基于信息扩散理论的天津旱涝灾害危险性评估

Drought and Waterlogging Hazard Assessment in Tianjin Based on Information Diffusion Model

采用基于信息扩散理论的评估模型、应用天津近22年的旱涝指数为样本,对天津旱涝危险性进行评估,给出了天津旱涝指数概率密度曲线及不同程度旱涝危害发生的可能性。结果表明,重旱、重涝几乎不可能发生;大旱发生的可能性也很小——约700多年一遇;偏旱、大涝、偏涝这3种强度的灾害则比较频发,年发生概率分别为0.231 3、0.159 1、0.073 4。评估结果与天津近22年的实际情况基本吻合,说明应用此模型,对信息量不足的自然灾害进行危险性评估是可行的。

Using waterlogging indexes of recent 22 years as samples, the drought and waterlogging hazards in Tianjin are assessed by adopting the information diffusion theory based assessment model. The probability density curves of the drought and waterlogging indexes and probability of drought and waterlogging of different degrees in Tianjin are given. The results show that occurrence of severe drought and vast waterlogging is impossible in Tianjin. There is little possibility of occurrence of great drought in Tianjin, once in about 700 years. The partial drought, severe waterlogging and partial waterlogging occur frequently. Their annual possibilities are 0. 2313, 0. 1591 and 0. 0734 respectively. This result basically coincides with the actual condition of Tianjin in recent 22 years. It indicates feasible to make risk assessment of natural disaster without enough information by using this model.