Accessing Raw Data (raw_data_access)

CrocoDash uses several datasets to setup the model. Data can be gathered directly from public datasources (including the CESM inputdata svn repository) or through helper functions in the CrocoDash Raw Data Access module. The Raw Data Access Module is an expandible, verifyable, object-oriented module with access functions to raw datasets used in CrocoDash. This document explains what it is and what you can do to add more to it, if you would like to!

Specific datasets can either be accessed directly through the data access module or be chosen by adding arguments to the case.configure_forcings function. Check out the demo here.

Users can check if datasets are accessible at this link.

Please see below for available datasets.

Data Product Registry

Product	Description	Link
cesm_pop_output	CESM ocean output (POP2 grid) for use as IC and OBC, including CESM-HR FOSI and CESM2 Large Ensemble (LENS2)	https://gdex.ucar.edu/datasets/d267000/
cesm_mom_output	Native MOM6 output (full history/diagnostic files, or diag_table-extracted cross-section slices) for use as IC/OBC forcing - e.g. for nesting a child domain inside an outer/parent MOM6 run.	https://mom6.readthedocs.io/en/main/api/generated/pages/Diagnostics.html
cesm-ww3-jra	Full 2D wave spectra E(f, theta) for WW3 open boundaries, read out of a JRA-forced global wave-only CESM/WW3 run’s 6-hourly netCDF restarts on GLADE – boundary waves driven by the same JRA winds as the regional case’s own interior, with no network access or credentials required. The default database is the 1-degree wi_jra.glo1p0.001 run (useful record from ~2018-12-01, after spin-up).	CROCODILE-CESM/CrocoDash
cice_restart	Global CICE restart file, index-subset to a regional domain’s bounding box for use as a cold-start initial condition.	https://escomp.github.io/CICE/versions/master/html/user_guide/ug_case_settings.html
tpxo	TPXO (TOPEX/POSEIDON Global Tidal Ocean I think) is a public tidal model dataset	https://www.tpxo.net/global
cesm inputdata	The CESM Input SVN repo holds all files CrocoDash exposes publicly themselves at the following repo link	https://svn-ccsm-inputdata.cgd.ucar.edu/trunk/inputdata/ocn/mom/croc
era5_wave_spectra	ERA5’s true 2D wave energy-density spectrum E(f, theta) (ECMWF param 251.140, wave stream) from Copernicus CDS’s reanalysis-era5-complete dataset – NOT the bulk/integrated wave stats (significant height, mean direction, mean period) available on reanalysis-era5-single-levels.	https://cds.climate.copernicus.eu/datasets/reanalysis-era5-complete
gebco	GEBCO (General Bathymetric Chart of the Ocean) is a public dataset of global ocean bathymetry	https://www.gebco.net/data_and_products/gridded_bathymetry_data/#global
glofas	GLOFAS (Global Flood Awareness System) is a public river discharge/runoff Product	https://ewds.climate.copernicus.eu/datasets/cems-glofas-historical?tab=download
glorys	GLORYS (Global Ocean Physics Reanalysis) is a public dataset provided through the copernicus marine service.	https://data.marine.copernicus.eu/product/GLOBAL_MULTIYEAR_PHY_001_030/description
reference_ocean	Fast, deterministic synthetic ocean IC/OBC data (temperature, salinity, SSH, currents) for testing and demos – no network or campaign-storage access required.	n/a
reference_ice	Fast, deterministic synthetic CICE forcing (ice concentration/volume/surface temp and a small drift velocity) for testing and demos – generates its own grid, no real CICE restart/grid file required. Exercises the CrocoDash regrid path only: it writes a single category (ncat=1) and five variables, where CICE needs ncat=5 plus the rest of the restart state (vsnon, trcrn, …), so CICE cannot actually start from the file this produces. Use ‘cice_restart’ against a real global restart for a runnable case.	n/a
reference_waves	Fast, deterministic synthetic WW3 boundary wave spectra (JONSWAP-shaped frequency spectrum, cosine-2s directional spreading) for testing and demos – no CDS/network access required.	n/a
seawifs	SEAWIFS is a Chlorophyll Dataset for MOM6	https://oceandata.sci.gsfc.nasa.gov/getfile/SEASTAR_SEAWIFS_GAC.19980201_20100228.L3m.MC.CHL.chlor_a.9km.nc
srtm	SRTM15+ is a global 15 arc-second resolution bathymetry/topography dataset compiled from SRTM land topography and satellite-derived ocean bathymetry.	https://topex.ucsd.edu/WWW_html/srtm15_plus.html

CrocoDash Data Access Module

CrocoDash has a data_access module for accessing various datasets. Please see below for a table of available methods.

Data Access Registry

Product	Function	Type	Description
cesm_pop_output	get_cesm_single_variable_data	python	Gets CESM single-variable-per-file (tseries) ocean data from a given path (by default a POP-MARBL run) — the standard CESM postprocessed output organization, one variable per file series with the date range encoded in the filename. Covers both CESM-HR FOSI and CESM2-LENS2 (pass member to select an ensemble member).
cesm_mom_output	get_mom6_output_data	python	Reads native MOM6 output (full history/diagnostic files, or diag_table-extracted cross-section slices) from any directory and subsets to a lat/lon bounding box — e.g. for nesting a child domain inside an outer/parent MOM6 run.
cesm_mom_output	get_mom6_single_variable_data	python	Gets native MOM6 output that’s organized in the CESM single-variable-per-file (tseries) convention instead of one multi-variable file per region/timestep — some parent runs post-process their history output this way before archiving it.
cesm-ww3-jra	get_cesm_ww3_jra_spectra	python	Reads 2D wave spectra for a boundary window out of a global CESM/WW3 run’s 6-hourly netCDF restarts, converting WW3’s stored action density to variance density E(f, theta) and writing a NetCDF file with real (time, latitude, longitude, frequency, direction) dims – the same shape era5.py’s decoded product has, so the rest of the WW3 OBC pipeline is unchanged. Needs no credentials, only read access to the run directory.
cice_restart	get_cice_restart_subset	python	Reads a global CICE restart file and its companion grid file, locates the (nj, ni) index window covering the requested lat/lon bounding box on the grid’s T-point coordinates, and writes the restart subset over that window. Point restart_path at a global CICE restart (.cice.r..nc) and grid_path at its companion CICE grid file, e.g. /glade/campaign/cesm/community/omwg/grids/tx2_3v3_grid.nc for the tx2_3v3 grid. This isn’t a real dated forcing product yet – a restart is a single snapshot with no time axis of its own, and it is written out as-is, with no time axis added and dates ignored. variables defaults to keeping every variable in the restart, since which state variables exist depends on compile-time CICE options (tracer/layer counts) that this function has no way to know in advance.
era5_wave_spectra	get_era5_2d_spectra	python	Gets ERA5’s true 2D wave spectra via the cdsapi package from CDS’s reanalysis-era5-complete (MARS-style) dataset, decodes the returned GRIB (see module docstring for why cfgrib can’t do this directly), and writes a clean NetCDF file with real (time, latitude, longitude, frequency, direction) dims. Requires a cdsapi config pointed at cds.climate.copernicus.eu with reanalysis-era5-complete access – NOT the ~/.cdsapirc EWDS config GLOFAS uses. To get a key: (1) register a free account at cds.climate.copernicus.eu, (2) open reanalysis-era5-complete’s dataset page and accept its license under ‘Terms of use’, (3) copy your UID and API key from your CDS profile page, (4) write them to a config file (default ~/.cdsapirc_era5, overridable via the cdsapi_rc_path arg below) in the form: url: https://cds.climate.copernicus.eu/api key: <UID>:<API-key> If ~/.cdsapirc already points at a different CDS-family service (e.g. EWDS, used by GLOFAS) and $CDSAPI_RC isn’t set, this falls back to cdsapi_rc_path automatically; set cdsapi_rc_path to wherever your real CDS config actually lives (via configure_forcings’s ww3_obc_function_overrides) if that’s not ~/.cdsapirc_era5.
gebco	get_gebco_data_with_python	python	Python request for global bathymetry data
gebco	get_gebco_data_script	script	get script to download global bathymetry data
glofas	get_global_data_with_python	python	Gets glofas raw data through the cdsapi package
glofas	get_processed_global_glofas_script_for_cli	script	Generates bash script for access to CESM Inputdata processed glofas data
glorys	get_glorys_data_from_rda	python	Gathers GLORYS data from RDA on computers with access to glade/rda
glorys	get_glorys_data_from_cds_api	python	Python request with copernicusmarine api
glorys	get_glorys_data_script_for_cli	script	Generates bash script for direct CLI run with the copernicusmarine package
reference_ocean	get_reference_ocean_data	python	Generates a synthetic ocean dataset over the requested bbox/dates: temperature warm at the equator and decaying exponentially with depth, near-constant salinity, a smooth sinusoidal sea-surface height, and small sinusoidal currents. One value per day.
reference_ice	get_reference_ice_data	python	Generates a synthetic single-category CICE-shaped dataset over the requested bbox/dates: its own regular tlon/tlat/ulon/ulat mesh (no real CICE grid file needed), ice concentration tapering linearly from the bbox’s poleward edge to zero at its equatorward edge, matching ice volume/surface temp, and a small drift velocity.
reference_waves	get_reference_wave_spectra	python	Generates a synthetic multi-station 2D wave spectrum (JONSWAP frequency shape, cosine-2s directional spreading) over the requested bbox/dates, in the same (time, latitude, longitude, frequency, direction) shape the real decoded ERA5 product uses.
seawifs	get_global_seawifs_script_for_cli	script	Generates bash script for direct CLI access to chlorophyll data (No Package Required)
seawifs	get_processed_global_seawifs_script_for_cli	script	Generates bash script for direct CLI access to processed chlorophyll data (No Package Required)
srtm	get_srtm_data_with_python	python	Python download of the SRTM15+ global bathymetry NetCDF file
srtm	get_srtm_data_script	script	Bash script to download the SRTM15+ global bathymetry NetCDF file

Want to add more?

Interested in adding your own spin on a dataset? Maybe with alternative metadata? Check our our additional docs: Adding Raw Data Products