DEVELOPMENT OF LARGE SCALED HYDROLOGICAL MODEL INCORPORATING THE TURBULENT ENRGY BALANCE IN THE SURFACE BOUNDARY LAYER

分布式水文模型在业务化的基础上，有可能结合卫星遥感数据或雷达数据，提供高精度、高分辨率的水文模型。在开发高等级径流模式中的问题是缺乏对表面边界层中湍流输送及其在水文过程中的作用的了解。本文对分布式水文模式中引入地面边界层的力学机制以及分布式模式向降雪-融雪季节的发展进行了初步研究，第一阶段利用车载湍流仪对风和温度的湍流脉动进行了现场观测。结果表明，在风场、温度场和动量、热量的湍流输运过程中，风场和温度场的湍流特征是一致的 关于我们 本文尝试将分布式水文模型应用于降雪-融雪季节，因为在这个季节，地面边界层的力学特性是至关重要的。在试图包括降雪和融雪现象，降雪量估计降水量的数据，假设雨量计的捕获率和降雪的海拔依赖性。利用热通量法计算融雪量，并首次将该模型应用于卫星遥感资料可利用的宇野川流域。从卫星数据中提取了流域内的积雪面积，这些数据为径流模型再现积雪面积提供了可能。第二个应用选择了Upper Tone河流域，在这种情况下，该流域的温度分布，它被输入到融雪计算，蒸发计算以及决定降雪的参数，是由数据获得的直减率决定的。计算结果与流域出口径流量和流域内各测点径流量吻合较好。因此，温度直减率是一个重要的参数，它本质上是必须通过分析地面边界层来确定的气象参数。少

The distributed hydrological model, with an operational version becoming available, bears a possibility of offering a very high-aceuracy high-resolution model with the combined use of the satellite remote sensing data or radar data. The problem in the development of a high-grade runoff model is the lack of knowledge of the turbulent transport in the surface boundary layer and its role on the hydrological processes. This study attempts to conduct a preliminary study on incorporating the mechanics of the surface boundary layer into the distributed hydrological model and developmental study of the distributed model to the snowfall-to-snowmelt season.At the first stage of this study the field observation of the turbulent fluctuation of the wind and temperature is carried out with the turbulent meters mounted on the craned vehicle. The result shows the turbulent characteristics of the wind and temperature and turbulent transport of momentum and heat is obtained.As for the developmental stud … More y of the distributed hydrological model, the application to the snowfall-to snowmelt season is attempted, as the surface boundary layer mechanics is crucial in this season. In attempting to include the snowfall and snowmelt phenomena, the snowfall amount is estimated from the precipitation data assuming the catch ratio of the rain gage and the altitudinal dependence of the snowfall. Snowmelt amount is calculated by the heat flux method.The model is first applied to the Uono River basin where the satellite remote sensing data is available. From the satellite data the snow covered area in the basin is extracted and this data offer the possibility of reproducing the snow covered area with the runoff model. For the second application the Upper Tone River basin is chosen, ln this case, temperature distribution in the basin, which is inputted to the snowmelt calculation, evaporation calculation as well as the parameter to decide snowfall, is decided from the data-obtained lapse rate. The calculation result shows agreement with the runoff discharge at not only the basin outlet but also gauged points within the basin. Temperature lapse rate thus is shown to be an important parameter which is essentially the meteorological parameter that has to be determined through the analysis of the surface boundary layer. Less