DOI: 10.5281/zenodo.17122653
title: SNOWISO model snow surface and firn core simulations at Dome C, East Antarctica (EPICA Dome C ice core drilling site)

description: This model dataset includes SNOWISO v3 snowpack simulations of the stable water isotopes (δ18O, δD, d-excess) and is the result of snow surface and snowpack simulations in: Ollivier, I., Steen-Larsen, H.C., Dietrich, L.J., Cauquoin, A., Stenni, B., Werner, M., and Landais, A. (submitted). Post-depositional Processes Alter the Seasonal and Multi-decadal Water Isotopic Records in Antarctic Snow and Firn. Journal of Geophysical Research: Atmospheres.

This model dataset consists of different simulation results, gathered in three folders:



sensitivity_tests.zip: contains 38 csv files with the results of the model sensitivity tests on the choice of the formulations for the ice-vapor equilibrium fractionation coefficients (alphas), the choice of the model parameter zsc, and the choice of the kinetic fractionation coefficient (k18O). Files "ST_alphas_Ellehoj_zsc_xx.csv" contain the results of the simulations performed with alphas from Ellehøj et al., 2013 (https://doi.org/10.1002/rcm.6668); files "ST_alphas_MMN_zsc_xx.csv" contain the results of the simulations performed with alphas from Majoube, 1970 (https://doi.org/10.1038/2261242a0) and Merlivat and Nief, 1967 (https://doi.org/10.3402/tellusa.v19i1.9756). The last part of the file name indicates which zsc was used (from 0.01 to 0.1 m, one file / zsc). The parameter k18O varies from 0 to 0.008 (one column / k18O, see columns description below). In each file, the column "datetime" contains the age of each snowpack layer; the columns "z_xx" contains the depth of each snowpack layer; the columns "d18O_xx" contains the δ18O composition of each snowpack layer; the columns "dD_xx" contains the δD composition of each snowpack layer; and the columns "dxs_xx" contains the d-excess composition of each snowpack layer. The second part of the column name indicates which model run it corresponds to:



xx_ndnf: diffusion switched OFF, isotopic fractionation during vapor exchange switched OFF

xx_dnf: diffusion switched ON, isotopic fractionation during vapor exchange switched OFF

xx_ndKINf_k18O_xx: diffusion switched OFF, isotopic fractionation during vapor exchange switched ON (k18O specified in column name)

xx_dKINf_k18O_xx: diffusion switched ON, isotopic fractionation during vapor exchange switched ON (k18O specified in column name)



snow_surface.zip: contains 2 csv files with the results of the simulations for the snow surface cell. Simulations were performed with alphas from Ellehøj et al., 2013 (https://doi.org/10.1002/rcm.6668) and a kinetic fractionation coefficient k18O of 0. File "snow_surface_alphas_Ellehoj_k18O_0_zsc_0.01.csv" contains the results for a zsc of 0.01 m; file "snow_surface_alphas_Ellehoj_k18O_0_zsc_0.04.csv" contains the results for a zsc of 0.04 m. In each file, the column "datetime" contains the age of the snow surface; the columns "d18O_xx" contains the δ18O composition of the snow surface; the columns "dD_xx" contains the δD composition of the snow surface; and the columns "dxs_xx" contains the d-excess composition of the snow surface. The second part of the column name indicates which model run it corresponds to:



xx_ndnf: diffusion switched OFF, isotopic fractionation during vapor exchange switched OFF

xx_dnf: diffusion switched ON, isotopic fractionation during vapor exchange switched OFF

xx_ndKINf: diffusion switched OFF, isotopic fractionation during vapor exchange switched ON (k18O = 0)

xx_dKINf: diffusion switched ON, isotopic fractionation during vapor exchange switched ON (k18O = 0)



snowpack_profiles.zip: contains 8 csv files with the results of the simulations for the snowpack profiles over the period 1990-2023. Simulations were performed with alphas from Ellehøj et al., 2013 (https://doi.org/10.1002/rcm.6668), a kinetic fractionation coefficient k18O of 0, and a zsc of 0.04 m. Files "snowpack_1990_2023_cst_prates_xx.csv" contain the results of the simulations performed with constant precipitation rates; files "snowpack_1990_2023_ECHAM_prates_xx.csv" contain the results of the simulations performed with precipitation rates from ECHAM6-wiso. In each file, the column "datetime" contains the age of each snowpack layer; the columns "z" contains the depth of each snowpack layer; the columns "d18O" contains the δ18O composition of each snowpack layer; the columns "dD" contains the δD composition of each snowpack layer; and the columns "dxs" contains the d-excess composition of each snowpack layer. The second part of the file name indicates which model run it corresponds to:



xx_ndnf.csv: diffusion switched OFF, isotopic fractionation during vapor exchange switched OFF

xx_dnf.csv: diffusion switched ON, isotopic fractionation during vapor exchange switched OFF

xx_ndKINf.csv: diffusion switched OFF, isotopic fractionation during vapor exchange switched ON (k18O = 0)

xx_dKINf.csv: diffusion switched ON, isotopic fractionation during vapor exchange switched ON (k18O = 0)




 

The scientific theory of the SNOWISO model is described in:Wahl, S., Steen‐Larsen, H.C., Hughes, A.G., Dietrich, L.J., Zuhr, A., Behrens, M., Faber, A.K. and Hörhold, M., 2022. Atmosphere‐Snow Exchange Explains Surface Snow Isotope Variability. Geophysical Research Letters, https://doi.org/10.1029/2022GL099529.

The documentation of the SNOWISO model v2 operational set-up and simulation results for the Greenland Ice Sheet is given in:Dietrich, L.J., Steen-Larsen, H.C., Wahl, S., Jones, T.R., Town, M. and Werner, M., 2023. Snow-atmosphere humidity exchange at the ice sheet surface alters annual mean climate signals in ice core records. Geophysical Research Letters, https://doi.org/10.1029/2023GL104249.