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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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Data Archive of Mid-21st Century Projections for the Amundsen Sea (Western Antarctica)
A 3-D numerical model was used for multi-decadal eddy-resolving simulations of the Amundsen Sea embayment (Antarctica). A control simulation covered the historical period 2006-2023 (~2 decades) under realistic atmospheric and oceanic conditions. Three additional simulations representing the mid-21st century were conducted based on future projections from CMIP6 models ACCESS-CM2, MPI-ESM1-2-HR, MRI-ESM2-0 (scenario SSP2-4.5). These three CMIP6 models were selected based on their realism during the historical period as well as their diversity in terms of resolution and level of warming. The four simulations provided information about the regional hydrography, oceanic circulation, sea ice cover, ice shelf basal melt rates, and biogeochemical conditions (nitrogen and iron). The four simulations were then condensed into daily climatologies in order to summarize changes in the seasonal cycle of the Amundsen embayment in response to the projected warming. The present archive includes the four daily climatologies as well as all the information required to repeat the numerical experiments (code and input files).
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- Award ID(s):
- 1941292
- PAR ID:
- 10598163
- Publisher / Repository:
- Virginia Institute of Marine Science
- Date Published:
- Edition / Version:
- 1
- Subject(s) / Keyword(s):
- Antarctica, Amundsen Sea, Ice shelves, Oceanography, Cryosphere, Modeling, ROMS, Sea ice, Southern Ocean, Polynyas, Blooms, Carbon
- Format(s):
- Medium: X Size: 650GB Other: nc
- Size(s):
- 650GB
- Institution:
- William & Mary, Virginia Institute of Marine Science
- Sponsoring Org:
- National Science Foundation
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