Evidence of Tsallis entropy signature on medicane induced ambient seismic signals

Abstract

The link between hurricanes or typhoons and their generated ambient noise has recently become a frontier topic in the field of applied seismology. In the Mediterranean region, infrequent tropical-like cyclones, known as Medicanes or Mediterranean hurricanes, with similar characteristics with hurricanes appear, with the most recent storm occurred on September 27–30, 2018 in South Greece, which characterized by gale winds, severe precipitation, and a low pressure center, accompanied with a spiral pattern of thunderstorms. In this work, we describe the Medicane’s induced ambient seismic noise fluctuations, as recorded in seismological station along to the path of the recent Medicane, in terms of non-extensive statistical physics. We found that the Medicane’s induced ambient seismic noise increments follow the q-Gaussian distribution. This indicates that Medicane induced ambient seismic noise’s fluctuations are not random and present long-term memory effects that could be described in terms of Tsallis entropy. Our results suggest that in the Medicane system that affected the Southwest Peloponnese the q–values of the induced ambient seismic noise’s fluctuations in the Kalamata (KLMT) seismological station located in Southwest Peloponnese are q≈1.67, which corresponds to n=2 degrees of freedom system, indicating that Medicane induced ambient seismic noise fluctuations compose of two independent Gaussian random variables. For stations as that of APE (Apiranthos, Naxos island, Cyclades), where an attenuated Medicane was observed, a q≈1.57 obtained, which is similar with that observed in the KNDR (Koundoura, South West Crete) seismological station, where the Medicane appears before its main organization as intensively observed in the KLMT station. For the CHAN (Chania, West Crete ) station a q≈1.32 was observed which corresponds to about 5 degrees of freedom indicating that Medicane induced ambient seismic noise fluctuations compose of about five independent Gaussian random variables, in agreement with the week intensity of Medicane observed in Chania.