基于降水气候强迫的一种地表径流估计方法  

A ESTIMATION METHOD OF SURFACE RUNOFF RATIO BASED ON CLIMATIC FORCING OF PRECIPITATION

作　　者：刘晶淼[1] 丁裕国[2] 周秀骥[1] 李云[2] 

机构地区：[1]中国气象科学研究院,北京100081 [2]南京气象学院,南京210044

出　　处：《气象学报》2004年第3期285-293,共9页Acta Meteorologica Sinica

基　　金：国家自然科学基金项目 ( 4 0 2 75 0 3 0 );国家重大基础研究项目 (G19980 40 911)

摘　　要：文中从地表水分平衡的物理机制出发 ,引进降水概率统计分布理论 ,推导出一种由降水气候强迫形成的次网格尺度非均匀径流率计算方法。应用于mosaic方案 ,可进一步计算区域平均径流及产流和汇流。试验证明 ,对于不同物理性质的地表而言 ,由于其土壤入渗能力的差异 ,相同降水气候强迫所能生成的径流量及其相对比值是不同的 ,例如干旱区与湿润区就有很大差异。同时 ,不同空间分布概率的降水量 ,不同站点的地表性质、土壤水力学条件等物理因素的千变万化 ,可使径流特征的空间分布具有很大变异性。因上述各种因素的综合影响 ,由降水气候强迫所形成的地表径流具有特定的非均匀分布是必然的。A calculation method of subgrid scale runoff ratio over the heterogeneous surface is derived using the distribution theory of probability statistics on the basis of physics mechanism of water balance over land surface. The mean runoff and its out growth and confluence over a grid region may be calculated when this method is used in mosaic scheme. It is demonstrated by test that due to difference of soil penetrability, even if the rainfall force is same for different soil types, the runoff characteristic are also different. For any special scale, the surface heterogeneity of soil characteristic、land cover and climatic force are all exert influence on the heterogeneity of runoff. In this paper, the dependability and availability of this calculation method are verified from some example using actual observation data. The significance of this study is that the runoff ratio at any region or point may be expressed as multi variables function of soil characteristics and PDF parameters of rainfall distribution. The multi variables function may be combined into land surface hydrological model, and some forced experimentation of land surface runoff on rainfall and soil characteristics parameters can be carry out. The availability of rainfall and soil moisture data makes the forced experimentation to be implemented easy.

关 键 词：地表水分 降水 地表径流 次网格尺度 

分 类 号：P426.613[天文地球—大气科学及气象学]