The University of Southampton
University of Southampton Institutional Repository
Warning ePrints Soton is experiencing an issue with some file downloads not being available. We are working hard to fix this. Please bear with us.

Non-linear response of summertime marine productivity to increased meltwater discharge around Greenland

Non-linear response of summertime marine productivity to increased meltwater discharge around Greenland
Non-linear response of summertime marine productivity to increased meltwater discharge around Greenland
Runoff from the Greenland Ice Sheet (GrIS) is thought to enhance marine productivity by adding bioessential iron and silicic acid to coastal waters. However, experimental data suggest nitrate is the main summertime growth-limiting resource in regions affected by meltwater around Greenland. While meltwater contains low nitrate concentrations, subglacial discharge plumes from marine-terminating glaciers entrain large quantities of nitrate from deep seawater. Here, we characterize the nitrate fluxes that arise from entrainment of seawater within these plumes using a subglacial discharge plume model. The upwelled flux from 12 marine-terminating glaciers is estimated to be >1000% of the total nitrate flux from GrIS discharge. This plume upwelling effect is highly sensitive to the glacier grounding line depth. For a majority of Greenland’s marine-terminating glaciers nitrate fluxes will diminish as they retreat. This decline occurs even if discharge volume increases, resulting in a negative impact on nitrate availability and thus summertime marine productivity.
Hopwood, M. J.
d9e0e9d8-6b16-423e-8f1c-57146a6a2b55
Carroll, D.
5768ff5c-aa0b-49ff-ba36-3cf02eded0b8
Browning, T. J.
5ca7f9b5-c1cd-493a-aed1-b371006a59e4
Meire, L.
95e20f22-16c0-4c24-9690-01ca3844a90c
Mortensen, J.
4b8f4904-77d0-4ae1-bcb6-111b49975731
Krisch, S.
f4092c32-471c-4d97-9aa3-5d9a4c425ee9
Achterberg, E. P.
685ce961-8c45-4503-9f03-50f6561202b9
Hopwood, M. J.
d9e0e9d8-6b16-423e-8f1c-57146a6a2b55
Carroll, D.
5768ff5c-aa0b-49ff-ba36-3cf02eded0b8
Browning, T. J.
5ca7f9b5-c1cd-493a-aed1-b371006a59e4
Meire, L.
95e20f22-16c0-4c24-9690-01ca3844a90c
Mortensen, J.
4b8f4904-77d0-4ae1-bcb6-111b49975731
Krisch, S.
f4092c32-471c-4d97-9aa3-5d9a4c425ee9
Achterberg, E. P.
685ce961-8c45-4503-9f03-50f6561202b9

Hopwood, M. J., Carroll, D., Browning, T. J., Meire, L., Mortensen, J., Krisch, S. and Achterberg, E. P. (2018) Non-linear response of summertime marine productivity to increased meltwater discharge around Greenland. Nature Communications, 9 (1), [3256]. (doi:10.1038/s41467-018-05488-8).

Record type: Article

Abstract

Runoff from the Greenland Ice Sheet (GrIS) is thought to enhance marine productivity by adding bioessential iron and silicic acid to coastal waters. However, experimental data suggest nitrate is the main summertime growth-limiting resource in regions affected by meltwater around Greenland. While meltwater contains low nitrate concentrations, subglacial discharge plumes from marine-terminating glaciers entrain large quantities of nitrate from deep seawater. Here, we characterize the nitrate fluxes that arise from entrainment of seawater within these plumes using a subglacial discharge plume model. The upwelled flux from 12 marine-terminating glaciers is estimated to be >1000% of the total nitrate flux from GrIS discharge. This plume upwelling effect is highly sensitive to the glacier grounding line depth. For a majority of Greenland’s marine-terminating glaciers nitrate fluxes will diminish as they retreat. This decline occurs even if discharge volume increases, resulting in a negative impact on nitrate availability and thus summertime marine productivity.

Text
s41467-018-05488-8 - Version of Record
Available under License Creative Commons Attribution.
Download (1MB)

More information

Accepted/In Press date: 10 July 2018
e-pub ahead of print date: 12 August 2018
Published date: 12 August 2018

Identifiers

Local EPrints ID: 424162
URI: http://eprints.soton.ac.uk/id/eprint/424162
PURE UUID: 127c3597-a7ff-4d47-94f5-c9600610ec5f

Catalogue record

Date deposited: 05 Oct 2018 11:31
Last modified: 25 Nov 2021 17:29

Export record

Altmetrics

Contributors

Author: M. J. Hopwood
Author: D. Carroll
Author: T. J. Browning
Author: L. Meire
Author: J. Mortensen
Author: S. Krisch

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×