Title : Extreme rainfall induced by Typhoon Yagi-2024 at Hainan and Vietnam, and critical assessments of storm impact before and after rainfall
Abstract:
The Marine typhoon Yagi occurred in 2024 both in Hainan and Vietnam producing intense ecological debris over seven days mainly exhibiting rainfall in several locations (3) most notably Vietnam and the Hainan land area. While severe active storms are known to cause damage to a number of local facilities, the focal point of this work on typhoon behavior aims to strategically perform complex mathematical projections on baseline rainfall patterns of the impact through enthalpy flux (EF) and Moisture flux (MF) activities. This data indicates the speed, locality, and volume of both issues within the study area, and with high results at the time of landfall many concerns on the typhoons intensification and evolution suggest it's most damaging period between landfall in the region(s).
Data managed to constrain landing results to a positive and negative pattern from circulation prior to Hainan impacts, latent heat flux (LHF) recovered at 600 W/m2and sensible heat flux (SHF) recorded at 80 W/m2. In the second stage the values of LHF and SHF (When landfall occurred) were increased and at 700 W/m2 and 100 W/m2, respectively due to circulation changes. Geographically, the Vietnam area exhibits unique topographic sections leading a more intense rainfall observational pattern, similarly the LHF measured here shows corresponding results with an elevate Moisture flux (MF) following evaporation increases in addition to heavier rainfall. Yet, the disparities in rainfall density from the Philippines, Hainan, and Vietnam are near active stage conditions such as landfall and passing through Philippines 75 mm on 2 September, Hainan 100 mm on 6 September, Vietnam 95 mm on 7 September (landfall and after). Typhoon movement is unsteady and on these days heavy rainfall was observed typhoon movement can be characterized as non stable. The typhoons signature pattern shows exemplary conditions during landfall in Vietnam based on precise circulation structure, adaptive weather qualities, known as high sea surface temperature (SST) at 30.5 °C and higher, substantial low-level moisture convergence, and rainfall behaviors as determined by enthalpy flux (EF) during occurrences in the Vietnam study area.
