Mission to the outlet of the Kronebreen glacier in the Arctic

Lancement dune bouteille Niskins 230px

The Svalbard Islands are currently the area of the Arctic most affected by the effects of climate change.
In the archipelago, the numerous fjords show more or less advanced signs of its consequences.
Some have now completely lost their sea ice and show a remarkable summer thawing of land glaciers, others show a small decrease in winter sea ice volumes.

Kongsfjorden (NW Svalbard) is in an intermediate phase, with a drastic reduction of the winter sea ice and a lengthening of the summer melting period of land ice.
The direct consequence of these thawing processes is the massive input of sediment eroded from the mainland and transported into the fjord by the meltwater, with a significant impact on primary productivity (reduced due to water turbidity), and on the physical and chemical stability of benthic habitats.

The BEGIN (BEnthos under Arctic melting Glacier Influence) project aims to understand the biogeochemical functioning of benthic ecosystems under the influence of sediment loads transported to the fjord by runoff from Arctic terrestrial and tidal glaciers during melt periods.

A tri-annual monitoring of the response of benthic foraminifera and the food web to geochemical fluctuations (organic matter availability) and sedimentary instabilities (recurrent massive deposits) is organized in Kongsfjorden, at the outlet of the Kronebreen glacier in Svalbard. The 1st mission in Ny Ålesund (79°N) took place from April 26 to May 10, 2021.

In the laboratory, different sediment supply scenarios (frequencies and quantities) will be tested to evaluate the resilience time of microhabitats and faunas after massive depositional events and to determine the effect of colonization of recent semi-fluid deposits by meiofauna in terms of compaction/stabilization of the sediment column and distribution of geochemical microhabitats.

 

Ny Alesund Port 800px
Ny Alesund Port - © Hélène Howa - LPG

 

High spatial resolution faunistic and geochemical analyses will be performed by a combination of techniques under development at LPG, 2D gels and CT-Scan of cores.

The BEGIN project is funded by the CNRS, LEFE INSU project, and is led by Pia Nardelli, Associate Professor at the University of Angers, attached to the LPG. It is co-financed by the project KONBHAS - Kongsfjorden new Benthic HAbitatS (Agnès Baltzer, OSUNA) and the French Polar Institute.

 

© Image "Launch of a Niskins bottle" - Hélène Howa - LPG