Analysis of Thermal Anomalies in Volcanic Areas Using Multiscale and Multitemporal Monitoring: Vulcano Island Test Case

Abstract

Surface temperatures derived by 208 ASTER and L8 satellite imagery were analysed to test multiscale and multitemporal capability through available sets of thermal data to support the volcanic monitoring of Vulcano Island in Italy. The analysis of thermal historical series derived by ASTER and L8 shows that two are the main thermally active areas: La Fossa crater and the mud pool of Fangaia. In this work we aimed to assess the correlation between the satellite-retrieved temperatures with those measured during the daytime ground field campaign conducted within the same time period and, in particular cases, simultaneously. Moreover, nighttime data acquired by an airborne and field campaign were processed with the same methodology applied to satellite data for a multiscale approach verification. Historical meteorological data acquired from a weather station were also considered. Statistically significant correlations were observed between nighttime acquisitions and meteorological data. Correlations were also significant for temperature measured during the airborne campaign, while differences up to 50% with daytime acquisition during the ground field campaigns were observed. The analysis of the results suggests that within nighttime data acquisition, differences between satellite-derived temperatures and ground temperature measurements are considerably reduced; therefore nighttime data acquisition is recommended to detect thermal anomalies.

Surface Temperature Multiscale Monitoring by Thermal Infrared Satellite and Ground Images at Campi Flegrei Volcanic Area (Italy)

“…Considering the nighttime data time series collected, excluding cloudy scenes, the analyzed L8 data are reported in Table 1. The estimations of surface temperature were obtained by applying the procedure described in [53] and its bibliography.…”

Cyclic Behavior in the Fumaroles Output Detected by Direct Measurement of Temperature of the Ground

“…These thermal anomalies of minor intensity usually cause ground temperature below the boiling point and reveal high diffuse heat fluxes often associated to high CO 2 fluxes of magmatic origin [12,25]. The Figure 4 show the main thermal zones inside the caldera of La Fossa, as they are remotely sensed by the satellite Landsat 8 [26]. The thermal area in Figure 4b, indicated by the white circle in the summit of the active cone "la Fossa", includes the high temperature fumaroles and the continuous monitoring sites (see Figures 2a and 3 for site locations), and other anomalous surfaces interested by diffuse gas emissions [27].…”

First Comparisons of Surface Temperature Estimations between ECOSTRESS, ASTER and Landsat 8 over Italian Volcanic and Geothermal Areas

“…The TES method cannot be applied to TIRS-L8 thermal data due to the presence of only two bands in the TIR range; thus, for this analysis, we have used a single-channel methodology which was already tested in [2,24] for retrieving LST. For TIRS-L8 data, the effects of surface emissivity are corrected using the ASTER 05 Emissivity product.…”

“…Moreover, a geothermal test site, the Parco delle Biancane (PdB) area in Tuscany, was selected in order to analyze the capability of satellite data to detect thermal anomalies in non-volcanic areas. All selected areas are characterized by high-temperature geothermal energy sources, commonly marked by thermal manifestations such as fumaroles, steaming ground, hot springs, volcanic gas vents, craters, and mud pools [1][2][3][4]. These areas must be commonly subjected to geophysical monitoring where measurements of shallow and surface temperatures may play an important role in the field of thermal monitoring.…”