Altimetry-derived tide model for improved tide and water level forecasting along the European continental shelf

• Published in: Ocean dynamics Vol. 73; no. 8; pp. 475 - 491
• Main Authors: Hart-Davis, Michael G., Laan, Stendert, Schwatke, Christian, Backeberg, Björn, Dettmering, Denise, Zijl, Firmijn, Verlaan, Martin, Passaro, Marcello, Seitz, Florian
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2023; Springer Nature B.V
• Subjects: Altimetry; Atmospheric Sciences; Constituents; Continental shelves; Early warning systems; Earth and Environmental Science; Earth Sciences; Finite element method; Fluid- and Aerodynamics; Gauges; Geophysics/Geodesy; Height; Mean sea level; Modelling; Monitoring/Environmental Analysis; Ocean tides; Oceanography; Reduction; Regional development; Satellite altimetry; Satellite tracking; Sea level; Sea level rise; Tidal constituents; Tide gauges; Warning systems; Water levels; Ocean tides; Satellite altimetry; EOT; Sea level; Numerical modelling
• ISSN: 1616-7341; 1616-7228
• DOI: 10.1007/s10236-023-01560-0

With the continued rise in global mean sea level, operational predictions of tidal height and total water levels have become crucial for accurate estimations and understanding of sea level processes. The Dutch Continental Shelf Model in Delft3D Flexible Mesh (DCSM-FM) is developed at Deltares to operationally estimate the total water levels to help trigger early warning systems to mitigate against these extreme events. In this study, a regional version of the Empirical Ocean Tide model for the Northwest European Continental Sea (EOT-NECS) is developed with the aim to apply better tidal forcing along the boundary of the regional DCSM-FM. EOT-NECS is developed at DGFI-TUM by using 30 years of multi-mission along-track satellite altimetry to derive tidal constituents which are estimated both empirically and semi-empirically. Compared to the global model, EOT20, EOT-NECS showed a reduction in the root-square-sum error for the eight major tidal constituents of 0.68 cm compared to in situ tide gauges. When applying constituents from EOT-NECS at the boundaries of DCSM-FM, an overall improvement of 0.29 cm was seen in the root-mean-square error of tidal height estimations made by DCSM-FM, with some regions exceeding a 1 cm improvement. Furthermore, of the fourteen constituents tested, eleven showed a reduction of RMS when included at the boundary of DCSM-FM from EOT-NECS. The results demonstrate the importance of using the appropriate tide model(s) as boundary forcings, and in this study, the use of EOT-NECS has a positive impact on the total water level estimations made in the northwest European continental seas.