河西走廊大风持续时间的气候特征

分析了河西走廊1980~2010年一日大风持续时间的气候特征。结果表明:河西走廊一日大风平均和最长持续时间的空间分布特征与大风日数基本一致,总体上自东向西、自南向北增多,且随海拔高度的升高而增多。全区年大风平均持续时间在7~207 min之间,平均为65 min。大风一日最长持续时间是1 390 min。酒泉市大部、永昌、民勤和乌鞘岭年大风平均和最长持续时间偏长,其余地方偏短。各季大风平均和最长持续时间,春季最长、冬季次长、夏季最短、秋季次短。年一日大风持续时间的频率为偏态分布,在0~2 h的累积频率为0.67。风速偏小站大风的持续时间基本为0~12 h,风速偏大站大风的持续时间在12~24 h,这说明风速越大,大风的持续时间越长。

Climate Characteristics of Gale Duration in Hexi Corridor

Based on the minutely gale duration at 19 weather stations in Hexi Corridor during 1980-2010,the climate characteristics of daily gale duration on the strong wind days were analyzed.The results indicated that the spatial distribution of average and longest daily duration of gale was basically in accord with the gale days.As a whole,the daily duration of gale increased from east to west and from south to north,and increased with increase in altitude.With respect to annual character,the average daily duration of gale was be-tween 7 to 207 minutes,and the mean value was 65 minutes in whole region of Hexi Corridor.The longest daily duration of gale was 1 390 minutes,and which in Minqin,Jiuquan,Yongchang and Wushaoling was relatively longer than that in the other regions.In four seasons,the average and longest daily duration of gale in spring,winter,fall,and summer reduced in turn.The frequency distribution of the daily duration of gale was abnormal.The cumulative frequency of gale daily duration between 0 to 2 hours was 0.67.The daily duration of gale at the stations with a small wind speed was generally 0 to 12 hours,while that of the stations with a large wind speed was 12 to 24 hours.Thus it can be seen that the daily duration of the gale was longer as the wind speed became larger.