1951-2010年内蒙古霍林河流域气候变化特征

Characteristics of Climate Change in Huolin River Basin, Inner Mongolia,1951-2010

以季风边缘区的霍林河流域为研究对象,利用研究区周缘9个气象站台1951-2010年的逐月气象数据,通过对气温和降水量进行趋势分析、Mann-Kendall检验以及相关分析,探讨流域气候变化过程、特征及周期.结果表明:在1951-2010年年均气温上升2.3℃,其倾向率为0.38℃·(10a)-1,总体呈上升的趋势.其中,春季气温升幅最为明显,倾向率为0.50℃·(10a)-1.同时,年均气温以1986年为跃点,发生突变,突变后的1987-2010年平均气温比突变前1951-1986年气温高1.3℃,并存在6～8a和15a的周期律.年降水量近60a来减少了83.9mm,其倾向率为-13.98mm·(10a)-1,呈下降的趋势.其中,夏季降水量的下降最为明显,倾向率为-11.41mm·(10a)-1.年降水量以1998年为跃点发生突变,突变后的1999-2010年降水量比突变前1951-1998年下降76mm.并存在4a和8～9a的振荡周期.流域气温变化与北极涛动呈正相关,而降水量与夏季风指数呈负相关.

Based on monthly mean air temperature and monthly precipitation data from nine meteorological stations in Huolin River basin from 1951 to 2010, using climatic linear trend, Mann-Kendall test and correlation analysis methods, the spatial-temporal characteristics of climatic change in this region were analyzed in this paper. The results indicated that the annual temperature had increased 2.3 ℃, with an increasing rate of 0.38 ℃＆middot;（10a）-1 showing an up ward trendin general from 1951 to 2010 in the basin.The increase of temperature in spring was most obvious,with a changing rate of 0.50 ℃ ＆middot;（10a）-1.The annual mean temperature had an abrupt change mainly in 1986,and the temperature averaged from 1987 to 2010 was more than 1.3 ℃ higher than that from 1951 to 1986.There were significant cyclical changes with 6～8 and 15 aperiod. Annual precipitation had fallen 83.9 mm,with a decreasing rate of 13.98 mm＆middot;（10a）-1 and a downward trend in general from 1951 to 2010.The decrease of precipitation was most pronounced in summer,with adecrea singrate of 11.41 mm＆middot;（10a）-1.Annual precipitation abrupt was mainly observed in 1998, and the precipitation averaged from 1998 to 2010 was 76 mm less than that from 1951 to 1997. There were significant cyclical changes with 4 years and 8~9 years periods. It is found that the change in temperature has positive correlation with AO index and the change in precipitation negatively correlates with EAP index.