Tibetan Plateau

Author: Leandro Alegsa Creation date: November 13, 2022

The Tibetan Plateau, also known as the Qinghai-Tibetan (Qingzang) Plateau, is a vast, high plateau in Central Asia. It covers most of the Tibet Autonomous Region, the Qinghai Province in China, and Ladakh in Kashmir, India.

The Tibetan Plateau occupies an area of around 1,000 by 2,500 kilometers, and has an average elevation of over 4,500 meters. It is the highest and largest plateau in the world.

It was formed by the same forces which formed the Himalayas, namely, the movement of the Indian continental plate into Asia. The Plateau has an great effect on climate, and is the main cause of the monsoon rains.

In Amdo, in the northeast of the Tibetan highlands...

Geography

The highlands are divided into the western Changthang in the Tibet Autonomous Region (AGT) of the People's Republic of China, as well as the central Yarmothang highlands largely located in the Chinese province of Qinghai, the island-like Qaidam basin in Qinghai to the northeast, and the mountainous lands in the transition to the border of Sichuan province. It encompasses most of historic Tibet as well as what is now the Chinese Autonomous Region of Tibet (AGT).

In the north, the hilly to medium mountainous plateau is bordered by the mountain ranges of the Altun-Qilian-Kunlun. In the west the Karakorum Mountains and in the south the Transhimalaya - or depending on the author the Himalaya - form the borders. In the east, the Tanggula Shan and the Bayan Har Mountains are understood as parts of the highlands, while the mountain ranges of the (extended) Hengduan Shan form the eastern border.

Climate

Although the entire highlands of Tibet lie in the subtropical climate zone, the distinct high altitude climate results in extrazonal vegetation that is more reminiscent of cold temperate to polar climates. In contrast, however, there are some crucial differences to be noted:

The climate is characterized by high temperature differences between day and night and by rapid, strong weather changes. The average temperature in Changtang varies, being higher in the south and west than in the north and east. At Lake Aru Co in Rutog County, the average temperature is -8 degrees Celsius, while in Shuanghu in the northeast it is -24 degrees Celsius. The annual temperature fluctuations are not as extreme as the daily ones. For example, temperatures in the west can easily drop from +20 to -40 degrees Celsius. In the northeast, in Shuanghu County, temperatures do not climb above freezing even in July. The average temperature is then about -10 degrees Celsius.

The location in subtropical latitudes and high sea level leads to extremely strong solar radiation, so that the temperatures in summer are about 25 Kelvin higher than they would be without these factors (see mass elevation effect). Equally extreme is the nocturnal radiation, which can bring frosty nights even in summer. The northern half of the highlands is completely permafrost area, in the southern half this only applies to the mountains.

The shielding by the peripheral mountains results in a very dry climate, so that it rarely rains or a snow cover develops. Indirectly, this can be seen in the lack of white winter coat in the animal kingdom (as is known, for example, from the rock ptarmigan and the snow hare of other cold climates). Most precipitation occurs in summer: usually heavy thundershowers during the day and prolonged drizzle and sleet at night with westerly winds. The enormous day/night differences lead to frequent thunderstorms (annual average: 90 days), often associated with squalls and, in some regions, sandstorms. Towards the west and north, the annual mean precipitation drops to 20 to 80 mm.