A process-based assessment of the sea-level rise in the northwestern Pacific marginal seas

Because regional sea-level rise can threaten coastal communities, understanding and quantifying the underlying process contributing to reginal sea-level budget are essential. Here, we assessed whether the regional sea-level rise on the northwestern Pacific marginal seas can be closed with a combination of observations and ocean reanalyses over 1993–2017, as well as with independent observations from in situ profiles including Argo floats and satellite gravity measurements since 2003. The assessment represents that the major contributions come from the land ice melt and sterodynamic components, while the spatial pattern and interannual variability are dominated by sterodynamic effect. The observation-based estimate further shows that along continental shelves, sterodynamic sea-level changes are substantially induced by ocean mass redistribution due to changes in ocean circulation. This result highlights the ocean mass change between the deep ocean and shallow marginal seas, which plays a role in driving regional sea-level rise and variability.