Modeling mixing and melting in laminar seawater intrusions under grounded ice

<p>Small-scale ice–ocean interactions near and within grounding zones play an important role in determining the current and future contribution of marine ice sheets to sea level rise. However, the processes mediating these interactions are simplified in large-scale models due to limited observ...

Full description

Saved in:
Bibliographic Details
Main Authors: M. S. Mamer, A. A. Robel, C. C. K. Lai, E. Wilson, P. Washam
Format: Article
Language:English
Published: Copernicus Publications 2025-08-01
Series:The Cryosphere
Online Access:https://tc.copernicus.org/articles/19/3227/2025/tc-19-3227-2025.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849225057970159616
author M. S. Mamer
A. A. Robel
C. C. K. Lai
E. Wilson
P. Washam
author_facet M. S. Mamer
A. A. Robel
C. C. K. Lai
E. Wilson
P. Washam
author_sort M. S. Mamer
collection DOAJ
description <p>Small-scale ice–ocean interactions near and within grounding zones play an important role in determining the current and future contribution of marine ice sheets to sea level rise. However, the processes mediating these interactions are simplified in large-scale models due to limited observations and computational resources, contributing to uncertainty in future projections. Previous modeling studies have demonstrated that seawater can interact with subglacial discharge upstream of the grounding zone, and recent observations appear to support this possibility. In this study, we investigate turbulent mixing of quasi-laminar intruded seawater and glacial meltwater under grounded ice using a computational fluid dynamics solver. In agreement with previous work, we demonstrate the strongest control on intrusion distance is the speed of subglacial discharge and the geometry of the subglacial environment. We show that, in the fluid regimes simulated here, and expected at ice shelf grounding zones, turbulent mixing plays a negligible role in setting intrusion distance. Basal melting from seawater intrusion produces buoyant meltwater, which may create a negative feedback by chilling and freshening near-ice water, therefore reducing further melting; however, this remains unquantified. The magnitude of modeled basal melt rates from seawater intrusion can be replicated by existing sub-ice-shelf melt parameterizations by modifying the traditionally used transfer coefficients. We conclude that, in times or places when subglacial discharge is slow, seawater intrusion can be an important mechanism of ocean-forced basal melting of marine ice sheets when considering added geometric complexities and ocean conditions.</p>
format Article
id doaj-art-cf24618d98e44d96919e94e2f08373e5
institution Kabale University
issn 1994-0416
1994-0424
language English
publishDate 2025-08-01
publisher Copernicus Publications
record_format Article
series The Cryosphere
spelling doaj-art-cf24618d98e44d96919e94e2f08373e52025-08-25T06:11:17ZengCopernicus PublicationsThe Cryosphere1994-04161994-04242025-08-01193227325110.5194/tc-19-3227-2025Modeling mixing and melting in laminar seawater intrusions under grounded iceM. S. Mamer0A. A. Robel1C. C. K. Lai2E. Wilson3P. Washam4School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USASchool of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USASchool of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USADepartment of Earth System Science, Stanford University, Stanford, CA, USADepartment of Astronomy, Cornell University, Ithaca, NY, USA<p>Small-scale ice–ocean interactions near and within grounding zones play an important role in determining the current and future contribution of marine ice sheets to sea level rise. However, the processes mediating these interactions are simplified in large-scale models due to limited observations and computational resources, contributing to uncertainty in future projections. Previous modeling studies have demonstrated that seawater can interact with subglacial discharge upstream of the grounding zone, and recent observations appear to support this possibility. In this study, we investigate turbulent mixing of quasi-laminar intruded seawater and glacial meltwater under grounded ice using a computational fluid dynamics solver. In agreement with previous work, we demonstrate the strongest control on intrusion distance is the speed of subglacial discharge and the geometry of the subglacial environment. We show that, in the fluid regimes simulated here, and expected at ice shelf grounding zones, turbulent mixing plays a negligible role in setting intrusion distance. Basal melting from seawater intrusion produces buoyant meltwater, which may create a negative feedback by chilling and freshening near-ice water, therefore reducing further melting; however, this remains unquantified. The magnitude of modeled basal melt rates from seawater intrusion can be replicated by existing sub-ice-shelf melt parameterizations by modifying the traditionally used transfer coefficients. We conclude that, in times or places when subglacial discharge is slow, seawater intrusion can be an important mechanism of ocean-forced basal melting of marine ice sheets when considering added geometric complexities and ocean conditions.</p>https://tc.copernicus.org/articles/19/3227/2025/tc-19-3227-2025.pdf
spellingShingle M. S. Mamer
A. A. Robel
C. C. K. Lai
E. Wilson
P. Washam
Modeling mixing and melting in laminar seawater intrusions under grounded ice
The Cryosphere
title Modeling mixing and melting in laminar seawater intrusions under grounded ice
title_full Modeling mixing and melting in laminar seawater intrusions under grounded ice
title_fullStr Modeling mixing and melting in laminar seawater intrusions under grounded ice
title_full_unstemmed Modeling mixing and melting in laminar seawater intrusions under grounded ice
title_short Modeling mixing and melting in laminar seawater intrusions under grounded ice
title_sort modeling mixing and melting in laminar seawater intrusions under grounded ice
url https://tc.copernicus.org/articles/19/3227/2025/tc-19-3227-2025.pdf
work_keys_str_mv AT msmamer modelingmixingandmeltinginlaminarseawaterintrusionsundergroundedice
AT aarobel modelingmixingandmeltinginlaminarseawaterintrusionsundergroundedice
AT ccklai modelingmixingandmeltinginlaminarseawaterintrusionsundergroundedice
AT ewilson modelingmixingandmeltinginlaminarseawaterintrusionsundergroundedice
AT pwasham modelingmixingandmeltinginlaminarseawaterintrusionsundergroundedice