A distributed hydrological forecast system and its application in predicting the flood caused by Mangkhut

Abstract

The currently used hydrological forecast system in China is mainly focused on flood, and the flood forecasting frameworks are typically based on point discharge measurements and predictions at discrete locations, hence they can't provide spatio-temporal information of various hydrological elements, such as surface runoff, soil moisture, ground water table, and flood inundation extents over large scales and at high spatial resolutions. The use of distributed hydrological model has recently appeared to be the most suitable option to bridge this gap. An open source GIS-based distributed hydrological forecast system was established recently, and the watershed delineation and hydrological modelling were integrated together seamlessly. The time and human consuming work of processing the spatial data in building distributed hydrological model could be reduced significantly, and the spatial distribution of hydrological information could be quickly simulated and predicted using this system. The system was applied successfully to forecast the flood caused by super strong typhoon “Mangkhut” which attacked the south China in 2018.