Evaluation of the ocean mid-range prediction performance for the seas around Korea using a numerical model

Abstract

Marine environment in seas around Korea show large seasonal changes since Korea is located in the mid-latitude of the northern hemisphere. Although the importance of the midterm prediction including seasonal changes has emerged recently, studies on mid-term prediction of regional scales are limited. Thus, we established Ocean MId-rAnge prediction System (OMIDAS) for the Northwest Pacific focusing on the seas around Korea. To validate the prediction performance of our model, three-month reforecast experiments were conducted by using atmospheric forcing and open boundary condition from Climate Forecast System version 2 (CFSv2) forecast data. Compared with observation data, the reforecasts tend to overestimate SST, especially in the Kuroshio region in all seasons. The currents of Kuroshio and Oyashio are not well simulated in CFSv2. Seasonal prediction performance is higher in winter and autumn than in spring and summer. This result is expected to be due to the uncertainty of atmospheric forecasting in mid-latitude spring and summer in the open ocean simulated by CFSv2 forecast.