Growing threat of intense tropical cyclones to East Asia over the period 1977-2010

The threat of intense tropical cyclones (TCs) to East Asia has increased in recent decades. Integrated analyses of five available TC data sets for the period 1977-2010 revealed that the growing threat of TCs primarily results from the significant shift that the spatial positions of the maximum intensity of TCs moved closer to East Asian coastlines from Vietnam to Japan. This shift incurs a robust increase in landfall intensity over east China, Korea and Japan. In contrast, an increase of TC genesis frequency over the northern part of the South China Sea leads to a reduction in the maximum TC intensity before landfall, because of their short lifetime; thus, there are no clear tendencies in the landfall intensity across Vietnam, south China and Taiwan. All changes are related to the strengthening of the Pacific Walker circulation, closely linked with the recent manifestation that the warming trend of sea surface temperature in the tropical western Pacific is much higher than that in the central to eastern Pacific.