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China's northwestern,northern and northeastern areas have experienced the most evident climate warming in the country for the past century,which,in turn,has worsened the aridity in northern China.
According to professor Ding Yihui,special advisor on climate change with the China Meteorological Administration,the climate became warmer most distinctly in the country's northwestern,northern and northeastern areas.Shaanxi and Gansu provinces as well as Ningxia Hui Autonomous Region and Xinjiang Uygur Autonomous Region have a higher warming intensity than the national average.
However,this climate warming has shown no signs in areas to the south of the Yangtze River,Ding said.
Zhang Jiacheng,former vice president of the Academy of Meteorology,said that a lessening temperature difference between China's northern and southern areas will weaken airflow and thus reduce the amount of vapor carried from oceans to the land.
Meanwhile,the rise in temperature will intensify evaporation.Therefore,it is speculated that the populous middle-latitude areas may experience increasingly dry weather,Zhang added.
North China entered an arid period in 1956,and the warming and drying trend has not been changed even when the region was showered with comparatively rich rainfall for several years.
Zhu Changhan,chief researcher on climactic effects with the National Climate Center,noted that if no effective response measures are taken,the local areas will fall into a vicious cycle with more serious droughts and a shortage of water resources.
According to the CMA's statistics,though rainy and snowy weather have swept across most of China from last winter to this spring,the precipitation in the central and southern regions of north China as well as the southwestern areas in northeast China is lower than the national average by 50to 90percent.Some parts in China's northern and northeastern areas have seen droughts of various degrees.
(eastday.com March 25, 2003)
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