ECCO Version 4: Fifth Release (1992-2019) [ECCO v4r5] These are the variables in the ECCO v4r5 output that can be accessed as snapshots on the native LLC90 grid. Snapshots are available at daily intervals (0Z time). ShortName Variable Name Description (units) ECCO_L4_OCEAN_BOTTOM_PRESSURE_LLC0090GRID_SNAPSHOT_V4R5 OBP Ocean bottom pressure, excluding global mean atmospheric pressure, given as equivalent water thickness. This is suitable for comparisons with GRACE data products. (m) OBPGMAP Ocean bottom pressure, includes global mean atmospheric pressure, given as equivalent water thickness. This is suitable for comparisons with ocean bottom pressure gauge data products. (m) PHIBOT Hydrostatic ocean bottom pressure potential anomaly, p_b/rhoConst - gH. PHIBOT is NOT corrected for global mean steric sea level changes related to density changes in the Boussinesq volume-conserving model sterGloH, and therefore should NOT be used for comparisons with ocean bottom pressure data. Instead, see OBPGMAP and OBP. (m^2/s^2) ECCO_L4_OCEAN_TEMPERATURE_SALINITY_LLC0090GRID_SNAPSHOT_V4R5 THETA Sea water potential temperature, i.e., the temperature a parcel of sea water would have if moved adiabatically to sea level pressure. (degC) SALT Sea water salinity. (1e-3, or parts per thousand) ECCO_L4_SEA_ICE_CONC_THICKNESS_LLC0090GRID_SNAPSHOT_V4R5 SIarea Fraction of ocean grid cell covered with sea-ice. (fraction between 0 and 1) SIheff Sea-ice thickness averaged over the entire model grid cell, including open water where sea-ice thickness is zero. (m) SIhsnow Snow thickness averaged over the entire model grid cell, including open water where snow thickness is zero. (m) sIceLoad Total mass of sea-ice and snow in a model grid cell averaged over model grid cell area. (kg/m^2) ECCO_L4_SEA_ICE_VELOCITY_LLC0090GRID_SNAPSHOT_V4R5 SIuice Horizontal sea-ice velocity in the +x direction at the 'u' face of the tracer cell on the native model grid. (m/s) SIvice Horizontal sea-ice velocity in the +y direction at the 'v' face of the tracer cell on the native model grid. (m/s) ECCO_L4_SEA_SURFACE_HEIGHT_LLC0090GRID_SNAPSHOT_V4R5 SSH Dynamic sea surface height, also known as ocean dynamic sea level. The local height of the sea surface above the geoid plus a correction due to atmosphere pressure loading, the inverse barometer (IB) correction. SSH is suitable for comparisons with altimetry sea surface height data products that apply the IB correction. (m) SSHNOIBC The local height of the sea surface relative to the geoid. SSHNOIBC does not include the inverted barometer (IB) correction, and is suitable for comparisons with altimetry sea surface height data products that do NOT apply the inverse barometer (IB) correction. (m) SSHIBC The static displacement of the sea surface due to atmosphere pressure loading, known as the inverse barometer (IB) correction. (m) ETAN Model sea level anomaly, without corrections for global mean density (steric) changes, inverted barometer effect, or volume displacement due to submerged sea-ice and snow. (m)