1960-2016年甘肃省极端气候事件变化特征  

Changes of extreme climate events in Gansu Province from 1960 to 2016

作　　者：梁晓燕[1] 牛震敏 许兴斌[1] 王乃昂[1] Liang Xiao-yan;Niu Zhen-min;Xu Xing-bin;Wang Nai-ang(Center for Glacier and Desert Research,College of Earth and Environmental Sciences,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]兰州大学资源环境学院,冰川与沙漠研究中心,兰州730000

出　　处：《兰州大学学报（自然科学版）》2020年第2期231-242,共12页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金重点项目(41530745);中央高校基本科研业务费专项资金项目(lzujbky-2017-it88)。

摘　　要：利用1960-2016年甘肃省31个气象站点的逐日平均气温、最高(最低)气温及日降水量资料,采用线性倾向估计法,根据选取的27个极端气候指数,分析了研究区域极端气候事件的时间变化趋势和空间分布规律.结果表明,霜冻日数、冰封日数、冷夜日数、冷昼日数、异常冷昼日数分别以-2.94、-2.16、-7.85、-4.5和-1.17 d/10 a的趋势减少;夏季日数、热夜日数、生长期、暖夜日数、暖昼日数、异常暖昼持续日数分别以5.69、6.23、5.23、7.05、5.57和0.89 d/10 a的趋势增加;月极值指数整体表现为增加趋势,月平均气温日较差整体表现为下降趋势.各极端气温指数的空间分布差异比较明显,甘肃中南部极端气温变化幅度明显大于西北部,河西走廊地区整体变化幅度较小.强降水量、特强降水量及降水强度均呈增加趋势,中(大)雨日数、持续干(湿)期与年总降水量均呈较小的减少趋势.河西走廊极端降水总量和强度表现为增加趋势,河东地区极端降水指数大部分呈下降趋势且变化幅度大,年总降水量减少趋势以陇中地区最为明显.Based on the daily average, maximum and minimum temperatures and precipitation at 31 meteorological stations in Gansu Province, the temporal variability and spatial distribution of climate extremes were analyzed for 1961-2016. Twenty-seven indices of extreme climate events were studied and the linear regression method employed for analysis. The results show that the frost days, ice days, cool nights, cool days, cold spell duration days significantly decreased by-2.94,-2.16,-7.85,-4.5 and-1.17 d/10 a, respectively, while the occurrence of summer days, tropical nights, growing season length,warm nights, warm days and warm spell duration days showed significant increasing trends at rates of5.69, 6.23, 5.23, 7.05, 5.75 and 0.89 d/10 a. Monthly extremal indices presented upward trends on the whole;meanwhile, diurnal temperature range showed downward trends. The difference for each extreme temperature indices’ spatial distribution was obviously. The change range of extreme temperature in central southern Gansu was larger than the northwest, especially in the Hexi Corridor. For precipitation extremes, only slight changes could be observed. For very and extremely wet day precipitation, simple daily intensity index showed non-significant increases. Decreasing trends were found for a number of 10,20 mm precipitation days, consecutive dry days, consecutive wet days and wet day precipitation. The wet day precipitation and simple daily intensity index showed an increasing trend in the Hexi Corridor, while most precipitation indices had large decreasing trends in the eastern region. The wet day precipitation had been obviously reduced in central Gansu Province.

关 键 词：甘肃省 极端气候事件 时空特征 年代际变化 

分 类 号：P429[天文地球—大气科学及气象学]