Cooperative Institute for Research in the Atmosphere

Long-term variation of TC lifetime maximum intensity location over the northwestern Pacific

The annual mean locations of tropical cyclone (TC) lifetime maximum intensity (LMI)have been poleward migration for the last 40 years. In this study, we evaluated the factors affecting the long-term changes in the LMI location using the track pattern classification metrics. We classified the TCs in the western North Pacific into seven clusters by the Fuzzy c-mean clustering. Using the track patterns, we calculated the effects of track pattern change and pure change in the total variation of LMI latitudes. As a result, the long-term poleward migration of the LMI latitudes is associated with the pure change rather than track change. Also, the result indicated that the long-term change in the pure change is strongly associated with the local sea surface temperature warming. The track change has a large interannual variation related to the El Nino/Southern Oscillation while it has a minor effect on the long-term changes in the LMI latitudes.