Compare the differences and causes of precipitation in temperate continental climates in North America and Asia.

Comparison of temperate continental climates in North America and Asia

1. The continental climate of Eurasia is more extreme

The maximum annual range in North America is about 50°C. The Eurasian continent is above 65°C; Montreal (46°N) on the east coast of North America has a higher latitude than Vladivostok (Vladivostok, 43°N) on the east coast of Asia, and is located more inland, but the former The annual range is 4.5°C less than the latter; Dawson (64°N) in the interior of North America has a higher latitude than Yakutsk (62°N) in the interior of Asia, but the former's annual range is 16.5°C less than the latter. In terms of precipitation, North America has less concentrated summer rains and less severe winter droughts than the Eurasian continent.

The continental climate of Eurasia is mainly distributed in Asia. The extreme changes in various climate elements in Asia are a reflection of the continental nature of the climate. Asia has one of the coldest, hottest, wettest and driest regions in the world. For example, the Verkhoyansk-Oymyakon region is the “cold pole” of the northern hemisphere. West Asia and North Africa are both the hottest regions in the world, and the absolute maximum temperature in the interior of Saudi Arabia can reach 50-55°C. Cherrapunji in India is the wettest corner in the world, with an average annual precipitation of more than 11,500mm. It is the region with the most precipitation in the world along with the northeastern part of Kauai in the Hawaiian Islands and the coast of Cameroon in Africa. The annual precipitation in the southern part of the Arabian Peninsula and the central Iranian Plateau is less than 100mm, and some areas even have no rain for many years, forming vast flowless areas and desert areas.

The continental nature of Eurasia is more extreme for many reasons. First of all, the Eurasian continent is larger in area, and its interior is further away from the sea. The westerly circulation and Atlantic warm and humid air currents have little impact on the Asian climate. The North American continent is much smaller than the European continent. The second reason is the atmospheric circulation, because the thermal difference between land and sea in winter and summer in North America is not as significant as in Asia, and the intensity of high and low pressure is relatively weak. This results in differences in temperature and precipitation. Thirdly, the eastern Eurasian continent has a significant monsoon climate, which results in a high concentration of precipitation. Fourth, the terrain of the Eurasian continent is high in the center and low on all sides. In particular, the terrain of East Asia is distributed in a three-level ladder shape, which is not conducive to the penetration of Pacific water vapor. The North American continent is high in the east and west and low in the middle. The height and width of the Appalachian Mountains in the east are not large enough to block the penetration of water vapor from the Atlantic Ocean.

2. The North American monsoon climate is not as typical as that of the Eurasian continent

The monsoons of the Eurasian continent are known for their strongest intensity, wide range of influence, and complex types. The Asian continent is bounded by the ocean to the east and south, starting from the Far Eastern coastal area of ??the Soviet Union in the north, passing through Japan, North Korea, and the area east of 105°E in China to Southeast Asia and South Asia. It is a typical monsoon climate zone in the world. The prevailing wind direction here changes significantly with the seasons. The prevailing wind direction changes by at least 120° between January and July, and the average frequency of the prevailing wind direction exceeds 40%. The huge thermal difference between sea and land and its seasonal changes or the seasonal movement of superimposed planetary wind belts are the main factors in the formation of monsoon climate. In summer, the wind blows from the sea to the land, which is warm and rainy; in winter, the wind blows from the mainland to the ocean, which is cool and dry, which is the unique characteristic of monsoon climate.

Although the southeastern part of the North American continent blows northwest winds in winter and southeast winds in summer, and there are weather changes, it can only be considered a monsoon phenomenon. Regarding the formation of monsoon climate, the world's largest landmass faces the world's largest ocean. The thermal difference caused by the distribution of sea and land is the fundamental reason for the formation of monsoon climate in the Eurasian continent.

3. There are differences in climate types and distributions

There are differences in climate types and distributions between North America and Eurasia, as shown in:

① North American subtropics The climate is not as vast as the Eurasian continent; this is because the main body of the North American continent is mid-to-high latitudes. ②The typical oceanic climate in North America is small and limited to the northern part of the Pacific coast. The oceanic climate in Eurasia is widely distributed; this is because the oceanic climate is deeply affected by the coastal warm current, and the Alaskan warm current that affects North America is more powerful than that of Asia and Europe. The continental North Atlantic Current is much weaker. On the other hand, it is related to factors such as the outline and topography of the continent and the western part of the continent. The mountains in the western part of the North American continent approach the coast, and Alaska stretches out to the west, forcing the Alaskan warm current to flow westward; while the western part of the Eurasian continent has flat terrain, tortuous coasts, and smooth access to the Atlantic and Arctic oceans, allowing the North Atlantic warm current to flow straight north, thereby expanding its scope of influence. . ③The polar ice sheets of the Eurasian continent are not as wide as those of North America; this is because the shape of the North American continent is wide in the north and narrow in the south. The main body of the continent is mid-to-high latitudes, with most of the area located between 30°N and 70°N. ④The subtropical summer-dry climate of the Eurasian continent is vast and typical; this climate is mainly distributed on the west coast of the continent at 30°-70°. On the west coast of the North American continent there is the tall and broad Cordillera Mountains, which is an important climate dividing line in North America. The climate in the east and west of the mountain range is completely different. The flat terrain of the Eurasian continent is conducive to the influence of ocean water vapor, which in turn promotes the formation of a subtropical summer-dry climate. ⑤The temperate continental arid and semi-arid climate of North America is small; this is related to the fact that the continental nature of North America is not as significant as that of the Eurasian continent. ⑥The tropical climate types in North America are limited, and the typical equatorial rainy climate is basically missing. The tropical dry and wet season climate, and the typical distribution of tropical arid and semi-arid climates are not as widespread as those in Asia. This is because the main body of the North American continent is at mid-to-high latitudes.