SNOWPACK simulations for Thwaites Cavity and Channel AMIGOS sites in West Antarctica

Compressed zip file, containing the SNOWPACK model simulations used in the manuscript: Maclennan, M. L., Lenaerts, J. T. M., Shields, C. A., Hoffman, A. O., Wever, N., Thompson-Munson, M., Winters, A. C., Pettit, E. C., Scambos, T. A., and Wille, J. D.: Climatology and Surface Impacts of Atmospheric Rivers on West Antarctica, The Cryosphere Discuss. [preprint], https://doi.org/10.5194/tc-2022-101, in review, 2022.

MeteoIO and SNOWPACK are software published under the GNU LGPLv3 license by the WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland at https://gitlabext.wsl.ch/snow-models. The repository used to develop the versions of MeteoIO and SNOWPACK used in this study can be accessed at https://github.com/snowpack-model/snowpack (doi: 10.5281/zenodo.3891845) with the exact version corresponding to commit 149c586 (doi: 10.5281/zenodo.7331794).

The workflow consists of two phases. First, using MERRA-2 reanalysis as forcing, a spinup is performed for the MERRA-2 grid point closest to the AMIGOS weather stations Channel (CHA) and Cavity (CAV).

To perform the spinup:

1. navigate to the ./simulations_spinup/ directory
2. edit the following line in the file spinup.rc, to modify the path where the time_shift_script can be found: time_shift_script="/path/to/snowpack/Source/snowpack/tools/timeshift_sno_files.sh" This script can be found in the SNOWPACK repository.
3. Execute the two SNOWPACK spinup simulations specified below. Change the path to point to the SNOWPACK binary executable. The simulations are performed for the two sites, which use the same meteorological forcing, but have a different end date specified for the simulation (corresponding to the installation date of the AMIGOS weather station):

bash spinup.sh "/path/to/usr/bin/snowpack -c cfgfiles/THWAITES_CAV.ini -e 2020-01-10T01:00 > log/THWAITES_SPINUP.log 2>&1" startover=1
bash spinup.sh "/path/to/usr/bin/snowpack -c cfgfiles/THWAITES_CHA.ini -e 2020-01-16T01:00 > log/THWAITES_SPINUP.log 2>&1" startover=1

Brief overview of the files in the simulations_spinup directory:

• base.ini: SNOWPACK settings shared by all simulations
• spinup.ini: Specific settings used when the spinups are being performed
• final.ini: Specific settings used when the final simulation is being performed, after the spinup has completed
• spinup.rc: Specific spinup settings imported by the spinup.sh script
• spinup.sh: bash script to perform spinups
• cfgfiles/THWAITES_CAV.ini: Specific model settings for the Cavity site. This *.ini file is specified to SNOWPACK, and it directs to include other *ini files.
• cfgfiles/THWAITES_CHA.ini: Specific model settings for the Channel site. This *.ini file is specified to SNOWPACK, and it directs to include other *ini files.
• current_snow/THWAITES.sno: *.sno file used for the restarts within the spinup procedure
• log: directory to store simulation logs. Note that in the commands above, we redirect stdout and stderr to files in this directory
• output: directory to store model outputs. See SNOWPACK documentation for more details. *.smet and *.pro files can be visualized using NiViz
• smet: directory to store the meteorological forcing data for the simulations
• snow_init/THWAITES.sno: initial *.sno files used to start the spinup

To perform the final simulations, covering the atmospheric river period:

1. navigate to the ./simulations_final/ directory
2. execute a snowpack simulation for each *.ini file in the cfgfiles directory:

for f in cfgfiles/*ini
do
    /path/to/usr/bin/snowpack -c ${f} -e NOW
done

The following simulations will be performed:

Brief overview of the files in the simulations_final directory:

• base.ini: SNOWPACK settings shared by all simulations (identical to base.ini in simulations_spinup directory
• cfgfiles: Specific model settings for each simulation as listed in the table above.
• current_snow: The initial *.sno file containing the initial firn conditions
• final.ini: Settings used by all simulations in this directory
• output: directory to store model outputs. See SNOWPACK documentation for more details. *.smet and *.pro files can be visualized using NiViz
• prepare_snowpack.sh: bash script setting up the final simulations after the simulations in simulations_spinup completed. Among others, the code to mark the installation reference layers for the snow depth measurements is included in this script.
• smet: ERA5 and MERRA-2 forcing data, as well as snow height for Cavity and Channel (cavity_hs.smet and channel_hs.smet, respectively) as well as the other meteorological parameters (cavity_meteo.smet and channel_meteo.smet, respectively).

Note:
Please refer to doi: 10.15784/601552 and doi: 10.15784/601549 for the AMIGOS weather station data