Numerical modelling of coastal morphology is a complex and sometimes
unrewarding exercise and often not yielding tangible results. Typically, the
underlying drivers of morphology are not properly accounted for in numerical
models. Such inaccuracies combined with a paucity of validation data create a
difficulty for coastal planners/engineers who are required to interpret such
morphological models to develop coastal management strategies. This study
develops an approach to long term morphological modelling of a barrier beach system
that includes the findings of over 10 years of coastal monitoring on a dynamic
coastal system. The novel approach to predicting the long term evolution of the
area combines a mix of short term hydrodynamic monitoring and long term
morphological modelling to predict future changes in a breached barrier system.
A coupled wave, wind, hydrodynamic and sediment transport numerical model was
used to predict the coastal evolution in the dynamic barrier beach system of
Inner Dingle Bay, Co. Kerry, Ireland. The modelling approach utilizes the
schematisation of inputs to reflect observed trends. The approach is subject to
two stages of validation both quantitative and qualitative. The study
highlights the importance of considering all the parameters responsible for
driving coastal evolution and the necessity to have long term monitoring
results for trend based validation.
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