The monsoon which sustains this lush and fertile valley owes its very existence to the Tibetan plateau. Like a giant hotplate, the plateau heats up in the spring and summer. 
The change in air pressure draws in warm moist air from the Indian Ocean in the south. Thanks to this, over a billion people from India to Burma benefit from the monsoon rain that this wind brings with it. Tibet is the engine that drives the fertility of a whole subcontinent. But Tibet has an even greater role in the ecology of the region. 
Clues to this function are found in a legend that pre-dates even the ancient Tibetan culture and which still draws pilgrims from all over the world. 
Several world religions believe in a mythical mountain that's equivalent to the Garden of Eden.
Its peak has four faces, aligned to the points of the compass, and from its summit four rivers are said to flow to the four quarters of the world. 
Thanks to its life-giving waters, this mountain is known as the "axis of the world ". In one of the remotest areas of Tibet, there's a place where this legend takes physical form.
That place is Mount Kailash. 





 


多亏了高原的存在，才有了为绿色富饶峡谷带来活力的季风。高原像一个巨大的加热板, 春温夏暖。气压的变化引来了南面印度洋的温热潮湿的空气，幸亏这样，从印度到缅甸的十亿多人，都得益于季风带来的季风雨。西藏就是保持整个次大陆肥沃的动力。但是西藏在地区生态方面扮演着更重要的角色。这个角色的线索可以追溯到古藏文化的传说当中，而这个传说至今还吸引着来自全世界的朝圣者。世界上一些的宗教相信一座神话中的山是伊甸园般的存在。它的顶部有四个面，排成罗盘的四个方向，从它的顶部有四条河流向世界的的四方。由于这里的生命之泉，这座山被称为“世界屋脊”。在西藏最偏僻的区域之一,有一个地方应验了这个传说。这就是伽拉萨山。