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Smithsonian / USGS Weekly Volcanic Activity Report

Weekly Volcanic Activity Map

The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday and averaging 16 reported volcanoes, this is not a comprehensive list of all eruptions this week, but rather a summary of activity that meet criteria discussed in the "Criteria and Disclaimers" section below.

Volcanic activity reported here is preliminary and subject to change. Carefully reviewed, detailed narratives over longer time periods are published as reports of the Bulletin of the Global Volcanism Network available through volcano profile pages.

Smithsonian / USGS Weekly Volcanic Activity Report for the week of 18 August-24 August 2021
Name Location Eruption Start Date Report Status
Chirinkotan Kuril Islands (Russia) New
Fagradalsfjall Iceland New
Fukutoku-Oka-no-Ba Volcano Islands (Japan) New
Kilauea Hawaiian Islands (USA) New
Pavlof Alaska Peninsula, Alaska New
Whakaari/White Island North Island (New Zealand) New
Atka Volcanic Complex Andreanof Islands (USA) Continuing
Ebeko Paramushir Island (Russia) 2022 Jun 11 Continuing
Fuego South-Central Guatemala 2002 Jan 4 Continuing
Great Sitkin Andreanof Islands (USA) 2021 May 25 Continuing
Ibu Halmahera 2008 Apr 5 Continuing
Kadovar Northeast of New Guinea Continuing
Karymsky Eastern Kamchatka (Russia) Continuing
Langila New Britain (Papua New Guinea) 2015 Oct 22 (?) Continuing
Lewotolok Lembata Island 2020 Nov 27 Continuing
Merapi Central Java 2020 Dec 31 Continuing
Pacaya South-Central Guatemala Continuing
Reventador Ecuador 2008 Jul 27 Continuing
Sangay Ecuador 2019 Mar 26 Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
Semeru Eastern Java 2017 Jun 6 Continuing
Semisopochnoi Aleutian Islands (USA) Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 Continuing
Taal Luzon (Philippines) Continuing
Tengger Caldera Eastern Java Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,019 individual reports over 1,216 weeks (average of 16 per week) on 332 different volcanoes.

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Agung Cuicocha Iliwerung Llaima Popocatepetl Sumbing
Ahyi Cumbal Inielika Lokon-Empung Purace Sundoro
Aira Dabbahu Ioto Lonquimay Puyehue-Cordon Caulle Suretamatai
Akan Davidof Irazu Lopevi Rabaul Suwanosejima
Alaid Dempo Iya Machin Raikoke Taal
Alu-Dalafilla Descabezado Grande Izu-Torishima Makushin Ranakah Tair, Jebel at
Ambae Dieng Volcanic Complex Jackson Segment Maly Semyachik Raoul Island Takawangha
Ambang Dukono Kaba Manam Rasshua Talang
Ambrym East Epi Kadovar Manda Hararo Raung Tambora
Anatahan Ebeko Kaitoku Seamount Marapi Redoubt Tanaga
Aniakchak Ebulobo Kama'ehuakanaloa Maroa Reventador Tandikat-Singgalang
Antillanca Volcanic Complex Edgecumbe Kambalny Martin Reykjanes Tangkoko-Duasudara
Antuco Egon Kanaga Masaya Rincon de la Vieja Tangkuban Parahu
Apoyeque Ekarma Kanlaon Maule, Laguna del Rinjani Tara, Batu
Arenal Eldey Karangetang Mauna Loa Ritter Island Ta'u
Asamayama Erebus Karkar Mayon Rotorua Taupo
Askja Erta Ale Karthala McDonald Islands Ruang Telica
Asosan Etna Karymsky Melebingoy Ruapehu Tenerife
Atka Volcanic Complex Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruby Tengger Caldera
Augustine Eyjafjallajokull Katla Merapi Ruiz, Nevado del Three Sisters
Avachinsky Fagradalsfjall Katmai Midagahara Sabancaya Tinakula
Awu Fernandina Kavachi Misti, El Sakar Tofua
Axial Seamount Fogo Kelimutu Miyakejima Salak Tokachidake
Azul, Cerro Fonualei Kelud Momotombo San Cristobal Tolbachik
Azumayama Fournaise, Piton de la Kerinci Monowai San Miguel Toliman
Bagana Fourpeaked Ketoi Montagu Island San Vicente Tongariro
Balbi Fuego Kharimkotan Moyorodake [Medvezhia] Sangay Trident
Bamus Fujisan Kick 'em Jenny Mutnovsky Sangeang Api Tungurahua
Banda Api Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Ana Turrialba
Bardarbunga Galeras Kikai Nabro Santa Maria Ubinas
Barren Island Galunggung Kilauea Negra, Sierra Sao Jorge Ugashik-Peulik
Batur Gamalama Kirishimayama Negro, Cerro Sarigan Ukinrek Maars
Bezymianny Gamkonora Kita-Ioto Nightingale Island Sarychev Peak Ulawun
Bogoslof Gareloi Kizimen Nishinoshima Saunders Unnamed
Brava Gaua Klyuchevskoy Nisyros Savo Unnamed
Bristol Island Gorely Kolokol Group Novarupta Semeru Veniaminof
Bulusan Great Sitkin Koryaksky NW Rota-1 Semisopochnoi Villarrica
Calbuco Grimsvotn Krakatau Nyamulagira Seulawah Agam Vulcano
Callaqui Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Sheveluch West Mata
Cameroon Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Shishaldin Westdahl
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Okataina Simbo Whakaari/White Island
Cayambe Hachijojima Kurikomayama Okmok Sinabung Witori
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Ontakesan Sinarka Wolf
Chaiten Heard Kverkfjoll Oraefajokull Siple Wrangell
Chiginagak Hekla La Palma Osorno Sirung Yakedake
Chikurachki Helgrindur Lamington Pacaya Slamet Yasur
Chiles-Cerro Negro Hierro Lamongan Pagan Snaefellsjokull Yufu-Tsurumi
Chillan, Nevados de Hokkaido-Komagatake Langila Palena Volcanic Group Soputan Zaozan [Zaosan]
Chirinkotan Home Reef Lanin Paluweh Sorikmarapi Zavodovski
Chirpoi Hood Lascar Panarea Sotara Zhupanovsky
Ciremai Huaynaputina Late Papandayan Soufriere Hills Zubair Group
Cleveland Hudson, Cerro Lateiki Pavlof Soufriere St. Vincent
Colima Huila, Nevado del Lengai, Ol Doinyo Pelee South Sarigan Seamount
Colo Hunga Tonga-Hunga Ha'apai Leroboleng Peuet Sague Spurr
Concepcion Ibu Lewotobi Pinatubo St. Helens
Copahue Ijen Lewotolok Planchon-Peteroa Stromboli
Cotopaxi Iliamna Little Sitkin Poas Sulu Range
 News Feeds and Google Placemarks


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The RSS (Really Simple Syndication) feed is identical to the Weekly Volcanic Activity Report minus some features including the header information (latitude and longitude and summit elevation), the Geologic Summary, and a link to the volcano's page from the Global Volcanism Program. At the end of each report is a list of the sources used. Each volcano report includes a link from the volcano's name back to the more complete information in the Weekly Volcanic Activity Report on the Smithsonian website. This feature was first made available on 5 March 2008.



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A Google Earth network link for the Weekly Volcanic Activity Report can be loaded into the free Google Earth software, and in turn will load placemarks for volcanoes in the current weekly report. Placemark balloons include the volcano name, report date, report text, sources, and links back to the GVP volcano profile page and to the complete Weekly Report for that week. This feature was first made available on 1 April 2009.

 Criteria & Disclaimers

Criteria



The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:

- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.

Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.

It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.

Disclaimers



1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are cover longer time periods and are more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.

2. Rapidly developing events lead to coverage that is often fragmentary. Volcanoes, their eruptions, and their plumes and associated atmospheric effects are complex phenomena that may require months to years of data analysis in order to create a comprehensive summary and interpretation of events.

3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.

4. Many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source.

5. USGS Disclaimer Statement for this Website:

Information presented on this website is considered public information and may be distributed or copied. Use of appropriate byline/photo/image credit is requested. We strongly recommend that USGS data be acquired directly from a USGS server and not through other sources that may change the data in some way. While USGS makes every effort to provide accurate and complete information, various data such as names, telephone numbers, etc. may change prior to updating. USGS welcomes suggestions on how to improve our home page and correct errors. USGS provides no warranty, expressed or implied, as to the accuracy, reliability or completeness of furnished data.

Some of the documents on this server may contain live references (or pointers) to information created and maintained by other organizations. Please note that USGS does not control and cannot guarantee the relevance, timeliness, or accuracy of these outside materials.

For site security purposes and to ensure that this service remains available to all users, this government computer system employs software programs to monitor network traffic to identify unauthorized attempts to upload or change information, or otherwise cause damage. Unauthorized attempts to upload information or change information on this website are strictly prohibited and may be punishable under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act. Information may also be used for authorized law enforcement investigations. (Last modified September 21, 1999.)

U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
URL: https://volcano.si.edu/reports_weekly.cfm

 Acronyms and Abbreviations

a.s.l. - above sea level

AVO - Alaska Volcano Observatory

AVHRR - Advanced Very High Resolution Radiometer

CENAPRED - Centro Nacionale de Prevencion de Desastres (México)

CONRED - Coordinadora Nacional para la Reducción de Desastres

COSPEC - Correlation Spectrometer

CVGHM (formerly VSI) - Center of Volcanology and Geological Hazard Mitigation

CVO - Cascades Volcano Observatory (USGS)

GMS - Geostationary Meteorological Satellite

GOES - Geostationary Operational Environmental Satellite

GVO - Goma Volcano Observatory

GVP - Global Volcanism Program (Smithsonian Institution)

HVO - Hawaiian Volcano Observatory (USGS)

ICE - Instituto Costarricense de Electricidad (Costa Rica)

IG - Instituto Geofísico (Ecuador)

IGNS - Institute of Geological and Nuclear Sciences (New Zealand) - now GNS Science

INETER - Instituto Nicaragüense de Estudios Territoriales (Nicaragua)

INGEMMET - Instituto Geológical Minero y Metalúrgico (Peru)

INGEOMINAS - Instituto Colombiano de Geología y Minería (Colombia)

INGV-CT - Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania (Italy)

INSIVUMEH - Instituto Nacional de Sismologia, Vulcanologia, Meteorologia e Hidrologia (Guatemala)

IRD - Institut de Recherche pour le Développement (France)

JMA - Japanese Meteorological Agency

KEMSD - Kamchatkan Experimental and Methodical Seismilogical Department

KVERT - Kamchatkan Volcanic Eruption Response Team

M - magnitude

METEOSAT - Meteorological Satellite

MEVO - Mount Erebus Volcano Observatory

MODIS - Moderate Resolution Imaging Spectroradiometer

MVO - Montserrat Volcano Observatory

MWO - Meteorological Watch Office

NEIC - National Earthquake Information Center

NIED - National Research Institute for Earth Science and Disaster Prevention (Japan)

NOAA - National Oceanic and Atmospheric Administration

NOTAM - Notice to Airmen

OVDAS - Observatorio Volcanologico de los Andes del Sur (Chile)

OFDA - Office of US Foreign Disaster Assistance

ONEMI - Oficina Nacional de Emergencia - Ministerio del Interior (Chile)

OVPDLF - Observatoire Volcanologique du Piton de la Fournaise (France)

OVSICORI-UNA - Observatorio Vulcanologico y Sismologico de Costa Rica, Universidad Nacional (Costa Rica)

PHIVOLCS - Philippine Institute of Volcanology and Seismology (Philippines)

RSAM - Real-time Seismic Amplitude Measurement

RVO - Rabaul Volcano Observatory

SERNAGEOMIN - Servicio Nacional de Geologia y Mineria (Chile)

SIGMET - Significant Meteorological Information

SNET - Servicio Nacional de Estudios Territoriales (El Salvador)

SVERT - Sakhalin Volcanic Eruption Response Team (Russia)

USAID - US Agency for International Development

USGS - United States Geological Survey

UTC - Coordinated Universal Time

VAAC - Volcanic Ash Advisory Center

VAFTAD - Volcanic Ash Forecast Transport And Dispersion

VDAP - Volcano Disaster Assistance Program (USGS)

VHP - Volcano Hazards Program (USGS)

VRC - Volcano Research Center (Japan)

Report for Chirinkotan
SVERT and KVERT reported that moderate eruptive activity continued at Chirinkotan during 14-23 August, characterized by explosions and ash plumes that rose to 2.5-4.5 km (4,900-9,800 ft) a.s.l. and drifted as far as 125 km S, E, SE, and SW. At 1110 on 18 August an explosion produced an ash plume, 20 x 27 km in size, that rose to 2-3 km (6,600-9,800 ft) a.s.l. and drifted 7 km NE and as far as 100 km SE. An explosion at 0935 on 23 August rose to 1.5-2.5 km (4,900-8,200 ft) a.s.l. and drifted 8 km SW and later, as far as 126 km W. The Tokyo VAAC reported ash plumes to 2.7-4.9 km (9,000-16,000 ft) a.s.l. that drifted S, NE, and SW during 18 and 23 August. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Sources: Sakhalin Volcanic Eruption Response Team (SVERT), Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Fagradalsfjall
The fissure eruption in the W part of the Krýsuvík-Trölladyngja volcanic system, close to Fagradalsfjall on the Reykjanes Peninsula, continued during 18-24 August, though weather often obscured the view of the vents. During 18-19 August new lava flows were observed overflowing the SW and NE crater rims and traveling S, E, and SE in the Geldingadalur and Meradalir valleys. Gas-and-steam plumes often accompanied these flows. On 20 August a large collapse from the inner crater rim was observed in video images (Langihryggur camera), generating some ash emissions. Lava flows traveled toward the Nàtthagi valley during 21-24 August, based on webcam data. Video taken during 21-22 August showed some lava fountaining and flows overflowing the sides of the main cone, accompanied by white gas-and-steam emissions. The Aviation Color 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 also warned of gas emissions hazards.
Sources: Icelandic Meteorological Office (IMO), Icelandic National Broadcasting Service (RUV), Green Iceland Vid
Report for Fukutoku-Oka-no-Ba
The Japan Coast Guard reported that the eruption at Fukutoku-Oka-no-Ba continued during 16-22 August. Gas-and-steam emissions continued to be observed from the center of the island on 16 August. The pumice raft that was first identified on 15 August had expanded to about 100 km to the WNW and was about 13 km wide. Brown discoloration was visible surrounding the new island, which had a variable shape but a consistent diameter of 1 km by 16 August.

A local fisherman in the Ogasawara Islands who was fishing in South Iwo Jima (5 km NNE) posted photos and videos on 17, 20, and 22 August that showed strong white gas-and-steam plumes rising above the volcano. On 20 August lightning was visible within the gas-and-steam plume. On 22 August the plume was observed during 0430-0630.
Sources: Japan Coast Guard, Yutaka Kosugi
Report for Kilauea
HVO reported that a swarm of earthquakes beneath the S part of Kilauea that began at 1630 on 23 August continued into the early morning of 24 August. The earthquake swarm increased in intensity at 0130 and was accompanied by an increase in the rate of ground deformation to the W of the swarm, as recorded by the Sandhill tiltmeter. This possibly indicated that there was magma movement 1-2 km beneath the S part of the caldera. Over 140 earthquakes were recorded during 24 August, the largest of which was an Mw 3.3; a majority of them were less than Mw 1. Small earthquakes continued at a rate of at least 10 earthquakes per hour through 24 August. As a result, the Aviation Color Code and the Volcano Alert Level were raised to Orange and Watch, respectively.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Pavlof
AVO reported that occasional small explosions and elevated seismicity at Pavlof were detected in geophysical data during 18-19 August; clouds often obscured the view of the volcano. Observations from webcams and pilots indicated minor low-level ash emissions during 18-19 August. Weakly elevated surface temperatures were frequently detected during 18-22 August in the active vent based on satellite and webcam data. The Volcano Alert Level and Aviation Color Code remained at Watch and Orange, respectively.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Whakaari/White Island
GeoNet maintained the Volcanic Alert Level at 2 and the Aviation Color Code at Yellow for Whakaari/White Island. A volcanic earthquake was recorded at 1900 on 19 August that continued for ten minutes; other seismic activity has been minor. Webcam images showed some incandescence during the night, which suggested that temperatures in the vent area were likely 500-600°C. On 22 August at 0740 a period of minor ash emissions was observed from the active vent area that lasted for two minutes, based on webcam images. Low levels of ground deformation around the active vent and lake area were identified in satellite radar data.
Source: GeoNet
Report for Atka Volcanic Complex
AVO reported that small earthquakes and seismic tremors at Atka continued to be detected, though at near background levels during 18-24 August. The Aviation Color Code remained at Yellow and the Volcano Alert Level at Advisory.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Ebeko
According to volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, and the Tokyo VAAC, explosions continued during 14-20 August and produced ash plumes that rose as high as 3 km (10,000 ft) a.s.l and drifted S, SE, E, and NE. Thermal anomalies were detected in satellite imagery on 13 and 14 August. On 25 August an explosion produced an ash plume that rose to 3.7 km (12,000 ft) a.s.l. and drifted 10 km SE. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Fuego
INSIVUMEH reported that 6-13 explosions per hour were recorded during 18-25 August at Fuego, though the weather sometimes prevented visual confirmation. The resulting ash plumes rose to 4.5-4.8 km (14,800-15,700 ft) a.s.l. and drifted as far as 15 km W, SW, S, and NW, causing daily ashfall downwind in Panimaché I and II (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), Yucales (12 km SW), El Porvenir (8 km ENE), and Yepocapa (8 km NW). White gas-and-steam plumes rose to 4.5 km (14,764 ft) a.s.l. on 19 and 25 August. Shock waves often rattled buildings around the volcano as far as 15 km from the summit. Block avalanches accompanied the explosions, descending the Santa Teresa, Ceniza (SSW), Taniluyá (SW), Trinidad (S), Seca (W), Las Lajas (SE), and Honda drainages, sometimes reaching vegetated areas. Incandescent ejecta was visible rising 100-400 m above the summit during the nights and early mornings of 20-23 August.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Great Sitkin
AVO reported that the lava dome at Great Sitkin remained active during 17-24 August; satellite imagery showed changes from a diameter of 800 m on 17 August to 850-860 m throughout 18-21 August. Elevated surface temperatures and daily small earthquakes were consistent with an active dome. Gas-and-steam plumes were visible to local ground observers and in satellite imagery during 20-22 and 24 August. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Ibu
PVMBG reported that during 18-24 August gray-and-white ash plumes from Ibu rose 200-800 m above the summit and drifted N, W, and NW. On 18 August at 0810 an ash plume rose 800 m above the summit and drifted W. A thermal anomaly was visible in satellite images during 22-23 August, according to the Darwin VAAC. The Alert Level remained at a 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater and 3.5 km away on the N side.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Kadovar
Based on satellite and wind model data, the Darwin VAAC reported that on 19 August an ash plume from Kadovar rose to an altitude of 1.2 km (4,000 ft) a.s.l. and drifted NW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Karymsky
KVERT reported that ash emissions from Karymsky were observed in satellite data during 14-20 August; gas-and-steam plumes containing some ash were also noted. The Tokyo VAAC reported that multiple ash plumes rose to 2.4-3.4 km (8,000-11,000 ft) a.s.l. and drifted SE, SW, S, and E during 17-21 August. On 19 August an explosion produced an ash plume that rose 2-2.5 km (6,600-8,200 ft) a.s.l and drifted 60 km ESE. Ash plumes during 19-20 August rose to 2.4 km (8,000 ft) a.s.l. and drifted E. A thermal anomaly was identified in satellite imagery all week. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Langila
Based on analyses of satellite imagery and wind model data, the Darwin VAAC reported that on 20 August ash plumes from Langila rose to 2.4 km (8,000 ft) a.s.l. and drifted WNW. A thermal anomaly was observed at the summit based on satellite imagery on 20 August.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Lewotolok
PVMBG reported that daily white, gray, and sometimes black plumes from Lewotolok rose 50-1,500 m above the summit and drifted SW, NW, and W during 18-24 August. Eruptive activity on 18 and 22 August generated an ash plume that rose 1 and 1.5 km above the summit, respectively, both of which drifted W. Material was ejected as far as 500 m SE on 18 August. On 22 August at 1244 an ash plume was reported 1.5 km above the summit and drifted generally W. 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.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Merapi
BPPTKG reported that both the lava dome just below Merapi’s SW rim and the lava dome in the summit crater remained active during 13-19 August. Webcam images showed some changes in the SW dome due to lava avalanches and pyroclastic flows; there were no significant changes in the central dome. The volume of the SW lava dome was 1.35 million cubic meters. During 13-19 August a total of 20 pyroclastic flows were observed descending the SW flank as far as 3.5 km. Lava avalanches were observed 172 times to the SW, traveling up to 2 km. BNPB noted that ashfall was reported in several areas on 16 August, including Dukun, Sawangan, Tegalrejo, Secang, Gowok, Mertoyudan, Selo, Mojotengah, Temanggung, Kedu, Pringsurat, Bulu, Tlogomulyo, Kranggan, and Parakan.

PVMBG reported that during 18-19 and 23-24 August white plumes rose 20-200 m above the crater and drifted in different directions. As many as 331 lava avalanches traveled a maximum distance of 1.5 km SW. Two pyroclastic flows moved as far as 2 km, though the direction was not observed. The Alert Level remained at a 3 (on a scale of 1-4), and the public was warned to stay 5 km away from the summit.
Sources: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG), Badan Nacional Penanggulangan Bencana (BNPB), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Pacaya
INSIVUMEH reported that white-to-blue gas-and-steam emissions rose as high as 600 m above Pacaya’s Mackenney crater and drifted as far as 2 km S, SW, and N during 18-25 August. Seismic stations recorded some weak explosion and degassing events on 18 August.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Reventador
IG reported that several ash emissions from Reventador during 18-24 August rose 500-1,400 m above the summit and drifted NW, W, SW, and S; sometimes weather conditions prevented visual confirmation. Seismicity was characterized by daily explosions, harmonic tremor, long-period earthquakes, and signals that indicated emissions. The Washington VAAC reported gas-and-steam and ash plumes to 1.4 km above the summit that drifted W, NW, and SW, often observed multiple times per day in satellite imagery or webcams. Nighttime crater incandescence was frequently observed, accompanied by incandescent blocks rolling down the NE, E, and S flanks as far as 600 m. A lava flow was reported traveling down the NE flank during 17-18 August.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Washington Volcanic Ash Advisory Center (VAAC)
Report for Sangay
IG reported gas-and-ash emissions from Sangay rising 500-1,500 m above the summit that drifted W and SW during 19-20 and 24 August. During 20-23 August gas-and-steam plume rose 1-2 km above the summit and drifted W, SW, and NW. Weather clouds and rain sometimes prevented visual and webcam observations of the volcano. Ash plumes were identified in satellite images by the Washington VAAC, rising 570-1,500 m above the volcano and drifting W and SW during 19-21 and 23-24 August. During the evening on 19 August explosions accompanied by incandescent blocks were reported around 1852 rolling down the SE drainage. Signals indicating lahars were recorded by the seismic network during 18-19 and 22-23 August.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Washington Volcanic Ash Advisory Center (VAAC)
Report for Santa Maria
INSIVUMEH reported that daily ash plumes from Santa Maria’s Santiaguito lava-dome complex during 18-25 August rose to 2.8-3.5 km (9,200-11,500 ft) a.s.l. and drifted as far as 8 km W and SW. Ashfall was reported in San Marcos (8 km SW), Loma Linda Palajunoj (6 km WSW), and surrounding farms on 24 August. An active lava flow 600 m long extended down the W and S flanks of the dome during 18-24 August. Collapses of blocky lava from the Caliente dome generated block-and-ash avalanches down the W, S, and SW flanks, often reaching the base and causing minor ashfall on the flanks. Weak explosions accompanied these avalanches on 21 August and generated abundant gas-and-steam emissions. Nighttime incandescence was often observed from the lava flow and dome.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Semeru
PVMBG reported that a vertical gray-and-white plume from Semeru rose 400-500 m above the summit and drifted SW on 19 August. This eruption continued during 20-24 August, but the height of the plume was not observed due to cloud cover. 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.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Semisopochnoi
AVO reported that multiple explosions and seismicity at Semisopochnoi's North Cerberus crater continued during 18-24 August. Low-level gas-and-ash emissions, including occasional sulfur dioxide emissions were detected in satellite and webcam data during 18-24 August and rose no higher than 3 km (10,000 ft) a.s.l.; views were often obscured due to weather. On 20 August minor ashfall deposits were reported; ashfall may have continued following explosive events during the rest of the week. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Sheveluch
KVERT reported that the growth of the lava dome at Sheveluch continued during 14-24 August, accompanied by strong fumarolic activity, dome incandescence, and hot avalanches. A thermal anomaly was identified in satellite imagery all week. Gas-and-steam plumes containing some ash drifted 370 km SW, E, and SE. On 21 and 24 August ash plumes rose to 4 km (13,100 ft) a.s.l. and drifted 86 km SE and 3.5 km (11,500 ft) a.s.l. and drifted as far as 100 km SE, respectively. The Tokyo VAAC reported ash plumes during 17-25 August that rose to 3.7-5.5 km (12,000-18,000 ft) a.s.l. and drifted E, S, SE. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Suwanosejima
JMA reported that explosions at Suwanosejima's Ontake crater were detected on 19, 20, and 21 August. The first explosion at 0137 on 19 August produced an ash plume that rose 3 km above the crater and drifted NE, followed by another at 1613 that generated an ash plume 2.2 km above the crater and drifted N. A small amount of ashfall was reported in Yakushima, Nishinoomote, and Nakatane. A third explosion at 2059 that day produced an ash plume that rose 2.5 km above the crater and drifted N; ashfall was reported in Toshima village (4 km SSW). Explosions at 0628 and 0713 on 20 August generated ash plumes that rose 2.5-3 km above the crater and drifted N, resulting in ashfall in Toshima village, with smaller amounts of ash in Yakushima, Mishima, Ibusuki, Minamikyushu, and Makurazaki. On 21 August at 0617 an explosion generated an ash plume that rose 3.2 km above the crater and drifted N. A large amount of ashfall (over 1 mm) was reported in Toshima village and smaller amounts (less than 0.1 mm) were reported in Makurazaki, Minamisatsuma, Minamikyushu, Kagoshima, Ibusuki, and Hioki. A second explosion followed at 0906 that produced an ash plume 3.2 km above the crater that drifted N. The Tokyo VAAC reported ash plumes to 1.5-3.9 km (5,000-13,000 ft) altitude that drifted NE during 18-25 August. The Alert Level remained at 2 and the public was warned to stay 1 km away from the crater.
Sources: Japan Meteorological Agency (JMA), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Taal
PHIVOLCS reported that gas-and-steam plumes from Taal rose 1-3 km and sulfur dioxide emissions peaked at 15,347 tonnes/day on 19 August and declined to an average of 8,351 tonnes/day during 13-19 August. The Volcano Alert Level remained at a 2 (on a scale of 0-5). PHIVOLCS reminded the public that the entire Taal Volcano Island is a Permanent Danger Zone (PDZ).
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Tengger Caldera
PVMBG reported that during 18-24 August white gas-and-steam plumes rose 50-400 m above Tengger Caldera’s Bromo cone and drifted SW, W, and NW. A weak thermal anomaly was visible in Sentinel-2 infrared satellite images on 23 August. The Alert Level remained at 2 (on a scale of 1-4), and visitors were warned to stay outside of a 1-km radius of the crater.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Sentinel Hub