JMA reported that during 17-21 February three explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that explosions during 19-20 and 22-25 February generated ash plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted NE, SE, and S. A pilot observed ash on 20 February.

Sources: Japan Meteorological Agency (JMA), Tokyo Volcanic Ash Advisory Center (VAAC)

JMA reported that a very small explosion from Asosan's Nakadake Crater occurred on 19 February. An off-white plume rose 200 m above the crater rim and drifted SW. During fieldwork on 21 February volcanologists noted that sulfur dioxide emissions remained high. The Alert Level remained at 2 (on a scale of 1-5).

Source: Japan Meteorological Agency (JMA)

PVMBG reported that on 14 February, the day after a large eruption at Kelut that began at 2250 on 13 February, gray-to-black plumes rose 400-600 m above the crater. On 15 February grayish white plumes rose as high as 3 km. During 16-20 February white plumes rose as high as 1 km and drifted N, NE, and E. Heavy rain on 18 February caused lahars in Ngobo, Mangli (Kediri, 35 km WNW), Bladak (Blitar, 20 km SW), and Konto (Malang, 35 km E). BNPB noted that the lahars flooded five houses and one mosque, and destroyed two homes and one bridge.

The report noted that four out of the five seismic stations monitoring Kelut were destroyed during the eruption. The one remaining station, 5 km away, recorded declining seismicity during 14-20 February. Two more seismic stations were installed, 2-3 km from the crater, on 16 February. The Alert Level was lowered to 3 on 20 February. Visitors and residents were prohibited from approaching the crater within a radius of 5 km; residents outside of the 5-km restricted zone were permitted to return home.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Badan Nacional Penanggulangan Bencana (BNPB)

According to a news article from 5 February four explosions from Marapi occurred in early February. One of the explosions was followed by ashfall in the Tarab River area and Batu Sangkar (17 km SE).

Source: Metro TV News

CENAPRED reported that at 0944 on 19 February a gas-and-vapor plume containing moderate amounts of ash rose 1.5 km above Popocatépetl's crater and drifted NE and SW. At 2338 a gas-and-vapor plume containing small amounts of ash rose 1 km and drifted E. A small explosion at 0409 on 21 February ejected incandescent tephra which mostly fell back inside the crater, and produced an ash plume that rose 2 km. An explosion at 1233 ejected incandescent tephra 600 m from the crater rim. An ash plume rose 4 km and drifted NE. Another explosion at 1541 produced an ash plume with lower ash content that rose 2 km and also drifted NE. At 0312 on 22 February an explosion generated an ash plume that rose 2 km and drifted SE. Explosions at 0615 and 0619 ejected incandescent tephra and produced ash plumes that rose 1 km and drifted SE. On 25 February steam-and-gas plumes drifting SE were occasionally seen during times of good visibility. The Alert Level remained at Yellow, Phase Two.

Source: Centro Nacional de Prevencion de Desastres (CENAPRED)

IG reported that activity at Tungurahua was at moderate-to-high levels during 19-25 February; cloud cover often prevented observations. On 20 February ash plumes rose 2-3.5 km above the crater and drifted SW. Ashfall was reported in Píllate (8 km W), Quero (20 km NW), and Tizaleo (29 km NW). The next day observers reported blocks rolling down the flanks. Ash fell in Píllate on 23 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)

SVERT reported that a thermal anomaly over Chirinkotan was observed in satellite images on 20 February. Cloud cover obscured views on other days during 17-24 February. The Aviation Color Code remained at Yellow.

Source: Sakhalin Volcanic Eruption Response Team (SVERT)

SVERT reported that a thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images during 19-20 February. Cloud cover obscured views on the other days during 17-24 February. The Aviation Color Code remained at Yellow.

Source: Sakhalin Volcanic Eruption Response Team (SVERT)

AVO reported that small explosions from Cleveland were detected by infrasound and lightning alarms at 1917 on 24 February and 0135 on 25 February. Small ash clouds from the explosions were detected in satellite images several hours after the events drifting at an altitude of about 5 km (16,000 ft) a.s.l. The Volcanic Alert Level remained at Advisory and the Aviation Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)

Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 20 and 22-23 February ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 55-150 km E, SE, and SSE.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)

INGV reported that during 19-22 February Strombolian activity continued at Etna's New Southeast Crater (NSEC) and produced diffuse ash plumes. Lava continued to flow from a vent on the lower part of the NSEC cone to the W wall of the Valle del Bove. An unstable part of the lower E flank of the cone that collapsed on 11 February continued to produce small collapses with reddish ash clouds, and thermal anomalies.

Source: Sezione di Catania - Osservatorio Etneo (INGV)

KVERT reported that Vulcanian and Strombolian activity at Karymsky continued during 14-21 February. Satellite images detected a daily thermal anomaly on the volcano. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

During 19-25 February HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kīlauea's Halemaʻumaʻu Crater. Gas emissions remained elevated. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. At Puʻu ʻŌʻō Crater, glow emanated from spatter cones on the N and S portions of the crater floor, and a lava pond was active in the NE spatter cone. The 7.8-km-long Kahauale’a 2 lava flow, fed by the NE spatter cone, stalled in mid-January but remained active with scattered break-out flows behind the flow front that burned adjoining forest.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)

Based on analyses of satellite images, the Buenos Aires VAAC reported that on 24 February a diffuse plume possibly containing ash from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, was lifted from the surface by the wind.

Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)

KVERT reported that during 14-21 February lava-dome extrusion at Shiveluch was accompanied by ash explosions, incandescence, and fumarolic activity. A thermal anomaly was detected daily in satellite images. On 19 February a gas-and-steam plume containing small amounts of ash rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted about 50 km SSE. On 25 February satellite images detected ash plumes that rose to altitudes of 4-4.5 km (13,100-14,800 ft) a.s.l. and drifted SE. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

On 19 February BNPB reported that villagers outside of the 5-km evacuation zone around Sinabung continued to return to their homes. Based on wind data and satellite images, the Darwin VAAC reported that during 19 and 21-22 February ash plumes rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted 25-35 km NE and SW. Ash plumes were visible in webcam images during 23-25 February; ash plumes rose to altitudes of 3.7-4.6 km (12,000-15,000 ft) a.s.l. on 25 February and drifted 45 km E. On 24 February BNPB noted that 16,361 people remained in 34 evacuation shelters. Dense white plumes rose 100-300 m above the dome and incandescent material as far as 2 km SE from the dome was observed.

Sources: Badan Nacional Penanggulangan Bencana (BNPB), Darwin Volcanic Ash Advisory Centre (VAAC)

The Tokyo VAAC reported an explosion from Suwanosejima on 19 February. Explosions during 23-24 February produced plumes that rose to an altitude of 1.8 km (6,000 ft) a.s.l. An ash plume on 24 February drifted E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)