According to the Vanuatu Geohazards Observatory, Ambanga villagers reported that minor activity at Aoba began in December 2012. The OMI instrument detected strong gas emissions on 18 and 25 January; the emissions continued at a lower level through 7 February. Field observations by the Geohazards team during 30 January-2 February confirmed that activity had significantly changed. Data retrieved from a monitoring station also confirmed ongoing activity. The Vanuatu Volcano Alert Level (VVAL) remained at 1 (on a scale of 0-4).

Source: Vanuatu Meteorology and Geohazards Department (VMGD)

On 6 February AVO reported that satellite imagery acquired on 30 January indicated that a lava dome had grown in Cleveland's summit crater, prompting AVO to raise the Volcanic Alert Level to Watch and the Aviation Color Code to Orange. The dome was about 100 m in diameter and may have begun forming as early as 24 January when elevated surface temperatures were observed in satellite images. The size and shape of the dome appeared to be unchanged based on satellite data acquired on 2 February. Elevated surface temperatures from the lava dome were detected during 5-6 and 8-11 February.

Source: US Geological Survey Alaska Volcano Observatory (AVO)

Sezione di Catania - Osservatorio Etneo reported that during the days following the 2 February eruptive episode at Etna intermittent emissions of small quantities of ash were repeatedly observed from both the New Southeast Crater (NSEC) and Bocca Nuova Crater.

Volcanologists visited Etna on 5 February and observed the recent changes that had taken place at Bocca Nuova Crater, notably the growth of a pyroclastic cone surrounding the eruptive vent in the SE portion of the crater. This cone had grown at least 50-70 m, about halfway up the inner crater wall, and was leaning into the wall. The entire crater floor was covered with recent lava.

Later in the evening of 5 February a webcam recorded weak Strombolian activity at NSEC, which continued until daybreak the next day, and then became invisible due to deteriorating weather conditions. Seismic data showed an instantaneous increase of tremor at 1020; volcanic tremor amplitude rose to a peak within a few minutes after the start of the activity, and began to descend after less than one hour. People in the ski area on the NE flank of the volcano briefly saw a dense but ash-free gas plume rising from the summit.

After the episode on 6 February through most of 8 February sporadic ash emissions from NSEC were observed, although poor weather conditions often prevented observations. On the evening of 8 February weak glow from NSEC was intermittently visible. At 2100 a webcam recorded fluctuating glow from within Bocca Nuova which became more intense over the next 10 minutes. Around 2125 jets of incandescent lava were repeatedly seen rising above a thick blanket of clouds drifting over the summit area of Etna. Contemporaneously, the volcanic tremor amplitude rose sharply. After 2200 the volcanic tremor amplitude began to decrease, whereas the eruptive activity continued without showing signs of diminishing until about 30 minutes later. After 2230 on 8 February and during 9-10 cloud cover prevented observations. A brief ash emission was observed on 10 February.

Source: Sezione di Catania - Osservatorio Etneo (INGV)

RVO reported that during 4-5 February pale gray ash plumes rose from Rabaul caldera's Tavurvur cone. On 5 February the ash plumes slowly rose 2 km a.s.l. and drifted E and ENE. On 6 February only white plumes rose from the crater during most of the day. In the evening a gray billowing ash cloud was followed by a sequence of "gentle puffs" of white to light gray ash emissions at irregular intervals into the night and through the morning of 7 February. Fine ashfall was reported in Rabaul town (3-5 km NW) in the late evening of 6 February.

Source: Rabaul Volcano Observatory (RVO)

SVERT reported that a thermal anomaly over Rasshua was detected in satellite images on 6 February.

Source: Sakhalin Volcanic Eruption Response Team (SVERT)

IG reported that seismicity at Reventador was high during 6-7 February and moderate during 8-12 February; explosions were detected daily. An ash plume rose 3 km and drifted S on 7 February, and ashfall was reported in areas near the volcano on 9 February. Cloud cover often prevented observations.

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

MVO reported that during 1-8 February activity at the Soufrière Hills lava dome was at a low level, although there was a slight increase during 3-6 February characterized by volcano-tectonic earthquakes, elevated gas flux, and possible light ash venting. The volcano-tectonic earthquakes occurred in four brief swarms: at 2220 on 3 February, at 0915 and 0950 on 4 February, and at 0620 on 5 February. The second swarm was the most intense, and was followed by a hybrid seismic event. Another hybrid event was not associated with a swarm.

After the second, and largest, volcano-tectonic swarm on 4 February, there were increases in the temperatures of several fumaroles inside the 11 February 2010 collapse scar, as observed using a handheld thermal infra-red camera at MVO, 5.7 km away. There was a further increase, as well as some loud roaring sounds, around the time of the third swarm. The activity likely included minor ash venting from a large fumarole in the floor of the collapse scar because fresh ash deposits were observed adjacent to this fumarole on the morning of 5 February. All fumaroles had returned to background levels of activity and temperature by later that day.

Sulfur dioxide measurements showed an average flux of 929 tonnes/day during the week, with a maximum of 2,381 tonnes/day and a minimum of 273. The flux was not steady, with peaks of 962, 1,266 and 2,381 on 1, 4 and 6 February, respectively. The last measurement is the highest daily value since the ash-venting episode that occurred during 23-25 March 2012. The Hazard Level remained at 2 (on a scale of 1-5).

Source: Montserrat Volcano Observatory (MVO)

On 9 February Sezione di Catania - Osservatorio Etneo reported that after about three weeks of normal explosive activity, new, small lava overflows again occurred on Stromboli's crater terrace. The first overflow started in the morning of 8 February, producing a small lava flow that descended the upper NW slope of the Sciara del Fuoco, and ceased during the afternoon. The second overflow began shortly after midnight on 9 February and produced a lava flow that traveled N. Bad weather prevented surveillance video transmission after 0125; when the transmission resumed at 1000, the feeding of the lava flow had diminished, and the active flow front was retreating upslope, generating frequent rockfalls. In the late afternoon of 9 February lava effusion ceased altogether, but resumed once more during the early morning hours of 10 February, generating a small flow that slowly advanced downslope for a few tens of meters. The lava front continuously produced incandescent rockfalls. During the day, lava emission progressively diminished, and ceased completely in the late afternoon.

Source: Sezione di Catania - Osservatorio Etneo (INGV)

On 11 February GeoNet Data Centre reported that analysis of recent changes and measurements from White Island indicated that activity was lower than the previous week; therefore, the Aviation Colour Code was lowered to Yellow and the Volcanic Alert Level remained at 1 (on a scale of 0-5). The report also stated that early during the previous week the level of volcanic tremor recorded at White Island dropped to less than half that of the week before. At the same time small explosive eruptions in the active crater, which had been occurring for about three weeks, became less intense. On 7 February sulfur dioxide and carbon dioxide gas measurements were similar to measurements from January: sulfur dioxide flux was 560 tonnes/day and carbon dioxide flux was 1,800 tonnes/day. A volcanologist that visited the lake area on 8 February noted that water had again filled the lake and small geysering was the only activity that he observed. The lake water was hot, about 80 degrees Celsius.

Source: GeoNet