Reasons for the small Mediterranean climate distribution area in the Cape of Good Hope (geographical knowledge)

Regional differences of Mediterranean climate

Jin Jianhui/Chaoyang Teachers College, Liaoning Province (122000)

The Mediterranean climate is a widely distributed climate type in the world, mainly distributed on the west coast of the mainland between 30-40 degrees north and south latitude, and "rainy Ciel Phantomhive in winter" is the main feature of this climate. However, due to the influence of underlying surface, topography, ocean current and land-sea distribution, the distribution and climate characteristics of Mediterranean climate vary from place to place.

I. Regional differences in the latitude distribution of the Mediterranean climate

The Mediterranean climate is mainly distributed in the west coast of the mainland at 30-40 degrees north and south latitude, but the specific analysis shows that the latitude distribution is also very different. The Mediterranean coastal area with the most typical Mediterranean climate and the widest distribution area in the world has a high latitude distribution, and its northern end can reach more than 46 degrees north latitude, which is mainly caused by the existence of the Mediterranean. Due to its large area (about 2.5 million square kilometers) and wide latitude (about 3 1 0-45 degrees north latitude), the Mediterranean has formed a typical Mediterranean climate. In winter, the sea surface temperature is high, which forms a local low pressure at the low altitude in this area, which has the effect of attracting Atlantic polar cyclone and prompting air masses of different properties to meet here to form a front, thus making the Mediterranean coastal areas rainy in winter; In summer, on the other hand, the temperature in the Mediterranean is lower than that in the surrounding continent, and the air pressure is higher, which strengthens the subtropical high, thus making the summer here more sunny and dry. Due to the limitation of land and sea distribution, the latitude distribution of Mediterranean climate in South Africa and Australia is low, with South Africa not exceeding 32 degrees south latitude and Australia reaching more than 37 degrees south latitude.

Second, the regional differences in the east-west extension (longitude distribution) of the Mediterranean climate.

Because the Mediterranean Sea goes deep into Asia, Europe and Africa, there are no tall mountains in the north and south, and the Mediterranean climate in coastal areas extends the widest from east to west. Although the Mediterranean climate in the southwest coastal area of Australia is separated by the ocean, it still extends widely eastward (about east longitude 1 15 degrees to east longitude 145 degrees). The Mediterranean climate in North and South America cannot extend eastward because it is blocked by coastal mountains, and can only be distributed in narrow coastal areas. Due to the small land area at the southern tip of Africa, the east-west extension of the Mediterranean climate there is also very limited.

Third, the regional differences between Mediterranean climate and summer temperature.

"Dry summer" is an important feature of Mediterranean climate, but "dry summer" is not necessarily a hot summer. Due to the different intensity of coastal cold current, the temperature difference in summer is caused. In the Mediterranean coastal areas, which are hardly affected by the cold current, the summer temperature is high and the weather is hot, with the hottest monthly average temperature reaching 24-28℃. However, due to the weak cold current in Western Australia, the summer temperature in the Mediterranean climate zone along the southwest coast of Australia is not too high, and the average temperature in the hottest month is 18-24℃, while the summer temperature in other Mediterranean climate zones (the west coast of North America, South America and South Africa) is low, and the average temperature in the hottest month is16-2/kloc-0℃.

Four. Regional differences in climate and precipitation in the Mediterranean (see table below)

According to the analysis of the above precipitation data, the annual precipitation of Mediterranean climate is generally between 200- 1000mm, and the higher the latitude (the longer it is affected by the westerly belt), the more precipitation; The closer to the ocean (the greater the influence of the westerlies), The more precipitation.