Changes of tropical cyclone landfalls in South China throughout the twenty-first century

摘要

The nested regional climate/mesoscale modelling system developed by the authors is applied to the Hadley Centre Global Environment Model version 2-Earth System global model outputs to project future changes of landfalling tropical cyclone (TC) activity in the South China region. Results show that the modelling system is capable of reproducing the current TC landfall climatology, although it exhibits a noticeable southward bias of TC activity of in the western North Pacific. Future projections show a continuous northward migration of TC activity in the western North Pacific throughout the twenty-first century. Fewer TCs making landfall in South China are projected in the late century, but these landfalling TCs tend to be more intense. Investigations in the large-scale environment suggest that despite warmer sea surface temperature and weaker vertical wind shear, the drier and less cyclonic lower atmosphere all-season is responsible for the reduced TC activity. However, once a TC is formed, the environment it stays in is as wet as today and so it can intensify further than the present-day TCs. Inter-annual variability is also explored, and the influence of the ENSO variation appears to be smaller.