GNGTS 2016 - Atti del 35° Convegno Nazionale

290 GNGTS 2016 S essione 2.1 with resolutions of 0.01°C and 0.01% respectively, were operative from May 2016 at about a depth of two meters. The sensors were installed to verify the influences of temperature and humidity on data collected from a gamma detector, together with air temperature and humidity. Furthermore, to verify if any possible surface temperature increase due to an increase in heat flux. Fig. 1 describes the behaviors of the gamma ray detector, underground temperature and humidity from about two weeks before the main Amatrice event, indicated by a vertical red line. No significant air radioactivity, and underground temperature and humidity changes were observed. For what concerns vertical air conductivity measured in 8 stations, its variations at different frequencies were sampled far from the power electrical distribution harmonics. An example recorded at the Fermo Station from about two weeks before the Amatrice earthquake is reported in Fig. 2 top. A set of perturbations occurred between August 17 and 19, 2016, and one peak occurred about seven hours before the main event indicated by a vertical red line. A thorough comparison of vertical electrical conductivity with other meteorological variables is necessary to exclude the presence of influences from the electrodynamics of the atmosphere. Electric field harmonics from the electrical power distribution were also monitored to detect variations linked to variations of dispersion currents through the ground. Fig. 2 middle, shows the fifth harmonic from about two weeks before the main shock of Amatrice evidencing strong variations between August 17 and 19, 2016, and then followed by a marked increase in daily oscillation starting from August 22, 2016. VLF radio waves are sampled at each of the CIEN Fig. 1 – Air gamma count, underground temperature and humidity recorded from the Fermo Station after the August 10, 2016.