical zones are represented. In the Arctic zone, covering the islands of the European sector of the Arctic, the climate is harsh, with long frosty winters, frequent storms, snowstorms, short cold summers (average July temperature, as a rule, not higher than 5 ° С); Precipitation falls mainly in the form of snow, evaporation is low. In the subarctic zone (Iceland, S. Fennoscandia and the East European Plain), summers are longer and warmer (up to 10, 12 ° С in July), winters are mild in western regions, and frosty in eastern regions; precipitation is about 1000 mm in the west, 400 mm in the east: evaporation is less than precipitation. In the temperate zone (the rest of E., except the Mediterranean and the southern coast of Crimea), the colder, boreal climate of the northern part of the belt and warmer, subboreal — in the southern part are distinguished. In addition, in the western part of the belt, the climate is marine, with a small annual temperature amplitude, warm in the south and cool in the north in summer, mild winters without stable snow cover on the plains, heavy rainfall during all seasons, especially in winter, with sufficient and excessive moisture. In the east, the climate is temperate continental, with frosty snowy winters (except for the southern regions), cool in the north, warm in the center and hot in the south in summer, and a large annual temperature amplitude; annual precipitation is more than evaporation in the north, almost equal to it in the center and less than evaporation in the south. The subtropical zone represents the Mediterranean type of climate with mild, warm but rainy winters (January temperature from 4 to 12 ° C) with variable weather, arid in hot or (in the west) warm summer. In the west of Pyrenees, in the Apennines, in the west and northwest The Balkan Peninsula is represented by a marine variety of this climate (a shortened period of summer dryness, a large amount of rainfall), in the remaining regions of these peninsulas and on the southern coast of Crimea — a continental variety. (See maps)

Climatic indicators

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