Volcanic activity in Alaska and the Northern Mariana Islands in 2024—Summary of events and response of the Alaska Volcano Observatory

In 2024, the Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, increased seismicity, and other significant activity at 10 volcanic centers in Alaska and the Northern Mariana Islands. Eruptive activity in Alaska consisted of the eruption of a thick lava flow within the summit crater at Great Sitkin Volcano throughout the entire year and a small explosion at Atka volcano in March. Uplift, elevated seismicity, and the redevelopment of a summit meltwater lake was detected at Mount Spurr. A brief seismic swarm occurred at Mount Gareloi, while at Trident Volcano, Shishaldin Volcano, and Kanaga Volcano, seismicity declined to background levels, marking the end of unrest and volcanic activity for those volcanoes. Other activity that the Alaska Volcano Observatory responded to in 2024 included ash resuspension events at Mount Katmai, and a period of unrest at Mount Cleveland. Finally, at Ahyi seamount, in the Commonwealth of the Northern Marianas Islands, a plume of discolored ocean water observed in satellite data indicated underwater eruptive activity there.