TY - JOUR AU - Tri Thuc Pham AU - Van Manh Dinh AU - Ba Thuy Nguyen PY - 2020/10/09 Y2 - 2024/03/28 TI - Abnormal seawater level rises and warning issues of surges after typhoons landfall time JF - VNUHCM Journal of Engineering and Technology JA - STDJET VL - 3 IS - SI3 SE - Research article DO - https://doi.org/10.32508/stdjet.v3iSpecial%20Is.649 UR - http://stdjet.scienceandtechnology.com.vn/index.php/stdjet/article/view/649 AB - Typhoon surge is the phenomenon of seawater level rises higher than the normal levels (tidal water level) under the combined effect of many factors during typhoons. Along the Vietnam coast, this phenomenon occurred quite often and very dangerous, especially when occurring at the same time with high tide. There are many research projects and publications relative to this problem, such as National projects. This phenomenon caused by strong wind and air pressure depression during typhoon acting therefore often happened before or just during the typhoon landfall. However, statistically, depending on the track and movement speed of the typhoon, the surges sometimes occur several hours after the typhoon landfall time. In this research, the integrated model for surge, wave, and tide during typhoon acting (SuWAT) is applied to simulate sea-level oscillation due to typhoons by two ways: (1) - the wind and air pressure fields are described the analytical model with the typhoon parameters (track, air pressure depression at the typhoon center, max wind speed …) re-analyzed from the observed data and (2) - from the numerical model WRF for weather prediction. With the same calculating domain, grid, open boundary conditions, the calculated results of SuWAT show that the sea level oscillation obtained by using wind and air pressure fields from WRF is better than that by using the analytical model in comparison with the observed data. The main reason for the difference in the calculation of the rising water level is that the WRF has well simulated the post-typhoon circulation combined with the monsoon at the time after the typhoon landfall time. The results of the study will be valuable experiences in alerting and selecting typhoon surge projections for the Northern coastal strip. ER -