Shoichiro Kido is a researcher at the Application Laboratory of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). His research background is in physical oceanography and climate dynamics, with a particular interest in large-scale ocean circulation and ocean–atmosphere interactions. He received his Ph.D. in 2020 from the University of Tokyo.
During his doctoral studies, he investigated the relationship between the Indian Ocean Dipole and upper-ocean salinity variations using a combination of observational data analysis and ocean model experiments. This work focused on understanding how air–sea interaction and ocean circulation processes shape salinity variability and its role in climate variability.
After obtaining his Ph.D., he joined JAMSTEC, where he works on ocean modeling and prediction, contributing to the development and application of high-resolution ocean modeling systems.
Western boundary currents are characterized by strong jets and vigorous mesoscale eddies, which play a crucial role in ocean heat transport, air–sea interaction, and regional climate variability. However, predicting their year-to-year variability remains challenging because it arises from a complex interplay between atmospheric forcing and intrinsic ocean dynamics.
In this lecture, I will present recent progress in predicting the interannual variability of western boundary current jets and eddies using high-resolution ocean models. I will first introduce the motivation and development history of a quasi-global ocean data assimilation and prediction system designed to explicitly resolve mesoscale dynamics. The system combines eddy-resolving resolution with ensemble-based approaches to quantify both predictable and unpredictable components of ocean variability.
Using this framework, I will showcase prediction results that highlight how large-scale atmospheric forcing shapes the low-frequency evolution of western boundary currents, while intrinsic oceanic chaos strongly modulates their spatial structure and amplitude from year to year. I will also discuss how ensemble simulations enable a quantitative separation of forced and intrinsic variability, providing new insights into predictability limits.
Finally, I will focus on recent extreme events in western boundary current regions, demonstrating how high-resolution ensemble modeling helps to interpret their physical origins and assess their predictability. These results underscore the importance of combining advanced data assimilation, ensemble methods, and high-resolution modeling to better understand and predict the highly energetic ocean circulation.