藏东南地区复杂下垫面辐射收支特征分析

利用藏东南地区进行的地气交换观测数据, 分析了典型晴天和阴天不同下垫面辐射过程的特征及其差异. 结果表明: 藏东南地区典型晴天不同下垫面总辐射均呈现出明显的日变化规律, 典型阴天各下垫面总辐射日峰值与典型晴空天气下的总辐射日峰值差值不大, 日均值显著减小; 反射辐射日变化趋势与总辐射变化一致, 但变化曲线比总辐射离散, 阴天地表反射辐射受总辐射和下垫面的综合影响; 向上长波辐射日变化幅度和量值都大于向下长波辐射, 下垫面类型对向下长波辐射没有影响. 净辐射具有明显的日变化特征, 和总辐射的相位一致, 农田净辐射的日峰值和日均值最大.

Analysis of the characteristics of radiation budget upon the complicated underlying surfaces in southeastern Tibet

Observation data from the land-atmosphere exchange experiment conducted in Nyingchi Prefecture, southeastern Tibet were applied to analyze the characteristics and differences of surface radiation on various underlying surfaces in typical sunny and cloudy days. Results showed that in typical sunny days, there is a obvious daily variation of total radiation on different underlying surfaces; the daily peak of total radiation is nearly the same between typical sunny days and typical cloudy days, with a significant lower daily mean total radiation in typical cloudy days; the daily variation of reflection radiation in typical sunny days and cloudy days is similar to total radiation but dispersed; reflective radiation in typical cloudy days is dominated by both total radiation and underlying surfaces; the daily mean value and daily variation amplitude of upward long-wave radiation is greater than the downward one; the underlying surface type has not effect on the downward long wave radiation; net radiation has obvious diurnal variation with the same phase as the total radiation; upon the farmland it always appears the maximum daily peak and maximum daily mean value of net radiation.