Typhoon hazard analysis based on the probability density evolution theory.

In this article, a new typhoon hazard analysis method is presented by introducing the probability density evolution theory. In the suggested method, the randomness in the typhoon occurrence is represented by the combination of a homogeneous Poisson process and a joint probability density function for both the typhoon genesis time and the genesis position. Then a set of physical models, including a typhoon intensity model, a typhoon track model and a boundary layer wind field model, is introduced to describe the typhoon process. The typhoon intensity model with high efficiency is used to simulate the evolution of typhoon intensity given the environmental variables. The typhoon motion is simulated by the beta-advection model where the steering flow is the linear combination of the large-scale flows at 850 hPa and 250 hPa, and the beta drift is solved from the non-divergent barotropic vorticity equation. At last, the typhoon induced surface wind at the interested engineering site is calculated with the help of a three-dimensional non-linear boundary layer wind field model. On the basis of the above physical models, the generalized density evolution equation is adopted to solve the probability distribution of the annual maximum typhoon surface wind speeds. The typhoon surface wind speeds associated with specified recurrence intervals are estimated consequently. As an example, the typhoon hazard at ten selected cities on the southeast coast of China is assessed. The surface wind records from the observation stations are collected to estimate the cumulative distribution function of the annual maximum wind and are compared to the analyzed results. The good comparison between the historical records and the analyzed results demonstrates the adequacy of the proposed method. • Physical models are used to generate the synthetic history of typhoon. • The probability density evolution theory is used to investigate the propagation of randomness. • The proposed method is used to assess the typhoon hazard of several cities on the southeast coast of China. [ABSTRACT FROM AUTHOR]