Journal cover Journal topic
Ocean Science An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/os-2018-63
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
30 May 2018
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Ocean Science (OS).
Storm surge forecasting: quantifying errors arising from the double-counting of radiational tides
Joanne Williams1, Maialen Irazoqui Apecechea2, Andrew Saulter3, and Kevin J. Horsburgh1 1National Oceanography Centre, Joseph Proudman Building, 6 Brownlow St, Liverpool, UK
2Deltares, Delft, Netherlands
3Met Office, Fitzroy Road, Exeter, UK
Abstract. Tide predictions based on tide-gauge observations are not just the astronomical tides, they also contain radiational tides – periodic sea level changes due to atmospheric conditions and solar forcing. This poses a problem of double-counting for operational forecasts of total water level during storm surges. In some surge forecasting, a regional model is run as tide-only, with astronomic forcing alone; and tide-and-surge, forced additionally by surface winds and pressure. The surge residual is defined to be the difference between these configurations and is added to the local harmonic predictions from gauges. Here we use the Global Tide and Surge Model based on Delft-FM to investigate this in the UK and elsewhere, quantifying the weather-related tides that may be double-counted in operational forecasts. We show that the global S2 atmospheric tide is captured by the tide-surge model, and observe changes in other key constituents, including M2. We also quantify the extent to which the Highest Astronomical Tide, which is derived from tide predictions based on observations, may contain weather-related components.
Citation: Williams, J., Irazoqui Apecechea, M., Saulter, A., and Horsburgh, K. J.: Storm surge forecasting: quantifying errors arising from the double-counting of radiational tides, Ocean Sci. Discuss., https://doi.org/10.5194/os-2018-63, in review, 2018.
Joanne Williams et al.
Joanne Williams et al.
Joanne Williams et al.

Viewed

Total article views: 208 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
185 21 2 208 4 4

Views and downloads (calculated since 30 May 2018)

Cumulative views and downloads (calculated since 30 May 2018)

Viewed (geographical distribution)

Total article views: 208 (including HTML, PDF, and XML)

Thereof 208 with geography defined and 0 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 19 Jun 2018
Publications Copernicus
Download
Short summary
Tide predictions based on tide-gauge observations are not just astronomical tides, they also contain periodic sea level changes due to the weather. Forecasts of total water level during storm surges add the immediate effects of the weather to the astronomical tide prediction, so must be careful not to double-count these effects. We calculate how much double-counting may affect these forecasts, and also how much of the Highest Astronomical Tide may also be due to recurrent weather patterns.
Tide predictions based on tide-gauge observations are not just astronomical tides, they also...
Share