巴丹吉林沙漠湖泊水面蒸发与气象要素的动态关系

Dynamic Relationship between Lake Surface Evaporation and Meteorological Factors in the Badain Jaran Desert

巴丹吉林沙漠腹地分布有大量湖泊,水面蒸发是湖泊水循环乃至整个沙漠水循环的关键控制因素。本文以在沙漠腹地湖泊——苏木巴润吉林建立自动气象站监测的2012年9月11日至2013年3月26日和2013年5月8日至2015年6月23日的长序列气象、蒸发数据,以及2012年9月13日至2014年6月20日的湖底压强数据为基础,在多时间尺度下分析湖泊水面蒸发与气象要素的动态关系。利用多元线性回归模型、非线性空气动力学模型和Penman公式对逐小时、逐日和逐月蒸发量进行模拟分析。结果表明：随着时间尺度的提升,蒸发量与同期气象要素之间的相关性增强。在逐小时尺度下,蒸发与同期气象要素的相关性较弱,用多元线性回归模型拟合效果不佳。在逐日和逐月时间尺度下,蒸发量与同期气温和水温的相关性最高,利用多元线性回归模型或非线性空气动力学模型可以较好地模拟蒸发量。Penman公式计算的逐日蒸发量在夏季偏大而冬季偏小。研究结果可为沙漠湖泊水量蒸发的评估提供科学依据。

A large number of lakes are distributed in the Badain Jaran Desert located in northwest China. Water evaporation is a key factor in lacustrine water cycle and even an entire desert. In this paper,the dynamic relationships between evaporation and meteorological factors were analyzed based on the long-term meteorological and evaporative data monitored by automatic weather station at the Sumu Barun Jaran Lake from September 11,2012 to March 26,2013 and from May 8,2013 to June 23,2015 as well as the pressure intensity data at the lake bottom observed from September 13,2012 to June 20,2014. The multiple linear regression model,nonlinear aerodynamic model and Penman equation were used to simulate and analyze the hourly,daily and monthly evaporations. The results indicated that the correlations between evaporation and meteorological factors were enhanced with the time prolonging. At the hourly time scale,the correlations between evaporation and meteorological factors were poor,and the evaporation could not be simulated well by the multiple linear regression model. At the daily and monthly time scales,evaporation was closely correlated with air temperature and water temperature in the same period,and the evaporation could be modeled well by the multiple linear regression model and nonlinear aerodynamic model. The daily evaporation modeled by Penman equation was higher in summer but lower in winter. The results could provide a scientific basis for assessing the water consumption by lake surface evaporation in desert.