Abstract

The proportion of intense tropical cyclones (Category 4 and 5 on the Saffir-Simpson scale) has increased. It is demonstrated that the increase of the proportion of intense typhoonsduring 1980-2015 is consistent with the corresponding changes in the ocean/atmosphere environment. The deepening of the ocean mixed layer resulting from the temporal variations and track shifts plays a dominant role in the observed increase of the proportion of intense typhoons. The annual mean latitude where tropical cyclones (TCs) reach their lifetime maximum intensity (LMI) over the western North Pacific basin (WNP) has shifted northward since the early 1980s and it is suggested that the shift is due to the northward migration of the mean TC formation location. It is suggested that the observed poleward trend in the mean latitude of LMI is physically consistent with changes in the large-scale ocean/atmosphere environment and TC track. This study also demonstrates that the temporal change in the environmental parameters has little influence on the observed shift of the mean LMI latitude. The poleward migration of the mean LMI latitude is mainly due to the TC track shift, which results primarily from the change in the large-scale steering flow.

Presenter Profile

Dr. Liguang Wu, a professor and Ph.D. supervisor of Fudan University. He got his bachelor degree from department of meteorology of Nanjing University and master degree from National Marine Environmental Forecasting Center, Ph.D. from University of Hawaii. He has long been engaged in research related to tropical cyclones, including tropical cyclone generation, movement, intensity structure change mechanism, tropical cyclone activity climate change, and tropical cyclone seasonal forecast. During his work at NASA and the University of Maryland, he has led three NASA tropical cyclone research projects. After returning to China in 2008, he has presided over and participated in the National Program on Key Basic Research Projects (973 Program), the Ministry of Science and Technology Industry Research, the Key Projects and General Projects of National Natural Science Foundation of China. He has served as an editor and reviewer of academic journals domestic and abroad, and has published more than 100 research papers.