Thermal Remote Sensing for Global Volcano Monitoring: Experiences From the MIROVA System

Abstract

Thermal Remote Sensing for Volcano Monitoring volcanological community. The results presented clearly demonstrate how the open access of satellite thermal data and the sharing of derived products allow a better understanding of ongoing volcanic phenomena, and therefore constitute an essential requirement for the assessment of volcanic hazards.

Volcanic Hot-Spot Detection Using SENTINEL-2: A Comparison with MODIS–MIROVA Thermal Data Series

“…with Figure 10a). This behavior could represent an inner character of open-vent volcanoes, where an intensification in the VRP could be related to the increase in the convective dynamics in the upper portion of the magma column, inducing a rising of the magma column level and an increase in vent(s) temperature [20,75], while retaining a hot area quite constant.…”

“…It gives a quantification of the Volcanic Radiative Power (heat flux, in Watt) through a hybrid algorithm based on MIR radiance data analysis (~3.9 µm) recorded at the moderate spatial resolution of 1 km per pixel of MODIS satellites images. MIROVA currently monitors over 220 volcanoes, providing real-time post-processed products, such as lava effusion rates, in support to eruptive crisis management [20]. Figures 8-11 show the heat flux in Watt calculated by MIROVA system (on the left y scale, with blue stem, from 10 5 W to 10 10 W), and the number of hot pixels S2Pix detected by the new algorithm (on the right y scale, with red dots, from 1 to 10,000) on the eight volcanic case studies.…”

“…The MIR method [70] applied by MIROVA to MODIS images detects the thermal flow radiated from the surfaces with T > 500 K solely and return the VRP with a standard error of 30%. VRP values represent just the thermal output of high-temperature features, produced by the arrival of magma at the surface or at very shallow levels [20]). The comparison with MIROVA data is therefore relevant for the S2 algorithm proposed here, because both aim to detect the hottest portion, directly related to the ascent of magmatic fluids subaerially exposed.…”

“…Nowadays, thermal signals from volcanoes can be investigated by using new sensors and processing algorithms, and such advancements will continue to make thermal remote sensing an expanding field, whose techniques represent a safe and low-cost tool for improving volcano comprehension [18]. Fundamental parameters, such as the location, size and temperature of the hot target(s), the radiant flux and the time-averaged lava discharge rates (TADR) can be estimated from IR remote sensing and delivered to research centers, observatories and protection agencies that are in charge of volcano monitoring [19,20].…”

“…Several algorithms have been developed to automatically detect the presence of thermal anomalies based on MODIS data, each one with its own advantages and drawbacks, mainly related to variabilities in spatial-temporal-spectral resolution and temperature saturation limits (see [29]). Among all, MODVOLC [22] and MIROVA [25] are probably the most used in real-time volcanic monitoring [20].…”