Analysis of the concurrent conditions of floods and sea storms: A case study of crotone, italy

The considerable anthropogenic pressure that has occurred since the second half of the last century has increased the vulnerability of coastal areas to the effects of natural events such as floods and sea storms, especially if these events occur simultaneously. This paper analyses the conditions that favour the concurrence of floods and sea storms through a case study near Crotone, a city in southern Italy on the Ionian Sea. The study area has a coastal extension of about 34 km, is characterized by typical rivers called “fiumare” and has been hit by several events of concurrent floods and sea storms. The conditions that favour the concurrence of floods and sea storms are mainly related to geomorphologic and climatic factors. Among these latter factors, atmospheric pressure is very important. Indeed the formation of low-pressure areas is the cause of atmospheric disturbances which can affect both the sea and the coast causing heavy rains and intense sea storms. The analysis was divided into two phases. In the first, the concurrence between floods and sea storms was verified. In the second phase, the possible correlations between the main factors involved were identified: the rainfall heights, the maximum significant wave heights and the atmospheric pressure variations observed during each atmospheric disturbance. The analysis showed that the rainfall heights and the maximum significant wave heights, that are both generally independent factors, are related to a common factor, the atmospheric pressure. This result is useful in predicting concurrent events. Indeed, by predicting atmospheric pressure variations, it is possible to estimate the expected rainfall height and the expected maximum significant wave height. The methodology described in this paper can be extended to other areas with geomorphologic and climatic characteristics that are similar to those of Crotone.