2.4. Flood Probability Analysis
Statistical analysis is performed on the generated storm tides for
locations/stations at 1000-m intervals along the Shanghai coast. The
probability of storm tide events can be estimated by extreme value
models such as generalized extreme value distribution family. In this
study, the Generalized Pareto Distribution (GPD) is applied to describe
the limiting behavior of maximum storm tide values for all individual
events using a Peaks-Over-Threshold approach (Simiu and Heckert 1996)
and the maximum likelihood method (Lin et al., 2012). The GPD threshold
is determined by trial to ensure that the smallest error in the
distribution is obtained (Marsooli et al., 2019). Then, the return
periods of peak storm time levels are calculated by assuming that the
storm arrival for the region is a stationary Poisson process (Lin et
al., 2012).