Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 2 March – 8 March 2022

Fuego – South-Central Guatemala : In a series of special bulletins, INSIVUMEH summarized increased activity at Fuego during 6-8 March that culminated in multiple pyroclastic flows and evacuations. A new period of effusion had begun on 5 March, resulting in a 300-m-long lava flow in the Ceniza drainage on the SSW flank. Explosions were weak to moderate in intensity, incandescent pulses were visible, and avalanches descended the Ceniza valley. Staff at the Observatorio Vulcanológico del Volcán de Fuego (OVFGO) in Panimaché I (8 km SW) noted that Strombolian activity intensified at around 1800 on 6 March. Incandescent material was ejected 200 m high and ash plumes rose along avalanches that traveled down the Ceniza and Trinidad (S) drainages. Rumbling sounds became more intense and frequent. By around 0930 on 7 March lava flows were 400 and 200 m long in the Ceniza and Santa Teresa ravines, respectively. Incandescent material was ejected 100-200 m high and avalanches descended the Ceniza, Trinidad, and Santa Teresa. By the afternoon activity again significantly increased based on both seismic and acoustic data as well as reports from observers at OVFGO and Observatorio Vulcanológico del Volcán de Agua (OVAGU). RSAM values increased just after 1200, peaking at a value just under 8,000, and notable pyroclastic flows were observed from OVFGO descending the Ceniza drainage at 1300. According to CONRED about 370 people were evacuated from Panimaché I and San Pedro Yepocapa (8 km NW). During the next hour larger, and more significant and frequent pyroclastic flows descended the Ceniza, sometimes spilling over the banks of the drainage. Ash fell in San Pedro Yepocapa and in other areas downwind. RSAM values decreased around 1400 but remained high. Pyroclastic flows continued to descend the drainage into the evening, and rumbling sounds, weak to moderate in intensity, were constantly audible. Weather clouds prevented clear views of the upper flanks. Ashfall was reported in Panimaché I and II, Morelia (9 km SW), Santa Sofía (12 km SW), Yucales, El Porvenir 8 km ENE), and Sangré de Cristo (8 km WSW). Between 1900-2200 RSAM values significantly increased and reached a peak value of around 14,000. Weather clouds cleared allowing for observations of the summit and upper flanks; pyroclastic flows continued to descend the Ceniza and avalanches and possible smaller pyroclastic flows traveled towards the Las Lajas drainage on the SE flank. A sulfur odor was reported in areas near the volcano and ash plumes drifted as far as 100 km NW and 40 km W and SW. Activity progressively declined during the morning of 8 March, with decreased effusion and eruption sounds; RSAM values declined by 0300 and remained low though 0735.

Kirishimayama – Kyushu (Japan) : JMA reported an increase in volcanic earthquakes just below Shinmoedake (Shinmoe peak, a stratovolcano of the Kirishimayama volcano group). A total of 17 events were recorded during 1-2 March, prompting JMA to raise the Alert Level to 2 (on a scale of 1-5) on 2 March. No changes were seen at the volcano during a field visit that same day. Volcanic earthquakes persisted, with 5-12 events per day recorded through 7 March. Emissions had risen no higher than 30 m above the crater rim since 1 January, and fumarolic plumes continued to rise no higher than 100 m from a fissure on the W flank. During a field survey conducted on 4 March at the base of the volcano, sulfur dioxide emissions were below the detectable limit and no changes to area hot springs were observed.

Langila – New Britain (Papua New Guinea) : The Darwin VAAC reported that on 6 March an ash plume from Langila rose 3 km (10,000 ft) a.s.l. and drifted SE. The plume had dissipated within an hour. On 8 March an ash plume rose to 3.7 km (12,000 ft) a.s.l. and drifted NW. Ash was no longer visible in satellite images within three hours.

Manam – Northeast of New Guinea : RVO reported that a small pyroclastic flow descending Manam’s flank was visually observed and recorded in webcam images at 0911 on 8 March. Minor ash emissions drifting NW were occasionally visible throughout the day. RSAM values sharply increased at 1900 coincident with escalating activity. An intense Strombolian phase at Southern Crater was observed during 1910-2030, characterized by loud roaring and rumbling heard on the mainland (22 km SW), bright summit incandescence, and ash emissions. The Alert Level was raised to Stage 3. The Darwin VAAC estimated that by 1950 the ash plume had risen as high as 15.2 km (50,000 ft) a.s.l. and drifted W. The plume had detached from the summit by 2050 and dissipated by 0050 on 9 March. Following the more intense eruptive phase, activity at Southern Crater was quiet and only white vapor emissions were visible. Observatory staff conducted a field visit the next day and noted no reports of roof collapses nor casualties in areas to the NW; vegetation including food crops were covered with ash.

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