To examine the evolution of the wind‐driven flows in the Yellow Sea (YS) during winter, ocean circulation was simulated using a three‐dimensional ocean model with realistic topography and atmospheric forcing. The simulated sea surface temperature, ocean currents, and path of the Yellow Sea Warm Current (YSWC) agreed with observations. Southward currents along the Korean coast and the Chinese coast in winter were also effectively identified. Spectra of the daily mean winds and the YSWC velocities in the subsurface layer had dominant peaks at 12 and 20 day periods. Time‐lagged correlation analysis suggested that the downwind flow in the surface layer reacts concurrently to the northwesterly wind in winter whereas the subsurface layer responds with a delay. One day after the wind burst, an upwind current in the subsurface layer appeared in the center of the trough, whereas the downwind flow in the surface layer decreased significantly. Two days later, the upwind flow in the subsurface layer shifted to the west of the trough while the downwind flow along the Korean coast strengthened. These flow responses to the wind variations resulted in a clockwise circulation in the YS during winter.

This study presents future climate change projections in the Northwest Pacific (NWP) marginal seas using dynamic downscaling from global climate models (GCMs). A regional climate model (RCM) for the Northwest Pacific Ocean was setup and integrated over the period from 2001 to 2100. The model used forcing fields from three different GCM simulations to downscale the effect of global climate change. MIROC, ECHAM, and HADCM were selected to provide climate change signals for the RCM. These signals were calculated from the GCMs using Cyclostationary Empirical Orthogonal Function analysis and added to the present lateral open boundary and the surface forcing. The RCM was validated by comparing hindcast result with the observation. It was able to project detailed regional climate change processes that GCMs were not able to resolve. A relatively large increases of water temperature were found in the marginal seas. However, only a marginal change was found along the Kuroshio path. Heat supply to the atmosphere decreases in most study areas due to a slower warming of the sea surface compared to the atmosphere. The RCM projection suggests that the temperature of the Yellow Sea Bottom Cold Water will gradually increase by 2100. Volume transports through major straits except the Taiwan Strait in the marginal seas are projected to increase slightly in future. Increased northeasterly wind stress in the East China Sea may also result in the transport change.