| Summary: | International audience There is a growing body of evidence demonstrating that changes in warm water inflow to Greenlandic fjords are linked to the rapid retreat of marine-terminating outlet glaciers. This process is thought to be responsible for a substantial component of the increased mass loss from the Greenland Ice Sheet over the last two decades. Sediment cores from glaciated fjords provide high-resolution sedimentological and biological proxy recordswhich can be used to evaluate the interplay of warm water inflow and glacier calving over timescales longer than the instrumental record.In this study, a short core (1.5m) positioned at the head of Kangerdlugssuaq fjord is investigated to establish a multi-proxy record of glacier behaviour and oceanographic conditions. The core covers the past ∼600 years, spanning back to the start of the Little Ice Age. Grain-size analysis is performed to quantify ice-rafted debris (IRD), a parameter related to the calving intensity of Kangerdlugssuaq glacier. Bottom current strength isreconstructed by measurements of the mean sortable silt; periods of vigorous current flow are assumed to be due to enhanced warm water inflow. A record of sea surface temperatures is derived from alkenone paleothermometry (Uk’ 37), and the origin of the alkenones is discussed (in situ vs. advection). Reconstructions of ice-oceaninteractions on a longer timescale provide a baseline to better understand the recent -and potentially future- retreat of marine-terminating glaciers in Greenland.
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