Seismic evidence of the COVID-19 lockdown measures a case study from eastern Sicily (Italy)

摘要

During the COVID-19 pandemic, most countries put in placesocial interventions, restricting the mobility of citizens, to slow thespread of the epidemic. Italy, the first European country severely impactedby the COVID-19 outbreak, applied a sequence of progressive restrictions toreduce human mobility from the end of February to mid-March?2020. Here, weanalysed the seismic signatures of these lockdown measures in denselypopulated eastern Sicily, characterized by the presence of a permanentseismic network used for earthquake and volcanic monitoring. We emphasizehow the anthropogenic seismic noise decrease is visible even at stationslocated in remote areas (Etna and Aeolian Islands) and that the amount of thisreduction (reaching ～?50?%–60?%), its temporal pattern andspectral content are strongly station-dependent. Concerning the latter, weshowed that on average the frequencies above 10?Hz are the most influencedby the anthropogenic seismic noise. We found similarities between thetemporal patterns of anthropogenic seismic noise and human mobility, asquantified by the mobile-phone-derived data shared by Google, Facebook andApple, as well as by ship traffic data. These results further confirm howseismic data, routinely acquired worldwide for seismic and volcanicsurveillance, can be used to monitor human mobility too.