| The paper uses such indexes collected by 171 experiment stations in northwest China between 1961 and 2003 as average monthly temperatures, the highest and lowest monthly temperatures, rainfalls, accumulative temperatures above zero ℃ and ten ℃ and the negative accumulative below zero ℃ to analyze the patterns for the climatic changes of northwest China. The average monthly temperatures, the highest and lowest monthly temperatures, the rainfalls, the accumulative temperatures above zero ℃ and ten ℃ in 19872003 remarkably increased compared with those in 19611986; Of them the lowest temperature did rise with the highest range and the temperatures in winter increased with a higher range than those in spring. The climatic changes of northwest China resulted from the contributions of the lowest temperatures. Meantime, the negative accumulative temperatures below zero℃ obviously declined, the rainfalls increased in the western part of northwest China and decreased in the eastern of north of China with the divide line moving along yellow river. Northwest China tended to become humid in its western part and warm in its eastern part so that warm-liking crops increased in planting area and overwinter crops moved toward north beyond their planting boundary. |