His research focused on including surface exchange coefficients Cd/Ck in the control variables of 4-dimensional variational data assimilation. In this way, he could estimate these crucial model parameters for Tropical Cyclone evolution, and improved Tropical Cyclone analyses both in an idealized experiment and in a real Typhoon case. Estimating key model parameters is one of the frontier research topics, and it was very interesting to see his pioneering work.
