Recent cooling trend in the Yellow and East China Sea

Abstract

The Yellow and East China Seas (YECS) are widely believed to have experienced a robust warming since the 1980s. However, after the warming reached its peak in the late 1990s, the sea surface temperature (SST) reveals a basin scale cooling trend in the YECS. To understand the mechanism of the decadal transition in the YECS SST, this study investigates its relationship with the large-scale climate variability around the YECS by using a basin mode of YECS SST estimated from the optimum interpolation SST (OISST) for 33 years (1982&#8722 2014). The principal component (PC) of a basin mode in the YECS varies coherently with the Pacific Decadal Oscillation (PDO) before the late 1990s however, the correlation between the PC and the PDO dramatically decreases to an insignificant level after the late 1990s, indicating a potential regime shift in the dynamical linkage between the YECS and the North Pacific. Instead of the PDO, after the late 1990s, the winter SST in the YECS is more closely associated with the variation of the Siberian High along with its intensification, suggesting that the intensified SH pressure system in recent decades has played an increasing role in determining the states of the YECS.rend in the YECS. To understand the mechanism of the decadal transition in the YECS SST, this study investigates its relationship with the large-scale climate variability around the YECS by using a basin mode of YECS SST estimated from the optimum interpolation SST (OISST) for 33 years (1982&#8722 2014). The principal component (PC) of a basin mode in the YECS varies coherently with the Pacific Decadal Oscillation (PDO) before the late 1990s however, the correlation between the PC and the PDO dramatically decreases to an insignificant level after the late 1990s, indicating a potential regime shift in the dynamical linkage between the YECS and the North Pacific. Instead of the PDO, after the late 1990s, the winter SST in the YECS is more closely associated with the variation of the Siberian High along with its intensification, suggesting that the intensified SH pressure system in recent decades has played an increasing role in determining the states of the YECS.