Long-term changes of cross-shelf transports in the Yellow and East China Seas under different greenhouse gases emission scenarios

The cross-shelf exchange between the Yellow and East China Seas (YECS) with the Kuroshio is important for vorticity, freshwater, and effluence balances of the regional and global oceans, the responses of which to future climate changes are estimated based on Max-Planck coupled model simulations under one historical (20C, 1970–2005) and two representative concentration pathway scenarios of global warming (RCP4.5 and RCP8.5) from 2006 to 2099. The results of the 20C simulation have shown prominent cross-shelf transports in the YECS, with annual mean outflow (OVT) and inflow (IVT) volume transports across the 100 m isobath of 3.97 Sv and 2.86 Sv (1 Sv = 106 m3 s−1), respectively. These annual mean OVTs (and their equivalent IVTs) are projected to increase by 0.42 Sv and 0.48 Sv from 2006 to 2099, at rates of 11.0% and 12.8% from the 2006–2016 means, under the RCP4.5 and RCP8.5 scenarios, respectively. The maximum rates of increase are found in winter to be at 13.2% and 19.9%, respectively. Analyses suggest that the winter monsoon has a long-term southwesterly change, forcing coastal currents to flow into the Yellow Sea along the China coasts to compensate for the increase of the southeastward surface Ekman transport. Due to increases of the Tsushima Strait and upper-layer Kuroshio transports, both the OVT and IVT across the 200 m isobath have onshore changes, resulting in net onshore transport increments of 0.30 Sv and 0.57 Sv under the RCP4.5 and RCP8.5 scenarios, respectively. The enhanced cross-shelf exchanges under future warming scenarios in the YECS suggest their potential importance in carbon transportation and storage.