Infrared Cameras Keep an Eye on Active Volcanoes
CATANIA, Italy, Aug. 26, 2011 — An infrared camera is just the tool to survey the biggest and most impressive hot spots on earth: volcanoes.
In Italy, home to at least two of the world’s most active volcanoes, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) and its branch in the city of Catania (INGV-CT) oversee the notorious Mount Etna and Mount Stromboli volcanoes as well as the somewhat less smoldering Aeolian Islands.
INGV-CT is setting up permanent infrared camera monitoring at major volcanic sites in its region. Researchers have mounted cameras made by Flir Systems near the Etna and Stromboli craters. The instruments provide data that enables the scientists to define threshold values that can be used as a warning system for volcanic explosions.
Infrared imaging helps model volcanic activity in Italy. (Photo: Flir Systems)
The institute uses a handheld Flir Systems camera during monthly low-level flights over Vulcano, a tiny, volcanically active island to the north of Sicily. In addition, the institute’s surveyors soon will install more cameras on a permanent basis to continuously observe the fumarole fields inside craters on the island. Fumaroles are holes from which hot gases and vapors issue. The resulting data will be used to make histograms to compare various fumarole areas and to monitor internal changes as well as external, seasonal effects on the fumaroles.
“Infrared monitoring of volcanoes gives new insights into the complex mechanisms which control the volcanic system,” said Sonia Calvari, volcanology unit manager at INGV-CT. “They help to measure and map active lava flows, to detect new cracks and landslide scars, to monitor the crater’s inner morphology and temperature, and to gather the change patterns which usually precede eruptions.”
The institute has been consistently employing infrared systems since 2001. During the 2002-2003 eruption of the Stromboli volcano, Calvari and her team conducted daily monitoring with a helicopter-mounted infrared camera hovering above the crater and offshore, and from vantage points overlooking the flow fields.
The INGV-CT researchers also obtained excellent results during the Etna and Stromboli eruptions of 2002 and 2003: Thermal surveying detected the opening of fractures along the Sciara del Fuoco (the hillside from which lava and deposits roll to the sea) one hour before the outburst that caused severe destruction in one of Stromboli island’s two villages on Dec. 30, 2002. The survey team collected and analyzed a total of 100,000 infrared images. Together with visual observations and seismic, gas geochemistry and ground deformation data, the imagery allowed them to reconstruct a detailed chronology of the eruptive events.
“Our survey provided a powerful demonstration of the capabilities of portable, easy-to-use, handheld infrared cameras to track and register complex volcanic processes and look through the curtain of smoke and gases,” Calvari said.
For more information, visit: www.ct.ingv.it
- thermal imaging
- The process of producing a visible two-dimensional image of a scene that is dependent on differences in thermal or infrared radiation from the scene reaching the aperture of the imaging device.
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