TY - JOUR

T1 - Review article

T2 - How does glacier discharge affect marine biogeochemistry and primary production in the Arctic?

AU - Hopwood, Mark J.

AU - Carroll, Dustin

AU - Dunse, Thorben

AU - Hodson, Andy

AU - Holding, Johnna M.

AU - Iriarte, José L.

AU - Ribeiro, Sofia

AU - Achterberg, Eric P.

AU - Cantoni, Carolina

AU - Carlson, Daniel F.

AU - Chierici, Melissa

AU - Clarke, Jennifer S.

AU - Cozzi, Stefano

AU - Fransson, Agneta

AU - Juul-Pedersen, Thomas

AU - Winding, Mie H. S.

AU - Meire, Lorenz

N1 - Funding Information: Mark Hopwood was financed by the DFG (award number HO 6321/1-1). Andy Hodson was supported by Joint Programming Initiative (JPI-Climate Topic 2: Russian Arctic and Boreal Systems) award 71126 and Research Council of Norway grant 294764. Johnna Holding was supported by Marie Curie grant GrIS-Melt (752325). Lorenz Meire was supported by the VENI program from the Dutch Research Council (NWO grant 016.Veni.192.150). José L. Iriarte received support from the FONDECYT 1170174 project. Sofia Ribeiro received support from Geocenter Denmark (project GreenShift). Thorben Dunse was supported by the Nordforsk-funded project (GreenMAR). The authors thank all conveners and participants of the IASC cross-cutting activity &qout;The importance of Arctic glaciers for the Arctic marine ecosystem&qout; hosted by the Cryosphere Working Group/Network on Arctic Glaciology and the Marine Working Group. IASC funding to support early career scientist attendance is gratefully acknowledged. Figure 7 and all linear regressions were produced in SigmaPlot. Funding Information: (award number HO 6321/1-1). Andy Hodson was supported by Joint Programming Initiative (JPI-Climate Topic 2: Russian Arctic and Boreal Systems) award 71126 and Research Council of Norway grant 294764. Johnna Holding was supported by Marie Curie grant GrIS-Melt (752325). Lorenz Meire was supported by the VENI program from the Dutch Research Council (NWO grant 016.Veni.192.150). José L. Iriarte received support from the FONDECYT 1170174 project. Sofia Ribeiro received support from Geocenter Denmark (project GreenShift). Thorben Dunse was supported by the Nordforsk-funded project (GreenMAR). Funding Information: Financial support. Mark Hopwood was financed by the DFG Publisher Copyright: © 2020 Copernicus GmbH. All rights reserved.

PY - 2020

Y1 - 2020

N2 - Freshwater discharge from glaciers is increasing across the Arctic in response to anthropogenic climate change, which raises questions about the potential downstream effects in the marine environment. Whilst a combination of long-term monitoring programmes and intensive Arctic field campaigns have improved our knowledge of glacier-ocean interactions in recent years, especially with respect to fjord/ocean circulation, there are extensive knowledge gaps concerning how glaciers affect marine biogeochemistry and productivity. Following two cross-cutting disciplinary International Arctic Science Committee (IASC) workshops addressing the importance of glaciers for the marine ecosystem, here we review the state of the art concerning how freshwater discharge affects the marine environment with a specific focus on marine biogeochemistry and biological productivity. Using a series of Arctic case studies (Nuup Kangerlua/Godthäbsfjord, Kongsfjorden, Kangerluarsuup Sermia/Bowdoin Fjord, Young Sound and Sermilik Fjord), the interconnected effects of freshwater discharge on fjord-shelf exchange, nutrient availability, the carbonate system, the carbon cycle and the microbial food web are investigated. Key findings are that whether the effect of glacier discharge on marine primary production is positive or negative is highly dependent on a combination of factors. These include glacier type (marine- or land-terminating), fjord-glacier geometry and the limiting resource(s) for phytoplankton growth in a specific spatio-temporal region (light, macronutrients or micronutrients). Arctic glacier fjords therefore often exhibit distinct discharge-productivity relationships, and multiple case-studies must be considered in order to understand the net effects of glacier discharge on Arctic marine ecosystems.

AB - Freshwater discharge from glaciers is increasing across the Arctic in response to anthropogenic climate change, which raises questions about the potential downstream effects in the marine environment. Whilst a combination of long-term monitoring programmes and intensive Arctic field campaigns have improved our knowledge of glacier-ocean interactions in recent years, especially with respect to fjord/ocean circulation, there are extensive knowledge gaps concerning how glaciers affect marine biogeochemistry and productivity. Following two cross-cutting disciplinary International Arctic Science Committee (IASC) workshops addressing the importance of glaciers for the marine ecosystem, here we review the state of the art concerning how freshwater discharge affects the marine environment with a specific focus on marine biogeochemistry and biological productivity. Using a series of Arctic case studies (Nuup Kangerlua/Godthäbsfjord, Kongsfjorden, Kangerluarsuup Sermia/Bowdoin Fjord, Young Sound and Sermilik Fjord), the interconnected effects of freshwater discharge on fjord-shelf exchange, nutrient availability, the carbonate system, the carbon cycle and the microbial food web are investigated. Key findings are that whether the effect of glacier discharge on marine primary production is positive or negative is highly dependent on a combination of factors. These include glacier type (marine- or land-terminating), fjord-glacier geometry and the limiting resource(s) for phytoplankton growth in a specific spatio-temporal region (light, macronutrients or micronutrients). Arctic glacier fjords therefore often exhibit distinct discharge-productivity relationships, and multiple case-studies must be considered in order to understand the net effects of glacier discharge on Arctic marine ecosystems.

U2 - 10.5194/tc-14-1347-2020

DO - 10.5194/tc-14-1347-2020

M3 - Review

AN - SCOPUS:85084296461

VL - 14

SP - 1347

EP - 1383

JO - The Cryosphere

JF - The Cryosphere

SN - 1994-0416

IS - 4

ER -