GNGTS 2015 - Atti del 34° Convegno Nazionale

GNGTS 2015 S essione 2.1 33 3. a review of signal dynamics about world wide recorded flow rate emissions of CO 2 or CH 4 gas emissions located in non volcanic areas was carried out. Greenhouse gases are represented chiefly by CO 2 while further greenhouse gases data were converted into CO 2 equivalent amounts. Cold season CO 2 emissions are significantly higher when compared to warm season and have been estimated to be about three times more abundant during cold season with respect to warm season like in the town of Firenze (Gioli et al. , 2012). ISPRA data on CO 2 equivalent gas emissions are compiled on a yearly average value and at province resolution. A data base of CO 2 gas emissions per province was thus compiled taking into account that cold season emissions are about three times more abundant with respect to warm season. Signal dynamics analysis about natural CO 2 gas emissions evidence that natural gas emissions are characterized by maximum flow rate values which are usually the double (exceptionally three times more) when compared to minimum values. Thus eventual CO 2 gas flow rate anomalies possibly due to crustal deformation processes (Heinicke et al. , 2010; Tramutoli et al. , 2013) should exceed natural and artificial background represented by human activities to be detectable. Due to relatively low values of man induced CO 2 emissions and to contemporary relatively high natural CO 2 gas emissions in the same areas some provinces of central and southern Italy could be, in principle, in condition to generate natural CO 2 gas emissions significantly higher than background value. If TIR and RETIRA signals are attributable to greenhouse natural gas emissions (Tramutoli et al. , 2013) like CO 2 and CH 4 a belt of candidate provinces suitable for eventual detection of the hypothesized phenomenon has been identified. In these areas crustal deformative processes could induce possible TIR and RETIRA anomalies eventually shaped by wind dynamics and by further climatological and topographic factors. In order to better understand possible tropospheric CO 2 dynamic features the GAW-WDCGG three stations were considered: Mt. Cimone (northern Apennines), Plateau Rosa (western Alps) and Sonnblick (Austria). PCA analysis was carried out on time series recorded in the period 2000-2014. PC1 is probably related to common meteoclimatic factors while PC2 evidences local artificial and natural CO 2 emission features. These findings should be considered as preliminary since no complete statistical analysis of the whole data set was carried out. Anyway CO 2 analyzed data evidence possible not man induced fluctuations. This finding corroborate the idea of Tramutoli et al. (2013) about natural CO 2 fluctuations possibly induced by eventual geodynamic factors. Ground based temperature data processing. Qin et al. (2012) published that a possible thermal anomaly was detected by TIR satellite based sensors in concomitance with the 2012 Emilia seismic sequence. Tramutoli et al. (2015) report that RETIRA index anomalies were recorded before the 2012 Emilia seismic sequence. To better understand if an eventual greenhouse gas emission dependent thermal anomaly was observed a ground based meteoclimatic data set was analyzed. In particular the ERG5 temperature data base (see also Antolini et al. , 2015) was considered. Minimum temperature data were considered and analyzed by PCA techniques. In particular PC1 evidence a constant temperature increase in the plain areas. PC2 evidence that further temperature increase were observed in the period 2005-2012 in the hilly areas of the region at an altitude of about 100-500 m. In the same area most relevant deep originated CH 4 gas emissions of northern Apennines are located. Possible contributions of deep originated CH 4 to local greenhouse temperature anomalies are not escluded while CH 4 emissions located in the plain areas should be considered not sensitive to eventual geodynamic phenomena since generated at a 50 m depth. The complete statistical analysis of the whole data set including also original data not included in the ERG- 5 data base will allow more definitive conclusions. Conclusions. Water level analysis of Po Plain groundwaters evidences that a long term trend started in the 1912-1933 period well before man induced perturbations on wellhead values was identified. The long term trend is monotonic in the eastern side of the region while a V shaped trend was detected in the western side of the region. During the periods of increasing water