Relationship between marine and coastal hazard parameters of Mediterranean cyclones

Mediterranean cyclones are often weaker and smaller than other mid-latitude cyclones that develop over open oceans. However, they have a great impact on the Mediterranean basin which is highly populated on the coasts, causing heavy precipitation, windstorms, storm surges and sea wave extremes. The marine and coastal hazard related to cyclones can be quantified with several parameters like the maximum storm surge, the maximum significant wave height and other intensity indices based on waves or sea levels. The aim of this study is to investigate the relationship between different marine and coastal hazard parameters.

In this work we consider a dataset of more then 1000 cyclones which took place in the period 1994-2020 in the Mediterranean basin. The reference dataset is provided by a composite approach that uses different detection and tracking methods, proposed by Flaounas et al. (2023). To analyse the ocean response a coupled hydrodynamic-wave numerical model is used to account for the wave-current interaction. The modelling system consists in the SHYFEM (System of HydrodYnamic Finite Element Modules) hydrodynamic model, two-way coupled with the WW3 (WAVEWATCH III) wave model. The CERRA data are used as meteorological forcing in terms of wind and mean sea level pressure. To assess the marine hazard the following parameters based on sea levels and sea waves are considered: the maximum storm surge, the maximum significant wave height, the mean cyclone influence area, the total storm wave energy, the storm power index and the storm erosion potential index. Relationship between different measures are analysed through Pearson and mutual information correlation coefficients.

First results shows a strong correlation between the maximum significant wave height and the intensity indices based on waves. On the contrary there is
a weak correlation between the maximum storm surge and the intensity index based on sea levels. Other results concerning the relationship between hazard parameters will be presented. Ongoing investigations aim to include in the analysis some atmospheric features such as mean sea level pressure and wind in order to characterize the relationship between atmospheric anc ocean parameters.