The biogeochemical impact of glacial meltwater from Southwest Greenland

Hendry, Katharine R.; Huvenne, Veerle A.I.; Robinson, Laura F.; Annett, Amber; Badger, Marcus; Jacobel, Allison W.; Ng, Hong Chin; Opher, Jacob; Pickering, Rebecca A.; Taylor, Michelle L.; Bates, Stephanie L.; Cooper, Adam; Cushman, Grace G.; Goodwin, Claire; Hoy, Shannon; Rowland, George; Samperiz, Ana; Williams, James A.; Achterberg, Eric P.; Arrowsmith, Carol; Brearley, J. Alexander; Henley, Sian F.; Krause, Jeffrey W.; Leng, Melanie J.; Li, Tao; McManus, Jerry F.; Meredith, Michael P.; Perkins, Rupert; Woodward, E. Malcolm S.

Abstract

Biogeochemical cycling in high-latitude regions has a disproportionate impact on global nutrient budgets. Here, we introduce a holistic, multi-disciplinary framework for elucidating the influence of glacial meltwaters, shelf currents, and biological production on biogeochemical cycling in high-latitude continental margins, with a focus on the silica cycle. Our findings highlight the impact of significant glacial discharge on nutrient supply to shelf and slope waters, as well as surface and benthic production in these regions, over a range of timescales from days to thousands of years. Whilst biological uptake in fjords and strong diatom activity in coastal waters maintains low dissolved silicon concentrations in surface waters, we find important but spatially heterogeneous additions of particulates into the system, which are transported rapidly away from the shore. We expect the glacially-derived particles – together with biogenic silica tests – to be cycled rapidly through shallow sediments, resulting in a strong benthic flux of dissolved silicon. Entrainment of this benthic silicon into boundary currents may supply an important source of this key nutrient into the Labrador Sea, and is also likely to recirculate back into the deep fjords inshore. This study illustrates how geochemical and oceanographic analyses can be used together to probe further into modern nutrient cycling in this region, as well as the palaeoclimatological approaches to investigating changes in glacial meltwater discharge through time, especially during periods of rapid climatic change in the Late Quaternary.

Citation

Hendry, K. R., Huvenne, V. A., Robinson, L. F., Annett, A., Badger, M., Jacobel, A. W., Ng, H. C., Opher, J., Pickering, R. A., Taylor, M. L., Bates, S. L., Cooper, A., Cushman, G. G., Goodwin, C., Hoy, S., Rowland, G., Samperiz, A., Williams, J. A., Achterberg, E. P., Arrowsmith, C., …Woodward, E. M. S. (2019). The biogeochemical impact of glacial meltwater from Southwest Greenland. Progress in Oceanography, 176, Article 102126. https://doi.org/10.1016/j.pocean.2019.102126

• Journal Article Type: Article
• Acceptance Date: Jun 15, 2019
• Online Publication Date: Jun 17, 2019
• Publication Date: Sep 30, 2019
• Deposit Date: Jun 26, 2019
• Publicly Available Date: Jun 18, 2020
• Journal: Progress in Oceanography
• Print ISSN: 0079-6611
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 176
• Article Number: 102126
• DOI: https://doi.org/10.1016/j.pocean.2019.102126
• Keywords: Aquatic Science; Geology
• Public URL: https://nottingham-repository.worktribe.com/output/2230769
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0079661118302817
• Contract Date: Jun 26, 2019