If us interests, whether there will be a weather in a resort zone during the certain period of time dry and hot, we speak about a climate - the standard weather conditions of the given district defined on the basis of long-term supervision.
The Primary factors defining a climate, seasonal fluctuations of temperature and deposits (a rain, snow, sleet and a hailstones) are. For example, for the Mediterranean climate which zone covers not only the countries of the Mediterranean, but also a part of territory of California, Chile, Southern Africa and Australia, the soft, rainy winter and dry, hot summer are characteristic. It does not mean that in the summer there there is no rain. Thunder-storms bursting sometimes in the middle of summer bear with themselves downpours. But as a whole it is possible to count on clear, hot weather during bolshej parts of summer.
The district Climate depends on its geographical width, a relief and height above sea level, and also affinity to the sea.
Width and a relief
The Width defines quantity of the solar heat received by given district. The further from equator, the less heat it is absorbed by an earth surface.
The district Height above sea level influences also temperature. As a whole, the temperature decreases on the average on 7 °s each 1000 m of lifting above sea level. Therefore in high-mountainous areas of tropics is much colder, than at the sea coasts which are at the same width, and at tops of high mountains the cold polar climate reigns.
Mountains also influence loss of rains. Rising over a mountain ridge, damp oceanic winds promote formation of clouds, and on slopes plentiful deposits drop out. Through a crest they pass already dry.
The Climate of seaside areas is usually softer, than in the heart of a land. For example, the climate is influenced by coastal and sea breezes. The terrestrial surface heats up faster, than the sea. In the afternoon warm air rises upwards, and its place occupies colder air arriving from the sea. At night there is a return process. As the sea cools down more slowly, than the earth, breezes blow from a land on the sea.
The temperature is influenced by oceanic currents. Warm Gulf Stream crosses on a diagonal Atlantic ocean from Gulf of Mexico to northwest coast of Europe. The sea winds blowing along Gulf Stream in a direction of coast, provide in this part of Europe much softer climate, than at the coast of the North America located at the same width. Cold currents also influence a climate. For example, the Bengelsky current at southwest coast of Africa and Peruvian (or Humboldt) at the western coast of the South America cool tropical regions, differently there would be still zharche.
In the center of continents, far from softening influence of the sea, the severe continental climate with hot summer and is observed in the cold winter.
The Majority of classifications of a climate follows from works of Russian meteorologist Vladimir Keppena (1846-1940). Keppen has divided the world into six basic climatic zones: And, In, With, D, E and N. And - a damp tropical climate, In - dry, With - warm moderated, D - cold moderated, E - polar and N high-mountainous.
Further Keppen has broken climates And, In, With, D and E into subgroups taking into account seasonal fluctuations of temperature and intensity of deposits. Defining borders of climatic zones, it has taken into consideration distribution of natural vegetation and soils. These signs often are more exact indicators, than statistics of environmental conditions. Tropical areas concern a zone And on Keppenu with all-the-year-round rains, and also areas with a damp tropical climate and the droughty period.
Zones with a damp tropical climate
In zones of such climate where monthly there are rains, violent rainforests grow. They occupy the greatest areas in pools of the rivers Amazons (South America) and Zaire (the south of Africa), covering also a considerable part of South East Asia.
For these areas are characteristic a heat all year long (nearby 25-27°С), plentiful deposits (on the average 1800-2500 mm a year), high humidity and the scorching sun. At midday the sun costs almost in zenith, and duration of light day slightly changes within a year. Such conditions are ideal for growth of rainforests.
In zones of a monsoonal climate the majority of rains drops out during the certain period. Such climate meets in some tropical areas, including the south and the southeast of Asia, and also northern part of Australia. These areas are subject to sharp climatic changes throughout a year. In India known for the monsoonal climate there is a dry weather in the winter, and winds from depth of the Asian continent blow. In the spring the earth heats up, weather dry, ached much. Rising, hot air forms extensive area of low pressure (cyclone), drawing damp winds from the southwest. They bring the downpours necessary for local woods. With rainforests grassy plains border on rare trees - savannas for which the dry winter also is characteristic. They occupy the big spaces in tropical Africa and the South America. In the African savannas the climate becomes more and more dry in process of removal from the center to the south or the north. Grasses have grown are replaced by dry prickly young growth and bushes, as in sahele in the North Africa. Destruction of vegetation and strong droughts have transformed the most part sahelja into semi-desert and desert.
Hot tropical deserts concern zones with an arid climate, including Sahara, Namib and Kalahari in Africa. Annually in deserts than 25 mm of deposits drop out less. Years of a drought can suddenly be replaced zataplivajushchimi desert by downpours. Air temperature high with the big differences within days.
The Semidroughty climate, or a climate of steppes, is characteristic for prairies of the North America, steppes of Eurasia, and also velda Southern Africa. These grassy plains (where much more chilly, than in savanna, and winters often cold and snow) have strongly changed as a result of activity of the person. The big territories are occupied under ranch and agricultural farms.
Zones of a warm temperate climate
concern temperate climate zones areas with hot and dry summer (the Mediterranean climate), damp subtropics with warm summer (southeast China, the southeast USA and a pampas of the South America), and also coastal areas with cold summer (the West of the Central Europe). The monthly average temperature in the Mediterranean areas seldom exceeds 27 °s though have been registered and more heats. The winter here is colder. In the coldest months the temperature falls to a mark-10 °s. An annual amount of precipitation small - from 350 to 900 mm. Rains mostly go in the winter. The flora basically is presented by bushes, and also olive and to it the similar trees, capable to transfer a summer drought.
In damp subtropics the same temperature, as in zones of the Mediterranean climate, but here in a year drops out more deposits, basically because of influence of unstable tropical air weights. Humidity high, and in summer days costs heat. Winters, as a rule, soft, with rare frosty days except for east part of China where the cold winds blowing from depth of continent, cause sharp decrease in temperature.
Zones of a cold temperate climate meet at the western coasts of continents at average widths. Here concern the Western Europe, including British isles, the western coast of Canada, the south of Chile and New Zealand.
The Average temperature in the warmest season makes 15-20°С though it often happens above far from coast where not so softening influence of the sea affects. Winter temperature unusually high in comparison with the areas which are at the same widths, but it is far from the sea. Monthly average temperatures here usually above zero. But sometimes cold polar or continental air causes temperature decrease, and some weeks cost snow weather. The big difference in an amount of precipitation is observed: in coastal mountains a lot of moisture, while in flat east part often drops out much more chilly.
The western part of Russia concerns zones of a cold temperate climate with warm summer and in the cold winter. In other areas, including Siberia and the most part of Canada, the subarctic climate with short both cold summer and is observed in very cold winter. The bezmoroznyj period in these parts lasts no more than 150 days. The taiga - huge coniferous woods - occupies the most part of this subarctic area. Coniferous trees (a fir, a larch, a pine and a fur-tree) have learnt to survive in the conditions of long and severe winter. In southern hemisphere there are no such coniferous woods because there there are no big sites of a land at corresponding widths.
Zones of a polar climate
To the north from a strip of coniferous woods of Northern hemisphere the deserted tundra where the average temperature makes nearby-5°S in the winter lies, and during the short summer period rises to +5°С. The Total of deposits, mainly in the form of snow, does not exceed 350 mm a year.
After snow thawing for all period of short summer the tundra turns to the marshland teeming with insects which involve set of birds of passage. The summer vegetation also gives food to migrating animals, such as karibu.
The coldest places on the Earth - polar caps and glacial boards round poles. In the summer the thermometer column usually does not rise above +5 °s, and in the winter monthly average temperatures happen less-50°S. Few deposits as in cold air a lot of moisture cannot contain Here drop out. But during a snow storm the violent wind drives on ice friable snow with a speed more than 160 km/hour.
High mountains represent different climatic zones depending on height above sea level. An ascension on mountain around equator like travel from equator to poles: it is necessary to pass through a number of high-rise climatic zones - from a zone of a damp tropical climate at bottom of mountain to a tundra and permafrost zone at top.