Observed run-off and suspended sediment dynamics from a minor glacierized basin in south-west Greenland

Abstract

This study examined run-off and suspended sediment dynamics in a minor glacierized basin in south-west Greenland. A discharge (Q), turbidity (Tu) and air temperature (Tair) record was maintained for 26 days from 25 July 2009 to 19 August 2009 which was supplemented by 335 water samples analysed for suspended sediment concentration (SSC). Clear diurnal fluctuations in Tair, Q and SSC were observed. Mean Tair rose from 10.2 °C in a sunny clear Phase 1 (days 1–14) to 10.8 °C in a cloudy Phase 2 (days 15–25), mean Q increased from 3.4 m3/s in Phase 1 to 4.8 m3/s in Phase 2 and this significant increase in Q may be explained by fresh snowfall higher on the glaciers melting. Mean sampled SSC was 23 mg/l while mean predicted SSC increased from 34 mg/l in Phase 1 to 45 mg/l in Phase 2 and is assumed to be a direct result of the increased Q in Phase 2 entraining fine sediment from higher up channel banks and bars. The SSC, suspended sediment load and SSY estimated in this study are compared with a growing and updated database of sediment studies in Greenland (where data from sediment transport studies in 16 locations around Greenland are collated).