Early spring subglacial discharge plumes fuel under-ice primary production at a Svalbard tidewater glacier

0543945 - BÚ 2022 RIV DE eng J - Journal Article
Vonnahme, T. R. - Persson, E. - Dietrich, U. - Hejduková, E. - Dybwad, C. - Elster, Josef - Chierici, M. - Gradinger, R.
Early spring subglacial discharge plumes fuel under-ice primary production at a Svalbard tidewater glacier.
Cryosphere. Roč. 15, č. 4 (2021), s. 2083-2107. ISSN 1994-0416. E-ISSN 1994-0424
Institutional support: RVO:67985939
Keywords : subglacial discharge * Svalbard * tidewater glacier
OECD category: Ecology
Impact factor: 5.805, year: 2021
Method of publishing: Open access

Subglacial upwelling of nutrient-rich bottom water is known to sustain elevated summer primary productionin tidewater-glacier-influenced fjord systems. However, the importance of subglacial upwelling during the early spring season has not been considered yet. We hypothesized that subglacial discharge under sea ice is present in early spring and that its flux is sufficient to increase phytoplankton primary productivity. We evaluated the effects of the submarine discharge on primary production in a seasonally fast-ice covered Svalbard fjord (Billefjorden) influenced by a tidewater outlet glacier in April and May 2019. We found clear evidence for subglacial discharge and upwelling. Althoughthe estimated bottom-water entrainment factor (1.6) and total fluxes were lower than in summer studies, we still observed substantial impact on the fjord ecosystem and primary production at this time of the year.
Permanent Link: http://hdl.handle.net/11104/0321037