A Numerical Simulation of Long-Term Sea Level Change in the East Asian Marginal Seas

Abstract

To investigate the regional sea level rise (SLR) and its possible mechanisms in the East Asian Marginal Seas (Yellow Sea (YS), East China Sea (ECS) and Japan/East Sea (JES)) sea level variation was simulated using the global ocean-sea ice coupled model (GFDL MOM5-SIS) forced with European Centre for Medium-range Weather Forecasts reanalysis data for 58 years (1958-2015). Seasonal variation in the simulated sea level shows comparable amplitude and phase to those of the satellite altimetry for 1993-2014 in each sea region. Rates of the simulated SLR are compared with those of the reconstructed sea level (Hamlington et al., 2011) and satellite altimetry sea level: rates of SLR in the YS, ECS and JES for 1958-2009 are 2.1 mm/yr, 2.6 mm/yr, 2.1 mm/yr in the model, and 2.2 mm/yr, 1.9 mm/yr, 2.2 mm/yr in the reconstructed sea level, respectively. For 1993-2014, the SLR rates in the YS, ECS and JES are 3.8 mm/yr, 4.1 mm/yr, 2.8 mm/yr in the model, and 3.4 mm/yr, 2.6 mm/yr, 3.1 mm/yr in the satellite altimetry sea level, respectively. The regional mean sea level distribution in the model shows the SLR of 2 similar to 5 cm for 2005 to 2014 relative to the period of 1993 to 2002, which is also evident in the satellite altimetry sea level but in more localized areas. In the SLR between those two periods, model simulation reveals that non-steric sea level change was dominant in the YS, ECS and JES, which is different from the Kuroshio region where steric component was dominant This result suggests that the recent SLR in the East Asian Marginal Seas is mainly driven by the mass convergence such as the transport changes in the shelf area.