Table compiled using data provided by the Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System. Number of monthly MODVOLC thermal alert pixels recorded at Erebus from 1 January 2017 to 31 December. Infrared satellite imagery from Sentinel-2 identified one or two lava lakes during January-March and September-December 2019 a few of the images showed gas emissions, possibly from melted snow (figure 28). A compilation of thermal alert pixels during 2017-2019 (table 5, continuing the table in BGVN 44:01) shows a wide range of detected activity in 2019, with a high of 162 in April. Courtesy of NASA Earth Observatory: image by Joshua Stevens, using data from NASA/METI/AIST/Japan Space Systems and U.S./Japan ASTER Science Team description by Kathryn Hansen.Īvailable since 2000, MODIS-MODVOLC data have shown a strong and nearly continuous thermal signal through 2019. Nearby areas that appear smooth are the snow- and ice-topped waters of McMurdo Sound. The blue patches are areas clear of surface snow, exposing glacial ice. The area was just days away from constant 24-hour sunlight when this image was acquired, with the Sun angle low enough to cast a long shadow towards the west. The false-color combines visible and near-infrared wavelengths of light (ASTER bands 3, 2, 1). Satellite image of Erebus (on left) acquired on 19 October 2019 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite.
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