Volcano Watch: Volcano monitoring from space: InSAR time series success in Alaska

Sentinel-1 SAR satellite data analyzed with the Alaska Satellite Facility’s Hyp3 was used to create a time series of change over Kruzof Island for August 2018 through April 15, 2023. Deformation rates increased closer to the northeast flanks of Mount Edgecumbe from this dataset, with inflation rates as high as 4 inches (10.4 cm) per year in the line-of-sight direction. Top right inset shows earthquakes located under Kruzof Island (locations by Alaska Earthquake Center, retrieved through USGS comcat) between 2010 and April 2023. Earthquakes that can be located by the regional network start in 2020 (marked in blue). The earthquakes shown in red are all part of the 2022 swarm of activity. (Ronni Grapenthin & Yitian Cheng/AVO/UAF-GI)

Aerial view of Mount Edgecumbe crater in . Mount Edgecumbe is a volcano in Southeast Alaska, near Sitka. (Max Kaufman/AVO/UAF-GI)

In a recent “Volcano Watch” article, we learned about a remote sensing technique known as InSAR. This method of using satellite radar signals to detect changes to the surface of the Earth has been very beneficial for the monitoring of active volcanoes, especially in remote locations where it is difficult to install ground-based geophysical sensors. One such place where InSAR recently proved instrumental in detecting deformation of a volcano previously considered inactive was in Southeast Alaska.