MS Thesis Defense: Wenjing Liu

The UNC-CH Department of Marine Sciences and UNC’s Institute of Marine Sciences (IMS) presents the Master’s Thesis Defense of graduate student, Wenjing Liu. This event will be held on Tuesday, April 28th, at 1:30 pm. This event will be held ONLINE ONLY and it will be available online via Zoom (Meeting ID: 950-8384-1255).

Seminar Title: Diversity of the Pacific-Japan pattern and its influences on Northwest Pacific tropical cyclone activity

Abstract: The Pacific-Japan (PJ) pattern features a meridional dipole pattern of atmospheric circulation between the tropical and midlatitude Northwest Pacific. Using observations and large-ensemble atmospheric simulations, our study shows that the PJ pattern has experienced distinct changes in its property and forcing mechanism from the period 1976-1988 to 1991-2010, with the source of forcing shifting from the tropical Indian Ocean to the tropical western-central Pacific Ocean. These changes are tied to changes in the characteristics of El Nino-Southern Oscillation (ENSO), i.e., shifting from a combination of various types of ENSO to a dominance of central-Pacific ENSO, leading to reduced and increased sea surface temperature variance respectively in the abovementioned two regions. Further analysis suggests that the PJ pattern of 1976-1988 in observations may reflect a choice of nature out of two options. Lastly, the thesis shows that different types of PJ pattern affect Northwest Pacific tropical cyclones differently, particularly their genesis.