Based on analyses of satellite imagery, the Washington VAAC reported that on 29 January an ash plume from Colima drifted 55 km NE at an uncertain altitude. A thermal anomaly was also detected.

According to news articles, residents up to 20 km away reported a loud noise, shaking ground, and rattling windows at about 0400 on 29 January. Colima ejected incandescent material and an ash plume that rose 3 km. Ash fell in several communities.

Sources: Washington Volcanic Ash Advisory Center (VAAC), El Economista, El Occidental, La Prensa (Mexico)

Sezione di Catania - Osservatorio Etneo reported that intense Strombolian activity at Etna's Bocca Nuova Crater began on the evening of 30 January and was the fifth episode of activity during a three-week interval that began on 10 January. Weak glow from a vent on the SE part of the crater floor was first observed at 1807. The glow became stronger and was visible to nearby residents; simultaneously volcanic tremor amplitude rapidly increased, and shifted from below the New Southeast Crater (NSEC) toward Bocca Nuova. Between 1900 and 1915 the activity intensified, and from 1920 onward jets of incandescent volcanic bombs and scoria nearly continuously rose higher than the crater rim. Some tephra was ejected 150 m above the rim.

During 1930-2000, lava fountains rose 100 m above the rim. Shortly after 2000, the fountain leaned SW and produced heavy fallout of incandescent bombs and scoria on the outer SW flank of the central summit cone, down to its base. At 2016 the fountain rose vertically and pyroclastic fallout outside the crater diminished.

Around 2030 the lava fountain started to wane; the incandescent jets became discontinuous and only rarely rose more than 100 m above the crater rim, except for one jet, at 2100, which rose 150 m above the rim. In addition, the volcanic tremor amplitude rapidly decreased and returned to normal levels in the late evening. After 2200, the incandescent pyroclastic jets no longer rose above the crater rim, and the glow became progressively less brilliant. During the night, however, weak eruptive activity continued on the crater floor, evident from a dull glow emanating from the crater. During the early morning hours of 31 January, the glow gradually faded away, and the episode ended with a series of sporadic, small ash emissions, the last of which was seen around 0641.

During 31 January-1 February ash emissions at New Southeast Crater (NSEC) were nearly continuous for intervals lasting from a few minutes to more than one hour. On 1 February small discrete "puffs" of ash rose from Bocca Nuova. At both craters ash plumes rose no higher than 100 m above the crater rims.

At 0300 on 2 February a camera recorded weak glow from NSEC then after 0330 sporadic small explosions ejected incandescent pyroclastic material up to a few tens of meters above the crater rim. The strongest explosions (at 0345, 0400, 0409, and 0411) ejected glowing bombs onto the flanks of the NSEC cone. Two minutes after the last of the explosions, weak glow appeared at Bocca Nuova that only lasted a short time; during the following 30 minutes, however, intermittent glow was recorded at both craters. At 0450 jets of lava rose above the rim of Bocca Nuova; at 0500 Strombolian activity became continuous, producing jest that rose many tens of meters above the rim. Small Strombolian explosions resumed in NSCE at 0512. Just after 0515 activity at Bocca Nuova started to increase rapidly; contemporaneously, the volcanic tremor amplitude showed a sharp rise. Lava fountains rose 120-150 m above the rim. Activity at NSEC started to decrease at 0530 then ceased just before 0600. Activity at Bocca Nuova decreased markedly between 0620 and 0630; weak intracrater activity continued for a few more hours and then by 0900 the episode was over.

Source: Sezione di Catania - Osservatorio Etneo (INGV)

According to news articles, an explosion from Paluweh occurred at 2300 on 2 February and was clearly heard by local residents. Authorities evacuated by boat all residents from the eight villages on the island. Ashfall was reported during 2-3 February.

Based on analyses of satellite imagery, wind data, and pilot reports, the Darwin VAAC reported that on 3 February ash plumes from Paluweh rose to altitudes of 13.1-13.7 km (43,000-45,000 ft) a.s.l. and drifted 325-590 km SE, S, and SW. Elevated levels of sulfur dioxide were also detected. The next day ash plumes at an altitude of 7.6 km (25,000 ft) a.s.l. were observed.

Sources: Darwin Volcanic Ash Advisory Centre (VAAC), TribunNews.com

According to a news report from 31 January, Tokua airport (20 km SE) reopened after being closed due to ash from Rabaul.

RVO reported that during 1-3 February Rabaul was mostly quiet, although occasional explosions produced light gray ash plumes that rose as high as 500 m above sea level and drifted E and ESE. At 1151 on 3 February an explosion produced a dense, dark ash plume that slowly rose 2 km above sea level and drifted ENE. Ash was observed falling on South Daughter (Turangunan, ~2 km to the E) and to the N of it. Dark gray ash emissions continued for the next 15-20 minutes. During the afternoon of 3 February through the morning of 4 February light gray ash emissions rose at irregular intervals and drifted E and ESE. White vapor plumes rose from the crater in between the ash emissions.

Sources: Rabaul Volcano Observatory (RVO), Radio Australia

During an overflight of Reventador on 29 January scientists observed an explosion and a steam-and-ash plume that rose 1.5 km above the lava dome. Since November the dome had significantly grown to at least 100 m higher than the E rim, and about 20 lava flows had traveled down the N, SE, and S flanks.

During 29 January-5 February seismicity remained high. Cloud cover often prevented observations although emissions were observed; steam-and-ash plumes rose 2-4 km and drifted W and NW on most days. Crater incandescence was observed at night during 29-30 January.

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

On 30 January GeoNet Data Centre reported that White Island's "hot lake" had dried up and a small tuff cone was forming on the former floor of the lake. The active vent continued to eject bursts of mud, rock, steam, and gas 50-100 m high. This activity along with the seismic activity was intermittent. Gas measurements taken during an overflight showed that the levels of volcanic gases emitted from the volcano were slightly higher than the levels measured the previous week: carbon dioxide gas flux increased from 1,800 to 2,000 tons/day, sulfur dioxide flux increased from 366 to 600 tons/day, and hydrogen sulfide flux was 19 tons/day (previously 15 tons/day). During 30-31 January seismicity changed to continuous tremor and remained at a high level. The Aviation Colour Code remained at Orange (second highest on a four-color scale) and the Volcanic Alert Level remained at 1 (on a scale of 0-5).

Source: GeoNet

JMA reported that during 28 January-1 February explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. Crater incandescence was occasionally detected.

The Tokyo VAAC reported that pilots observed ash plumes at altitudes of 3 km (10,000 ft) a.s.l. during 30-31 January. Based on information from JMA, explosions during 31 January-5 February generated plumes on most days that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted N, NW, and SE.

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

Based on analyses of satellite imagery and wind data, the Darwin Volcanic Ash Advisory Centre (VAAC) reported that on 29 January ash plumes from Batu Tara rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted E. Ash plumes rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted over 110 km W on 4 February and 55 km W on 5 February.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)

SVERT reported that steam-and-gas emissions from Snow, a volcano of Chirpoi, were detected in satellite images on 1 February; cloud cover prevented observations of the volcano on other days during 28 January-4 February.

Source: Sakhalin Volcanic Eruption Response Team (SVERT)

OVDAS-SERNAGEOMIN reported that during 29 January-4 February the web camera near Copahue recorded white gas plumes rising 350-1,550 m above the crater and drifting E and SE. Seismicity fluctuated but mostly remained at low levels. The Alert Level was lowered to Yellow on 4 February.

The Buenos Aires VAAC noted that although a pilot reported an ash plume between the altitudes of 3-4.6 km (10,000-15,000 ft) a.s.l., no ash was detected in mostly clear satellite images. The VAAC also noted that steam with possible diffuse ash was recorded by the OVDAS webcam.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Buenos Aires Volcanic Ash Advisory Center (VAAC)

KVERT reported that weak seismic activity at Karymsky was detected during 25 January-1 February. Satellite imagery showed a thermal anomaly on the volcano during 24-25 and 30 January. The Aviation Color Code remained at Orange.

Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 30 January an ash plume rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted SE. An ash plume was not detected in satellite imagery.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)

During 30 January-5 February HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kīlauea's Halemaʻumaʻu Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas. The lake level was 32 m below the Halemaʻumaʻu crater floor on 31 January.

At Puʻu ʻŌʻō Crater, glow emanated from spatter cones on the SE part of the crater floor, from a spatter cone at the NW edge of the floor, and from a perched circulating lava lake on the NE part of the floor. Lava flows were active in a 1-km-wide area on the coastal plain. Web cameras recorded steam plumes from lava sporadically entering the ocean at multiple locations. Lava from the lava lake (perched 5-6 m higher than the crater rim) flowed across the NE flank of Puʻu ʻŌʻō cone to the cone's base and continued to advance over older flows. On 31 January the N spatter cone gushed with lava; the flow quickly banked against the N crater wall, advanced E to the base of the perched pond at the NE edge, and W towards the W crater wall. On 4 February a minor amount of lava flowed out of the SW spatter cone, and a brief but voluminous lava flow gushed out of the NW spatter cone on 5 February.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)

KVERT reported that during 25 January-1 February moderate seismic activity continued at Kizimen. Video data showed that lava continued to extrude from the summit onto the E and SE flanks. Summit incandescence, strong gas-and-steam activity, and occasional hot avalanches on the W and E flanks accompanied the process. Satellite images detected a daily thermal anomaly over the volcano. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

According to news articles, Lokon-Empung erupted twice on 31 January, producing an ash plume that rose 800 m after the first eruption. Seismicity had increased the day before. In another article the head of the Lokon observation post reported that eruptions from Lokon occurred daily, and specifically that nine eruptions had occurred on 2 February.

Based on a ground report from CVGHM, the Darwin VAAC reported that an ash plume from Lokon-Empung rose to an altitude of 4 km (13,000 ft) a.s.l. on 3 February. Ash was not detected in satellite imagery.

Sources: People's Daily Online (China), Darwin Volcanic Ash Advisory Centre (VAAC), Kompas.com

On 30 January, INSIVUMEH reported that both an increasing height of ash plumes from explosions at Santiaguito lava-dome complex and a change in wind direction caused ashfall in the towns of Esperanza and San Mateo in Quetzaltenango. Dark gray plumes rose an average of 800 m above the complex and were accompanied by sulfur dioxide emissions.

During 30-31 January a series of small explosions produced ash plumes that rose 300 m and drifted NW. Active lava flows produced avalanches. During 31 January-1 February ashfall was reported in areas to the S. Two explosions on 3 February generated ash plumes that rose 700 m above the complex and drifted SW. Noise from avalanches were reported on 4 February. Two explosions on 5 February generated white-and-gray plumes that rose 700 m and drifted SW, causing ashfall in areas downwind.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)

Based on visual observations and analyses of satellite data, KVERT reported that during 25 January-1 February a viscous lava flow effused on the E flank of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Satellite imagery showed a daily thermal anomaly on the lava dome. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a lava plateau on the SW side of Tolbachik, continued to produce very fluid lava flows during 25 January-1 February that traveled to the W and S sides of Tolbachinsky Dol. Four cinder cones continued to grow on the S fissure above Krasny cone. Gas-and-ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. and drifted in multiple directions. A very large thermal anomaly on the N part of Tolbachinsky Dol was visible daily in satellite imagery. The Aviation Color Code remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)