Role of Large-scale Circulation on Tropical Cyclone Landfall in Japan

Using ECMWF reanalysis dataset(ERA-40) and Japan reanalysis dataset(JRA-25) with JMA global analysis dataset up to 2004, we examined the relationship between large-scale circulation and tropical cyclone landfall in Japan. EOF analysis shows that there are two major large-scale atmospheric patterns, one is sub-tropical high pattern and another is ENSO pattern. When we compared the temporal variation of these two modes with the numbers of tropical cyclone landfall in Japan, we recognize that sub-tropical high pattern corresponds well with the numbers of tropical cyclone landfall in Japan, especially less landfall years, such as 1964, 1969, 1973, 1980, 1983, 1987 and 1995. In these years positive height anomalies at 850 hPa over the western North Pacific are evident south of Japan, which prevent tropical cyclone approach to Japan. However, negative height anomalous year does not correspond well with more tropical cyclone landfall in Japan. This result confirms the result by Harr and Elsberry(1995). It is also shown that ENSO pattern does not influence the number of tropical cyclone landfall in Japan.