基于GIS的祁连山区气温和降水的时空变化分析

 基于ArcGIS平台Geostatistical Analyst中的Kriging插值方法,和Spatial Analyst中的Surface Analyst,分析了祁连山区18个气象站点1960\_2005年气温、降水的数据,并且空间化显示了各年代间的气温、降水变化。结果表明:①1960\_2005年祁连山区的气温呈显著的上升趋势,升幅基本在0.5 ℃/10a左右,20世纪90年代中期以后气温上升最为明显,变幅最大超过1℃。②祁连山区的气温变化和西北地区的气温变化有很好的同步性。冬季气温分布趋势与夏季相同,但冬季南北坡的温差明显小于夏季。各月的平均气温直减率差别大,冬季气温直减率较低,春季气温直减率较大。③分析了祁连山区降水的累积距平,祁连山的东、中、西三段的降水在80年代以前都是呈下降的趋势,在80年代以后表现为显著增加,并且中部表现最为明显。在祁连山的北坡、南坡和的降水总体趋势变化也是在80年代,在80年代以前呈下降趋势,而80年代后为上升趋势。④祁连山区的降水呈上升趋势,降水具有明显的区域性和季节性, 从东南向西北逐渐减少,冬季降水均在13 mm以下,而在夏季降水量最高可达247 mm。

Spatio-temporal Variations Analysis of Air Temperature and Precipitation in Qilian Mountainous Region Based on GIS

Based on the technology of ArcGIS, Kriging Interpolation Method and Surface Analyst, the monthly mean air temperature and precipitation data during 1960 through 2005 from 18 weather stations in Mt. Qilian region were analyzed. Their spatio-temporal variations are as follows: ①There was an obvious ascending trend of the air temperature in Mt. Qilian region from 1960 through 2005, with an increasing rate at about 0.5 ℃/10a; the ascending trend was the most obvious in the middle 1990's, and the increasing rate was more than 1 ℃/10a. ②The change of air temperature in Mt. Qilian region kept well in phase with the change of air temperature in northwestern China. The distribution regimes of air temperature were same in summer and winter, but the temperature difference between north and south slope of the mountain was smaller in winter than that in summer. The monthly lapse rates of mean temperature differed seasonally, with low value in winter and high value in spring. ③There was an ascending trend of precipitation in Mt. Qilian region from 1960 through 2005, and the precipitation distribution changed regionally and seasonally; precipitation reduced from south-east to north-west, and precipitation was less than 12 mm in winter and reached 230 mm in summer.