Lowest Astronomical Tide in the North Sea derived from a vertically referenced shallow water model, and an assessment of its suggested sense of safety

In this study, LAT will be modeled relative to a geoid, after which the ellipsoidal heights of LAT will be obtained by adding geoid heights to the modeled LAT values. The use of a geoid instead of MSL has the advantage that the former can be realized everywhere and does not leave a gap along the coast as satellite radar altimetry does. Modeling LAT relative to a geoid is realized by i) the explicit modeling of the average meteorological and steric conditions as required by the definition of LAT and ii) referencing the hydrodynamic model to the chosen geoid. Another advantage of this approach is that it is conceptually consistent; unlike MSL, both the geoid and the model’s reference surface are equipotential surfaces. Moreover, this approach allows for the inclusion of temporal variations in the definition of the average meteorological conditions. The latter reason follows from a precise interpretation of the LAT definition that the average meteorological conditions in spring and those in fall should be included separately.
Geoscience and Remote Sensing
Civil Engineering and Geosciences