关键词: 降水时空分布, 降水强度, 雨季划分, 典型旱涝年, 新疆博州地区

Abstract:

The day-to-day precipitation data from 1971 to 2000 that recorded at four meteorological stations over Boertala Mongolia Autonomous Prefecture (Bole region for short) were used to analyze the spatial-temporal distribution of precipitation by the method of static statistics, and to determine the typical drought or flood year by the Z-index standard. The results are shown as follows: ①The area above 1200 m is semiarid, most of the others are arid or severe arid where the extreme precipitation events occur more and the natural ecological environment is fragile. ②The yearly or monthly precipitation is often less than their multi-mean value. ③Precipitation is very little from December to next February, during which rainfall in west is more than that in east, vice via in the other months. ④It often rains during April-September, but extensive drought and local flood often coexist from May to July. ⑤There are two rainy seasons(accumulating five ten-day) in the mountains, where the monthly rainfall appears two high peaks in one year, with the main occurs in July and the subordinate in May. There is only one rainy reason (lasting two ten-day) in the other regions, where the monthly rainfall appears one peaks in May. ⑥The drought or flood degrees are different in sub-regions even under same climate background, the spatial distribution of precipitation is extremely complicated.

Key words: spatial-temporal distribution of precipitation, precipitation intensity, determination of the rainy season, typical drought or flood year, Bole region in Xinjiang