INVERSE DETERMINATION OF SURFACE HEAT-FLUX OVER THE YELLOW SEA IN WINTER 1986 FROM SEA-SURFACE TEMPERATURE DATA

An assimilation of routine sea surface temperature observations is con ducted to estimate the sea surface heat flux in the Yellow Sea during the winter of 1986. Ten-day mean SST compilations, published by the Ja pan Meteorological Agency, are used. The time window is from 0000 Japa n Local Time (JLT) 21 January to 0000 JLT 21 February 1986. Because th ere are only three frames of the observed temperature available for th e time window, only a steady-state distribution of the heat flux is de termined. A tonguelike feature of the optimized hear flux distribution is consistent with the warm SST anomaly at the center of the Yellow S ea trough. The optimized heat flux generates improved simulation of th e cooling trend of the temperature time series. The variational method is the assimilation procedure employed. The developed scheme is able to optimize simultaneously the initial temperature condition and the s ea surface heat flux without a priori knowledge of either. A coarse-re solution Hessian is used to evaluate errors of the assimilation.