A MESOSCALE HEAT BUDGET ANALYSIS DURING TYPHOON PASSAGES AROUND THE SETO INLAND SEA, JAPAN

Abstract

 We investigate with a detailed downscaling oceanic model on impacts of typhoon passages on upper-ocean cooling in and around the Seto Inland Sea, the largest semi-enclosed estuary in Japan. A sea surface heat budget analysis is conducted using the heat balance equation based on the outcomes of the innermost ROMS-L2 model results. After the mid September, the net heat flux at surface becomes negative to induce prominent surface cooling and cold-water formation in the upper ocean. The surface heat flux verying with the typhoons are characterized by decrease of short wave (solar) radiation and negative latent heat flux enhanced by strong surface wind stress and unstable condition of the lower atmospheric boundary layer during the typhoon passages. The latent heat flux is also strengthened by abrupt decrease of the near-surface atmospheric specific humidity after the typhoon passages.