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CICE Input Data

Tony Craig edited this page Jul 12, 2023 · 112 revisions

Forcing Data

Data files for testing CICE are too large to be kept on github. The data files necessary for testing CICE have been published on Zenodo and can be found at the path listed for each dataset. Details about each dataset can be found at the link following the Zenodo DOI.

The data files available below are designed only for testing the code, not for use in production runs or as observational data. Please do not publish results based on these data sets. Specific instructions for setting up standard tests (e.g. regression, restart) are in the User's Guide section of the documentation.

A guide to the directory structure of the CICE input data is also available. Tar files provided below will automatically unpack with this structure.

File Availability:

File name size DOI and download link compatible code versions date added(+)/ deprecated(-) file description
gx3 Datasets
CICE gx3 grid and initial condition files 27 Mb DOI CICE6.1.1+ +03/2021 more info
CICE gx3 JRA55do
forcing files
5.4 Gb DOI CICE6.4.2+ +07/2023 more info
CICE gx3 JRA55
forcing files
3.7 Gb DOI CICE6.0.2+ +10/2019 more info
CICE gx3 WW3
forcing files
2.9 Mb DOI CICE6.1.0+ +12/2019 more info
CICE gx3 NCAR_bulk
forcing files
428 Mb DOI All more info
gx1 Datasets
CICE gx1 grid and initial condition files 231 Mb DOI CICE6.2+ +08/2021 more info
CICE gx1 JRA55
forcing files
multi-year tar file
38 Gb DOI CICE6.1.1+ +3/2020 more info
CICE gx1 JRA55
forcing files
split by year
38 Gb DOI CICE6.1.1+ +3/2020 more info
CICE gx1 JRA55do
forcing files
split by year
40 Gb DOI CICE6.4.2+ +7/2023 more info
CICE gx1 WOA
forcing files
17 Mb DOI All more info
CICE gx1 COREII
forcing files
18 Gb DOI -CICE6.3.0 -10/2021 more info
CESM slab ocean forcing 24 MB DOI CICE6.1+ +04/2021 more info
tx1 Datasets
CICE tx1 grid and initial condition files 871 Kb DOI CICE6.0.2+ +5/2020 more info
CICE tx1 JRA55
forcing files
multi-year tar file
18 Gb DOI CICE6.1.1+ +5/2020 more info
CICE tx1 JRA55
forcing files
split by year
18 Gb DOI CICE6.1.1+ +5/2020 more info
CICE tx1 JRA55do
forcing files
split by year
28 Gb DOI CICE6.4.2+ +7/2023 more info
Resolution Independent Datasets
CICE and Icepack SNICAR optical properties 378 Kb DOI CICE6.2+ +1/2021 [more info]

Downloading data from Zenodo

  1. Click on the DOI link from the file availability table.

  2. Find the file you want to download.

  3. Download the file

    3a. Direct download

    Click on either the file name or the "Download" button on zenodo to download the data directly to your machine.

    3b. Download at the command line

    Cut and paste the link to the link address for the file. Then, at the command line on the system to which you want to download the data, use the wget (or curl) command to download.
    Linux:

    wget $link
    

    macOS:

    curl -O $link
    
  4. Optional, but recommended: check the MD5 checksum for the downloaded file against the provided checksum on Zenodo (below the filename).
    Linux:

    md5sum $file
    

    macOS:

    md5 $file
    

Naming standards

For any new files that will be added to the CICE Input Data files, please note the following:

  • File names must be unique from any other files in the archive.
  • The grid name should be included in the file name whenever possible.
  • New grid or initial condition files for an existing dataset will be added to the existing grid and initial condition tar files. These new files added must have unique file names from the existing files.
  • Existing forcing datasets will be updated only if there are errors found in the existing data.
  • New forcing datasets for a given grid will be added under CICE_data/forcing/<grid>/ in a new directory. These files will also be made available as an entirely new tar file.
  • Any new grid that is added will conform to the existing data structure, naming, and format. The same applies to initial condition and forcing files associated with the new grid.

Directory structure

An example of how testing data is organized follows. We recommend setting up a similar path structure. You will need to set up your own 'inputdata' path, but the organization of the CICE_data top level directory should follow the structure below and should automatically unpack as so from the ftp's *.tar.gz files. You will need to extract the data from the downloaded *tar.gz files.

If you plan to use these data for testing previous versions of CICE (V1-V5), please note that the directory structure has changed and therefore the data files will need to be moved into the proper directories for testing previous releases.

inputdata = '/glade/p/cesm/pcwg_dev/'   
   CICE_data/
       forcing/
         gx1/
            CESM/
               MONTHLY/
                  ocean_forcing_clim_2D_gx1.nc
            COREII/
               4XDAILY/
                  u_10*.data
                  v_10*.data
                  q_10*.dat
                  t_10*.dat
               MONTHLY/
                  cldf.omip.dat
                  prec.nmyr.dat
            JRA55/
               8XDAILY/
                  JRA55_03hr_forcing_2005.nc
                  JRA55_03hr_forcing_2006.nc
                  JRA55_03hr_forcing_2007.nc
                  JRA55_03hr_forcing_2008.nc
                  JRA55_03hr_forcing_2009.nc
            JRA55do/
               8XDAILY/
                  JRA55do_gx1_03hr_forcing_2005.nc
                  JRA55do_gx1_03hr_forcing_2006.nc
                  JRA55do_gx1_03hr_forcing_2007.nc
                  JRA55do_gx1_03hr_forcing_2008.nc
                  JRA55do_gx1_03hr_forcing_2009.nc
            WOA/
               MONTHLY/
                  nitrate_climatologyWOA_gx1v6f_20150107.nc
                  silicate_climatologyWOA_gx1v6f_20150107.nc
         gx3/
            ww3.20100101_efreq_remapgx3.nc
            NCAR_bulk/
               4XDAILY/
                  u_10.1997.data
                  v_10.1997.data
                  q_10.1997.dat
                  t_10.1997.dat
                  dn10.1997.dat
               MONTHLY/
                  cldf.1997.dat
                  prec.1997.dat
                  swdn.1997.dat
            JRA55/
               8XDAILY/
                  JRA55_gx3_03hr_forcing_2005.nc
                  JRA55_gx3_03hr_forcing_2006.nc
                  JRA55_gx3_03hr_forcing_2007.nc
                  JRA55_gx3_03hr_forcing_2008.nc
                  JRA55_gx3_03hr_forcing_2009.nc
            JRA55do/
               8XDAILY/
                  JRA55do_gx3_03hr_forcing_2005.nc
                  JRA55do_gx3_03hr_forcing_2006.nc
                  JRA55do_gx3_03hr_forcing_2007.nc
                  JRA55do_gx3_03hr_forcing_2008.nc
                  JRA55do_gx3_03hr_forcing_2009.nc
          tx1/
            JRA55/
               8XDAILY/
                  JRA55_03hr_forcing_tx1_2005.nc
                  JRA55_03hr_forcing_tx1_2006.nc
                  JRA55_03hr_forcing_tx1_2007.nc
                  JRA55_03hr_forcing_tx1_2008.nc
                  JRA55_03hr_forcing_tx1_2009.nc
            JRA55do/
               8XDAILY/
                  JRA55do_tx1_03hr_forcing_2005.nc
                  JRA55do_tx1_03hr_forcing_2006.nc
                  JRA55do_tx1_03hr_forcing_2007.nc
                  JRA55do_tx1_03hr_forcing_2008.nc
                  JRA55do_tx1_03hr_forcing_2009.nc
          snicar_drdt_bst_fit_60_c04262019.nc
          snicar_optics_5bnd_snow_and_aerosols.nc
      grid/
          gx1/
             grid_gx1.bin
             kmt_gx1.bin
             global_gx1.bathy.nc
             cice62_gx1_wghtmask.nc
          gx3/
             grid_gx3.bin
             kmt_gx3.bin
             grid_gx3.nc
             kmt_gx3.nc
             global_gx3.bathy.nc
          tx1/
             grid_tx1.bin
             kmt_tx1.bin
             tx1_bathy.nc
       ic/
          gx1/
             iced_gx1_v5.nc
             iced_gx1_v6.2005-01-01.nc
             iced_gx1_v6.2005-02-01.nc
             iced_gx1_v6.2005-03-01.nc
             iced_gx1_v6.2005-04-01.nc
             iced_gx1_v6.2005-05-01.nc
             iced_gx1_v6.2005-06-01.nc
             iced_gx1_v6.2005-07-01.nc
             iced_gx1_v6.2005-08-01.nc
             iced_gx1_v6.2005-09-01.nc
             iced_gx1_v6.2005-10-01.nc
             iced_gx1_v6.2005-11-01.nc
             iced_gx1_v6.2005-12-01.nc
          gx3/
             iced_gx3_v5.nc
             iced_gx3_v6.2005-01-01.nc
             iced_gx3_v6.2005-02-01.nc
             iced_gx3_v6.2005-03-01.nc
             iced_gx3_v6.2005-04-01.nc
             iced_gx3_v6.2005-05-01.nc
             iced_gx3_v6.2005-06-01.nc
             iced_gx3_v6.2005-07-01.nc
             iced_gx3_v6.2005-08-01.nc
             iced_gx3_v6.2005-09-01.nc
             iced_gx3_v6.2005-10-01.nc
             iced_gx3_v6.2005-11-01.nc
             iced_gx3_v6.2005-12-01.nc
          tx1/
             iced_tx1_v5.nc

Descriptions of Tar files

gx3 datasets:

Grid and Initial Condition files:

The gx3 grid is nominal three-degree resolution. Grid and kmt file are provided in the grid tar file. Initial conditions are also available.

JRA55 forcing:

The original JRA55 forcing Kobayashi et al. 2015 is the operational product from the Japanese Meteorological Agency. The JRA55do forcing (Tsujino et. al 2018) is a corrected version specifically for coupled sea ice-ocean simulations. The JRA55 and JRA55do files are 8x daily data (every 3hr) by year with the following fields: X-ward wind (wndewd; m/s), Y-ward wind (wndnwd; m/s), Specific Humidity (spchmd; kg/kg), Air Temperature (airtmp; K), Total Precipitation (ttlpcp; kg/(m2*s) ), Downward Surface Longwave (dlwsfc; W/m2), and Downward Surface Shortwave (glbrad; W/m2). As a result, there is no need for monthly files or cloud fraction when using the JRA55 or JRA55do forcing. Five years (2005-2009) of forcing data are available. If you publish a paper using the JRA55 or JRA55do dataset please be sure to cite the appropriate paper.

Kobayashi, S., Y. Ota, Y. Harada, A. Ebita, M. Moriya, H. Onoda, K. Onogi, H. Kamahori, C. Kobayashi, H. Endo, K. Miyaoka, K. Takahashi The JRA-55 reanalysis: general specifications and basic characteristics J. Meteor. Soc. Jpn, 93 (2015), pp. 5-48. https://doi.org/10.2151/jmsj.2015-001

Tsujino, H., S. Urakawa, H. Nakano, R.J. Small, W.M. Kim, S.G. Yeager, et al. (2018). JRA‐55 based surface dataset for driving ocean–sea‐ice models (JRA55‐do). Ocean Modelling. https://doi.org/10.1016/j.ocemod.2018.07.002

WW3 forcing:

Surface ocean wave forcing derived from the Wavewatch III (WW3) model. This is a single day of the wave spectral forcing (efreq; m2*s) that is necessary for the floe size distribution (FSD) within CICE. It is provided only for testing purposes and should not be used for publications. Users should produce their own spectral wave input. The data were derived from the wave-ice coupled run described in the following paper.

Roach, L.A., C.M. Bitz, C. Horvat, S.M. Dean. (2019). Advances in modelling interactions between sea ice and ocean surface waves. Journal of Advances in Modeling Earth Systems. https://doi.org/10.1029/2019MS001836

The WW3 model is documented in:

WAVEWATCH III Development Group. (2016). User manual and system documentation of WAVEWATCH III, version 5.16. Tech. Note 329, NOAA/NWS/NCEP/MMAB, College Park, MD, USA.

NCAR_bulk forcing:

NCAR_bulk forcing files are are available for one year (1997). Fields available 4x daily (every 6hr) at 10 meters above the surface for: zonal (u_10; m/s) and meridional (v_10; m/s) wind, specific humidity (q_10; kg/kg), air temperature (t_10; K), and air density (dn_10; kg/m3). Fields available monthly are: cloud forcing (cldf), precipitation (prec), and downward shortwave radiation (swdn; W/m2). The cloud forcing is a fraction between 0 and 1. It is not used directly in the sea ice physics, but to generate forcing fields such as downwelling longwave and shortwave radiation at the surface. In fully coupled runs the radiation is directly passed instead of cldf. The precipitation units can be set in the namelist. Precipitation is often just liquid precipitation that is converted to snow in cold enough temperatures, but the model can handle both liquid and solid precipitation. In fully coupled runs the atmospheric model provides the precipitation fields. In our test configurations the shortwave downward forcing is provided as a single value and then divided into 4 wavelength bands. In fully coupled runs, the bands are passed directly.

gx1 datasets:

Grid and Initial Condition files:

The gx1 grid is nominal one-degree resolution. Grid, kmt, and mask weight files are provided in the grid tar file. Initial conditions are also available.

JRA55 forcing:

The original JRA55 forcing Kobayashi et al. 2015 is the operational product from the Japanese Meteorological Agency. The JRA55do forcing (Tsujino et. al 2018) is a corrected version specifically for coupled sea ice-ocean simulations. The JRA55 and JRA55do files are 8x daily data (every 3hr) by year with the following fields: X-ward wind (wndewd; m/s), Y-ward wind (wndnwd; m/s), Specific Humidity (spchmd; kg/kg), Air Temperature (airtmp; K), Total Precipitation (ttlpcp; kg/(m2*s) ), Downward Surface Longwave (dlwsfc; W/m2), and Downward Surface Shortwave (glbrad; W/m2). As a result, there is no need for monthly files or cloud fraction when using the JRA55 or JRA55do forcing. Five years (2005-2009) of forcing data are available. If you publish a paper using the JRA55 or JRA55do dataset please be sure to cite the appropriate paper.

Kobayashi, S., Y. Ota, Y. Harada, A. Ebita, M. Moriya, H. Onoda, K. Onogi, H. Kamahori, C. Kobayashi, H. Endo, K. Miyaoka, K. Takahashi The JRA-55 reanalysis: general specifications and basic characteristics J. Meteor. Soc. Jpn, 93 (2015), pp. 5-48. https://doi.org/10.2151/jmsj.2015-001

Tsujino, H., S. Urakawa, H. Nakano, R.J. Small, W.M. Kim, S.G. Yeager, et al. (2018). JRA‐55 based surface dataset for driving ocean–sea‐ice models (JRA55‐do). Ocean Modelling. https://doi.org/10.1016/j.ocemod.2018.07.002

WOA forcing:

Monthly climatological nitrate and silicate concentration (mmol/m3) derived from the World Ocean Atlas and necessary for biogeochemical forcing.

National Centers for Environmental Information (2013). World Ocean Atlas Version 2. Natl. Ocn. and Atm. Admin. https://www.nodc.noaa.gov/OC5/woa13/

CORE II forcing:

COREII (Large and Yeager 2009) of forcing data for five years (2005-2009) are available. Fields available 4x daily (every 6hr) at 10 meters above the surface for: Zonal Wind (u_10; m/s), Meridional Wind (v_10; m/s), 10m Specific Humidity (q_10; kg/kg), and 10m Temperature (t_10; K). The monthly cloud forcing (cldf) and precipitation (prec) climatological fields are also available. The cloud forcing is a fraction between 0 and 1. It is not used directly in the sea ice physics, but to generate forcing fields such as downwelling longwave and shortwave radiation at the surface. In fully coupled runs the radiation is directly passed instead of cldf. The precipitation units can be set in the namelist. Precipitation is often just liquid precipitation that is converted to snow in cold enough temperatures, but the model can handle both liquid and solid precipitation. In fully coupled runs the atmospheric model provides the precipitation fields.

Large, W.G. and S.G. Yeager (2009).The global climatology of an interannually varying air-sea flux data set. Climate Dynamics, 33, 341-364. https://doi.org/10.1007/s00382-008-0441-3

CESM Slab Ocean Model Forcing:

This forcing was derived from the CESM1 Large Ensemble piControl run (Kay et al. 2015 from years 402--1503. A monthly mean climatology is created for mixed-layer depth and q-flux forcing from the POP ocean component.

Kay, J. E., Deser, C., Phillips, A., Mai, A., Hannay, C., Strand, G., Arblaster, J., Bates, S., Danabasoglu, G., Edwards, J., Holland, M. Kushner, P., Lamarque, J.-F., Lawrence, D., Lindsay, K., Middleton, A., Munoz, E., Neale, R., Oleson, K., Polvani, L., and M. Vertenstein (2015), The Community Earth System Model (CESM) Large Ensemble Project: A Community Resource for Studying Climate Change in the Presence of Internal Climate Variability, Bulletin of the American Meteorological Society, doi: 10.1175/BAMS-D-13-00255.1, 96, 1333-1349

Additional Years:

If more than 5 years of gx1 forcing data are required for your work, information and instructions about how users can generate 50 years of forcing data can also be found at ftp://ftp.cgd.ucar.edu/archive/Model-Data/CICE/gx1_50yr_scrip.tar.gz. These data will not be arranged in the directory structure described below and the user is responsible for arranging files appropriately. The Consortium recommends against using the stand-alone configuration for scientific studies. See the FAQ.

tx1 datasets:

Grid and initial condition files:

The tx3 grid is nominal one-degree resolution on a tripole grid. Grid and kmt file are provided in the grid tar file. A single initial condition file is provided.

JRA55 forcing:

The original JRA55 forcing Kobayashi et al. 2015 is the operational product from the Japanese Meteorological Agency. The JRA55do forcing (Tsujino et. al 2018) is a corrected version specifically for coupled sea ice-ocean simulations. The JRA55 and JRA55do files are 8x daily data (every 3hr) by year with the following fields: X-ward wind (wndewd; m/s), Y-ward wind (wndnwd; m/s), Specific Humidity (spchmd; kg/kg), Air Temperature (airtmp; K), Total Precipitation (ttlpcp; kg/(m2*s) ), Downward Surface Longwave (dlwsfc; W/m2), and Downward Surface Shortwave (glbrad; W/m2). As a result, there is no need for monthly files or cloud fraction when using the JRA55 or JRA55do forcing. Five years (2005-2009) of forcing data are available. If you publish a paper using the JRA55 or JRA55do dataset please be sure to cite the appropriate paper.

Kobayashi, S., Y. Ota, Y. Harada, A. Ebita, M. Moriya, H. Onoda, K. Onogi, H. Kamahori, C. Kobayashi, H. Endo, K. Miyaoka, K. Takahashi The JRA-55 reanalysis: general specifications and basic characteristics J. Meteor. Soc. Jpn, 93 (2015), pp. 5-48. https://doi.org/10.2151/jmsj.2015-001

Tsujino, H., S. Urakawa, H. Nakano, R.J. Small, W.M. Kim, S.G. Yeager, et al. (2018). JRA‐55 based surface dataset for driving ocean–sea‐ice models (JRA55‐do). Ocean Modelling. https://doi.org/10.1016/j.ocemod.2018.07.002

FTP from the command line

The file for generating 50 years of gx1 forcing data is available from an anonymous FTP. You can click the URL listed above or access the file from the command line using the following commands:

   $ ftp ftp.cgd.ucar.edu

   $ Name: [anonymous]

   $ Password: [user's email address]

   $ cd /archive/Model-Data/CICE/

Then use standard ftp commands to obtain the relevant files from these subdirectories.