Gradually Cooling of the Yellow Sea Warm Current Driven by Tropical Pacific Subsurface Water Temperature Changes Over the Past 5 kyr.

The integrated effects of ocean‐atmosphere dynamics on the temperature evolution in the western North Pacific marginal seas have remained elusive. In order to study mechanisms controlling southern Yellow Sea (YS) temperature changes, bottom water temperature (BWT) changes were reconstructed for the last 8.8 kyr by using the TEXL86 index, which archives temperature signal of the winter season Yellow Sea Warm Current. Our results reveal a series of abrupt multi‐centennial to millennial scale BWT changes (∼1°C), superimposed on a gradual long‐term cooling (>3°C) trend starting from ∼5 ka to the present. The YS BWT changes are positively correlated with subsurface water temperature changes in the Western Pacific Warm Pool (WPWP). The Western Pacific Warm Pool subsurface water cooling signal was most likely transmitted by the Kuroshio Current into the southern YS, highlighting the role of WPWP in influencing thermodynamics of the extratropical regions during the Holocene. Plain Language Summary: The Yellow Sea (YS) is a semi‐closed marginal sea located in the northwestern Pacific Ocean. During the winter season, the Yellow Sea Warm Current (YSWC) is driven by northwesterly winds, flowing into the southern YS along the west flank of the central trough. The YSWC, a continuation of the Kuroshio Current, brings warm equatorial Pacific water into the YS, leading to milder winters in the surrounding coastal cities compared with other cities on the same latitude in China. The YSWC is sensitive to changes in ocean‐atmosphere dynamics. However, its evolution during the Holocene is not well understood. We reconstruct the winter season temperature changes of the YSWC during the last 8.8 kyr. We found warm temperatures during the mid‐Holocene (8.8‐5 ka) and a gradual cooling trend over the last 5 kyr, which coincides with subsurface water temperature changes in the Western Pacific Warm Pool (WPWP). We suggest that the tropical subsurface water temperature changes of the WPWP are most likely transmitted via the Kuroshio Current into the YS. Our results shed new light on our understanding of the role played by the WPWP water masses in regulating subtropical ocean dynamics and climate during the mid‐to‐late Holocene. Key Points: The temperature evolution of the winter season Yellow Sea Warm Current was reconstructed over the past 8.8 kyrAbrupt multi‐centennial to millennial scale changes are superimposed on a gradual cooling trend starting from ∼5 ka to the presentWestern Pacific Warm Pool subsurface water cooling signal was transmitted by the Kuroshio Current into the southern Yellow Sea [ABSTRACT FROM AUTHOR]