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Between the evening of October 23rd and the evening of October 24th 2017, a sea storm hit the city of Bari, along the Adriatic coast, in the south of Italy, causing widespread damages. Due to the absence of direct observations of wave characteristics, the present paper is aimed to (i) compare the development of the occurred sea storm as hindcasted by '84 method with the predictions by atmosphere-ocean numerical models and satellite observations and (ii) estimate the most reliable value of the significant wave height, Hs, at the peak of the sea storm, with its associated return period. As a result, the '84 showed the better agreement with the satellite observations in determining the value of Hs at the peak of the sea storm, compared with the predictions by more sophisticated atmosphere-ocean numerical models. In particular, the obtained value of Hs, equal to 6.58 m, makes the investigated sea storm an exceptional event. [ABSTRACT FROM AUTHOR]

Summary: Previous observations on some natural river networks showed the similar values of the support fractal dimension and the information entropy in basins having similar source rocks. In the present work, lithologic control on river network multifractality is investigated through the reconstruction of the spectra belonging to two classes of different lithology: the plutonic-metamorphic class and the coherent sedimentary one. Two computational methods of the generalised fractal dimensions and multifractal spectra are illustrated and applied to river networks of the Calabria region (Southern Italy). It is shown that an increment of both the fractal dimensions and the Lipschitz-Hölder exponents of singularity occurs when passing from a coherent sedimentary to a plutonic-metamorphic river network. The importance of this finding emerges from the direct link between flood hydrographs and multifractal spectra, as expressed in the Multifractal Instantaneous Unit Hydrograph (MIUH): the increment of the multifractal parameters produces an increment of the flood peaks. [Copyright &y& Elsevier]

Abstract: This work concerns a numerical estimation of the generalised fractal dimension of six river networks in Southern Italy, extracted from digitised maps on a 1:25,000 scale. The estimation is carried out through the method introduced by Pawelzik and Schuster, based on an extension of the correlation integral by Grassberger and Procaccia. We analysed the spectra of the generalised dimensions D q and the multi-fractal spectra f(α). The results are in agreement with the ones previously obtained through the use of standard box-counting techniques: they indicate that the investigated river networks are multi-fractal structures, with support dimensions ranging between 1.7 and 1.9, and appear not to be plane-filling sets. In the case of the Corace river, the multi-fractal spectrum of the whole river network approaches the envelope of the spectra of substructures corresponding to different hortonian stream orders. [Copyright &y& Elsevier]