Typhoon track simulations in the North West Pacific: Informing a new wind map for Vietnam

Abstract

This paper addresses the need to revise the current Vietnamese design wind map by proposing a new typhoon wind map for the country, based on Monte Carlo simulations of typhoon tracks in the North West Pacific basin. Using historical typhoon data from the period 1951 to 2019 provided by the Japanese Meteorology Agency, novel multi-variate regression models are proposed for typhoon translation and intensity. Simulations are performed for a 10 ​000 year period and 1-in-50 year extreme wind speeds at gradient height are estimated to create the proposed typhoon wind map. The proposed simulation method is validated by comparison with existing wind codes for China and Hong Kong, and with other simulations and modelling in the literature. The design wind speeds obtained from the current simulations compare well with the Chinese (differences in the range 0%–14%) and Hong Kong (less than 5%) code predictions for various cities in China. While the proposed wind map with a finer geographic granularity agrees well with the current Vietnamese wind code for most areas affected by typhoons, there are notable differences for areas subjected to the strongest typhoon winds, emphasising the need for a revision of the code.