50年民勤西沙窝蒸发量与主要气象因子变化关系研究

Study on the Relationship between Evaporation Characteristics of Minqin Xishawo Desert Area for 50 Years and the Main Meteorological Factors Change

本文借助民勤典型荒漠地貌西沙窝的标准气象站观测资料,通过分析1966～2015年蒸发量与主要气象因子变化的相关关系以及关联的密切程度,揭示该区域的气候变暖与水分循环变化规律。结果表明:50年内,民勤西沙窝20 cm蒸发皿蒸发量呈下降趋势,下降速率平均在-118.7 mm/10 a范围内,影响蒸发量变化的主要因素是近地表空气湿度的不断增加与日照时数的持续下降,相关性系数分别为-0.881与0.903,均通过99%显著性水平;次要因素是年均风速逐渐下降,相关系数是0.736,通过95%的显著性检验;四季中春季蒸发量明显减小,约占去年减小的37.4%,其次是秋季,占11.43%,夏冬季变化不明显,这些因子的改变,形成了民勤荒漠区水分在热平衡中的转换表现特征。

The article is in the help of a typical desert landform in Minqin County based on the observation data of Standard Meteorological Station in the Xishawo,through the analysis of the relationship between evaporation capacity and main meteorological factors in different stages from 1966 to 2015 in this paper,and the change rule of climate warming and hydrological cycle in this region was revealed.The linear tendency estimation method was adopted to analyze the correlation relationship between evaporation pan capacity and meteorological factors changing,reflecting the close degree of the correlation.The results showed that the evaporation pan of 20 cm in Xishawo of Minqin County showed a downward trend in the past 50 years,and the average downward rate was in the range of-118.7 mm/10 a.The correlation coefficients were-0.881 and 0.903,respectively,which averagely passed over 99%significant level;the secondary factor was the decrease of annual average wind speed,the correlation coefficient was 0.736,which passed the 95%significant test;spring evaporation capacity was increased slightly in the four seasons,followed by autumn,and was decreased 11.43%.The change of these factors is not obvious in summer and winter,which forms the characteristics of energy conversion in water and heat balance in Minqin desert area.