沧州南部地区1970年以来气候变化特征分析

Analysis on characteristics of climate change in southern district of Cangzhou since 1970s

利用Mann-Kendall法、R/S法、小波分析等统计方法分析沧州南部降雨、蒸发和气温3个主要气候因子1970年以来趋势性、持续性、突变性、周期性等的演变规律。结果表明:降雨年际变化剧烈,蒸发和气温年际变化相对较小。降雨和蒸发存在微弱下降趋势,而气温存在显著升高趋势;3个气象要素都表现出持续性特征,且气温持续性最强,Hurst指数达0.91,降雨持续性最弱,平均Hurst指数仅为0.59;降雨在20世纪70年代中后期至80年代初、80年代末至90年代初及90年代中后期发生了3次突变,气温在1985年、1989年和1997年发生3次突变,蒸发序列突变位于1983—1985年以及1989—1990年2个时期;降雨以16 a周期分量最为强烈,同时还存在6—8 a和2—4 a周期分量;气温以趋势性变化为主,周期分量很微弱;蒸发存在15 a1、0a和6 a周期分量,且三者震荡强度接近。

The Mann-Kendall,R/S,and wavelet analysis methods were used to analyze statistical characteristics,including tendency,durative,mutation,periodicity of three main climatic factors,precipitation,evaporation and temperature in the southern district of Cangzhou City since the 1970s.The results show that precipitation varies sharply from year to year,while evaporation and temperature change little.Precipitation and evaporation tend to decline slightly,but temperature increases significantly.In addition,all of the three main climatic factors are characterized by durative,of which temperature is the most intensive,with its Hust index of 0.91,but precipitation is the least,with its Hust index of only 0.59.The mutations of precipitation occurred from the middle and late 1970s to early 1980s,from the late 1980s to early 1990s and in the middle-1990s.Temperature had three change points in 1985,1989 and 1997,and the mutations of evaporation occurred from 1983 to 1985 and from 1989 to 1990.The periods of precipitation are 16 years,6-8 years and 2-4 years,of which the 16-year period is the most intensive.evaporation has three periodic components,namely 15 years,10 years and 6 years,respectively.There is no distinct period for temperature.The oscillation intensities of precipitation,evaporation,and temperature were approximately the same.