Abstract
Abstract
On 12 November 2019 at 21:50 UTC about 85% of the city of Venice was flooded, due to the sea level height reaching 189 cm – the second largest value ever recorded there. Both the operational modeling system and the machine learning system underestimated the event by about 40 cm. In order to explain the underestimation, the sea level data recorded in the area were subjected to the decomposition method that had been gradually developed at the Andrija Mohorovičić Geophysical Institute over the last forty or so years. The procedure revealed eight phenomena contributing to the sea level maximum: vertical land motion, sea level rise, variable annual change, surge caused by planetary atmospheric waves, tide, storm surge, meteotsunami and wind set-up inside the lagoon. It turned out that a combined contribution of the last two phenomena was almost equal to the difference between observed sea level height and forecasted/hindcasted values. Consequently, the difference was related to a secondary atmospheric depression, which had caused both meteotsunami and wind set-up inside the lagoon but was not adequately captured by the operational modeling system nor was it allowed for by the machine learning system. Since the decomposition method proved to be useful in the Adriatic Sea, it is expected that the method could be applicable in other basins around the world if they are prone to strong and multifaceted atmospheric forcing.
Publisher
Research Square Platform LLC
Reference56 articles.
1. Storm surge forecasting in the Adriatic Sea by means of a two-dimensional hydrodynamical numerical model;Accerboni E;Bollettino di Geofisica Teorica ed Applicata,1973
2. Sull'uso di modelli matematici idrodinamici per lo studio dell'acqua alta a Venezia;Accerboni E;Bollettino di Geofisica Teorica ed Applicata,1971
3. Tides and waves;Airy GB;Encyclopaedia Metropolitana,1845
4. Storm surge and seiche modelling in the Adriatic Sea and the impact of data assimilation;Bajo M;Quarterly Journal of the Royal Meteorological Society,2019
5. Sesse dell’alto Adriatico con particolare riguardo al Golfo di Trieste;Caloi P;Memorie, R. Comitato Talassografico Italiano,1938