Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the Week 2 June – 8 June 2021

Aira – Kyushu (Japan) : JMA reported that during 31 May-7 June incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly and very small eruptive events were occasionally recorded. The sulfur dioxide emission rate was 2,700 tons per day on 2 June. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Ebeko – Paramushir Island (Russia) : According to volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, an explosion on 28 May produced an ash plume that rose to 4.5 km (10,500 ft) a.s.l. and drifted NE. A thermal anomaly was identified in satellite images on 2 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Etna – Sicily (Italy) : INGV reported a few eruptive episodes at Etna’s Southeast Crater (SEC) during 31 May-6 June, as well as minor and diffuse ash emissions at Bocca Nuova (BN) and ash emissions on 4 June at Northeast (NEC). Weak Strombolian activity at SEC began at 0850 on 2 June and produced minor and diffuse ash plumes. The activity intensified at 1000; within 30 minutes lava fountaining was observed and lasted for over two hours. Ash plumes rose 5-6 km (16,400-19,700 ft) a.s.l. and drifted E, causing ashfall in Petrulli, Santa Venerina, and in an areas N of Zafferana. Lava overflowed the S side of the crater and traveled W. Fountaining stopped at 1245. Weak Strombolian activity continued to be observed during the night hours of 3-4 June. Activity increased at 1530 on 4 June and was characterized by discontinuous ash emissions and lava overflowing the S rim of SEC. Lava fountaining began at 1820 and an ash plume rose to 6.5 km (21,300 ft) a.s.l. Tephra fell in Aci Castello, Acitrezza, San Giovanni La Punta, Tremestieri, Catania, and Viagrande, and between Pedara, Fleri, and Siracusa. Fountaining began to decline at 1930. The lava flow continued to advance, and by 2300 had reached 2,800 m elevation. Occasional ash emissions were noted during 4-5 June, and the lava flow had ceased.

Fuego – Guatemala : INSIVUMEH reported that 5-13 explosions per hour were recorded during 1-8 June at Fuego, generating ash plumes as high as 1.1 km above the crater rim. Shock waves often rattled buildings around the volcano. Ashfall was reported almost daily in several areas downwind, including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Sangre de Cristo (8 km WSW), and San Pedro Yepocapa (8 km NW). Block avalanches descended the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Las Lajas (SE), and Honda drainages, often reaching vegetated areas. Explosions ejected incandescent material 100-350 m above the summit on most days.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was visible in satellite images during 28-31 and 2-3 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kerinci – Indonesia : The Darwin VAAC reported that on 6 June an ash plume from Kerinci rose to 4 km (13,000 ft) a.s.l. and drifted WNW. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.

Krysuvik-Trolladyngja – Iceland : The fissure eruption in the W part of the Krýsuvík-Trölladyngja volcanic system, close to Fagradalsfjall on the Reykjanes Peninsula, continued during 2-8 June. The flow rate at the fifth vent, now the main lava source, was 12.4 cubic meters per second by 3 June, similar to the 11-13 cubic meters per second measured in May. Cycles of lava fountaining followed by no activity persisted at the fifth vent, though observers noted that the vent opening was getting smaller as the crater walls thickened. One observer described standing waves of lava 20 m high during a period of greater lava effusion. Lava advanced in the Nátthaga, Geldingadalur, and Merardalur valleys. The flows in Nátthaga continued to get closer to Highway 427 (Suðurstrandarvegur) to the S, covering an area with buried fiber optic communication cables. The leading edge of the flow ignited vegetation, causing small fires. The Aviation colour Code remained at Orange due to the lack of ash and tephra emissions, though IMO warned of the potential for lapilli and scoria fallout within a 650 m radius of the active vent. Authorities warned of increased gas emissions hazards.

Lewotolok – Lembata Island (Indonesia) : PVMBG reported that white-and-gray plumes from Lewotolok rose as high as 500 m and drifted W and E almost daily during 1-8 June. Rumbling was heard every day. Crater incandescence was visible during 1 and 3-4 June. Incandescent material was ejected as far as 300 m in all directions during 3-4 June and as far as 1 km NW during 5-6 June. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.

Merapi – Central Java (Indonesia) : PVMBG reported that the eruption at Merapi continued during 1-8 June. As many as 16 daily incandescent avalanches were recorded, traveling as far as 2 km down the SW flank. Pyroclastic flows traveled as far as 1.6 km down the SW flank during 5-8 June. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to stay outside of the 3-km exclusion zone.

Nevados de Chillan – Chile : SERNAGEOMIN reported continuing explosive and effusive activity at Nevados de Chillán’s Nicanor Crater during 16 May-2 June, and increased sulfur dioxide emissions and thermal anomalies. Explosions partly destroyed the dome, generating ash plumes that rose as high as 1.4 km above the crater rim and pyroclastic flows that traveled as far as 1.1 km down the NE flank. Satellite images indicated that the L5 lava flow did not lengthen, remaining at 966 m, though the distal part of the flow widened. The L6 lava flow advanced at a rate of 1.16 m per hour to over 890 m long. The average temperature was 101 degrees Celsius with a maximum of 264 for L5 and an average of 121 degrees Celsius with a maximum of 293 for L6. A new lobate flow emerged just to the N of L6; measurements on 2 June indicated that the temperature of the flow was similar to that of L6. Data indicated that the lava dome in Nicanor Crater did not get larger. The average sulfur dioxide emission rate was 706 (± 216) tons/day, reaching a high value of 1,101 on 27 May. The number and intensity of thermal anomalies increased, and were notable on 20, 23, 25, 28, and 30 May, likely due to the active lava flows. The Alert Level remained at Yellow, the second lowest level on a four-colour scale. ONEMI stated that Alert Level Yellow (the middle level on a three-colour scale) remained in place for the communities of Pinto and Coihueco, noting that the public should stay at least 2 km away from the crater.

Popocatepetl – Mexico : CENAPRED reported that each day during 2-8 June there were 87-136 steam-and-gas emissions with minor amounts of ash from Popocatépetl and periods of low-amplitude tremor lasting from five minutes to about three hours and 40 minutes. Minor crater incandescence was visible overnight during most nights. The Alert Level remained at Yellow, Phase Two (middle level on a three-colour scale).

Reventador – Ecuador : IG reported that a high level of activity continued to be recorded at Reventador during 1-8 June; adverse weather conditions sometimes prevented visual confirmation. Seismicity was characterized by 3-23 daily explosions, volcano-tectonic and harmonic tremor events, long-period earthquakes, and signals indicating emissions. Gas, steam, and ash plumes, often observed multiple times a day with the webcam or reported by the Washington VAAC, rose higher than 1 km above the summit crater and drifted mainly W, NW, and NE. Crater incandescence and incandescent blocks rolling as far as 500 m down the S flank were occasionally observed at night. Lava flows on the N, NE, SE, and S flanks were active. The report also noted that a bulging area on the N flank first detected on 13 May had persisted.

Santa Maria – Guatemala : INSIVUMEH reported that during 1-8 June daily explosions at Santa María’s Santiaguito lava-dome complex generated ash plumes that rose as high as 1.1 km above the summit and drifted SE, SW, and W. Collapses of blocky lava from Caliente dome sent avalanches down the S, SW, and W flanks, sometimes reaching the base, and caused minor ashfall mostly on the volcano’s flank. Ashfall was also reported in San Marcos (8 km SW) and Loma Linda Palajunoj (6 km WSW) during 4-5 June.

Semeru – Eastern Java (Indonesia) : PVMBG reported that Semeru continued to erupt during 1-8 June. Inclement weather often prevented visual observations, through gray-and-white plumes were visible on 3 and 6 June rising 200-500 m above the summit and drifting S and SW. The Darwin VAAC reported that during 2, 5-6, and 8 June ash plumes rose as high as 4.3 km (14,000 ft) a.s.l., or about 600 m above the summit, and drifted SE, SW, W, and NW. The Alert Level remained at 2 (on a scale of 1-4), with a general exclusion zone of 1 km and extensions to 5 km in the SSE sector.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 28 May-4 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Sinabung – Indonesia : PVMBG reported that the eruption at Sinabung continued during 2-8 June. An eruptive event was recorded at 2004 on 3 June but not visually confirmed due to inclement weather. Another event, at 2335 on 6 June, produced ash plumes and pyroclastic flows, though weather again inhibited visual observations. The Darwin VAAC reported that an ash plume rose to 9.1 km (30,000 ft) a.s.l. and drifted W and SW. Ash continued to be identified in satellite images; the next day ash clouds drifted W and WSW at 9.1 km, W at 7.3 km (24,000 ft) a.s.l., WNW at 6.1 km (20,000 ft) a.s.l., and N at 4.3 km (14,000 ft) a.s.l. The Alert Level remained at 3 (on a scale of 1-4), with a general exclusion zone of 3 km and extensions to 5 km in the SE sector and 4 km in the NE sector.

Whakaari/White Island – North Island (New Zealand) : According to GeoNet water filled in the vents of Whakaari/White Island’s 2019 Primary Crater based on 18 May webcam views. During an observation overflight on 27 May scientists confirmed the new lakelet and noted that several active steam and gas vents were under water. Thermal infrared measurements indicated that temperatures had cooled significantly. Gas emissions had not notably changed over the previous few months. A persistent gas-and-steam plume likely produced acid rain on the island. A period of low-energy volcanic tremor began at around 0400 on 1 June and lasted for two hours. Activity rapidly returned to low levels afterwards. Overall, seismicity was at background levels. The Volcanic Alert Level remained at 1 and the Aviation colour Code remained at Green.

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