Riassunto 7 4. Ground campaign organization 4.1 Surface characteristics 4.1.1 Description of Mt E... more Riassunto 7 4. Ground campaign organization 4.1 Surface characteristics 4.1.1 Description of Mt Etna test site 4.1.2 Sites measured during the June and July 2003 field campaigns 4.
An effective characterization of gas flaring is hampered by the lack of systematic, complete and ... more An effective characterization of gas flaring is hampered by the lack of systematic, complete and reliable data on its magnitude and spatial distribution. In the last years, a few satellite methods have been developed to provide independent information on gas flaring activity at global, national and local scale. Among these, a MODIS-based method, aimed at the computation of gas flared volumes by an Italian plant, was proposed. In this work, a more general version of this approach, named RST-FLARE, has been developed to provide reliable information on flaring sites localization and gas emitted volumes over a long time period for the Niger Delta region, one of the top five gas flaring areas in the world. Achieved results showed a good level of accuracy, in terms of flaring sites localization (95% of spatial match) and volume estimates (mean bias between in 16% and 20%, at annual scale and 2–9% in the long period) when compared to independent data, provided both by other satellite techn...
In May 2016, three powerful paroxysmal events, mild Strombolian activity, and lava emissions took... more In May 2016, three powerful paroxysmal events, mild Strombolian activity, and lava emissions took place at the summit crater area of Mt. Etna (Sicily, Italy). During, and immediately after the eruption, part of the North-East crater (NEC) collapsed, while extensive subsidence affected the Voragine crater (VOR). Since the end of the May eruptions, a diffuse fumarolic activity occurred from a fracture system that cuts the entire summit area. Starting from 7 August, a small vent (of ~20–30 m in diameter) opened up within the VOR crater, emitting high-temperature gases and producing volcanic glow which was visible at night. We investigated those volcanic phenomena from space, exploiting the information provided by the satellite-based system developed at the Institute of Methodologies for Environmental Analysis (IMAA), which monitors Italian volcanoes in near-real time by means of the RSTVOLC (Robust Satellite Techniques–volcanoes) algorithm. Results, achieved integrating Advanced Very H...
In this work, we assessed the possible relation of ionospheric perturbations observed by Detectio... more In this work, we assessed the possible relation of ionospheric perturbations observed by Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER), Global Positioning System total electron content (GPS TEC), National Oceanic and Atmospheric Administration (NOAA)-derived outgoing longwave-Earth radiation (OLR), and atmospheric chemical potential (ACP) measurements, with volcanic and Saharan dust events identified by ground and satellite-based medium infrared/thermal infrared (MIR/TIR) observations. The results indicated that the Mt. Etna (Italy) volcanic activity of 2006 was probably responsible for the ionospheric perturbations revealed by DEMETER on 4 November and 6 December and by GPS TEC observations on 4 November and 12 December. This activity also affected the OLR (on 26 October; 6 and 23 November; and 2, 6, and 14 December) and ACP (on 31 October–1 November) analyses. Similarly, two massive Saharan dust episodes, detected by Robust Satellite Techniq...
The Multispectral Instrument (MSI) and the Operational Land Imager (OLI), respectively onboard Se... more The Multispectral Instrument (MSI) and the Operational Land Imager (OLI), respectively onboard Sentinel-2A/2B and Landsat 8 satellites, thanks to their features especially in terms of spatial/spectral resolution, represents two important instruments for investigating thermal volcanic activity from space. In this study, we used data from those sensors to test an original multichannel algorithm, which aims at mapping volcanic thermal anomalies at a global scale. The algorithm, named Normalized Hotspot Indices (NHI), combines two normalized indices, analyzing near infrared (NIR) and short wave infrared (SWIR) radiances, to identify hotspot pixels in daylight conditions. Results, achieved studying a number of active volcanoes located in different geographic areas and characterized by a different eruptive behavior, demonstrated the NHI capacity in mapping both subtle and more intense volcanic thermal anomalies despite some limitations (e.g., missed detections because of clouds/volcanic plumes). In addition, the study shows that the performance of NHI might be further increased using some additional spectral/spatial tests, in view of a possible usage of this algorithm within a known multi-temporal scheme of satellite data analysis. The low processing times and the straight forth exportability to data from other sensors make NHI, which is sensitive even to other high temperature sources, suited for mapping hot volcanic targets integrating information provided by current and well-established satellite-based volcanoes monitoring systems.
The Robust Satellite Techniques (RST) is a multitemporal approach of satellite data analysis prop... more The Robust Satellite Techniques (RST) is a multitemporal approach of satellite data analysis proposed to study different natural/environmental hazards, including high risk volcanic phenomena. In particular, both thermal features and ash emissions may be investigated by RST, by using two specific configurations of such an approach. These algorithms have been tested on different volcanic areas exploiting data provided by polar satellite sensors, such as the Advanced Very High Resolution Radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS), showing a high trade-off between reliability and sensitivity of detection. In this work, the RST exportability on data provided by the Spinning Enhanced Visible Infrared Imager (SEVIRI), onboard Meteosat Second Generation (MSG) satellites, is assessed, by studying some recent eruptive events of Etna (Italy) and Grimsvotn (Iceland) volcanoes. Outcomes of this work confirm that the RST-based algorithms may give an important contribution for mitigating volcanic hazards during major eruptions, especially in the framework of integrated and automated early warning systems.
ABSTRACT In the recent years there has been a continuous increase of natural disasters affecting ... more ABSTRACT In the recent years there has been a continuous increase of natural disasters affecting the world. Their catastrophic consequences generally have extreme impacts both from an economic and social point of view. The effects are the more severe the higher are the population density and concentration of industrial facilities and infrastructures in disaster-affected areas. Systems able to provide timely information about the affected areas may help in supporting decision makers to manage the crisis. In this context, satellite data may give a useful and effectively support. The devastating earthquake occurred on March 11, 2011 off the Japan coasts produced a huge tsunami which strongly affected the municipality of Miyagi, where more than two millions of inhabitants were used to live. In this paper, the Robust Satellite Techniques (RST) approach was used to detect areas affected by the flood due to such a tsunami. RST have been already applied with satisfactory results for the detection and monitoring of flooded area by using data acquired both from polar (NOAA-AVHRR and EOS-MODIS) and geostationary (MSG-SEVIRI) system. The potential of such data acquired in the visible and infrared regions of the electromagnetic spectrum has already been verified, allowing the development of an all-day detection and monitoring system of flooded areas. In particular, the potential of RST when implemented on optical data acquired by the Japan geostationary MT-SAT series satellites for rapid detection of flooded areas within Sendai district will be investigated in this study. MT-SAT, guaranteeing a temporal resolution of 30 minutes and a spatial resolution of up to 1km in the visible channel, together with the high sensitivity to detecting changes, offered by RST approach, should assure the capability for a prompt and effective detection, allowing for a near real time identification of the dynamics and the evolution of the disaster. Results and main achievements of this study will be presented in this paper. Finally, open scientific issues and future perspectives will be discussed.
ABSTRACT RSTASH is a specific algorithm, based on the general Robust Satellite Techniques (RST) a... more ABSTRACT RSTASH is a specific algorithm, based on the general Robust Satellite Techniques (RST) approach, developed to identify and track ash clouds using satellite infrared data. An updated and optimized version of this algorithm, which analyzes even signal measured in the visible spectral band, has recently been developed and implemented on geostationary satellites data, for a better discrimination of ash and weather clouds in daytime. This advanced configuration was firstly tested during the Eyjafjallajökull (Iceland) eruption of April 2010 (by using Spinning Enhanced Visible and Infrared Imager sensor aboard Meteosat Second Generation), showing further improvements in terms of false positives reduction in comparison with standard RSTASH technique. Another experimental configuration of this method, analyzing signal measured in the SEVIRI sulphur dioxide absorption band (at 8.6µm), was also successfully used to qualitatively characterize volcanic plumes emitted by the same volcano in May 2010 in terms of SO2 concentration. Results of these studies are presented and discussed here, together with main achievements obtained monitoring ash cloud emitted during Shinmoedake (Japan) explosive eruption of 26-27 January 2011, exploiting the high temporal resolution of MTSAT Japanese geostationary satellites. Moreover, for both test cases, plume height estimations, obtained by applying two different literature methods, are compared with indipendent both ground- and satellite-based observations. In this work, RSTASH performances in detecting, tracking and characterizing ash clouds are discussed, focusing on main open issues and future perspectives.
ABSTRACT Presented work addresses the possible relationship between tectonic stress, electro-chem... more ABSTRACT Presented work addresses the possible relationship between tectonic stress, electro-chemical and thermodynamic processes in the atmosphere and increasing infrared (IR) flux as part of a larger family of electromagnetic (EM) phenomena related to earthquake activity. Thermal infra-red (TIR) surveys performed by polar orbiting (NOAA/AVHRR, MODIS) and geosynchronous weather satellites (GOES, METEOSAT) seems to indicate the appearance (from days to weeks before the event) of "anomalous" space-time TIR transients associated with the place (epicentral area, linear structures and fault systems) and the time of occurrence of a number of major earthquakes with M>5 and focal depths no deeper than 50km. As Earth emitted in 8-14 microns range the TIR signal measured from satellite strongly vary depending on meteorological conditions and other factors (space-time changes in atmospheric transmittance, time/season, solar and satellite zenithal angles and etc) independent from seismic activity, a preliminary definition of "anomalous TIR signal" should be given. To provide reliable discrimination of thermal anomalous area from the natural events (seasonal changes, local morphology) new robust approach (RAT) has been recently proposed (and successfully applied in the field of the monitoring of the major environmental risks) that permits to give a statistically based definition of thermal info-red (TIR) anomaly and reduce of false events detection. New techniques also were specifically developed to assure the precise co-registration of all satellite scenes and permit accurate time-series analysis of satellite observations. As final results we present examples of most recent 2000/2004 worldwide strong earthquakes and the techniques used to capture the tracks of thermal emission mid-IR anomalies and methodology for practical future use of such phenomena in the early warning systems.
ABSTRACT Many studies have been suggesting for decades a relation between Thermal Infrared (TIR) ... more ABSTRACT Many studies have been suggesting for decades a relation between Thermal Infrared (TIR) anomalies, observed from satellite, and seismic activity. In particular, the Robust Satellite Technique (RST) for the first time provided a statistics-based definition of "TIR anomalies" and a suitable method for their identification even in very different local (e.g. related to atmosphere and/or surface) and observational (e.g. related to time/season, but also to solar and satellite zenithal angles) conditions. The application of the RST approach to tens of earthquakes all around the world allowed us not to exclude, as already suggested by previous studies, that the TIR anomaly appearance in seismically active areas may be a consequence of the increase of green-house gas (such as CO2, CH4, etc.) emission rates. However, the application of the RST to seismic events which occurred in areas characterized by different prevailing degassing activities (i.e. CO2 or CH4) seems to highlight that, depending on the greenhouse gas which could be "responsible" for TIR anomalies, the shape of such anomalies appear to be more linear or more diffuse. In fact, it may be expected a more linear shape (i.e. an anomaly which seems to follow tectonic lineaments) in the case of greenhouse gases like CO2 which are heavier than the air so that they tend to gather within low morphological settings often formed along faults. On the other hand, when the diffusing gases are lighter than the air (e.g. CH4) it is expected that the overlapping of TIR anomalies on tectonic lineaments is less marked or even the anomaly seems to be quite scattered. The observation of such different shapes of TIR anomalies led us to further investigate the phenomenon origin. To this aim, a test was performed over an area with huge and highly variable CH4 emissions. The selected region was Azerbaijan, characterized by a large number of mud volcanoes which typically have methane as the principal component of their emissions. Following RST procedure, Meteosat-TIR images, acquired on the Caucasian area during mud volcano activities, were analysed. The space-time signature of the observed TIR anomalies seems to confirm, even by comparison with the ones observed in presence of degassing activity dominated by CO2 (heavier than air), that their behaviour actually depends on the density (greater or lower than the air) of the main emitted green-house gases.
2007 International Workshop on the Analysis of Multi-temporal Remote Sensing Images, 2007
... 6 Cloud-detection has been wherever performed by using the One-channel Cloud-detectionApproac... more ... 6 Cloud-detection has been wherever performed by using the One-channel Cloud-detectionApproach (OCA) described in Ref. [23]. Page 4. It April 2003 2ndApril 2003 3th April 2003 ... increase precursor of Gonghe earthquake of magnitude 7.0, Qinghai ...
ABSTRACT Several studies performed in the past 30 years suggested the existence of anomalous spac... more ABSTRACT Several studies performed in the past 30 years suggested the existence of anomalous space-time transients, in the thermal infrared (TIR) radiation emitted by the Earth, possibly related to earthquake preparatory phenomena. Among various theories about their origin, the abrupt increase in greenhouse gas (such as CO2, CH4, etc.) emission rates was also proposed to explain the appearance of anomalous TIR signal transients in some relation with the place and the time of earthquake occurrence. As, under stable atmospheric conditions, the accumulation/dispersion of gases in the air depends on their molecular weight, CO2 tends to collect near the ground and layer forming “rivers” and/or “lakes” following terrain morphology close to its sources. On the contrary, the dispersion pattern of CH4, whose mass is smaller than that of CO2, is less affected by the terrain morphology so that the gas tends to be dispersed very readily, basically governed by the wind and normal atmospheric turbulence. If TIR anomalies are effectively related to exceptional degassing events, such differences should produce very different spatial/temporal patterns in the TIR anomalies observed, depending on the greenhouse gas emanated. In this paper, this hypothesis has been tested from different viewpoints and the results show that:a)an increase of only 2–3 times the normal CO2 mixing ratio level is sufficient to justify the excesses observed in TIR signal.b)areas dominated by diffusing gases which are heavier than the air (like CO2) show (as expected) anomalous TIR patterns which follow morphological lineaments (e.g. tectonic faults); in areas dominated by diffusing gases which are lighter than the air (like CH4) the TIR patterns observed spread over wide zones, following prevailing winds and diffusing around with less marked correlation with morphological lineaments.c)anomalous TIR patterns were observed over the Azerbaijan region during the Bozdag–Guzdak mud volcano eruption (May 1995), showing exactly the same spatial/temporal behavior expected for methane-dominated degassing areas.
2008 Second Workshop on Use of Remote Sensing Techniques for Monitoring Volcanoes and Seismogenic Areas, 2008
Based on Thermal Infrared (TIR) satellite observations, previous studies have been suggesting for... more Based on Thermal Infrared (TIR) satellite observations, previous studies have been suggesting for decades a relation between TIR anomalies and seismic activity. Among the others, a Robust Satellite data analysis Technique (RST) was proposed which provides a statistically based definition of ?TIR anomalies? and a suitable method for their identification even in very different local (e.g. related to atmosphere and/or
In the last few years, Robust Satellite data analysis Techniques (RST) have been proposed and suc... more In the last few years, Robust Satellite data analysis Techniques (RST) have been proposed and successfully applied for monitoring major natural and environmental risks. Among the various fields of application, RST analysis has been used as a suitable tool for satellite TIR surveys in seismically active regions, devoted to detect and monitor thermal anomalies possibly related to earthquake occurrence. In this work, RST has been applied, for the first time, to thermal infrared observations collected by MODIS (Moderate Resolution Imaging Spectroradiometer) -the sensor onboard EOS (Earth Observing System) satellites -in the case of Abruzzo (Italy) earthquake occurred on 6 April 2009 (M L ∼5.8). First achievements, shown in this work, seem to confirm the sensitivity of the proposed approach in detecting perturbations of the Earths emission thermal field few days before the event. The reliability of such results, based on the analysis of 10 years of MODIS observations, seems to be supported by the results achieved analyzing the same area in similar observation conditions but in seismically unperturbed periods (no earthquakes with M L ≥5) that will be also presented.
Several authors claim a space-time correlation between increases in Earth's emitted Thermal Infra... more Several authors claim a space-time correlation between increases in Earth's emitted Thermal Infra-Red (TIR) radiation and earthquake occurrence. The main problems of such studies regard data analysis and interpretation, which are often done without a validation/confutation control. In this context, a robust data analysis technique (RST, i.e. Robust Satellite Techniques) is proposed which permits a statistically based definition of TIR «anomaly» and uses a validation/confutation approach. This technique was already applied to satellite TIR surveys in seismic regions for about twenty earthquakes that occurred in the world. In this work RST is applied for the first time to a time sequence of seismic events. Nine years of Meteosat TIR observations have been analyzed to characterize the unperturbed TIR signal behaviour at specific observation times and locations. The main seismic events of the October 1997 Umbria-Marche sequence have been considered for validation, and relatively unperturbed periods (no earthquakes with Mb ≥ 4) were taken for confutation purposes. Positive time-space persistent TIR anomalies were observed during seismic periods, generally overlapping the principal tectonic lineaments of the region and sometimes focusing on the vicinity of the epicentre. No similar (in terms of relative intensity and space-time persistence) TIR anomalies were detected during seismically unperturbed periods.
Space-time fluctuations of Earth's emitted Thermal Infrared (TIR) radiation have been observed fr... more Space-time fluctuations of Earth's emitted Thermal Infrared (TIR) radiation have been observed from satellite months to weeks before earthquakes occurrence.
A robust satellite data analysis technique (RAT) has been recently proposed as a suitable tool fo... more A robust satellite data analysis technique (RAT) has been recently proposed as a suitable tool for satellite TIR surveys in seismically active regions and already successfully tested in different cases of earthquakes (both high and medium-low magnitudes).
Remote Sensing for Environmental Monitoring, GIS Applications, and Geology, 2002
ABSTRACT In this work, a simple and robust technique, that allows for automatic identifying of su... more ABSTRACT In this work, a simple and robust technique, that allows for automatic identifying of surface materials by using Multispectral Infrared and Visible Imaging Spectrometer (MIVIS) radiances was applied in order to recognize rocky outcrops in the area of the Pollino National Park (southern Apennines, Italy). Tests were made over an area which is topographically complex and geologically characterized by ophiolite-bearing units (Ligurian units), Meso-Cenozoic shallow-water carbonates (Pollino Unit) and Plio-Quaternary sediments. Among ophiolitic rocks, serpentinite was chosen as a test-rock as it is present in isolated outcrops in the test-area, besides subtending important environmental problems because it contains asbestos. Geological information, coming from field observations or geological maps, was used as input and in order to verify the results of the MIVIS data processing.
Riassunto 7 4. Ground campaign organization 4.1 Surface characteristics 4.1.1 Description of Mt E... more Riassunto 7 4. Ground campaign organization 4.1 Surface characteristics 4.1.1 Description of Mt Etna test site 4.1.2 Sites measured during the June and July 2003 field campaigns 4.
An effective characterization of gas flaring is hampered by the lack of systematic, complete and ... more An effective characterization of gas flaring is hampered by the lack of systematic, complete and reliable data on its magnitude and spatial distribution. In the last years, a few satellite methods have been developed to provide independent information on gas flaring activity at global, national and local scale. Among these, a MODIS-based method, aimed at the computation of gas flared volumes by an Italian plant, was proposed. In this work, a more general version of this approach, named RST-FLARE, has been developed to provide reliable information on flaring sites localization and gas emitted volumes over a long time period for the Niger Delta region, one of the top five gas flaring areas in the world. Achieved results showed a good level of accuracy, in terms of flaring sites localization (95% of spatial match) and volume estimates (mean bias between in 16% and 20%, at annual scale and 2–9% in the long period) when compared to independent data, provided both by other satellite techn...
In May 2016, three powerful paroxysmal events, mild Strombolian activity, and lava emissions took... more In May 2016, three powerful paroxysmal events, mild Strombolian activity, and lava emissions took place at the summit crater area of Mt. Etna (Sicily, Italy). During, and immediately after the eruption, part of the North-East crater (NEC) collapsed, while extensive subsidence affected the Voragine crater (VOR). Since the end of the May eruptions, a diffuse fumarolic activity occurred from a fracture system that cuts the entire summit area. Starting from 7 August, a small vent (of ~20–30 m in diameter) opened up within the VOR crater, emitting high-temperature gases and producing volcanic glow which was visible at night. We investigated those volcanic phenomena from space, exploiting the information provided by the satellite-based system developed at the Institute of Methodologies for Environmental Analysis (IMAA), which monitors Italian volcanoes in near-real time by means of the RSTVOLC (Robust Satellite Techniques–volcanoes) algorithm. Results, achieved integrating Advanced Very H...
In this work, we assessed the possible relation of ionospheric perturbations observed by Detectio... more In this work, we assessed the possible relation of ionospheric perturbations observed by Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER), Global Positioning System total electron content (GPS TEC), National Oceanic and Atmospheric Administration (NOAA)-derived outgoing longwave-Earth radiation (OLR), and atmospheric chemical potential (ACP) measurements, with volcanic and Saharan dust events identified by ground and satellite-based medium infrared/thermal infrared (MIR/TIR) observations. The results indicated that the Mt. Etna (Italy) volcanic activity of 2006 was probably responsible for the ionospheric perturbations revealed by DEMETER on 4 November and 6 December and by GPS TEC observations on 4 November and 12 December. This activity also affected the OLR (on 26 October; 6 and 23 November; and 2, 6, and 14 December) and ACP (on 31 October–1 November) analyses. Similarly, two massive Saharan dust episodes, detected by Robust Satellite Techniq...
The Multispectral Instrument (MSI) and the Operational Land Imager (OLI), respectively onboard Se... more The Multispectral Instrument (MSI) and the Operational Land Imager (OLI), respectively onboard Sentinel-2A/2B and Landsat 8 satellites, thanks to their features especially in terms of spatial/spectral resolution, represents two important instruments for investigating thermal volcanic activity from space. In this study, we used data from those sensors to test an original multichannel algorithm, which aims at mapping volcanic thermal anomalies at a global scale. The algorithm, named Normalized Hotspot Indices (NHI), combines two normalized indices, analyzing near infrared (NIR) and short wave infrared (SWIR) radiances, to identify hotspot pixels in daylight conditions. Results, achieved studying a number of active volcanoes located in different geographic areas and characterized by a different eruptive behavior, demonstrated the NHI capacity in mapping both subtle and more intense volcanic thermal anomalies despite some limitations (e.g., missed detections because of clouds/volcanic plumes). In addition, the study shows that the performance of NHI might be further increased using some additional spectral/spatial tests, in view of a possible usage of this algorithm within a known multi-temporal scheme of satellite data analysis. The low processing times and the straight forth exportability to data from other sensors make NHI, which is sensitive even to other high temperature sources, suited for mapping hot volcanic targets integrating information provided by current and well-established satellite-based volcanoes monitoring systems.
The Robust Satellite Techniques (RST) is a multitemporal approach of satellite data analysis prop... more The Robust Satellite Techniques (RST) is a multitemporal approach of satellite data analysis proposed to study different natural/environmental hazards, including high risk volcanic phenomena. In particular, both thermal features and ash emissions may be investigated by RST, by using two specific configurations of such an approach. These algorithms have been tested on different volcanic areas exploiting data provided by polar satellite sensors, such as the Advanced Very High Resolution Radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS), showing a high trade-off between reliability and sensitivity of detection. In this work, the RST exportability on data provided by the Spinning Enhanced Visible Infrared Imager (SEVIRI), onboard Meteosat Second Generation (MSG) satellites, is assessed, by studying some recent eruptive events of Etna (Italy) and Grimsvotn (Iceland) volcanoes. Outcomes of this work confirm that the RST-based algorithms may give an important contribution for mitigating volcanic hazards during major eruptions, especially in the framework of integrated and automated early warning systems.
ABSTRACT In the recent years there has been a continuous increase of natural disasters affecting ... more ABSTRACT In the recent years there has been a continuous increase of natural disasters affecting the world. Their catastrophic consequences generally have extreme impacts both from an economic and social point of view. The effects are the more severe the higher are the population density and concentration of industrial facilities and infrastructures in disaster-affected areas. Systems able to provide timely information about the affected areas may help in supporting decision makers to manage the crisis. In this context, satellite data may give a useful and effectively support. The devastating earthquake occurred on March 11, 2011 off the Japan coasts produced a huge tsunami which strongly affected the municipality of Miyagi, where more than two millions of inhabitants were used to live. In this paper, the Robust Satellite Techniques (RST) approach was used to detect areas affected by the flood due to such a tsunami. RST have been already applied with satisfactory results for the detection and monitoring of flooded area by using data acquired both from polar (NOAA-AVHRR and EOS-MODIS) and geostationary (MSG-SEVIRI) system. The potential of such data acquired in the visible and infrared regions of the electromagnetic spectrum has already been verified, allowing the development of an all-day detection and monitoring system of flooded areas. In particular, the potential of RST when implemented on optical data acquired by the Japan geostationary MT-SAT series satellites for rapid detection of flooded areas within Sendai district will be investigated in this study. MT-SAT, guaranteeing a temporal resolution of 30 minutes and a spatial resolution of up to 1km in the visible channel, together with the high sensitivity to detecting changes, offered by RST approach, should assure the capability for a prompt and effective detection, allowing for a near real time identification of the dynamics and the evolution of the disaster. Results and main achievements of this study will be presented in this paper. Finally, open scientific issues and future perspectives will be discussed.
ABSTRACT RSTASH is a specific algorithm, based on the general Robust Satellite Techniques (RST) a... more ABSTRACT RSTASH is a specific algorithm, based on the general Robust Satellite Techniques (RST) approach, developed to identify and track ash clouds using satellite infrared data. An updated and optimized version of this algorithm, which analyzes even signal measured in the visible spectral band, has recently been developed and implemented on geostationary satellites data, for a better discrimination of ash and weather clouds in daytime. This advanced configuration was firstly tested during the Eyjafjallajökull (Iceland) eruption of April 2010 (by using Spinning Enhanced Visible and Infrared Imager sensor aboard Meteosat Second Generation), showing further improvements in terms of false positives reduction in comparison with standard RSTASH technique. Another experimental configuration of this method, analyzing signal measured in the SEVIRI sulphur dioxide absorption band (at 8.6µm), was also successfully used to qualitatively characterize volcanic plumes emitted by the same volcano in May 2010 in terms of SO2 concentration. Results of these studies are presented and discussed here, together with main achievements obtained monitoring ash cloud emitted during Shinmoedake (Japan) explosive eruption of 26-27 January 2011, exploiting the high temporal resolution of MTSAT Japanese geostationary satellites. Moreover, for both test cases, plume height estimations, obtained by applying two different literature methods, are compared with indipendent both ground- and satellite-based observations. In this work, RSTASH performances in detecting, tracking and characterizing ash clouds are discussed, focusing on main open issues and future perspectives.
ABSTRACT Presented work addresses the possible relationship between tectonic stress, electro-chem... more ABSTRACT Presented work addresses the possible relationship between tectonic stress, electro-chemical and thermodynamic processes in the atmosphere and increasing infrared (IR) flux as part of a larger family of electromagnetic (EM) phenomena related to earthquake activity. Thermal infra-red (TIR) surveys performed by polar orbiting (NOAA/AVHRR, MODIS) and geosynchronous weather satellites (GOES, METEOSAT) seems to indicate the appearance (from days to weeks before the event) of "anomalous" space-time TIR transients associated with the place (epicentral area, linear structures and fault systems) and the time of occurrence of a number of major earthquakes with M>5 and focal depths no deeper than 50km. As Earth emitted in 8-14 microns range the TIR signal measured from satellite strongly vary depending on meteorological conditions and other factors (space-time changes in atmospheric transmittance, time/season, solar and satellite zenithal angles and etc) independent from seismic activity, a preliminary definition of "anomalous TIR signal" should be given. To provide reliable discrimination of thermal anomalous area from the natural events (seasonal changes, local morphology) new robust approach (RAT) has been recently proposed (and successfully applied in the field of the monitoring of the major environmental risks) that permits to give a statistically based definition of thermal info-red (TIR) anomaly and reduce of false events detection. New techniques also were specifically developed to assure the precise co-registration of all satellite scenes and permit accurate time-series analysis of satellite observations. As final results we present examples of most recent 2000/2004 worldwide strong earthquakes and the techniques used to capture the tracks of thermal emission mid-IR anomalies and methodology for practical future use of such phenomena in the early warning systems.
ABSTRACT Many studies have been suggesting for decades a relation between Thermal Infrared (TIR) ... more ABSTRACT Many studies have been suggesting for decades a relation between Thermal Infrared (TIR) anomalies, observed from satellite, and seismic activity. In particular, the Robust Satellite Technique (RST) for the first time provided a statistics-based definition of "TIR anomalies" and a suitable method for their identification even in very different local (e.g. related to atmosphere and/or surface) and observational (e.g. related to time/season, but also to solar and satellite zenithal angles) conditions. The application of the RST approach to tens of earthquakes all around the world allowed us not to exclude, as already suggested by previous studies, that the TIR anomaly appearance in seismically active areas may be a consequence of the increase of green-house gas (such as CO2, CH4, etc.) emission rates. However, the application of the RST to seismic events which occurred in areas characterized by different prevailing degassing activities (i.e. CO2 or CH4) seems to highlight that, depending on the greenhouse gas which could be "responsible" for TIR anomalies, the shape of such anomalies appear to be more linear or more diffuse. In fact, it may be expected a more linear shape (i.e. an anomaly which seems to follow tectonic lineaments) in the case of greenhouse gases like CO2 which are heavier than the air so that they tend to gather within low morphological settings often formed along faults. On the other hand, when the diffusing gases are lighter than the air (e.g. CH4) it is expected that the overlapping of TIR anomalies on tectonic lineaments is less marked or even the anomaly seems to be quite scattered. The observation of such different shapes of TIR anomalies led us to further investigate the phenomenon origin. To this aim, a test was performed over an area with huge and highly variable CH4 emissions. The selected region was Azerbaijan, characterized by a large number of mud volcanoes which typically have methane as the principal component of their emissions. Following RST procedure, Meteosat-TIR images, acquired on the Caucasian area during mud volcano activities, were analysed. The space-time signature of the observed TIR anomalies seems to confirm, even by comparison with the ones observed in presence of degassing activity dominated by CO2 (heavier than air), that their behaviour actually depends on the density (greater or lower than the air) of the main emitted green-house gases.
2007 International Workshop on the Analysis of Multi-temporal Remote Sensing Images, 2007
... 6 Cloud-detection has been wherever performed by using the One-channel Cloud-detectionApproac... more ... 6 Cloud-detection has been wherever performed by using the One-channel Cloud-detectionApproach (OCA) described in Ref. [23]. Page 4. It April 2003 2ndApril 2003 3th April 2003 ... increase precursor of Gonghe earthquake of magnitude 7.0, Qinghai ...
ABSTRACT Several studies performed in the past 30 years suggested the existence of anomalous spac... more ABSTRACT Several studies performed in the past 30 years suggested the existence of anomalous space-time transients, in the thermal infrared (TIR) radiation emitted by the Earth, possibly related to earthquake preparatory phenomena. Among various theories about their origin, the abrupt increase in greenhouse gas (such as CO2, CH4, etc.) emission rates was also proposed to explain the appearance of anomalous TIR signal transients in some relation with the place and the time of earthquake occurrence. As, under stable atmospheric conditions, the accumulation/dispersion of gases in the air depends on their molecular weight, CO2 tends to collect near the ground and layer forming “rivers” and/or “lakes” following terrain morphology close to its sources. On the contrary, the dispersion pattern of CH4, whose mass is smaller than that of CO2, is less affected by the terrain morphology so that the gas tends to be dispersed very readily, basically governed by the wind and normal atmospheric turbulence. If TIR anomalies are effectively related to exceptional degassing events, such differences should produce very different spatial/temporal patterns in the TIR anomalies observed, depending on the greenhouse gas emanated. In this paper, this hypothesis has been tested from different viewpoints and the results show that:a)an increase of only 2–3 times the normal CO2 mixing ratio level is sufficient to justify the excesses observed in TIR signal.b)areas dominated by diffusing gases which are heavier than the air (like CO2) show (as expected) anomalous TIR patterns which follow morphological lineaments (e.g. tectonic faults); in areas dominated by diffusing gases which are lighter than the air (like CH4) the TIR patterns observed spread over wide zones, following prevailing winds and diffusing around with less marked correlation with morphological lineaments.c)anomalous TIR patterns were observed over the Azerbaijan region during the Bozdag–Guzdak mud volcano eruption (May 1995), showing exactly the same spatial/temporal behavior expected for methane-dominated degassing areas.
2008 Second Workshop on Use of Remote Sensing Techniques for Monitoring Volcanoes and Seismogenic Areas, 2008
Based on Thermal Infrared (TIR) satellite observations, previous studies have been suggesting for... more Based on Thermal Infrared (TIR) satellite observations, previous studies have been suggesting for decades a relation between TIR anomalies and seismic activity. Among the others, a Robust Satellite data analysis Technique (RST) was proposed which provides a statistically based definition of ?TIR anomalies? and a suitable method for their identification even in very different local (e.g. related to atmosphere and/or
In the last few years, Robust Satellite data analysis Techniques (RST) have been proposed and suc... more In the last few years, Robust Satellite data analysis Techniques (RST) have been proposed and successfully applied for monitoring major natural and environmental risks. Among the various fields of application, RST analysis has been used as a suitable tool for satellite TIR surveys in seismically active regions, devoted to detect and monitor thermal anomalies possibly related to earthquake occurrence. In this work, RST has been applied, for the first time, to thermal infrared observations collected by MODIS (Moderate Resolution Imaging Spectroradiometer) -the sensor onboard EOS (Earth Observing System) satellites -in the case of Abruzzo (Italy) earthquake occurred on 6 April 2009 (M L ∼5.8). First achievements, shown in this work, seem to confirm the sensitivity of the proposed approach in detecting perturbations of the Earths emission thermal field few days before the event. The reliability of such results, based on the analysis of 10 years of MODIS observations, seems to be supported by the results achieved analyzing the same area in similar observation conditions but in seismically unperturbed periods (no earthquakes with M L ≥5) that will be also presented.
Several authors claim a space-time correlation between increases in Earth's emitted Thermal Infra... more Several authors claim a space-time correlation between increases in Earth's emitted Thermal Infra-Red (TIR) radiation and earthquake occurrence. The main problems of such studies regard data analysis and interpretation, which are often done without a validation/confutation control. In this context, a robust data analysis technique (RST, i.e. Robust Satellite Techniques) is proposed which permits a statistically based definition of TIR «anomaly» and uses a validation/confutation approach. This technique was already applied to satellite TIR surveys in seismic regions for about twenty earthquakes that occurred in the world. In this work RST is applied for the first time to a time sequence of seismic events. Nine years of Meteosat TIR observations have been analyzed to characterize the unperturbed TIR signal behaviour at specific observation times and locations. The main seismic events of the October 1997 Umbria-Marche sequence have been considered for validation, and relatively unperturbed periods (no earthquakes with Mb ≥ 4) were taken for confutation purposes. Positive time-space persistent TIR anomalies were observed during seismic periods, generally overlapping the principal tectonic lineaments of the region and sometimes focusing on the vicinity of the epicentre. No similar (in terms of relative intensity and space-time persistence) TIR anomalies were detected during seismically unperturbed periods.
Space-time fluctuations of Earth's emitted Thermal Infrared (TIR) radiation have been observed fr... more Space-time fluctuations of Earth's emitted Thermal Infrared (TIR) radiation have been observed from satellite months to weeks before earthquakes occurrence.
A robust satellite data analysis technique (RAT) has been recently proposed as a suitable tool fo... more A robust satellite data analysis technique (RAT) has been recently proposed as a suitable tool for satellite TIR surveys in seismically active regions and already successfully tested in different cases of earthquakes (both high and medium-low magnitudes).
Remote Sensing for Environmental Monitoring, GIS Applications, and Geology, 2002
ABSTRACT In this work, a simple and robust technique, that allows for automatic identifying of su... more ABSTRACT In this work, a simple and robust technique, that allows for automatic identifying of surface materials by using Multispectral Infrared and Visible Imaging Spectrometer (MIVIS) radiances was applied in order to recognize rocky outcrops in the area of the Pollino National Park (southern Apennines, Italy). Tests were made over an area which is topographically complex and geologically characterized by ophiolite-bearing units (Ligurian units), Meso-Cenozoic shallow-water carbonates (Pollino Unit) and Plio-Quaternary sediments. Among ophiolitic rocks, serpentinite was chosen as a test-rock as it is present in isolated outcrops in the test-area, besides subtending important environmental problems because it contains asbestos. Geological information, coming from field observations or geological maps, was used as input and in order to verify the results of the MIVIS data processing.
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