Risk assessment and analysis of ice disaster in Ning–Meng reach of Yellow River based on a two-phased intelligent model under grey information environment

Ice disaster is serious in Ning–Meng reach of Yellow River in China. Due to the complexity of ice disaster, it usually presents grey uncertainty. In order to evaluate the probability of ice disaster loss caused by the adverse events and reveal the development between ice regime data and ice disaster risk under grey information environment, this paper assesses and analyzes the ice disaster risk in Ning–Meng reach of Yellow River. Firstly, the index system of ice disaster risk is established based on the formation mechanism of ice disaster and the novel features of ice regime presented in recent years. Then, the two-phased intelligent model under grey information environment is proposed. The risk degree of ice disaster is assessed with grey interval relational clustering at the first phase, and the decision rules that reflect the development between ice regime information and ice disaster risk degree are extracted with grey dominance-based rough set approach at the second phase. The last empirical analysis of ice disaster risk in the year of 1996–2015 shows that the evaluated ice disaster risk degree of different years is consistent with the practical ice regime characteristics and the extracted decision rules could do as the intuitive criterion to estimate the ice disaster risk through ice regime data.