An explosive eruption at Bagana on 7 July send a large ash, gas, and steam plume to high altitudes and caused significant ashfall in local communities. A report issued by the Autonomous Bougainville Government (Torokina District, Education Section) on 10 July noted that significant ash began falling during 2000-2100 on 7 July and covered most areas in the Vuakovi, Gotana (9 km SW), Koromaketo, Laruma and Atsilima villages. By about 2200 on 7 July the eruption plume had reached upper tropospheric altitudes based on satellite images. Sulfur dioxide detections in satellite images from 8 July indicated that the plume, likely a mixture of gases, ice, and ash, had risen to 16-18 km (52,500-59,100 ft) a.s.l., reaching the tropopause. Ashfall reportedly continued until 9 July. The ashfall covered vegetation, destroying bushes and gardens, and contaminated rivers and streams used for washing and drinking water; residents drank from coconuts and used fresh ground water accessible through bamboo pipes.

Sources: Andrew Tupper, Natural Hazards Consulting, Simon Carn, Rabaul Volcano Observatory (RVO), Autonomous Bougainville Government

Icelandic Meteorological Office (IMO) reported that at 2330 on 6 July earthquake activity increased in an area close to Eldey and by 1500 on 7 July the seismic network had detected over 480 events. The earthquakes were located at depths of around 8 km, with several of the events over M 3 and six over M 4; the largest event was a M 4.5 recorded at 0506 on 7 July. Activity that strong had not previously been detected in conjunction with seismic swarms related to magma intrusions in Fagradalsfjall. The Aviation Color Code was raised to Yellow (the second level on a four-color scale). On 11 July IMO noted that seismicity had decreased during the past few days so at 1640 the Aviation Color Code was lowered to Green.

Source: Icelandic Meteorological Office (IMO)

Icelandic Meteorological Office (IMO) reported that a new fissure eruption in the Fagradalsfjall volcanic system began on 10 July after intensifying seismicity over the previous month and inflation that was first noted in April. At 1055 on 5 July IMO raised the Aviation Color Code to Orange (the third level on a four-color scale). By 1330 on 7 July there had been more than 7,000 earthquakes detected in the swarm that began on 3 July. Epicenters were aligned NE-SW between Fagradalsfjall and the Keilir cone, NNE from the 2021 and 2022 eruptions, and mostly concentrated just N of the Litli Hrútur hill. Deformation data (GPS and radar interferometry) showed uplift in the same area, suggesting a magmatic dike intrusion that reached to 1 km depth by early on 6 July. Seismicity decreased during 6-7 July and the rate of deformation slowed, with analysis showing that by 9-10 July the dike had propagated 1 km further NE.

Tremor was detected at 1425 on 10 July and continued to intensify, leading to an eruption at 1640 just NW of Litli-Hrútur. Webcam images showed visible gas emissions and incandescence, but no major ash emissions. IMO raised the Aviation Color Code to Red (the highest level on a four-color scale) at 1707. Flowing lava from a NE-SW fissure that was about 200 m long was confirmed by people present in the area and webcam images; at 1724 the Aviation Color Code was lowered back to Orange. The fissure was mainly located in a depression and bisected the E and NE flanks of Litli Hrútur. Based on observations from drone video the fissure quickly reached about 900 m long according to estimates from Institute of Earth Sciences. Lava fountaining occurred along the fissure, sending lava flows S. Gas-and-steam emissions drifted NW. According to Almannavarnadeild ríkislögreglustjóra, the police closed the area around the eruption to tourists due to the high concentrations of volcanic gases and particulates from burning vegetation.

Tremor levels peaked between 2100 on 10 July and 0000 on 11 July, then steadily declined through 1100. By 1250 on 11 July the intensity of the eruption had noticeably decreased, with fewer active lava fountains. Only one vent with an elongated crater and multiple lava fountains was active by 1635. Gas plumes rose as high as 4 km above the vent. Lava flows mostly traveled SE and flowed into a shallow valley S of Litli-Hrútur. IMO noted that if lava continued to flow S it may come into contact with the 2022 Merardalir lava flow. A 10-km-long trail from the road up to the eruption site was opened to the public.

Sources: Icelandic Meteorological Office (IMO), Almannavarnadeild ríkislögreglustjóra (National Commissioner of the Icelandic Police and Department of Civil Protection and Emergency Management), Institute of Earth Sciences

JMA reported that global navigation satellite system (GNSS) data indicated minor inflation beginning in May at shallow depths beneath Ioyama, located on the NW flank of the Karakuni-dake stratovolcano in the Kirishimayama volcano group. Volcanic tremor was recorded at 1650 on 7 July for the first time since 19 June 2018. JMA raised the Alert Level to 2 (on a 5-level scale) at 1715 on 7 July and warned the public to stay 1 km away from Ioyama. A few shallow volcanic earthquakes were recorded during 7-10 July. Weather conditions mostly prevented visual observations of the fumarolic areas near the crater.

Source: Japan Meteorological Agency (JMA)

KVERT reported that the minor Strombolian eruption at Klyuchevskoy continued during 29 June-6 July. A daily thermal anomaly was identified in satellite images. Small ash plumes were occasionally observed over the crater during 4-6 July. The Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

JMA reported that shallow volcanic earthquakes at Kuchinoerabujima had been occurring frequently starting in late June with most epicenters located near Furudake Crater, and some near Shindake Crater (just N of Furudake). Both the number and magnitude of the volcanic earthquakes increased on 9 June and remained elevated through 12 July; there were 151 events on 9 July, 319 on 10 July, 276 on 11 July, and 172 by 1500 on 12 July. The public was previously warned that ejected blocks and pyroclastic flows may affect areas within 2 km of Shindake, and at 1600 on 10 June the public was also warned to stay 2 km away from Furudake. The Alert Level remained at 3 (on a scale of 1-5).

Source: Japan Meteorological Agency (JMA)

PHIVOLCS reported that eruptive activity continued at Mayon during 5-11 July. Daily steam-and-gas emissions rose as high as 1 km above the crater and drifted in multiple directions. Average daily measurements of sulfur dioxide emissions fluctuated between 721 and 1,621 tonnes per day. Slow lava effusion from the summit crater continued to feed lava flows on the flanks. The length of the lava flow in the Mi-Isi (S) drainage remained at 2.8 km. The flow in the Bonga (SE) drainage advanced 100 m during 10-11 July, with a total length of 1.4 km. The growing lava dome remained unstable and produced incandescent rockfalls and pyroclastic density currents (PDCs, or pyroclastic flows) that descended the Basud (E) drainage as far as 4 km. Seismic stations recorded 216-511 daily rockfall events, 5-39 daily PDC events (from dome and lava front collapse) lasting 1-3 minutes, and 1-109 volcanic earthquakes. Ashfall was reported during 10-11 July in Legazpi City (13 km SSE), and Budiao (8.1 km S), Salvacion (8.6 km S), Daraga (12 km S), and Camalig (11 km SSW), in Albay. The Disaster Response Operations Monitoring and Information Center (DROMIC) reported that as of 1800 on 10 July, the number of displaced persons and total number of overall affected persons from 26 barangays in the province of Albay increased to 20,141 and 38,376, respectively. The Alert Level remained at 3 (on a 0-5 scale). Residents were reminded to stay away from the 6-km-radius Permanent Danger Zone (PDZ), and PHIVOLCS recommended that civil aviation authorities advise pilots to avoid flying close to the summit.

Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS), Disaster Response Operations Monitoring and Information Center (DROMIC)

JMA reported that at around 1300 on 9 July an eruption plume from Nishinoshima rose 1.6 km above the crater and drifted N. Satellite images acquired at 1420 and 2020 on 9 July and 0220 on 10 July showed continuing emissions rising 1.3-1.6 km and drifting NE and N.

Source: Japan Meteorological Agency (JMA)

OVPF reported that the eruption that began on 2 July at Piton de la Fournaise was ongoing during 5-11 July. Though there were multiple active fissures at the start of the eruption, as of 3 July only the SE flank fissure was active, located on the upper part of Grandes Pentes at approximately 1,720 m a.s.l. Volcano-tectonic earthquake events (VTs) fluctuated throughout the week but remained low relative to the onset of the eruption. The amplitude of the volcanic tremor dropped abruptly at 2105 on 4 July following a M 2.3 earthquake directly below Dolomieu Crater, and again on 7 July. Lava ejections continued to build a cone over the active vent throughout the week. During an overflight on 7 July, a team from OVPF-IPGP determined that the lava flow had reached 1.8 km from the road but had not advanced since 5 July. The flow front did not extend any further to the E, but by 7 July active flows were moving through a lava tube. During 10-11 July flows traveled through lava tubes and were active at elevations above 1,300 m. Although clouds often prevented measurements, satellite analysis showed that lava flow rates fluctuated between 1.5 and 24 cubic m/s. The total volume of lava effused since the beginning of the eruption was an estimated 5.5 million cubic m. Deflation of the whole edifice during 3-6 July ended by 8 July, and no significant deformation was observed the rest of the week.

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

SINAPRED reported that on 5 July a small explosion at San Cristóbal produced a moderately-sized ash-and-gas plume. The emissions in photos posted by SINAPRED appeared to be dense and gray, and pyroclastic flows were visible on the upper flanks. According to news articles, a strong sulfur odor was reported in nearby communities along with the fall of ash and larger tephra, most notably in La Grecia (12 km WSW). Fine ash particles in the air ash continued to impact residents the next day. A dark narrow deposit extending about 10 km W from the summit crater was visible in a 9 July Sentinel satellite image.

Sources: Sistema Nacional para la Prevención, Mitigación y Atención de Desastres (SINAPRED), La Prensa (Nicaragua), Sentinel Hub, European Pressphoto Agency

AVO reported that intermittent tremor and low-frequency earthquakes recorded at Shishaldin over the past week had gradually become more regular and consistent during 10-11 July. Strongly elevated surface temperatures at the summit were identified in satellite images during 10-11 July. The Volcano Alert Level was raised to Advisory (the second level on a four-level scale) and the Aviation Color Code was raised to Yellow (the second color on a four-color scale) at 1439 on 11 July, but AVO noted that the increased activity may or may not lead to an eruption.

Source: US Geological Survey Alaska Volcano Observatory (AVO)

IGP and INGEMMET reported that the eruption at Ubinas continued during 5-12 July. According to IGP there were 67 volcano-tectonic earthquakes indicating rock fracturing and 47 long-period earthquakes signifying the movement of gas and magma recorded during 5-9 July. A period of continuous ash-and-gas emissions was visible on 5 July with the plumes drifting more than 10 km SE and E. The Washington VAAC reported that ash plumes and periodic puffs of ash rose 5.5-9.1 km (18,000-30,000 ft) a.s.l. and drifted N and NE. On 6 July explosions recorded at 0747 and 2330 produced ash-and-gas plumes that rose as high as 3.5 km above the crater rim and drifted within 30 km NW, NE, SE, and S. According to the VAAC the explosion at 0747 produced a plume of ash and gas that rose to 9.1 km a.s.l., drifted SW, and gradually dissipated, while a lower-altitude plume at 7.6 km (25,000 ft) a.s.l. drifted NE. Gobierno Regional de Moquegua declared a state of emergency for districts in the Moquegua region, along with Coalaque Chojata, Icuña, Lloque, Matalaque (17 km SE), Ubinas, and Yunga of the General Sánchez Cerro province, to be in effect for 60 days.

On 7 July the VAAC reported that at 0320 an ash plume rose to 7.3 km (24,000 ft) a.s.l. and drifted E. At 0900 and 1520 steam plumes with diffuse ash rose to 6.7 km (22,000 ft) a.s.l. and drifted SE. Diffuse gas emissions were visible in satellite images drifting SE at 2120. Very small ash puffs visible in satellite and webcam images at 0920 and 1520 on 8 July rose as high as 6.4 km (21,000 ft) a.s.l. and drifted SE. INGEMMET reported that during 9-11 July sulfur dioxide emissions were low at 300 tons per day. Gas-and-steam plumes rose 150-400 m and drifted S. The Alert Level remained at Orange (the third level on a four-color scale) and the public was warned to stay 4 km away from the crater.

Sources: Instituto Geofísico del Perú (IGP), Instituto Geológico Minero y Metalúrgico (INGEMMET), Gobierno Regional de Moquegua, Washington Volcanic Ash Advisory Center (VAAC)