Study On The Real-time Method Of Surface Rainfall Estimation On Basis Of Grid

Rainfall is one of the main dynamic input factors of flood forecasting and a prerequisite for ensuring forecasting accuracy. In this paper research on the real-time method of surface rainfall estimation on basis of grid has been done. This method has high practical value in real-time flood forecasting.Taking into account the characteristic of the dynamic changes of telemetry stations and time efficiency in real-time flood forecasting, in this paper, Reverse Distance Square Method is chosen to interpolate the rainfall of grid points, and the simple interpolated approach based on the impact scope of rainfall and the amount of rainfall stations—Grid Method is suggested. The key technologies of Grid Method including grid divided in basin, impact radius of rainfall and number of reference rainfall stations have been discussed with example. The parameters of Grid Method have been selected through trial and error. Using simple random sampling to simulate the failure to collect rainfall, the relation between surface rainfall calculation error and station density, station distribution, uneven spatial distribution of rainfall has been sought. Particularly in the case of the failure to collect part rainfall information, Grid Method will be used to achieve the dynamic surface rainfall estimation.