ECCO V4r4 (LLC90) grid geometry + 2010 monthly and snapshot fields (for sectionate, regionate, xgcm, xbudget, and xwmt examples)

A small subset of NASA's ECCO Version 4 Release 4 (V4r4) ocean state estimate, redistributed here only to make example notebooks for open-source software reproducible without a NASA Earthdata login — the sectionate and regionate example notebooks, a port of the xgcm ECCOv4 heat-budget tutorial, and the xwmt water-mass-transformation examples (full heat / salt / mass budgets) on the native V4r4 grid. All fields are on the native Lat-Lon-Cap 90 (LLC90) grid: 13 tiles x 90 x 90, 50 levels, for the year 2010. Relationship to the NASA PO.DAAC originals. The data values are identical to the granules distributed by NASA PO.DAAC. The only modifications are: (1) temporal selection — the twelve months of 2010 (January–December), and for the two snapshot collections the 13 month-boundary instants 2010-01-01 through 2011-01-01; and (2) per-collection concatenation (new in v3.0.0) — each collection's monthly or snapshot granules are concatenated along time into a single file per collection, to stay within Zenodo's 100-file limit. No values are altered by the concatenation; every output file carries source_granules and history global attributes recording the original NASA filenames, and each per-time slice was verified bit-exact against its source granule. Original NetCDF global attributes (including source DOIs) are preserved. One derived (non-PO.DAAC) field. GEOTHERMAL_FLUX_... is the time-invariant ECCO V4r4 geothermal heat-flux model input (geothermalFlux.bin from the ECCO v4 Python Tutorial), converted from the compact LLC layout to the standard 13-tile (tile, j, i) orientation using ecco_v4_py; global integral 34.0 TW. Changes since v2.0.0. Added the collections needed to close the salt and mass budgets (the heat budget was already present): three-dimensional salinity fluxes, ocean and sea-ice surface freshwater fluxes, Gent-McWilliams bolus velocities, temperature/salinity and sea-surface-height snapshots (for the Eulerian-tendency terms), and the geothermal heat-flux input. All collections (the four already in v2.0.0 and the new ones) were consolidated to one file per collection, concatenated along time, so the record fits Zenodo's 100-file limit. Contents (one file per collection; please cite the original NASA source datasets, not this mirror): GRID_GEOMETRY_... ECCO Geometry Parameters for the llc90 Native Model Grid 10.5067/ECL5A-GRD44 OCEAN_TEMPERATURE_SALINITY_mon_mean_2010_... Ocean Temperature and Salinity – Monthly Mean 10.5067/ECL5M-OTS44 OCEAN_3D_VOLUME_FLUX_mon_mean_2010_... Ocean Three-Dimensional Volume Fluxes – Monthly Mean 10.5067/ECL5M-3VF44 OCEAN_3D_TEMPERATURE_FLUX_mon_mean_2010_... Ocean Three-Dimensional Potential Temperature Fluxes – Monthly Mean 10.5067/ECL5M-3TF44 OCEAN_AND_ICE_SURFACE_HEAT_FLUX_mon_mean_2010_... Ocean and Sea-Ice Surface Heat Fluxes – Monthly Mean 10.5067/ECL5M-HEA44 OCEAN_3D_SALINITY_FLUX_mon_mean_2010_... Ocean Three-Dimensional Salinity Fluxes – Monthly Mean 10.5067/ECL5M-3SF44 OCEAN_AND_ICE_SURFACE_FW_FLUX_mon_mean_2010_... Ocean and Sea-Ice Surface Freshwater Fluxes – Monthly Mean 10.5067/ECL5M-FRE44 OCEAN_BOLUS_VELOCITY_mon_mean_2010_... Gent-McWilliams Ocean Bolus Velocity – Monthly Mean 10.5067/ECL5M-BOL44 OCEAN_TEMPERATURE_SALINITY_snap_2010_... Ocean Temperature and Salinity – Snapshot 10.5067/ECL5S-OTS44 SEA_SURFACE_HEIGHT_snap_2010_... Sea Surface Height – Snapshot 10.5067/ECL5S-SSH44 GEOTHERMAL_FLUX_... ECCO V4r4 geothermal heat-flux model input (not a PO.DAAC dataset; see README) — Each source dataset shares the ECCO Consortium author list, e.g.: ECCO Consortium, Fukumori, I., Wang, O., Fenty, I., Forget, G., Heimbach, P., & Ponte, R. M. (2021). <Dataset Title> (Version 4 Release 4). PO.DAAC, CA, USA. <DOI>. Please also cite the methodology paper: Forget, G., Campin, J.-M., Heimbach, P., Hill, C. N., Ponte, R. M., & Wunsch, C. (2015). ECCO version 4: an integrated framework for non-linear inverse modeling and global ocean state estimation. Geoscientific Model Development, 8, 3071–3104. https://doi.org/10.5194/gmd-8-3071-2015 Produced by the ECCO Consortium and distributed by NASA's Physical Oceanography Distributed Active Archive Center (PO.DAAC). This redistribution is not endorsed by NASA. NASA EOSDIS data are not copyrighted and are released into the public domain; this record is dedicated to the public domain under CC0 1.0.