Storm Surge Hindcast and Return Period of a Haiyan-Like Super Typhoon

Abstract

The extremely intense Typhoon Haiyan (local name Yolanda), struck the Philippines in November 2013, catastrophically impacting the region. It is important to understand the storm surge characteristics and occurrence probability of such super typhoons for reconstruction of the devastated area. This study mainly examines two topics. First, the characteristics of Typhoon Haiyan and its related storm surge were analyzed with a series of numerical experiments using an empirical typhoon model and storm surge model. The maximum surge height and inundation area were estimated and validated against measurements of tides and wind speeds obtained from local agencies NAMRIA and PAGASA, as well as against post-event surveys of maximum inundation heights. Based on the analysis of best hindcast results, the maximum storm surge level was about 5 m at Tacloban on Leyte Island. Second, the return period of a Haiyan-like typhoon and associated storm surge was estimated with NOAA's long-term observed IBTrACS typhoon dataset and a stochastic tropical cyclone model. Statistical analysis of typhoons around Tacloban was performed, and the estimated return period of storm surge levels seen during Typhoon Haiyan is 240–360 years.