How did the savannah climate in southern Australia come about?

The southern part is controlled by the alternate subtropical high and westerly wind belt, which belongs to the Mediterranean climate, but the monthly temperature is above 15 degrees, and the natural landscape is a savannah climate, so it belongs to the savannah climate.

It is located in the alternate control area of the subtropical high pressure zone and the westerly wind zone, and is formed by its influence.

The southern subtropical high pressure zone and the westerly wind belt alternately control the formation.

The southern subtropical high pressure belt and the trade wind belt alternately replace each other.

The reasons for the formation of tropical rainforest climate in northeast Australia are: under the influence of the equatorial low pressure zone, the updraft prevails all year round, and the warm and humid airflow gathers near the equator, converges and rises, and the water vapor contained in it is easy to form clouds and cause rain; Or it can be blown by the trade winds, which bring warm and moist air, making it rainy all year round.

In addition, the distribution of land and sea and vegetation also have a certain influence on the climate of tropical rainforests. The tropical rainforest climate is located near the sea or in large river basins, so that the rainfall is abundant and the temperature difference is small; The transpiration of vegetation is strong, making the environment more humid.

Climatic characteristics

Australia is located in the southern hemisphere, and although the time difference is only 2-3 hours from China, the seasons are completely opposite. Summer is from December to February, autumn from March to May, winter from June to August, and spring from September to November. The average annual temperature is 27 in the north and 14 in the south.

Australia straddles two climatic zones, with the northern part of the tropics and January-February being typhoon due to its proximity to the equator. Southern Australia is temperate. The Midwest is a desert with drought and little rain, high temperatures, and large temperature differences; In the coastal zone, rainfall is abundant and the climate is humid.

The tropical desert climate is distributed along the Tropic of Capricorn.

to the interior of the continent or the west coast of the continent between 30°N, and extend to inland areas, such as northern Africa, the Arabian Peninsula in Asia.

and the Australian desert region are typical examples.

The tropical desert climate of Western Australia is the main cause

1) The Tropic of Capricorn runs through the central part of the continent, and most of the area is subject to tropical high pressure throughout the year.

Control, due to the sinking of the air flow, it is not easy to precipitate.

2) The contour of the Australian continent is relatively complete, there are no large bays deep inland, and the continent is wide from east to west and narrow from north to south, which expands the area controlled by the return high pressure belt.

3) The large mountainous watershed is close to the eastern Pacific coast, which reduces the influence range of the southeast trade winds and the warm current of eastern Australia, so that the rainy areas are confined to the eastern Pacific coast, while the vast inland and western regions have scarce precipitation.

4) The vast central and western regions, the terrain is flat and does not have a lifting effect. Western Indian Ocean.

The land breeze blows along the coast, and there is a cold current from Western Australia passing along the coast, which has the effect of cooling and dehumidifying. So the Australian desert area is particularly large, and it goes straight to the west coast.

Australia's northern savannah climate is due to the influence of geographical location and vertical climate zones. Most of the Likong states in this area are very dry for a long time, and the rainy season is very short, and there are even months of no precipitation in the year. This climatic feature has had a greater impact on local agricultural production, while also exacerbating problems such as drought and fire.

In northern Australia, there is no extensive cloud cover due to atmospheric circulation, which allows the sun to shine directly on the land, making the land and air temperatures in this area relatively high. In addition, due to the proximity of this region to the equator, its climate has very strong seasonal characteristics. During the Southern Hemisphere summer, the positive energy of the Southern Hemisphere Sun shines directly on this part of northern Australia, resulting in very high temperatures and humidity in this area.

However, in the Southern Hemisphere winter, the Southern Hemisphere sun shines obliquely on this area, resulting in cooler temperatures and less rain.

From the above reasons, it can be seen that the reason for the formation of the climate of the savannah in northern Australia is not caused by a single factor. In addition to the geographical location of the north and the seasonal influence, the distribution of the sea and land is also an important factor affecting the climate. At the same time, in today's increasingly severe climate change, the climate in this region is changing and requires more attention to mitigate the impact on the natural environment and human survival.

Due to its location on the leeward slope of the southeast monsoon and controlled by the subtropical high, the eastern part of Australia has less precipitation, but the dry and wet seasons are obvious, forming a savannah climate. Due to the seasonal movement of the global pressure belt and wind belt, the southern part of Australia is controlled by the southward moving subtropical high in summer, and the downdraft prevails, which is dry and rainless, forming a dry season. In winter, it is controlled by the wet westerly winds that move northward, creating a wet season.

The savannah climate is mainly distributed on the north and south sides of the tropical rainforest, generally between 10 degrees and 23 degrees 26 minutes north and south latitudes. High temperature all year round, long summer without winter, and clear dry and wet seasons are its outstanding features. It has high temperatures throughout the year, and in some places it is even hotter than in the rainforest areas.

However, the rainfall is concentrated in 4-6 months of the year, which becomes the rainy season (controlled by the equatorial depression); Another 4-5 months almost no rain falls, becoming the dry season (trade wind belt control). Therefore, the natural landscape is very different from the tropical rainforest. There are not many species of wood here, the distribution is sparse, and the grass grows very high, which is often called savanna.

The savanna is an ideal habitat for herbivores and carnivores, so it becomes the kingdom of animals. There are many species and numbers of animals, and there are many famous natural zoos. The seasonal change of scenery here is noticeable:

When the dry (dry) season comes, the trees lose their leaves and wither and turn yellow everywhere; When the wet (rainy) season arrives, it is full of verdant greenery and lush greenery.