短期水文气象资料估算哈尔滨至同江冰厚度
Calculating river ice thickness from Harbin to Tongjiang using short-term hydrological and meteorological data
-
摘要: 为估算松花江干流哈尔滨至同江段相距660 km的河冰厚度分布,用松花江干流短期实测水文和气象资料,在静态水域斯蒂芬冰厚计算公式基础上,引入水流流速的动能效应。假设河流内水流量相等,建立流速同河流宽度的简单关系,估算了一些调查断面的冰下平均流速;用地表温度资料,对干流域内缺少气象资料的调查断面,在证明结冰期间属于同一天气系统的前提下,用距离平方反比法进行空间插值。最后获得松花江干流河冰厚度统计关系式。用计算的哈尔滨至同江河冰厚度与有限的实测数据比较,发现该方法能够体现人为调节流速对冰生长速率的影响,对计算长距离河冰厚度具有一定精度。Abstract: In order to calculate the river ice thickness distribution from Harbin to Tongjiang about 660 km along Songhua River,and based on the fact of the short-term hydrological and meteorological data along Songhua River,the kinetic energy effect of fluid velocity under ice cover on ice growth is added into Stefan equation which is commonly needed meteorological data for the single point ice thickness calculation under the state water conditions.In the case with scarce measured fluid velocity data under ice cover,it is assumed that water flux and roughness is same in the supposed river,then the relationship between the fluid velocity and the river width is set up,and some mean fluid velocities under ice covers at different sites are evaluated. And in the case without measured meteorological data along the river,the average daily surface temperature is interpolated by using the method of inverse distance squared if the ice forms under the same weather system during the ice period.The statistical relation is obtained following the theoretical analysis and limited hydrological and meteorological data.Based on the calculated results from Harbin to Tongjiang along Songhua River,660 km long,it shows that the human interference in the fluid velocity affects the ice growth rate and the calculation of longer river has higher accuracy.