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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 20 August-26 August 2008
Name Location Eruption Start Date Report Status
Kasatochi Andreanof Islands (USA) New
Kirishimayama Kyushu (Japan) New
Soufriere Hills Montserrat New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Batu Tara Komba Island Continuing
Bezymianny Central Kamchatka (Russia) 2016 Dec 5 Continuing
Chaiten Southern Chile Continuing
Chikurachki Paramushir Island (Russia) Continuing
Cleveland Chuginadak Island (USA) Continuing
Dukono Halmahera 1933 Aug 13 Continuing
Fuego South-Central Guatemala 2002 Jan 4 Continuing
Karymsky Eastern Kamchatka (Russia) Continuing
Kilauea Hawaiian Islands (USA) 2021 Sep 29 Continuing
Llaima Central Chile Continuing
Okmok Fox Islands (USA) Continuing
Pacaya South-Central Guatemala Continuing
Rabaul New Britain (Papua New Guinea) Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
Semeru Eastern Java 2014 Apr 1 ± 15 days Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 Continuing
Tungurahua Ecuador Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 18,613 individual reports over 1,152 weeks (average of 16 per week) on 329 different volcanoes.

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Agung Cotopaxi Iliamna Lewotolok Pinatubo St. Helens
Ahyi Cuicocha Iliwerung Little Sitkin Planchon-Peteroa Stromboli
Aira Cumbal Inielika Llaima Poas Sulu Range
Akan Dabbahu Ioto Lokon-Empung Popocatepetl Sumbing
Alaid Davidof Irazu Lonquimay Purace Sundoro
Alu-Dalafilla Dempo Iya Lopevi Puyehue-Cordon Caulle Suretamatai
Ambae Descabezado Grande Izu-Torishima Machin Rabaul Suwanosejima
Ambang Dieng Volcanic Complex Jackson Segment Makushin Raikoke Taal
Ambrym Dukono Kaba Maly Semyachik Ranakah Tair, Jebel at
Anatahan Ebeko Kadovar Manam Raoul Island Takawangha
Aniakchak Ebulobo Kaitoku Seamount Manda Hararo Rasshua Talang
Antillanca Volcanic Complex Edgecumbe Kama'ehuakanaloa Marapi Raung Tambora
Antuco Egon Kambalny Maroa Redoubt Tanaga
Apoyeque Ekarma Kanaga Martin Reventador Tandikat-Singgalang
Arenal Epi Kanlaon Masaya Reykjanes Tangkoko-Duasudara
Asamayama Erebus Karangetang Maule, Laguna del Rincon de la Vieja Tangkuban Parahu
Askja Erta Ale Karkar Mauna Loa Rinjani Tara, Batu
Asosan Etna Karthala Mayon Ritter Island Ta'u
Atka Volcanic Complex Etorofu-Yakeyama [Grozny Group] Karymsky McDonald Islands Rotorua Taupo
Augustine Eyjafjallajokull Kasatochi Melimoyu Ruang Telica
Avachinsky Fagradalsfjall Katla Merapi Ruapehu Tenerife
Awu Fernandina Katmai Midagahara Ruiz, Nevado del Tengger Caldera
Axial Seamount Fogo Kavachi Misti, El Sabancaya Three Sisters
Azul, Cerro Fonualei Kelimutu Miyakejima Sakar Tinakula
Azumayama Fournaise, Piton de la Kelud Momotombo Salak Tofua
Bagana Fourpeaked Kerinci Monowai San Cristobal Tokachidake
Balbi Fuego Ketoi Montagu Island San Miguel Tolbachik
Bamus Fujisan Kharimkotan Moyorodake [Medvezhia] San Vicente Toliman
Banda Api Fukutoku-Oka-no-Ba Kick 'em Jenny Mutnovsky Sangay Tongariro
Bardarbunga Galeras Kie Besi Myojinsho Sangeang Api Trident
Barren Island Galunggung Kikai Nabro Santa Ana Tungurahua
Batur Gamalama Kilauea Negra, Sierra Santa Maria Turrialba
Bezymianny Gamkonora Kirishimayama Negro, Cerro Sao Jorge Ubinas
Bogoslof Gareloi Kita-Ioto Nightingale Island Sarigan Ugashik-Peulik
Brava Gaua Kizimen Nishinoshima Sarychev Peak Ukinrek Maars
Bristol Island Gorely Klyuchevskoy Nisyros Saunders Ulawun
Bulusan Great Sitkin Kolokol Group Novarupta Savo Unnamed
Calbuco Grimsvotn Koryaksky NW Rota-1 Semeru Unnamed
Callaqui Guagua Pichincha Krakatau Nyamulagira Semisopochnoi Veniaminof
Cameroon Guallatiri Krummel-Garbuna-Welcker Nyiragongo Seulawah Agam Villarrica
Campi Flegrei del Mar di Sicilia Guntur Krysuvik-Trolladyngja Ofu-Olosega Sheveluch Vulcano
Cayambe Hachijojima Kuchinoerabujima Okataina Shishaldin West Mata
Chachadake [Tiatia] Hakoneyama Kurikomayama Okmok Simbo Westdahl
Chaiten Heard Kusatsu-Shiranesan Ontakesan Sinabung Whakaari/White Island
Chiginagak Hekla Kverkfjoll Oraefajokull Sinarka Witori
Chikurachki Helgrindur La Palma Osorno Siple Wolf
Chiles-Cerro Negro Hierro Lamington Pacaya Sirung Yakedake
Chillan, Nevados de Hokkaido-Komagatake Lamongan Pagan Slamet Yasur
Chirinkotan Home Reef Langila Palena Volcanic Group Snaefellsjokull Yufu-Tsurumi
Chirpoi Hood Lanin Paluweh Soputan Zaozan [Zaosan]
Ciremai Huaynaputina Lascar Panarea Sorikmarapi Zavodovski
Cleveland Hudson, Cerro Late Papandayan Sotara Zhupanovsky
Colima Huila, Nevado del Lateiki Parker Soufriere Hills Zubair Group
Colo Hunga Tonga-Hunga Ha'apai Lengai, Ol Doinyo Pavlof Soufriere St. Vincent
Concepcion Ibu Leroboleng Pelee South Sarigan Seamount
Copahue Ijen Lewotobi Peuet Sague Spurr
 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 Kasatochi
AVO reported that during 20-26 August seismic activity from Kasatochi was detected by stations on Great Sitkin, approximately 40 km W. Clouds prevented satellite image observations. Active fumaroles and hot pyroclastic flow deposits over much of the volcano were observed on 22 August by a visiting scientist. On 23 August, the smell of sulfur was reported in the town of Adak. The Volcano Alert Level remained at Watch and the Aviation Color Code at Orange.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Kirishimayama
Based on reports from JMA, the Tokyo VAAC reported a possible eruption of Kirishima on 22 August. The altitude and direction of a possible resultant plume were not reported.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Soufriere Hills
MVO reported that during 15-22 August, evidence suggested that the W side of the Soufrière Hills lava dome continued to grow. Cloud cover prevented visual observations. Rockfalls and long-period seismicity increased. Most of the rockfalls occurred on the W side of the lava dome in a new channel that developed below Gages Wall. Ash plumes occasionally generated by the rockfalls were most noticeable on 16 and 17 August. On 19 August a pyroclastic flow descended the Tar River Valley. According to news reports, on 25 August a rainfall-induced pyroclastic flow occurred on the W flank, split into two parts, and caused ashfall and a strong scent of gases in areas N. The event enlarged and steepened the rockfall gully below Gages Wall. The Hazard Level remained at 3.
Sources: Montserrat Volcano Observatory (MVO), Caribbean Net News
Report for Aira
Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 23 August. The altitude and direction of a possible resultant plume were not reported.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Batu Tara
Scientists on a boat passing Batu Tara about 24 km to the N observed six distinct eruptions of ash plumes from the westernmost area of the summit crater during a 45-minute period on 25 August. The plumes rose to an estimated altitude of 1.1-1.5 km (3,600-5,000 ft) a.s.l. and drifted W.
Source: Tristram Burley, personal communication
Report for Bezymianny
KVERT reported that seismic activity at Bezymianny was slightly above background levels during 14 and 16-18 August and at background levels during 15 and 20-21 August. Analysis of satellite imagery revealed a thermal anomaly over the lava dome during 14-15 and 18-21 August. The thermal anomaly enlarged just before an explosion on 19 August. The explosion produced an ash plume that rose to an altitude of 9 km (29,500 ft) a.s.l. and drifted 1,200 km W. Staff at a seismic station about 50 km W reported ashfall and the smell of volcanic gas. The Level of Concern Color Code was lowered to Yellow.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Chaiten
Based on web camera views, pilot observations, and analysis of satellite imagery, the Buenos Aires VAAC reported that during 20-23 and 26 August ash plumes from Chaitén rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted SE, E, and NE. A thermal anomaly over the lava dome was detected on satellite imagery during 22-23 August.
Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Report for Chikurachki
KVERT reported that clouds prevented satellite image views of Chikurachki during 15-22 August. The level of seismicity was unknown because Chikurachki lacks dedicated seismic instruments. The Level of Concern Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Cleveland
AVO reported that cloud cover prevented satellite observations of Cleveland during 20-26 August, although a possible thermal anomaly was present on 24 August. On 25 August the Volcano Alert Level was lowered to Advisory and the Aviation Color Code to Yellow.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Dukono
Based on analysis of satellite imagery, the Darwin VAAC reported that on 24 August an ash plume from Dukono rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted NW. On 26 August, ash plumes rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted W and WNW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Fuego
INSIVUMEH reported that on 20 August lahars descended several rivers to the S and SE of Fuego, carrying fine material as well as blocks up to 1 m in diameter. Strong currents in Río Cenizas and El Jute were noted. During 25-26 August, explosions produced ash plumes that rose to an altitude of 4.1 km (13,500 ft) a.s.l. and drifted SW. Fumarolic plumes rose to an altitude of 4 km (13,100 ft) a.s.l. and also drifted SW. A 300-m-long lava flow traveled W towards the Santa Teresa ravine.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Karymsky
KVERT reported that seismic activity at Karymsky was at typical levels during 14-15, 17, and 19-20 August. They also reported possible explosions during 14-15 and 17-20 August. Volcanic tremor was detected on 14 and 20 August. The Level of Concern Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kilauea
HVO reported that during 20-26 August, lava flowed SE through a lava tube system from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex to the Waikupanaha ocean entry. On 20 August, geologists observed bursting lava bubbles from an area E of Waikupanaha that threw molten fragments 10-20 m into the air. The sulfur dioxide emission rate at Pu'u 'O'o was 3,200 and 1,800 tonnes per day on 20 and 22 August, respectively; the average background rate is about 2,000 tonnes per day.

Kilauea earthquakes were centered in various locations along the Koa'e fault system, S and W of the caldera, beneath the summit, along the S-flank faults, and along the E and SW rift zones. Beneath Halema'uma'u crater, more than 40 small earthquakes per day (background 40) also occurred but were too small to be located more precisely. About 100 earthquakes were detected on 26 August. The vent in Halema'uma'u crater continued to produce a predominantly white plume with minor ash content that drifted mainly SW. The plume was occasionally tinged brown. Weak night-time incandescence was intermittently seen at the base of the plume, and rock impacts and muted rushing sounds were heard in the vicinity of the crater. On 21 August, an earthquake was accompanied by a 400-m-high jet of mostly gas that rose vertically, then drifted SW. The jet also contained some rock dust and bits of volcanic glass. Several small ash ejections occurred on 25 August. The sulfur dioxide emission rate was 600-1,000 tonnes per day during 20-25 August. The pre-2008 background rate was 150-200 tonnes per day.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Llaima
SERNAGEOMIN reported that steam plumes from the pyroclastic cones in Llaima's main crater were visible during periods of clear weather on 16 August. Steam plumes rose from the W flank where lava flows were active in February and July. On 17 August, sporadic gas-and-ash emissions were observed. Cloud cover prevented observations during 18-20 August. On 21 August, three explosions produced ash plumes that rose to an altitude of 3.6 km (11,800 ft) a.s.l. and drifted E. Gas and steam was emitted in between explosions; resultant plumes rose to an altitude of 3.4 km (11,200 ft) a.s.l. and drifted 9 km E. During an overflight, scientists observed steam-and-gas plumes being emitted from a small crater in the N sector of the main crater. A larger crater, about 100 m in diameter, in the central sector emitted ash. The ash plumes rose to an altitude of 3.4 km (11,200 ft) a.s.l. and drifted E. A thin layer of ash blanketed the E flank. Ash-and-gas plumes from the main crater drifted W on 22 August. On 23 August, observers reported that incandescent material was ejected less than 1 km above the crater. The next day, an ash plume drifted about 1.5 km SSE. Ash blanketed some areas of the flanks. The Volcano Alert Level remained at Yellow.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
Report for Okmok
AVO reported that seismic activity at Okmok decreased on 19 August to near pre-eruption levels and remained low during 20-24 August. Occasional bursts of volcanic tremor were detected. Although satellite views were hindered due to cloud cover, a possible thermal anomaly in the crater was present on 21, 24, and 25 August. The Volcano Alert Level remained at Watch and the Aviation Color Code at Orange.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Pacaya
INSIVUMEH reported that during 21-26 August, fumarolic plumes from Pacaya's MacKenney cone rose to an altitude of 3.2 km (10,500 ft) a.s.l. and drifted W and SW. Incandescence from the crater was occasionally seen at night. Lava flows on the SW flank branched and traveled a maximum of 300 m; lava continued to fill in the area between MacKenney cone and Cerro Chino crater to the N. Avalanches occurred from the lava-flow fronts on 26 August.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Rabaul
RVO reported that ash plumes from Rabaul caldera's Tavurvur cone continued to be emitted during 18-22 August, although less so than during 16-18 August. Some prolonged ash-free intervals were immediately followed by explosions that produced ash plumes. The plumes drifted NW and caused ashfall in areas downwind. Occasionally incandescence at the summit was observed and roaring noises were heard. Explosions also ejected incandescent lava fragments.

Based on analysis of satellite imagery, the Darwin VAAC reported that on 23 August ash plumes rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted NW.
Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Rabaul Volcano Observatory (RVO)
Report for Santa Maria
INSIVUMEH reported that during 21-26 August explosions from Caliente, a unit of Santa María's Santiaguito lava dome complex, produced ash plumes that rose to altitudes of 2.8-3.3 km (9,200-10,800 ft) a.s.l. and drifted S, SW, and W. Constant degassing was noted.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Semeru
Based on pilot reports and observations of satellite imagery, the Darwin VAAC reported that during 21-22 August ash plumes from Semeru rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted W.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Sheveluch
KVERT reported that seismic activity at Shiveluch was slightly above background levels during 15-22 August. Analysis of satellite imagery revealed a thermal anomaly on the lava dome on 15, 18, and 21 August. The Level of Concern Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Suwanosejima
Based on reports from JMA, the Tokyo VAAC reported explosions from Suwanose-jima during 24-26 August. Resultant plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. during 25-26 August.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Tungurahua
The IG reported that on 19 August fumarolic plumes from Tungurahua rose 20 m above the NE crater and on 20 August, steam-and-ash plumes rose about 50 m above the crater. On 21 August, intense rains prompted the Tungurahua Observatory (OVT) to issue a warning of potential lahars in the Vascún river. A natural dam in the river was previously identified as potentially hazardous. On 23 August, a person in El Salado detected vibrations. The dam ruptured and material descended the Vascún river to the N at speeds of 10-15 m/s, destroying a house, damaging and demolishing bridges, and destroying multiple public swimming pools in the Baños area. Two people were injured and two people were missing.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)