Suspended particle dynamics and fluxes in an Arctic fjord (Kongsfjorden, Svalbard)

Florian Meslard (1) , François Bourrin (1) , Gael Many (2, 1) , Philippe Kerhervé (1)

1 CEFREM - Centre de Formation et de Recherche sur les Environnements Méditérranéens
2 SHOM - Service Hydrographique et Océanographique de la Marine

An experiment was carried out during summer 2015 in the inner part of the Kongsfjorden to study the inputs of meltwater and behaviour of associated suspended particles. We used a wide range of oceanographic instruments to assess the hydrological and hydrodynamic characteristics of coastal waters. The transfer of suspended particles occurs from a large surface plume fed by two main sources: the most important one is the upwelling of fresh and turbid water coming from a tide-water glacier: the Kronebreen, and the second one from a continental glacier: the Kongsvegen. We estimated that these two sources discharged about 2.48 ± 0.37 × 10⁶ t of suspended sediments during the two months of melting. The major part of these sediments is deposited within the first kilometre due to flocculation phenomena. Flocculation is initiated below the surface turbid plume and is mainly caused by the salinity gradient and high suspended particle concentration. Finally, our estimates of suspended particle fluxes by a typical Arctic coastal glacier showed the need to consider suspended sediment fluxes from high-latitude areas into global budgets in the context of climate change.

Mots clés: sediment fluxes; sediment particles; Kongsfjorden; Artic fjord

Domaines: Océanographie; Interfaces continentales, environnement

Florian Meslard, François Bourrin, Gael Many, Philippe Kerhervé. Suspended particle dynamics and fluxes in an Arctic fjord (Kongsfjorden, Svalbard). Estuarine, Coastal and Shelf Science, 2018, 204, pp.212-224. ⟨10.1016/j.ecss.2018.02.020⟩. ⟨hal-01764323⟩