两种干湿气候类型评价方法在内蒙古地区应用比较

Two kinds of dry and wet climate type evaluation method application in the Inner Mongolia Region

Holdridge可能蒸散率(PER)和徐文铎湿润指数(HI)在内蒙古地区的应用结果表明:两种干湿气候类型划分差异主要体现在半干旱和亚(半)湿润区,其余气候类型地域分布比较一致。其年代变化的共同点是半干旱区+干旱区+极干旱区面积逐年增加,亚(半)湿润区+湿润区面积逐年减少。PER分类与降水量分布规律明显,而HI分类更多体现了温度和降水的综合影响。在考虑下垫面特征的情况下,徐文铎湿润指数更符合内蒙古地区干湿气候带划分。30 a温度与降水相关分析表明:温度呈显著增加趋势,而降水的下降趋势属正常气候波动。

The study of dry wet climate type was very common at home and abroad,but it hasn＇t seen Holdridge potential evapotranspiration rate（PER）method and Wen-Duo Xu Humidity index（HI）about dry and wet climate type division contrast report. The paper uses 116 weather station data（1984-2013）and analyze the types of dry and wet climate change in the Mongolia by the two methods. The results from PER indicated that there are arid region and extremely arid areas 278 495 km2,semi-arid zone andsubhumid area 278 495 km2,humid region278 495 km2;while result from HI showed arid regionand extremely arid areas 388 832 km2,semi-arid zone and subhumid 579 754 km2,humid region 278 495 km2. The difference division from two methods mainly located in the semi-arid and subhumid area. The same trends of interdecadal variation was that total area of arid region and semi-arid zone is increasing,but semi-humid area is decreasing with years. PER and rainfall distribution is obvious,and HI can illustrate more comprehensive influence of the temperature and precipitation. Considering the characteristics of underlying surface conditions the HI is more suitable for dividing the wet and dry area of Inner Mongolia region. Moreover,from analysis of 30 years temperature and precipitation,Inner Mongolia region,has a distinct warming and drying trend,but the decreasing trend of precipitation belongs to normal climate fluctuations.