Continued glacial retreat linked to changing macronutrient supply along the West Antarctic Peninsula

Jones, Rhiannon L.; Meredith, Michael P. ORCID: https://orcid.org/0000-0002-7342-7756; Lohan, Maeve C.; Woodward, E. Malcolm S.; Van Landeghem, Katrien; Retallick, Kate; Flanagan, Oliver; Vora, Mehul; Annett, Amber L.. 2023 Continued glacial retreat linked to changing macronutrient supply along the West Antarctic Peninsula. Marine Chemistry, 251, 104230. 13, pp. https://doi.org/10.1016/j.marchem.2023.104230

Before downloading, please read NORA policies.

Preview

Text (Open Access) © 2023 The Authors. Published by Elsevier B.V. 1-s2.0-S0304420323000269-main.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (9MB) | Preview

Abstract/Summary

At the West Antarctic Peninsula (WAP), continued atmospheric and oceanic warming is causing significant physical and biogeochemical changes to glaciers and the marine environment. We compare sediment sources and drivers of macronutrient distributions at two bays along the WAP during austral summer 2020, using radioactive radium and stable oxygen isotopes to trace sedimentary influences and quantify different freshwater inputs. In the Ryder Bay, where the Sheldon Glacier is marine-terminating, radium activities at the sediment-water interface indicate considerable benthic mixing. Using radium isotope activity gradients to resolve radium and macronutrient fluxes, we find buoyant meltwater proximal to the glacier drives vigorous mixing of sediment and entrainment of macronutrient deep waters, on the order of 2.0 × 105 mol d−1 for nitrate. Conversely, in the Marian Cove, where the Fourcade Glacier terminates on land, low salinities and oxygen isotopes indicate a meltwater-rich surface layer <1 m thick and rich in sediment, and strong vertical mixing to the seafloor. A continued shift to land-terminating glaciers along the WAP may have a significant impact upon nutrient and sediment supply to the euphotic zone, with impacts upon primary productivity and carbon uptake efficiency. The future of primary production, carbon uptake, and food web dynamics is therefore linked to glacier retreat dynamics in the many fjords along the WAP.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1016/j.marchem.2023.104230
ISSN:	0304-4203
Additional Keywords:	Radium, Macronutrient cycling, Glacial retreat, West Antarctic Peninsula
Date made live:	03 Apr 2023 08:25 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/532907

Actions (login required)

View Item

Document Downloads

More statistics for this item...