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The palaeoceanographic studies are largely limited by poor carbonate preservation in high-latitude regions. To improve our knowledge in this key area, we studied a sediment core (ANT32-RA05C) in terms of paleomagnetic and 230Th dating and geochemical properties, collected from the continental slope of the Ross Sea, Antarctica. The two major results are as follows: 1) the sedimentation rate based on 230Th isotopes is 1.37 cm/kyr, agreeing well with the correlation of the relative paleomagnetic intensity of the core ANT32-RA05C to changes in Earth’s magnetic intensity and 2) the sediments contain ice-rafted debris (IRD) over 30%, with a considerable contribution of siliceous deposits. Integrating geochronological and geochemical properties of the studied core, a correlation of the regional paleoenvironmental process to the EPICA Dome C (EDC) Antarctic temperature is established, inferring that the IRD input and primary productivity are both enhanced in a warm climate. Moreover, a leading phase of biogenic processes to changes in the ice sheet in the Ross Ice Shelf is observed, highlighting a dominant role of the oceanic circulation in the ice-sheet retreat during the last deglaciation. Overall, the sedimentary record in the Ross Sea documents some key features of the paleoenvironmental processes in the Late Pleistocene, which could be correlated with large-scale changes in Antarctica and thus are worthy of further investigation in the future.

The North Pacific subtropical gyre (NPSTG) redistributes heat and moisture between low and high latitudes and plays a key role in modulating the global climate change and ecosystem. Recent evidence suggests intensification and poleward shift of the subtropical gyres over the last decades due to global warming, but insufficient observations have hampered insight into the integrated effects of ocean-atmosphere interactions at longer timescales. Here we present the first high-resolution (∼12 years) grain-size record from Core CF1 in the Okinawa Trough, western subtropical North Pacific, to reconstruct the evolution of the western boundary Kuroshio Current (KC) of NPSTG during the Late Holocene. Our results indicate the KC slow-down during 4.6–2.0 ka, followed by quick enhancement after 2.0 ka, with centennial-scale variabilities (500–700 years) superimposed on the long-term trend. Over millennial timescales, gradually increased pole-to-equator thermal gradient, due to orbital forcing mechanisms, resulted in long-term enhanced KC, whereas solar activity triggered phase changes in the tropical Pacific mean state and controlled KC anomalies on centennial timescales. We suggest that both forcing mechanisms resulted in ocean-atmosphere feedback provoking concurrent changes in mid-latitude westerly and subtropical easterly winds over the North Pacific, alternating their dominance as source regions causing the dynamic changes of KC at different timescales. Our findings offer insight into the role of external forcing mechanisms in the NPSTG changes before the Anthropocene, which have profound implications for the deeper understanding of changes in ocean gyres under global warming scenarios.