近50年蒙古高原东部克鲁伦河流域气候变化分*析

Analysis of Climatic Change in Basin of Kherlen River of Mongolia Plateau for the Past 50 Years

利用克鲁伦河流域典型区域1958-2005年的气温和降水资料,采用气候统计诊断分析方法,分析了气温和降水的年际和四季的变化特征。结果表明,近50年间,研究区气温呈显著的升高趋势,降水量波动性较大,总体上呈缓慢的增加趋势,变幅不明显,属于气候自然波动的范围;短时间尺度上,1998-2005年降水量呈下降特征。气温和降水量二者5年滑动平均值和20年滑动平均值的变化均呈增加趋势,但5年滑动平均值增加幅度较大,20年滑动平均值的变化则是一个平缓上升的过程,说明在短的时间尺度内气候变化更加明显。包括温度与降水在内的主要气候特征值的趋势性变化,加剧了蒙古高原东部地区干旱化的程度,因此有效防治土地荒漠化迫在眉睫。

The annual and seasonal variation analyzed according to temperature statistical characteristics of temperature and precipitation are diagnosis by using the temperature and precipitati- on data in the typical area of basin of River Kherlen from 1958 to 2005. The results show that for the past 50 years the temperature rose notably, the precipitation fluctuation was great and exhibited a large increasing trend, but the trend was not notable and in the range of natural cli- matic fluctuation. In a short time scale the precipitation of 1998 -2005 showed a decreasing trend. The average variation of temperature and precipitation showed an increasing trend for ev- ery five years and every twenty years, the increasing magnitude was higher in the previous case, in the lattest case, however, it showed a slow increasing trend, which showed that cli- matic changes were more notable in a short time scale. The main climatic characteristic variations, containing temperature and precipitation, accelerate the drought degree of eastern area in Mongolia Plateau. So it＇s imminent to prevent land desertificating efficiently.