Nodal Modulation of Tidal Constituents in the North Sea

Harmonic analysis of sea surface elevation is commonly performed using the f-u correction procedure, which alters the analyzed tidal constituents, based on the longitude of the lunar ascending node at a 18.61 year frequency. Measurement analysis has led us to conclude, that common nodal modulation factors are inaccurate in the shallow regions of the North Sea, due to the friction-induced generation of overtides. For this reason we applied a numerical model to quantify the nodal modulation spatially. The hereby presented data set is therefore derived from model results and includes the nodal amplitude modulation and phase lag for the North Sea on a 7,500m raster as supplemental material to Hagen, et al. (2021, to appear). This data set may be used for the manual correction of nodal modulation in modeling applications, MSL analysis and any other application regarding harmonic analysis in the North Sea region.