Translated from www.xinhuanet.com

During the golden week in the National Day, visitors to the Tibet were amazed to see the rare rain at this time of the year.

In fact, the rain on the Tibetan Plateau is different with that in other parts of China. In Tibet, an area where its lowest elevation is 5000 meters, raindrops would turn to snow accumulated on the plateau. Prof. Ding Yihui, researcher and special consultant at climate change study in SMA, told reporters that the increase of accumulated snow on the plateau may be the main course of the current weather pattern in China, which is flood in the south while arid in the north. He also said that according to the thorough analysis to Chinese climate variation in the past half century, Chinese experts have reached to a common understanding that there were two turning points in Chinese climate change. One happened before 1970s, when precipitation in the north far surpassed that in the south in terms of frequency. And the other was since 1990s, when the precipitation area moves south, bringing more rain to the south and dry weather to Northern China. In correspondence, heat source of atmosphere above the Tibetan Plateau also witnessed an telling variation, esp. after the end of 1970s, the heat source in the east and mid- Plateau weakened obviously during summer and spring.

Such a change of heat source on the Plateau led to a decrease in vapor transmission to the north, where it becomes drier, whilst more vapor to the south causes heavy rain, even flood there. Prof. Ding also pointed out that Chinese scientists proposed the relevance between snow accumulation on the Tibetan Plateau and summer precipitation in China more than thirty years ago, while the current weather on the plateau has confirmed this hypothesis. The constant weakening of Asian Monsoon in the past two decades may directly lead to the flood in the south and arid in the north of China, he added.

Liu Wei, chief engineer of monitoring station for geological environment of the Tibet Autonomous Region told reporters that in the past five years, precipitation on the Tibetan Plateau had increased by 50mm plus. Autumn and winter of the plateau, which used to be clear and dry, now witnessed frequent rain and snow in this area.