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Satellite images from Antarctica reveal important changes in the coastal icescape (fast-ice, icebergs and ice shelves) but these yearly changes and their impacts on the coastal circulation and ice shelf basal melt rates are not represented in the Earth System Models used to project future sea level rise. The impacts of these yearly icescape changes are thus investigated using a high-resolution regional ocean-ice shelves-sea ice coupled model of the Amundsen Sea (Antarctica). A set of nine semi-idealized experiments were designed to highlight the impacts of (a) the collapse of the Thwaites Glacier Tongue, (b) the disappearance of the Bear Ridge Iceberg Chain and tabular iceberg B22, and (c) presence/absence of a fast-ice cover between Thwaites and Pine Island ice shelves, in both cold and warm background hydrological conditions. The dataset features the results of the nine experiments and reveals changes in sea ice concentrations, coastal oceanic circulation and oceanic heat supply to the ice shelf cavities, ice shelf basal melt rates, hydrological conditions, and fluxes of heat/freshwater at the sea surface. These model results are archived in self-documented NetCDF files with the appropriate metadata for each variable. The dataset includes a 'readme file' providing an overview of the archive as well as additional information regarding the model results.
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Dataset: A numerical simulation of the ocean, sea ice and ice shelves in the Amundsen Sea (Antarctica) over the period 2006-2022 and its associated code and input files
A three-dimensional numerical model of the Amundsen Sea (Antarctica) was used to simulate the period Jan.2006-Mar.2022 under consistent atmospheric/oceanic forcings, bathymetry/ice shelf topography, and model equations/parameters. The model is an implementation of the Regional Ocean Modeling System (ROMS, https://www.myroms.org/) with extensions for sea ice (Budgell 2005) and ice shelves (Dinniman et al. 2011). It simulates the ocean hydrography and circulation, sea ice thermodynamics and dynamics, and the basal melt of the ice shelves, with a uniform horizontal mesh of 1.5km and 20 topography-following vertical levels. Forcings include the ERA5 reanalysis (3-hourly), 10 tidal constituents from CATS 2008, and ocean/sea ice conditions at the edges of the model domain taken from the 5km-resolution circumpolar model of Dinniman et al. 2020 and from daily SSM/I satellite images. The model outputs are divided into nine directories each containing two years worth of model results (run661-669) in the NetCDF format. Each directory contains: daily-averaged model fields (roms_avg_xxxx.nc), instantaneous snapshots every 3 hours for select fields (roms_qck_xxxx.nc), and instantaneous snapshots every 30 days (roms_his_xxxx.nc). All the metadata information necessary for the interpretation of the model outputs (dimensions, units, etc) is included inside the NetCDF files. The NetCDF files follow the CF conventions and can be opened with various software that are open source and freely available over the Internet. In addition to the model outputs, this archive includes the computer code as well as the input files necessary for reproducing the model outputs of this archive.
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- Award ID(s):
- 1941292
- PAR ID:
- 10532664
- Publisher / Repository:
- William & Mary. Virginia Institute of Marine Science
- Date Published:
- Edition / Version:
- 1.0
- Subject(s) / Keyword(s):
- Amundsen Sea Antarctica model ocean sea ice ice shelves continental shelf polynyas ROMS polar Southern Ocean
- Format(s):
- Medium: X Other: NetCDF
- Location:
- Amundsen Sea, Antarctica
- Institution:
- Virginia Institute of Marine Science (VIMS), William & Mary
- Sponsoring Org:
- National Science Foundation
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