Sulfur dioxide (SO2) is a common volcanic gas that is released from magma within Earth’s upper crust. While SO2 is commonly released from Alaska’s active volcanoes, including Korovin, a recent increase in satellite detections of SO2 emissions from Korovin may be a sign of volcanic unrest. In sufficient quantity, SO2 can be readily measured from space due to its low quantity in background air. This image shows SO2 emissions from Korovin that were detected by the TROPOMI satellite sensor on October 26, 2020. In this image, the warmer colors represent larger quantities of SO2 measured within a column of atmosphere. These SO2 column densities are reported in Dobson Units (DU) where 1 DU = 2.85 x 10^-2 g of SO2/m^2. AVO will continue to monitor satellite detections of SO2 from Korovin, in combination with other volcano monitoring techniques, to evaluate ongoing activity at Korovin volcano.
Date: Oct 26th, 2020
Photographer: Lopez, Taryn
Korovin unrest 2020/10
Based on recent satellite detections of significant sulfur dioxide emissions and an increase in seismicity to a level above background, AVO raised the Aviation Color Code and Alert Level at Korovin Volcano to YELLOW/ADVISORY on October 28, 2020. Discrete earthquakes have been detected over the past two weeks and sulfur dioxide degassing has been detected four times in satellite data on October 15, 20 and 26. Clear satellite views show no other signs of activity at this time. AVO will continue to monitor the volcano for signs of volcanic activity.
In November, the unrest subsided, seismic activity returned to background levels and satellite observations showed no signs of further unrest. On December 3, 2020, AVO lowered the Aviation Color Code and Volcano Alert Level to GREEN/NORMAL.
Image courtesy of the AVO/UAF-GI.
Please cite the photographer and the Alaska Volcano Observatory / University of Alaska Fairbanks, Geophysical Institute when using this image.