M. Lawless and D. Rodger – Proceedings 12th International Coastal Symposium (Plymouth, England), Journal of Coastal Research, April, 2013
Tidal flows, sea levels and currents influence coastal flood and erosion risk, flood defence design, coastal management and renewable energy production. Historically data for these variables have been obtained from tide gauge records. However, this information is limited in both time and space. Consequently, analysis and planning for sites between gauges has traditionally been established through simple interpolation techniques, thereby leading to higher levels of uncertainty than desirable. For a more reliable application to coastal and ocean engineering, a more holistic approach is required.
Initially developed as a response to the increasing threat of flooding from the sea, JBA developed a comprehensive suite of high-resolution hindcast tide-surge models for Western Europe, collectively called the European Tidal Database. The models within this suite simulate every tide that has occurred around the coast of the UK, Ireland and Western Europe for the 45 years between 1957 and 2002. In addition to the tidal forcing, the models are also forced at the surface by windstress and atmospheric pressure data interpolated from the European Centre for Medium Range Weather Forecasts (ERA-40), simulating surge affects. The output from the models can be visualised as a high resolution virtual tide gauge record, including a 45-year record of tide, current and surge levels for more than 20,000 closely spaced points along our coasts, estuaries and tidal rivers.
This model data provides unprecedented long-term historical information that can be used to evaluate exposure to coastal flood risk at any location more accurately than previous approaches. Currently the models within the UK Tidal Database are being used to determine surge relationships between real-time gauges for the purposes for flood warning and extremes analysis, although its application is planned to span a range of additional coastal engineering disciplines. In particular, the results of the model could be used to determine the potential power of harnessing tidal flows at any location by determining the energy returns that would have been achieved had devices been in the sea over the last 45 years. This paper described the modeling that underpins the European Tidal Database and discusses its broader applications.