S. Yu. Grishin
Izvestiya, Atmospheric and Oceanic Physics 2025; 61(9): 1129–1136
During the strong eruption of the Shiveluch volcano in April 2023, the active dome collapsed, the pyroclastic flows were released, and large-scale ashfall occurred. Satellite images from the Sentinel-2 satellite have determined the extent of area buried by high-temperature deposits (~60 km2) and assessed the diversity of buried and lost ecosystems. Pyroclastic deposits from the collapse overlaid the southeastern sector of the volcano over an area of more than 50 km2 at an altitude of ~2000–500 m above sea level. Below this area, the riverbeds and valleys up to a height of ~150 m were filled with narrow tongues of pyroclastic flows. The deposits of the tongues occupied an area of 12 km2; the lower boundary of one of them is located 22 km from the eruption center. Forest and dwarf alder vegetation was destroyed over an area of approximately 24 km2, primarily buried (up to 85% of the area), and also died due to trees being overwhelmed by pyroclastic flow plumes and due to the impact of pyroclastic surges. In the pyroclastic flow impact zone, the destroyed forests are formed primarily of birch Betula ermanii and larch Larix cajanderi, as well as thickets of dwarf alder Alnus fruticosa. An ash layer over 1 cm thick covered an area of over 10 000 km2 in central Kamchatka. In the forest belt on the slopes of Shiveluch, ash 6–10 cm in thickness was deposited; woody plants largely survived. Posteruptive phenomena in the form of secondary ash transport and the redeposition of pyroclastic material washed away by watercourses will continue for many years and will lead to the formation of new zones of damage and vegetation loss.
