Coastal Impacts of Storm Gloria (January 2020) over the Northwestern Mediterranean

Abstract

Abstract. The ocean component and coastal impacts of Storm Gloria, that hit the Western Mediterranean between January 20th and 23rd 2020 are investigated with a numerical simulation of the storm surges and wind-waves. Storm Gloria caused severe damages and beat several historical records such as significant wave height or 24-h accumulated precipitation. The storm surge developed along the eastern coasts of the Iberian Peninsula reached values up to 1 m, and were accompanied by wind-waves with significant wave height up to 8 m. Along the coasts of the Balearic Islands, the storm footprint was characterised by a negligible storm surge and the impacts were caused by large waves. The comparison to historical records reveals that Storm Gloria is one of the most intense among the events in the region during the last decades and that the waves direction was particularly unusual. Our simulation permits quantifying the role of the different forcings in generating the storm surge. Also, the high spatial grid resolution down to 30 m over the Ebro Delta, allows determining the extent of the flooding caused by the storm surge. We also simulate the overtopping caused by high wind waves that affected a rocky coast of high cliffs (~ 15 m) in the eastern coast of Mallorca Island.