미래기후조건에 대한 동해의 반응에 관한 수치 실험

Abstract

Response of the East (Japan) Sea to the climate change scenario has been investigated using a simplified 2-D global ocean model and a 3-D regional ocean model. Transport change of the East Asian Marginal Seas (EAMS) driven by the GFDL CM 2.1 predicted wind stresses computed under the IPCC A1B scenario has been analyzed and compared with the solution forced by the present wind stresses. The annual mean transports in the various straits in the EAMS such as Luson St., Taiwan St. and even Kuroshio Current transport generally decrease. But it is interesting that the East Sea Throughflow (EST) comes from the Korea St. and drains out of Tsugaru and Soya Straits has increased slightly. It is noteworthy that most of the wind driven transport change is shown conversely depending on the season. Generally, the volume transports in the EAMS increase in winter and decrease in summer except for the Kuroshio Current calculated at the south of Japan whose transport decreases regardless of season. Though the annual mean transport change trend is different from other strait transports, EST also shows that the winter transport increases while the summer transport decreases. To understand the influence of the future climate change to the East Sea, we have estimated the future EST by applying transport variability described above to the present state of EST. This is used as future lateral inflow/outflow at the four straits of the East Sea connecting to the Pacific Ocean. The surface boundary conditions of the future state are also adopted from the GFDL CM 2.1 solution. The future East Sea solution is compared with the present state solution in terms of upper ocean heat transport and meridional overturning strength change.