第八届青年地学论坛

Based on a suite of well-dated sediment cores in the western Pacific margin, this work aims to analyze alkenone (U37K' ) sea surface temperature (SST) signals and investigate the changes in the Kuroshio Current (KC) strength during the past 7,000 years. In brief, decadally-resolved SST record on the pathway of the Yellow Sea Warm Current (YSWC), a downstream branch of the KC, along with coastal SSTs outside of the YSWC effect, demonstrate a remarkably enhanced YSWC, and thereby the KC, during the cool interval between 1,400–1,850 AD (the Little Ice Age, LIA). Besides this observation on multi-centennial timescales, collection of independent SST reconstructions along the Okinawa Though also effectively indicates a considerable intensification of the KC since ~3,000–4,000 years ago. Such patterns, together with other paleorecords under the influence of eastern Pacific boundary currents, namely the California Current (CC) and Alaska Current (AC), signify a strengthened North Pacific Subtropical Gyre (NPSG) circulation during the late Holocene. As more (less) El Niño events were believed to occur in the eastern Pacific during the late Holocene (LIA), it appears that the NPSG enhancement should have resulted from long-term southward migration of the Intertropical Convergence Zone (ITCZ). Considering the role that NPSG circulation plays in transferring heat content from the Western Pacific Warm Pool toward the mid- to high-latitude North Pacific, identified NPSG changes thus have significantly regulated the basin-scale ocean-atmosphere interactions. In this sense, an in-depth investigation of future NPSG regime, dependent upon anthropogenically-forced ITCZ shift and concurrent El Niño activity, deserves more effort to confidently project the basin-scale climate and its far-reaching impacts.

黄海暖流；中晚全新世,黑潮,太平洋环流圈