Created: May 31, 2023

Proposer: Fernando Manzano on behalf of the Copernicus Marine In Situ TAC Sea Level Reprocessed product Team

Proposed Date: 2023-05-30

Change Date: May 31, 2023, 1 p.m.

Term: **tidal_sea_surface_height_above_reference_datum**

Unit: m

Unit ref: ULAA

AMIP:

GRIB:

"Sea surface height" is a time-varying quantity. "Height_above_X" means the vertical distance above the named surface X, in this case above an arbitrary reference datum. The altitude of the datum should be provided in a variable with standard name tidal_sea_surface_height_above_reference_datum. The tidal component of sea surface height describes the predicted variability of the sea surface due to astronomic forcing (chiefly lunar and solar cycles) and shallow water resonance of tidal components; for example as generated based on harmonic analysis, or resulting from the application of harmonic tidal series as boundary conditions to a numerical tidal model.

Change Date: Oct. 12, 2023, 3:48 p.m.

Term: **tidal_sea_surface_height_above_reference_datum**

Unit: m

Unit ref: ULAA

AMIP:

GRIB:

"Sea surface height" is a time-varying quantity. "Height_above_X" means the vertical distance above the named surface X, in this case above an arbitrary reference datum. The tidal component of sea surface height describes the predicted variability of the sea surface due to astronomic forcing (chiefly lunar and solar cycles) and shallow water resonance of tidal components; for example as generated based on harmonic analysis, or resulting from the application of harmonic tidal series as boundary conditions to a numerical tidal model. The reference datum could be a geophysical surface, a height with respect to a geophysical surface, or a local benchmark attached to the land. Because the definition of the datum may vary from one place to another, spatial differences in actual tidal_sea_surface_height_above_reference_datum are not generally physically meaningful. However, local differences in this quantity over time are physically meaningful.