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The long-term evolution of deep-sea turbidity current activity is closely related to climate and sea level changes; however, the impact of abrupt climate change (e.g. millennial-scale events in high northern latitudes) is poorly known. In this paper, deep-sea turbidite records in the western part of the lower Bengal Fan were identified since the Last Glacial Maximum (LGM) to investigate the effects of abrupt climate change on the development of the Earth's largest deep-sea fan. Our records show a termination of turbidite activity in the western lower fan at 16.6 ka–15.4 ka almost contemporaneous with Heinrich 1 event (a cooling stadial in high northern latitudes). The trigger of this termination in turbidite activity may have been a sharp decrease in erosion rates during a time of relatively stable sea level and rapid source-sink processes. The subsequent episodes of the Bolling/Allerod warm interstadial and Younger Dryas cold stadial and the rapid sea level rise event that followed possibly induced adjustment of turbidity current activities in the Bengal Fan, as indicated by other published records. In summary, we show that close links exist between abrupt climate changes in the high-latitude Northern Hemisphere and deep-sea turbidity current activity in the low-latitude South Asia. • Deep-sea turbidite records in the Bengal Fan since LGM were recovered. • Termination of turbidite in the western lower fan was triggered by HS1 event. • Links between high latitudes climate and low latitudes sedimentation were revealed. [ABSTRACT FROM AUTHOR]

The Indian summer monsoon (ISM) significantly influences the evolution of the natural environment and the development of human societies in South Asia, however, the spatiotemporal nature of the maximum ISM precipitation remains uncertain. We present the first sedimentary sporopollen record from core ADM-C1 in the southern Andaman Sea, covering the past 11.2 ka to better understand the evolutionary history of the ISM. We use the percentage values of tropical–subtropical broad-leaved tree pollen to indicate regional precipitation. These pollens reached their highest abundances during ∼11–9 cal ka BP, indicating warmest and wettest climatic conditions in the southern Andaman Sea region. The subsequent retreat of the tropical–subtropical broad-leaved forest could reflect a gradual decline in ISM. By comparing numerous ISM precipitation records, we divided these records into two patterns: the timing of maximum ISM precipitation of Pattern 1 records during the early-Holocene (11–9 cal ka BP) and that of Pattern 2 records after 9 cal ka BP. The shift in the maximum ISM precipitation from Pattern 1 to Pattern 2 reflects a northward migration during the early–mid-Holocene, probably induced by the northward migration of the mean position of the Intertropical Convergence Zone (ITCZ). Furthermore, the ∼1.8 ka temporal lag between Patterns 1 and 2 could have resulted from the relatively weak Atlantic Meridional Overturning Circulation, which might have hindered the ITCZ from migrating northward before 9 cal ka BP. • Sporopollen record from the Andaman Sea indicates a maximum Indian summer monsoon (ISM) precipitation during 11–9 cal ka BP. • The maximum ISM precipitation records during the Holocene were divided into two patterns. • The temporal lag between the two patterns resulted from the weak Atlantic Meridional Overturning Circulation. • The northward shift of the mean position of the Intertropical Convergence Zone induced the shift in the two patterns. [ABSTRACT FROM AUTHOR]