塔克拉玛干沙漠腹地地表能量平衡闭合特征

Surface Energy Balance Closure Characteristics in the Hinterland of Taklimakan Desert

利用塔克拉玛干沙漠腹地塔中陆气相互作用观测试验站2014年6月至2015年5月的感热通量(H)、潜热通量(LE)、净辐射(R n)、地表土壤热通量(G 0)资料,应用能量平衡比率(EBR)法与最小二乘法(OLS)分析沙漠下垫面地表能量平衡闭合特征。结果表明:LE日变化不明显,H、R n、G 0均呈单峰型变化趋势,且有明显的季节变化特征,表现为夏季>春季>秋季>冬季。沙漠腹地存在能量平衡不闭合现象,白天EBR在0~1之间缓慢波动变化,夜间EBR波动较大。白天、夜间地表能量平衡闭合状况分别为0.827、0.410。不同季节地表能量平衡闭合状况夏季(0.893)>春季(0.835)>秋季(0.787)>冬季(0.698)。不同天气条件下,能量平衡比率晴天>阴天>沙尘暴,晴天和阴天EBR变化不大,符合EBR一般变化规律,沙尘暴天气过程EBR出现瞬时异常闭合现象。

Based on the energy fluxes data of the observation experimental station of land-atmosphere interaction in the hinterland of Taklimakan desert from June 2014 to May 2015,the energy balance ratio(EBR)method and the least square method(OLS)were used to analyze the surface energy balance closure characteristics of desert underlying surface.The results show that all the components of energy fluxes showed a single peak trend,and there were obvious seasonal variation characteristics except latent heat flux(LE),and they were from high to low in summer,spring,autumn and winter.There was an unclosed energy balance in the hinterland of the desert.The energy balance ratio(EBR)fluctuated slowly between 0 and 1 during daytime,and it fluctuated greatly at night.The surface energy balance closure condition was 0.827 in the daytime and 0.410 at night.The surface energy balance closure condition from high to low in summer(0.893),spring(0.835),autumn(0.787),winter(0.698).Under different typical weather conditions,the EBR from high to low under sunny day,cloudy day,sandstorm conditions,and the EBR changed little on sunny day and cloudy day,which accorded with the general variation law of EBR,during sandstorm weather process EBR appeared instantaneous abnormal closure phenomenon.