nerc.ac.uk

Radiational tides: their double-counting in storm surge forecasts and contribution to the Highest Astronomical Tide

Williams, Joanne; Irazoqui Apecechea, Maialen; Saulter, Andrew; Horsburgh, Kevin J.. 2018 Radiational tides: their double-counting in storm surge forecasts and contribution to the Highest Astronomical Tide. Ocean Science, 14 (5). 1057-1068. https://doi.org/10.5194/os-14-1057-2018

Before downloading, please read NORA policies.
[img]
Preview
Text
os-14-1057-2018.pdf
Available under License Creative Commons Attribution 4.0.

Download (5MB) | Preview
[img]
Preview
Text
SurgeForecastPaperFinal.pdf

Download (14MB) | Preview

Abstract/Summary

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 in two modes: 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 (GTSM) 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-and-surge model and observe changes in other major constituents, including M2. The Lowest and Highest Astronomical Tide levels, used in navigation datums and design heights, are derived from tide predictions based on observations. We use our findings on radiational tides to quantify the extent to which these levels may contain weather-related components.

Item Type: Publication - Article
Digital Object Identifier (DOI): https://doi.org/10.5194/os-14-1057-2018
ISSN: 1812-0792
Date made live: 09 Oct 2018 12:34 +0 (UTC)
URI: http://nora.nerc.ac.uk/id/eprint/521151

Actions (login required)

View Item View Item

Document Downloads

Downloads for past 30 days

Downloads per month over past year

More statistics for this item...