Researching the Variation of Typhoon Intensities Under Climate Change in Vietnam: A Case Study of Typhoon Lekima, 2007

Abstract

Most of the typhoons that impact coastal regions of Vietnam occur from the north to the central part, between June and November. As a result of global warming, typhoon intensities are expected to increase. Therefore, an assessment of various typhoon strengths is essential. In this study, Typhoon Lekima, which hit Vietnam in 2007, was simulated by weather research and forecast models, using ensemble simulation methodology. Reproductive results of the typhoon intensity are similar to actual estimated values from the Japan Meteorological Agency. Also, the variation of typhoon intensities and heavy rainfall in future climate scenarios was investigated using numerical simulations based on pseudo global warming conditions, constructed using fifth-phase results of the Coupled Model Intercomparison Project multi-model global warming experiments. Simulation results of five Pseudo Global Warming (PGW_FF) models indicate that intensities of the typhoon will be magnified in future climate. The minimum sea level pressure of typhoons similar to Typhoon Lekima in the future will increase from 8 hPa to 9 hPa, and the spatial distribution of maximum wind speed and tracked direction will move towards the southern regions. Total precipitation will significantly increase for a maximum of six hours, and the spatial distribution of heavy rain caused by typhoons will shift from the north to the southwest of Vietnam. In the future, simulated results showed that global warming correlates strongly with a significant increase in typhoon intensity and heavy rain.