CoAuthors

Denise Dettmering (DGFI-TUM, Germany); Christian Schwatke (DGFI-TUM, Germany); Marcello Passaro (DGFI-TUM, Germany); Florian Seitz (DGFI-TUM, Germany)

The recently developed and published EOT20 model provides global estimations of ocean tides from multi-mission satellite altimetry using residual tidal analysis. Utilising advances in coastal altimetry, such as the use of the ALES retracker, FES2014 as an updated reference tide model and improved coastal line representation, EOT20 attempts to provide improved estimations of ocean tides in the coastal region. The model provides the amplitude and phase of seventeen tidal constituents on a global 0.125-degree grid. The resultant model is compared to in-situ observations obtained from tide gauges taken from the updated TICON dataset and ocean bottom pressure sensor data as well as through gridded sea level variance analysis of satellite altimetry data.

EOT20 showed a reduction in root-mean-square (RMS) error for the eight major tidal constituents compared to the predecessor, EOT11a, with a major reduction in error compared to tide gauges seen in the coastal region. When compared to other global ocean tide models, EOT20 remains consistent with other models in the open ocean and shelf regions with the largest improvements being seen in the coastal region particularly in the M2 tidal constituent.

Overall, when used as the ocean tide correction EOT20 shows a reduction in gridded sea-level variance compared to both EOT11a and FES2014. This was particularly seen in the coastal regions, where a reduction in sea-level variance was seen closer to the coast when using EOT20 as the tidal correction. In this presentation, the developed EOT20 model as well as the validation of the model will be presented and discussed.