Research And Development Of A Monitor And Forecast System On Mountain Torrent Disasters

Because of the complexity of physical geographic environment, abundance ofmountains and hills, complicated variability of climate condition as well as impact ofhuman activities, flash flood disasters occur frequently in China. Flash flood breaks outsuddenly, while the forecasting period is short. Consequently, the prevention is verydifficult. The damages and losses caused by the disasters are getting worse. At present,the prevention of flash flood disasters has become one of the urgent issues of floodprevention in China.In this study, based on the needs of flash flood prevention, the requirementsanalysis of the flash flood disaster monitoring and forecasting system was established.Then, the system was developed. Critical precipitation was employed as a pre-alarmingand forecasting model in this system to warn and predicate mountain torrent timely andaccurately. The major milestones are the follows:(1) From critical levels or precipitation and water level, flash flood disasters wereforecasted. A statistical induction method was used to calculate criticalprecipitation/water level. Then, early warning information was produced by comparingcritical precipitation/water level value and the real-time monitoring data and usingwarning engines. Once the warning was generated, the inference forecasting modelwould be used to calculate the maximum flow rate of the mountain torrent.(2) According to the needs and requirements of flash flood prevention and users,the perspective of overall requirement, functional requirement, database requirementand non-function requirement in the way of constructing models, using cases andholding working meetings were analyzed.(3) According to the system requirements, the architecture and individual functionmodules of the system were developed based on management of water and rainfall data,pre-alarming and forecasting model and technology of WebGIS. Three steps wereimplemented in system for flash flood warning and forecasting. Firstly the water leveland rainfall data were collected from related water and rainfall monitoring stations.Secondly, pre-alarming information was produced by warning and forecasting model. Finally, real-time monitoring of water and rainfall situations was achieved. During theprocess of real-time monitoring of water and rainfall situations, when water level orrainfall data reaches or exceeds the threshold, the system will automatically alarm, andthe warning information will then be timely delivered to persons responsible for flashflood control and residents at danger zone. The functions unitive management of basicinformation, water level and rainfall data and project conditions, real-time monitoring,early warning and emergency response were realized in the prevention system. Theinterfaces of monitoring and warning devices that can be connected with the water andrainfall remote monitoring stations and mobile terminals were provided.