The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Thursday, these notices are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of eruptions during the week, but rather a summary of activity that meet selected criteria. Carefully reviewed, detailed reports are published in the Bulletin of the Global Volcanism Network.

The Japan Meteorological Agency (JMA) reported eruptive activity at Me-Akan (also known as Meakan-dake, which means Meakan Peak) of the Akan volcanic complex on 8 March, though ashfall on snow surrounding Ponmachineshiri Crater?s 96-1 vent was observed in webcam images beforehand. Small-amplitude volcanic tremors were recorded by the seismic network on 27 February, 1 March, and 6 March; slight fluctuations in tilt were observed around the same times. Minor seismic amplitude fluctuations started on the evening of 6 March; the data was likely due to volcanic activity that may have occurred during 6 March through the morning of 8 March. At about 0915 on 8 March a very small eruption produced a grayish white ash plume that rose about 100 m above the Ponmachineshiri 96-1 Crater rim and drifted SE. Emissions continued until 1600, with gray ash plumes rising as high as 200 m above the crater rim. No significant changes to deeper volcanic activity were observed before or after the 8 March eruption. The Alert Level remained at 2 (the second lowest level on a 5-level scale) and the public was warned to exercise caution within 500 m of Ponmachineshiri Crater.

Source: Japan Meteorological Agency (JMA)

The eruption at Ambae continued during 4-11 March based on reports from the Vanuatu Meteorology and Geohazards Department (VMGD) and the Wellington Volcanic Ash Advisory Center (VAAC). On 10 March VMGD stated that seismicity began to decline on 7 March, though volcanic tremor remained high and volcano-seismic events continued to be recorded. The emissions visible in webcam images were mostly white, indicating less ash content, and they were rising to lower heights. Ground observations by an assessment and awareness team indicated that ashfall in villages to the W and S was gone or mostly gone, though ashfall still visible around the summit area. Very high amounts of sulfur dioxide emissions continued to be detected in satellite images along with low- to- moderate thermal anomalies. The VAAC reported that during 5-7 and 10-11 March ash plumes were visible in webcam and satellite images rising as high as 4.6 km (15,000 ft) a.s.l., or about 3 km above the summit, and drifting in multiple directions. According to news articles, residents in the S and SW parts of the island had experienced frequent ashfall and acid rain since the eruption intensified on 19 February. Ash fell in the Lolobanga and Vinarara communities by 25 February and acid rain affected areas from Loone (5 km NW) to Saranamundu. Ashfall contaminated water sources in Nduindui. About 50 residents, mainly from Lolobinanungwa village, had self-evacuated to Nduindui port by 5 March. A news article from 8 March noted that acid rain from the eruption affected water and food supplies in Port Vila, 310 km NW, and had reached Santo, Malakula (over 50 km SW), Pentecost (over 21 km E), and Ambrym (over 50 km S) islands. Residents of East Ambae described the eruption as very loud and that it could also be heard in E Santo, Pentecost, and Ambrym islands. The Alert Level remained at 3 (on a scale of 0-5), and the public was warned to stay outside of Danger Zone B, defined as a 3-km radius around the active vents in Lake Voui, and to stay away from drainages during heavy rains.

Sources: Penama Provincial Updates,Radio New Zealand ,Vanuatu Meteorology and Geohazards Department (VMGD),Wellington Volcanic Ash Advisory Center (VAAC)

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported periodic ash plumes at Lewotobi Laki-laki during 5-11 March. An eruptive event was recorded at 0456 on 5 March but not visually observed due to darkness and weather clouds. That same day, at 0523, at 1214, and at 1645, dense gray ash plumes rose 800-1,200 m above the summit and drifted N, NE, and E. At 0937 on 8 March a dense gray ash plume rose 1 km above the summit and drifted N and NE. No emissions were visible during 6-7 March, and white plumes rose 100-200 m above the summit and drifted N and NE during 8-9 March. A gray ash plume rose around 500 m above the summit and drifted E at 0130 on 11 March. At 0917 on that same day a gray ash plume rose around 800 m above the summit and drifted NE and E. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the exclusion zone was a radius of 4 km from the center of Laki-laki.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

The Observatoire Volcanologique du Piton de la Fournaise (OVPF) reported that the eruption at Piton de la Fournaise continued during 4-11 March. Deformation data indicated that inflation had resumed and persisted during the week. Low-amplitude tremor was at stable levels, with a few peaks likely indicating variations in degassing or morphological changes at the cone; overall, since the beginning of the eruption on 13 February, the amplitude has progressively increased. Lava flow rates estimated from satellite data were 1-10 cubic meters per second, though estimates could vary due to cloud cover. The crater opening at the active cone on the lower SE flank of Dolomieu Crater continued to close and lava was occasionally ejected above the crater rim. Lava mainly flowed downslope though tubes and reemerged as ?a?a and pahoehoe at elevations higher than the Grandes Pentes area, causing the flow field to widen and thicken. The main lava flow had stopped on 16 February, at about 1,725 m elevation or about 2.6 km from the road. The new flow that had begun descending the E flank on 3 March, S of the main branch, continued to advance. The flow descended from 1,175 m elevation on 7 March to 350 m elevation by the morning of 11 March; the flow rate increased to 35 m per hour during 10-11 March, higher than previous measurements of 19 m per hour. By 11 March the lava flow was 1.1 km from the National Route 2 road. The Alert Level remained at 2.1 (on a 0?4 scale).

Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported increased seismicity at Tambora. The seismic network recorded 267 deep volcanic earthquakes (VA) during January and a significantly higher total, 453 VA events, in February. The seismicity indicated that magma was moving from a deep reservoir to a location closer to the surface under the volcano. Seismicity remained at high levels during 1-9 March and was characterized by nine earthquakes indicating rockfalls, 88 deep volcanic earthquakes, and 40 local tectonic earthquakes. No emissions were visible, though weather conditions sometimes obscured views. The Alert Level was raised to 2 (the second lowest level on a four-level scale) at 1000 on 10 March and the public was advised to stay 3 km away from the center of the crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

The Servicio Nacional de Geología y Minería (SERNAGEOMIN) and the Sistema y Servicio Nacional de Prevención y Repuesta Ante Desastres (SENAPRED) reported that temperatures inside Villarrica?s summit crater increased during the second half of February based on satellite data. During an overflight of the crater on 6 March observers noted that a small area of lava was visible within a vent on the crater floor, deep within the summit crater. Lava hadn?t been seen at the surface since February 2025. The Volcanic Alert Level remained at Green (the lowest level on a four-level scale).

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN),Sistema y Servicio Nacional de Prevención y Repuesta Ante Desastres (SENAPRED)

The GeoNet reported minor ash in the emissions from Whakaari/White Island on 10 March. The size and coloration (brown to gray) of low-level steam-and-gas plumes during the previous week varied with atmospheric conditions, as seen in the Whakatane and Te Kaha webcams along the Bay of Plenty coast. An overflight confirmed that the emissions were rising from the active vent; there were no signs of erupted tephra on the crater floor. Minor amounts of sulfur dioxide emissions were identified in satellite data and were sometimes above background levels. On 10 March a pilot observed minor ash being emitted from the main vent, and photos shared with GeoNet showed minor ashfall on the crater floor. These observations indicated a slight increase in activity and a minor non-explosive eruption. The Volcanic Alert Level was raised to 3 (on a scale of 0-5) and the Aviation Color Code was raised to Orange (the second lowest level on a four-color scale). According to the Wellington Volcanic Ash Advisory Center (VAAC) a local aeronautic club also reported ash deposits on aircraft on 11 March. A low-level gas-and-steam plume with minor ash content rose 900 m (3,000 ft) a.s.l. based on webcam images and a pilot report.

Sources: GeoNet ,Wellington Volcanic Ash Advisory Center (VAAC)

The Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera?s Sakurajima volcano) during 2-9 March. Very small eruptive events were recorded and crater incandescence was visible in webcam images at night. Sulfur dioxide emissions were slightly high, averaging 1,300 tons per day on 3 March. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to be cautious within 2 km of both the Minimadake and Showa craters.

Source: Japan Meteorological Agency (JMA)

The Alaska Volcano Observatory (AVO) reported that slow lava effusion continued to feed a thick flow in Great Sitkin?s summit crater during 4-11 March. Seismic activity was very low and characterized by occasional small volcanic earthquakes and daily small rockfalls within the crater. Minor steaming and slow southward growth of the lava dome were observed in satellite views during 8-9 March. Weather clouds obscured satellite and webcam views during most of the week. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

Source: US Geological Survey Alaska Volcano Observatory (AVO)

The Tonga Geological Services reported continuing activity at Home Reef during 28 February-7 March. The main vent was about 25 m in diameter and located in the same central area as in 2025. Photos captured on 1 March by people onboard an Australian Navy vessel showed diffuse gray gas-and-ash puffs rising above the crater; the plumes were darker near the vent and whiter near the top. The ash plumes were not detected by satellite volcanic cloud monitoring data. The Aviation Color Code remained at Orange (the second highest level on a four-level scale, the Maritime Alert Level remained at Red (the highest level on a four-level scale) with advice to stay at least 2 nautical miles (3.7 km) from the island, and the Alert Level for residents of Vava?u and Ha?apai remained at Green (the first level on a four-level scale).

Source: Tonga Geological Services, Government of Tonga

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) reported that activity at Ibu continued during 5-11 March, with daily eruptive events recorded by the seismic network. Gray and white-and-gray ash plumes rose 200-600 m above the summit and drifted E, SE, S, and SW on most days; emissions were not visible during 10-11 March due to weather conditions. Incandescence at the summit was visible in a few nighttime webcam images. The Alert Level remained at 2 (the second lowest level on a four-level scale) and the public was advised to stay 2 km away from the active crater and 3.5 km away from the N crater wall opening.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilauea?s Kaluapele summit caldera, characterized by episodic fountaining, incandescence, and intermittent spatter from craters along the SW margin of Halema?uma?u Crater, continued at variable levels during 4-11 March. Both the N and S vents emitted continuous steam-and-gas plumes and incandescence at both vents was variable throughout the week. Spattering at the N vent was visible during the morning of 7 March and at both vents during 7-8 March. Continuous and strong incandescence from both vents was visible overnight during 9-10 March along with intermittent spattering and flaming. Activity at the N vent escalated at around 0817 on 10 March. Dome fountains rose 5-10 m high and produced a narrow lava flow that traveled about one-third of the way across the floor of Halema?uma?u Crater. Fountaining at the N vent began at 0917 and at the S vent just before 1000; fountains at both exceeded 300 m by 1050. Within an hour and a half fallout as large as a ~28 cm in diameter was reported at overlooks in Hawai?i Volcanoes National Park, creating hazardous ground conditions downwind, including neighboring communities and on Highway 11. An eruption plume rose as high as 7.6 km (25,000 ft) a.s.l. prompting HVO raised the Volcano Alert Level to Warning (the highest level on a four-level scale) and the Aviation Color Code to Red (the highest color on a four-color scale) at 1054. Tephra up to 7.6 cm in diameter fell in Volcano Village (6 km ENE) and Mauna Loa Estates (8 km ENE), residents of Royal Hawaiian Estates (7 km ENE) reported tephra up to 1.3 cm in diameter as well as Pele's hair, and Pele's hair was reported as far as Hilo (40 km NE), Hawaiian Paradise Park (40 km ENE), and the Hamakua Coast just north of Hilo. Hawaii County Civil Defense Agency closed Highway 11 between the 24 and 40 mile markers (a distance of ~26 km) at 1110 due to dangerous conditions created by falling tephra. Hawai?i Volcanoes National Park closed access to the summit during 1120-1130 and evacuated most visitors. The eruption plume rose higher than 9.1 km (30,000 ft) a.s.l. by 1130 and drifted N and E. According to a news article several flights in and out of Hilo airport were cancelled and a few others were diverted. The fountains had peaked at over 400 m high by 1100, though by midday the S vent fountain was rising 350-400 m and the N vent fountain was around 300 m tall. Lava flows covered about one third of the crater floor. By 1400 the S vent fountain had dropped to 300 m high and the N vent fountain had dropped to 220 m; by 1700 they were 220 m and 180 m tall, respectively. At 1807 HVO lowered the Volcano Alert Level to Watch (the third level on a four-level scale) and the Aviation Color Code to Orange (the third color on a four-color scale), noting that the eruption plume was rising 3-4.6 km (10,000-15,000 ft) a.s.l. and drifting NE. Pele?s hair, fine ash, and occasional pumice clasts less 1.2 cm in diameter was falling in the national park and adjacent communities. After nine hours and four minutes of continuous lava fountaining, the eruption abruptly ended at 1821. The average effusion rate was 400 cubic meters per second; the highest peak was 800 cubic meters per second, occurring at around 1030. An estimated 12 million cubic meters of lava erupted and covered about 50 percent of the Halema?uma?u Crater floor. During 10-11 March lava flows on the crater floor were incandescent and continued to spread, covering another 5-10 percent of the floor along the SE margin; the flow had dimmed by the morning. Both vents were brightly incandescent overnight. At 1130 on 11 March the national park reopened Crater Rim Drive West from the park entrance to Kilauea Military Camp; other areas of the park were expected to reopen after staff clear tephra fall from the roadways and other areas. Highway 11 had also reopened.

Sources: Hawaii News Now ,US Geological Survey Hawaiian Volcano Observatory (HVO) ,US Hawaii Volcanoes National Park