专家简介：

Chung-Hsiung Sui received a bachelor's degree from National Taiwan University (NTU) in 1976, and a doctorate from the University of California at Los Angeles (UCLA) in 1984, both in Atmospheric Sciences. He was a Postdoctoral Fellow at UCLA and the University of Maryland, a research scientist at Goddard Space Flight Center (GSFC) of NASA during 1985-2001. Since 2001, he returned to Taiwan to work first in National Central University (NCU) and then in NTU where he is a distinguished professor in Department of Atmospheric Sciences. He was a visiting faculty member at the University of Tokyo, Japan, and National Center for Environment Prediction during sabbatical leaves, and visited various academic institutions to present seminars and invited lectures. He was an organizer of the University Allied Workshop to arrange annual meetings for graduate students and young researchers from Japan, Korea, Taiwan, and China to promote climate research and modeling, and to cultivate collaborations among future leaders in climate science.

His research interest covers a wide range of topics in tropical Meteorology, climate dynamics, and hydro-climate processes. He published over 100 papers (with 7134 citations and h-index 42 in Google Scholar) on subjects including climate equilibrium study, tropical convective responses to radiative and microphysical processes, diurnal cycle, cloud clustering and associated cloud microphysical processes, precipitation efficiency, air-sea exchanges and ocean mixing processes, intraseasonal and interannual variability in Indo-Pacific climate system, and influences of climate oscillations on synoptic disturbances, convection coupled equatorial waves, and rainfall in East Asian monsoon.

His research accomplishments won him various recognitions including Fellow of Meteorological Society of the ROC, distinguished Professor of NCU and NTU, Academic Summit Program funded by Ministry of Science and Technology, Outstanding Scholar Award by the Foundation for The Advancement of Outstanding Scholarship, GSFC Center of Excellence Award, and various scientific awards in Laboratory for Atmospheres, NASA/GSFC.

报告摘要：

We examine the evolutions of “single-year” and “multi-year” El Niño events by analyzing observed and simulated long-term data. The distinct features that contrast the single-year and multi-year El Niño episodes include: onset timing, the strength during the growing-mature stage, the center of warm SST in the mature stage, and oceanic upwelling Kelvin waves during the decay stage. The upwelling Kelvin waves rapidly reverses the equatorial zonal current anomalies from eastward to westward with its geostrophic component, and cause cold advection with the climatological zonal SST gradient in the single-year El Niño. Conversely, the eastward equatorial zonal current anomalies continue, and maintain the warm zonal advection in the multi-year events together with the lasting oceanic subsurface heat content. The contrasting oceanic processes are quantified by forced responses from an ocean model at different stages. The effect of later or earlier El Niño onset is examined by atmospheric GCM-slab ocean model (AGCM-SOM) experiments. The early developing El Niño is shown to induce the remote WNP and IO responses to drive the WP easterly winds during the mature winter compared to the late developing El Niño. Finally, the fully coupled experiments further emphasize the role of WNP feedbacks, as the tropical WP easterly winds vanish and the El Niño-to-La Niña phase transition is aborted when the air-sea interaction is artificially suppressed over the North Pacific in a case study.