SIMULATION OF TROPICAL CYCLONES OVER THE WESTERN NORTH PACIFIC AND LANDFALLINGIN CHINA BY REGCM4

This study evaluates the performance of the regional climate model RegCM4 in simulating tropical cyclone(TC) activities over the Western North Pacific(WNP) and their landfalling in China. The model is driven by ERA-Interim boundary conditions at a grid spacing of 25 km, with the simulation period as 1991-2010. Results show that RegCM4 performs well in capturing the main structural features of observed TCs, and in simulating the genesis number and annual cycle of the genesis. The model reproduces the general pattern of the observed TC tracks and occurrence frequency. However, significant underestimation of the occurrence frequency as well as the TC intensity is found. Number of the landfalling TCs over China is also much smaller than that of the observed. Bias of the model in reproducing the large-scale circulation pattern and steering flow may contribute to the underestimated landfalling TC numbers.