Pastoralism and Rangeland Management on the Tibetan Plateau in ...

Photo 1: The water towers of humankind in Tibet
(photograph © Hermann Kreutzmann September 12, 2000)
2.2 The Tibetan Plateau provides a shelter to the climate systems in
China <strong>and</strong> East Asia
Towering topography brings about certain special thermal processes, making
Tibet one of the important sources of the convective system, causing summer
floods in Eastern China. In summer, the sensible heat <strong>and</strong> latent heat effects of
the plateau are so strong that they play an essential role in promoting the formation,
outbreak <strong>and</strong> maintenance of summer winds. It is an important driving
force of atmospheric motions in China <strong>and</strong> Asia. Underlying surface conditions,
particularly vegetation <strong>and</strong> snow cover, can lead to dynamic changes,
thereby affecting the stability of the atmospheric circulation in Asia <strong>and</strong> the
northern hemisphere. The Plateau’s dynamic <strong>and</strong> thermodynamic effects are
indispensable factors in the non-uniform formation of the East Asian Monsoon
water vapour distribution. The Plateau constitutes an enormous barrier against
the north-south exchange of heat <strong>and</strong> water vapour. It is a “transit point” in the
long-distance transport of water vapour from the low-latitude oceans, having a
direct impact on the occurrence <strong>and</strong> process of the monsoon rainy season of the
Yangtze River. The Plateau also has an obvious effect on the drought <strong>and</strong> flood
distribution patterns <strong>and</strong> the evolution of the ecological environment in China.
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