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Turbidity currents regulate the transport of terrigenous sediment, abundant in carbon and nutrients, from the shelf to the deep sea. However, triggers of deep-sea turbidity currents are diverse and remain debatable in individual cases due to few direct measurements and unpredictable occurrence. Here we present long-term monitoring of turbidity currents at a water depth of 2104 m on the margin of the Gaoping Submarine Canyon off Taiwan, which has the world's highest erosion rates and wettest typhoons. The unique 3.5 year record of in situ observations demonstrates the frequent occurrence of deep-sea turbidity currents (an average of six times per year from May 2013 to October 2016), most of which show enhanced sediment flux, raised temperature, and lowered salinity. They are attributed to elevated discharge of the Gaoping River due to typhoons traversing Taiwan. The total duration of these prolonged turbidity currents amounts to 30% of the entire monitoring period, contributing to ~72% of total sediment transport in the lower canyon. Our study demonstrates for the first time that typhoons are the most important triggers, in the long term, of frequent turbidity currents and enhanced sediment delivery into the deep sea in the typhoon-rivercanyon environment.

High‐resolution clay mineral assemblage combined with Nd and Sr isotopic compositions of Core MD12‐3434 located in the northern South China Sea was investigated to reveal terrigenous sediment response to the East Asian monsoon evolution during the last glaciation. Clay mineralogical variations indicate clear millennial‐scale oscillations that are mainly due to rapid changes in the proportion of smectite to illite and chlorite. Smectite is derived predominantly from rapid chemical weathering of volcanic rocks in Luzon under strong summer monsoon, while illite and chlorite are mainly sourced from Taiwan through reinforced physical erosion. Thus, the smectite/(illite + chlorite) ratio is adopted to reconstruct the East Asian summer monsoon evolution during the last glaciation. Rapid increases in the smectite/(illite + chlorite) ratio imply strengthened summer monsoon occurred during Dansgaard‐Oeschger and Bølling‐Allerød interstadials. In contrast, rapid decreases in the ratio indicate relatively weakened summer monsoon happened during Heinrich and Younger Dryas stadials. These millennial‐scale climatic signals documented by clay mineralogical compositions of deep‐sea sediments in the South China Sea can be better preserved in calm deeper‐water sedimentary environments. Our study highlights the prompt responses of the East Asian monsoon system to millennial‐scale climatic changes occurred in high‐latitude Northern Hemisphere through contemporaneous chemical weathering of volcanic rocks and/or sediment supply variations under strong physical erosion in the low‐latitude South China Sea, implying an atmospheric teleconnection from the North Atlantic to the Asian monsoon region.

In this study, paleoproductivity on millennial scales was precisely reconstructed from core MD12‐3428cq in the northern South China Sea (SCS) over the past 24 kyr, based on a transfer function derived from the strong exponential negative correlation between relative abundance of Florisphaera profunda (%FP) in core top sediments and basin‐wide satellite‐based primary productivity (PP) in the SCS. To detect the potential driving mechanisms of PP, correlation analyses were carried out among our PP records and other paleoenvironment parameters. PP peaked during 18–15 ka in parallel with the strong East Asian Winter Monsoon (EAWM). From 15 ka to the early Holocene, a decrease in PP coincided with sea level progradation and weakening of EAWM, which ultimately reduced fluvial nutrient levels and wind‐driven upper water column mixing. Since the middle Holocene, gradually more frequent El Niño‐Southern Oscillation (ENSO) events have taken place, further decreasing PP by injecting oligotrophic Kuroshio water masses into the northern SCS. Associated findings conclusively indicated that the main controlling factors of PP in the northern SCS have shifted from EAWM (glacial) to ENSO (interglacial) over the past 24 kyr.

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