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Grain-size analyses, coupled with end-member modelling, have been performed on the terrigenous fraction of two Leg 184 Ocean Drilling Program sites (1144 and 1146) from the South China Sea. The grain-size distributions over the last 1.8 Ma enable a new interpretation of their connections to sea-level variations and East Asian monsoon strength. Previous investigations in this area have associated grain-size variability with enhanced eolian input during glacial stages. End-member modelling downgrades the importance of this eolian contribution and indicates that the sediments can be described as a mixture of three end-members: fluvial mud inputs, shelf reworking and river mouth migration. Grain-size variations in the Pleistocene section of the cores indicate a multiple-stage evolution: (i) from 1.8 to 1.25 Ma, the downcore grain-size variations are low but show a correspondence between monsoon rainfall intensity and the fine grain-sized fluvial inputs; no link with sea-level variations is noticeable; (ii) from 1.25 to 0.9 Ma, there is an increase (decrease) in the intermediate (fine) end-member (not, vert, similar 100 kyr cycle) that is associated with the onset of a stronger summer monsoon and modest shelf reworking; (iii) from 0.9 to 0 Ma the grain-size record is dominated by global sea-level variations; each glacial stage is associated with extensive shelf reworking and conveyance of coarse particles to the basin

International audienceThe last glacial period, showing the progressive development of large boreal ice sheets, was punctuated by large climatic excursions. These excursions were triggered mainly by atmosphere-ocean-ice coupled dynamics and are thus exemplary case studies of natural climate variability. To characterize the sea-surface palaeohydrographical changes accompanying these oscillations along the European margin, we have integrated new palynological data (dinocysts) acquired on core MD99-2281 (60°N, Faeroe Margin) during Marine Isotope Stage 2 in a latitudinal transect including published cores MD95-2002 (47°N, Celtic Margin) and MD95-2010 (66°N, Vöring Plateau). This transect is superimposed on the modern North Atlantic Drift pathway, but also at the outskirts of glacial European ice sheets, thus ideally located to track sea-ice extent and ice-sheet instabilities through time. The results show a coherent and sensitive response of sea-surface environments to the complex chain of abrupt events that punctuated the end of the last glacial period. The Last Glacial Maximum was marked by large seasonal contrasts of temperatures, whereas Heinrich events (HE) were characterized by a sharp cooling and sea-ice development. A tripartite structure is identified within HE1, with indices of melting at 19k cal a BP, followed by a temperate phase synchronous of a relative stability of ice sheets, and a terminal phase (17.5-15k cal a BP) characteristic of the 'conventional Laurentian' HE1

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