The Weekly Volcanic Activity Report: August 27–September 2, 2025
New activity/unrest was reported for 6 volcanoes from August 27 to September 2, 2025. During the same period, ongoing activity was reported for 23 volcanoes.
Magma accumulation under Svartsengi nears eruption threshold, Iceland
Around 6 to 7 million m3 (212 to 247 million ft3) of magma have accumulated beneath Svartsengi, Iceland since the eruption on July 16, 2025. At the current rate of accumulation, the estimated threshold of 12 million m3 (424 million ft3) could be reached in the latter half of September, increasing the likelihood of a new eruption.
Lava fountains reach 150 m (500 feet) as Kīlauea eruption episode 32 starts
Episode 32 of the Halemaʻumaʻu eruption at Kīlauea volcano, Hawaii, began at 16:35 UTC (06:35 HST) on September 2, 2025, producing lava fountains up to 150 m (500 feet) high. The eruption remains confined to the summit crater within Hawai‘i Volcanoes National Park.
Earthquake swarm with 90 events detected at Teide volcano, Tenerife, Canary Islands
A new seismic swarm with 90 tremors was recorded beneath Mount Teide on the island of Tenerife, Canary Islands, Spain, on August 30, 2025.
Explosive eruption at Santa Maria volcano, Guatemala
An explosive eruption occurred at Santa María volcano, Guatemala, at around 06:40 UTC on August 29, 2025, producing an ash plume that reached 4.2 km (14 000 feet) above sea level — approximately 500 m (1 640 feet) above the summit.
Shinmoedake eruption sends ash plume to 7 km above sea level, Japan
Shinmoedake volcano, part of the Kirishimayama complex in Japan, erupted on August 27, 2025, producing an ash plume rising to 7 km (23 000 feet) a.s.l., which drifted south at 19 km/h (12 mph).
The Weekly Volcanic Activity Report: August 20–26, 2025
New activity/unrest was reported for 6 volcanoes from August 20 to 26, 2025. During the same period, ongoing activity was reported for 18 volcanoes.
Significant temperature increase detected at Kawah II crater lake, Mount Kelimutu, Indonesia
A significant increase in water temperature and sulfur gas emissions was detected at Kawah II of Mount Kelimutu, East Nusa Tenggara, Indonesia, on August 26, 2025. The volcano is a well-known tourist destination due to its three color-shifting crater lakes. The last recorded eruption at this volcano took place in 1968 (VEI 1).
Alert level raised as unrest increases at Shishaldin volcano, Alaska
The Alaska Volcano Observatory (AVO) raised the Volcano Alert Level for Shishaldin volcano, Alaska, to Advisory and the Aviation Color Code to Yellow at 11:48 AKDT (19:48 UTC) on August 25, 2025, following increased seismicity, gas emissions, and vapor activity.
Effusive vents and explosive activity persist at Mount Etna’s Southeast Crater, Italy
Strombolian activity and lava flows continue at Etna’s Southeast Crater, with new vents opening on the southern flank. On August 25, the Aviation Color Code was briefly raised to Red following intensified eruptive activity.
