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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 15 May-21 May 2024
Name Country Volcanic Province Eruption Start Date Report Status
Asosan Japan Nankai Volcanic Arc New
Concepcion Nicaragua Central America Volcanic Arc New
Ibu Indonesia Halmahera Volcanic Arc 2008 Apr 5 New
Marapi Indonesia Sunda Volcanic Arc 2023 Dec 3 New
Purace Colombia Andean Northern Volcanic Arc New
Ruang Indonesia Sangihe Volcanic Arc 2024 Apr 16 New
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 New
Slamet Indonesia Sunda Volcanic Arc New
Spurr United States Alaska Peninsula Volcanic Arc New
Taal Philippines Taiwan-Luzon Volcanic Arc 2024 Apr 12 New
Ubinas Peru Andean Central Volcanic Arc 2024 May 6 New
Aira Japan Ryukyu Volcanic Arc 2017 Mar 25 Continuing
Campi Flegrei Italy Italian Peninsula Volcanic Provinces Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Ebeko Russia Kuril Volcanic Arc 2022 Jun 11 Continuing
Fernandina Ecuador Galapagos Hotspot Volcano Group Continuing
Great Sitkin United States Aleutian Ridge Volcanic Arc 2021 May 25 Continuing
Lewotobi Indonesia Sunda Volcanic Arc 2023 Dec 23 Continuing
Lewotolok Indonesia Sunda Volcanic Arc 2020 Nov 27 Continuing
Merapi Indonesia Sunda Volcanic Arc 2020 Dec 31 Continuing
Popocatepetl Mexico Trans-Mexican Volcanic Belt 2005 Jan 9 Continuing
Reventador Ecuador Andean Northern Volcanic Arc 2008 Jul 27 Continuing
Sangay Ecuador Andean Northern Volcanic Arc 2019 Mar 26 Continuing
Semeru Indonesia Sunda Volcanic Arc 2017 Jun 6 Continuing
Stromboli Italy Aeolian Volcanic Arc 1934 Feb 2 Continuing
Suwanosejima Japan Ryukyu Volcanic Arc 2004 Oct 23 Continuing
Villarrica Chile Andean Southern Volcanic Arc 2014 Dec 2 ± 7 days Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,299 individual reports over 1,228 weeks (average of 17 per week) on 335 different volcanoes.

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Agung Cotopaxi Iliamna Little Sitkin Planchon-Peteroa Stromboli
Ahyi Cuicocha Iliwerung Llaima Poas Sulu Range
Aira Cumbal Inielika Lokon-Empung Popocatepetl Sumbing
Akan Dabbahu Ioto Lonquimay Purace Sundoro
Alaid Davidof Irazu Lopevi Puyehue-Cordon Caulle Suoh
Alu-Dalafilla Dempo Iya Machin Rabaul Suretamatai
Ambae Descabezado Grande Izu-Torishima Makushin Raikoke Suwanosejima
Ambang Dieng Volcanic Complex Jackson Segment Maly Semyachik Ranakah Taal
Ambrym Dukono Kaba Manam Raoul Island Tair, Jebel at
Anatahan East Epi Kadovar Manda Hararo Rasshua Takawangha
Aniakchak Ebeko Kaitoku Seamount Marapi Raung Talang
Antillanca Volcanic Complex Ebulobo Kama'ehuakanaloa Maroa Redoubt Tambora
Antuco Edgecumbe Kambalny Martin Reventador Tanaga
Apoyeque Egon Kanaga Masaya Reykjanes Tandikat-Singgalang
Arenal Ekarma Kanlaon Matthew Island Rincon de la Vieja Tangkoko-Duasudara
Asamayama Eldey Karangetang Maule, Laguna del Rinjani Tangkuban Parahu
Askja Erebus Karkar Mauna Loa Ritter Island Tara, Batu
Asosan Erta Ale Karthala Mayon Rotorua Ta'u
Atka Volcanic Complex Etna Karymsky McDonald Islands Ruang Taupo
Augustine Etorofu-Yakeyama [Grozny Group] Kasatochi Melebingoy Ruapehu Telica
Avachinsky Eyjafjallajokull Katla Melimoyu Ruby Tenerife
Awu Fagradalsfjall Katmai Merapi Ruiz, Nevado del Tengger Caldera
Axial Seamount Fernandina Kavachi Midagahara Sabancaya Three Sisters
Azul, Cerro Fogo Kelimutu Misti, El Sakar Tinakula
Azumayama Fonualei Kelud Miyakejima Salak Tofua
Bagana Fournaise, Piton de la Kerinci Momotombo San Cristobal Tokachidake
Balbi Fourpeaked Ketoi Monowai San Miguel Tolbachik
Bamus Fuego Kharimkotan Montagu Island San Vicente Toliman
Banda Api Fujisan Kick 'em Jenny Moyorodake [Medvezhia] Sangay Tongariro
Bardarbunga Fukutoku-Oka-no-Ba Kie Besi Mutnovsky Sangeang Api Trident
Barren Island Galeras Kikai Myojinsho Santa Ana Tungurahua
Batur Galunggung Kilauea Nabro Santa Maria Turrialba
Bezymianny Gamalama Kirishimayama Negra, Sierra Sao Jorge Ubinas
Bogoslof Gamkonora Kita-Ioto Negro, Cerro Sarigan Ugashik-Peulik
Brava Gareloi Kizimen Nightingale Island Sarychev Peak Ukinrek Maars
Bristol Island Gaua Klyuchevskoy Nishinoshima Saunders Ulawun
Bulusan Gorely Kolokol Group Nisyros Savo Unnamed
Calbuco Great Sitkin Koryaksky Novarupta Semeru Unnamed
Callaqui Grimsvotn Krakatau NW Rota-1 Semisopochnoi Veniaminof
Cameroon Guagua Pichincha Krummel-Garbuna-Welcker Nyamulagira Seulawah Agam Villarrica
Campi Flegrei Guallatiri Krysuvik-Trolladyngja Nyiragongo Sheveluch Vulcano
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Ofu-Olosega Shishaldin West Mata
Cayambe Hachijojima Kurikomayama Okataina Simbo Westdahl
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Okmok Sinabung Whakaari/White Island
Chaiten Heard Kverkfjoll Ontakesan Sinarka Witori
Chiginagak Hekla La Palma Oraefajokull Siple Wolf
Chikurachki Helgrindur Lamington Osorno Sirung Wrangell
Chiles-Cerro Negro Hierro Lamongan Pacaya Slamet Yakedake
Chillan, Nevados de Hokkaido-Komagatake Langila Pagan Snaefellsjokull Yasur
Chirinkotan Home Reef Lanin Palena Volcanic Group Soputan Yufu-Tsurumi
Chirpoi Hood Lascar Paluweh Sorikmarapi Zaozan [Zaosan]
Ciremai Huaynaputina Late Panarea Sotara Zavodovski
Cleveland Hudson, Cerro Lateiki Papandayan Soufriere Hills Zhupanovsky
Colima Huila, Nevado del Lengai, Ol Doinyo Pavlof Soufriere St. Vincent Zubair Group
Colo Hunga Tonga-Hunga Ha'apai Leroboleng Pelee South Sarigan Seamount
Concepcion Ibu Lewotobi Peuet Sague Spurr
Copahue Ijen Lewotolok Pinatubo St. Helens
 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 Asosan
JMA reported continuing unrest at Asosan. Sulfur dioxide gas emissions were somewhat high, averaging 1,600 tons per day (t/d), when measured during a field survey on 9 May. The amplitude of volcanic tremors began to increase at around 0600 on 15 May and increased again round 0900. At 0920 the Alert Level was raised to 2 (on a scale of 1-5) and the public was warned to stay at least 1 km away from the crater. During a field visit later that morning scientists observed a hot spring within the pool on the Nakadake Crater floor and measured sulfur dioxide emissions of 800 t/d. Volcanic tremor amplitude was variable and decreased to low levels by 0700 on 16 May. White steam-and-gas plumes rose 100-300 m above the crater rim during 16-17 May and crater incandescence was occasionally visible in webcam images at night. Sulfur dioxide emissions had decreased to 500 t/d on 17 May.
Source: Japan Meteorological Agency (JMA)
Report for Concepcion
Instituto Nicaragüense de Estudios Territoriales (INETER) reported that a small-to-moderate explosion at Concepción occurred at 1420 on 16 May. An ash-and-gas plume rose at least 2 km above the crater rim and caused ashfall up to 1 mm deep in Los Ramos (SE), La Unión (SE), Los Angeles, La Flor (5 km NW), Urbaite, and Las Pilas. According to the Washington VAAC the ash plume was identified in satellite images at 1520 drifting NW at an altitude of about 5.5 km (18,000 ft) a.s.l., or at around 3.8 km above the summit.
Sources: Instituto Nicaragüense de Estudios Territoriales (INETER), Washington Volcanic Ash Advisory Center (VAAC)
Report for Ibu
PVMBG reported that the eruption at Ibu continued to intensify during 11-21 May, with ash plumes rising higher and having denser ash content. Seismicity was also high and increasing. Beginning on 11 May the ash plumes began rising 4-5 km above the summit; the plumes were dense and gray and drifted N and NW, and incandescent ejecta was visible. Eruptive events were recorded on 12 and 14 May, though weather conditions prevented visual observations. During 13-16 May gray-to-black ash plumes rose as high as 5 km and drifted multiple directions. Roaring and banging noises were heard in areas as far away as the Ibu observation post (9 km W). At 1500 on 16 May the Alert Level was raised to 4 (the highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 7 km away from the N crater wall opening. BNPB reported that 263 residents evacuated from three villages, Gam Ici, Goin, and Sangaji Nyeku.

White-and-gray ash plumes with variable densities rose 4-5 km above the summit and drifted multiple directions during 17-18 and 20-21 May. Photos from just after 2000 on 18 May showed lightning in the dense ash plumes. Only white steam-and-gas plumes were visible on 19 May, rising 200-300 m above the summit and drifting N, NE, and E. According to a news report the total number of evacuees rose to more than 400 by 19 May; the residents were from seven villages in the West Halmahera District.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Badan Nacional Penanggulangan Bencana (BNPB), Antara News
Report for Marapi
PVMBG reported that eruptive activity at Marapi (on Sumatra) was ongoing during 15-21 May. White gas-and-steam plumes rose 200-300 m above the summit and drifted in multiple directions on most days; no emissions were visible on 16 and 20 May. White-and-gray ash plumes rose 400-550 above the summit and drifted NW on 18 May.

The 11 May lahars that caused several fatalities, evacuations, and widespread damage in the Agam Regency continued to impact the area. As of 1700 on 16 May BNBP reported that the death toll had reached 67 people, while 20 remained missing and 40-44 had been injured; overall 989 families were impacted by the lahars. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 4.5 km away from the active crater.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Badan Nacional Penanggulangan Bencana (BNPB)
Report for Purace
Observatorio Vulcanológico y Sismológico de Popayán, Servicio Geologico Colombiano (SGC) reported that the daily number of both volcanic tremor (VT) and long-period (LP) seismic events at Puracé trended downward during 14-21 May, and by the end of the week had reached pre-29 April levels. The VT events had low magnitudes and were located at depths up to 2.4 km beneath the volcano and its E flank. The largest VT events, M 1.5, were recorded at 1821 on 14 May and at 0711 on 16 May. LP earthquakes were located at depths less than 3 km beneath the volcano and its N flank. Inclement weather often prevented visual observations of emissions, though during 15-16 May a gas plume rose as high as 650 m above the summit and drifted W. Both carbon dioxide and sulfur dioxide emissions remained above baseline levels. The Alert Level remained at Orange (the second highest level on a four-color scale).
Source: Servicio Geológico Colombiano (SGC)
Report for Ruang
On 15 May BNPB reported that a total of 9,343 residents of Tagulandang and Ruang islands remained in evacuation centers because of eruptions from Ruang. According to PVMBG daily white steam-and-gas plumes that were sometimes dense rose as high as 700 m above the summit and drifted in multiple directions during 15-21 May. The Alert Level was lowered to 2 (the second lowest level on a scale of 1-4) at 0900 on 18 May and the public was warned to stay 2 km away from the active crater.
Sources: Badan Nacional Penanggulangan Bencana (BNPB), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Sheveluch
KVERT reported that the Karan-1 lava dome on Sheveluch’s SW flank continued to grow during 9-16 May. An intense and large thermal anomaly over the dome was identified in satellite images during 9-12 May; the dome was obscured by weather clouds on the other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Slamet
PVMBG reported that daily white emissions rose 50-500 m above Slamet’s summit and drifted W during 15-21 May. The Alert Level remained at 2 (on a scale of 1-4). On 16 May the exclusion zone was increased from 2 km to 3 km based on monitoring data.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Spurr
On 15 May AVO reported that elevated seismicity at Spurr was consistent with an intrusion of magma deep beneath the volcano. An extended outage of the seismic network occurred during February-April; elevated seismicity was already occurring when the network returned on 3 April. An average of four earthquakes per day were located after that time, with a maximum of 33 earthquakes detected on 26 April. They were typically smaller than M 1 and were located near the summit and as deep as 30 km below sea level. This activity represents an increase in earthquake rate and occurrence of deeper (>20 km) low-frequency earthquakes compared to recent years. Minor uplift of the ground surface at the volcano of about 1 cm was detected in local GPS data beginning in November 2023, which was a deviation from the long-term trend and may be related to the seismicity. Minor steaming from fumaroles in the summit crater area was sometimes visible; no notable changes to the ice-and-snow cover or gas-and-steam emissions were observed in association with these geophysical observations. A short observational flight was conducted on 14 May. The Volcano Alert Level remained at Normal (the lowest level on a four-level scale) and the Aviation Color Code remained at Green (the lowest color on a four-color scale).
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Taal
PHIVOLCS reported ongoing unrest at Taal during 13-21 May. Daily upwelling of gases and hot fluids in the lake generated steam-and-gas plumes that rose as high as 2.4 km above the crater rim and drifted WNW. Sulfur dioxide emissions increased to 5,094 tonnes per day (t/d) on 13 May. A phreatic event began at 1345 on 15 May, lasted about five minutes, and produced a steam plume that rose 500 m above Main Crater rim and drifted W and NW. On 16 May a series of short phreatic events were visible in webcam images and detected by the seismic network during 0854-0857, 1107-1110, 1348-1350, 1737-1738, and a fifth that ended at 2303. The events produced steam plumes that rose 50-300 m and drifted WNW. Sulfur dioxide emissions decreased to 3,823 t/d on 20 May. The Alert Level remained at 1 (on a scale of 0-5), and PHIVOLCS reminded the public that the entire Taal Volcano Island was a Permanent Danger Zone (PDZ) and to take extra precautions around Main Crater, when boating on Taal Lake, and along the Daang Kastila fissure.
Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
Report for Ubinas
Instituto Geofísico del Perú (IGP) reported that thermal anomalies from the main crater floor at Ubinas were identified daily during 15-21 May, except for on 15 May. Daily gas-and-steam plumes rose as high as to 1.6 km above the crater rim. The Alert Level remained at Yellow (the second level on a four-color scale) and the public was warned to stay 2 km away from the crater.
Source: Instituto Geofísico del Perú (IGP)
Report for Aira
JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 13-20 May with nighttime crater incandescence. An explosion at 1442 on 15 May generated an ash plume that rose 2 km above the crater rim and drifted SE and ejected blocks as far as 1.1 km from the crater. Sulfur dioxide emissions were elevated, averaging 700 tons per day on 17 May. Explosions at 1928 on 18 May and 0121 on 20 May produced ash plumes that rose 1.2 and 2.3 km, respectively, above the crater rim and drifted W. The explosions ejected blocks 0.5-1.1 km from the crater. An eruptive event at 1442 on 20 May generated an ash plume that rose 1.2 km and drifted S. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both craters.
Source: Japan Meteorological Agency (JMA)
Report for Campi Flegrei
INGV reported that a seismic swarm at Campi Flegrei consisted of about 150 earthquakes recorded from 1951 on 20 May to 0031 on 21 May. The largest event in the swarm, a M 4.4 located at a depth of 2.6 km beneath the Solfatara, was the largest recorded since the current cycle of seismicity associated with uplift began in 2005. A total of 450 earthquake events were recorded the previous month. The rate of inflation was 2 cm per month and remained unchanged. The report noted that during a 1982-84 seismic crisis there were more than 1,300 monthly events recorded, with associated uplift as high as 9 cm per month.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Dukono
PVMBG reported that the eruption at Dukono was ongoing during 15-21 May. Dense white steam-and-gas plumes rose 500-600 m and drifted N on 15 May. Gray-and-white ash plumes rose 400-1,300 m above the summit and drifted E on most of the other days; weather conditions prevented views on 21 May. The Alert Level remained at Level 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Ebeko
KVERT reported that moderate explosive activity was ongoing at Ebeko during 10-17 May According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 13-14 and 16 May generated ash plumes that rose as high as 2.5 km (8,200 ft) a.s.l. and drifted NE. A thermal anomaly was identified in satellite images on 16 May; on other days either no activity was observed or weather conditions prevented views. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are UTC; specific events are in local time where noted.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Fernandina
Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN) reported that the eruption at Fernandina likely ended on 8 May. Daily thermal anomalies from the cooling lava flows on the SSE flank were identified in satellite images during 14-21 May. The number and intensity of the thermal anomalies were variable but decreased overall and were low by the end of the week. Sulfur dioxide emissions were 13 tons per day at 1356 on 15 May.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Report for Great Sitkin
AVO reported that slow lava effusion in Great Sitkin’s summit crater likely continued during 15-21 May. Seismicity was low with daily, small, occasional earthquakes. The active portion of the lava flow was warm and snow-free, and steaming was visible in occasional clear satellite and webcam views; weather clouds sometimes prevented such views. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Lewotobi
PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 15-21 May. White steam-and-gas plumes rose as high as 100 m above the summit and drifted NW, W, and SW during 15, 17-18, and 21 May. Gray-and-white ash plumes rose 100 m above the summit and drifted W, SW, and NE during 16 and 19-20 May. The Alert Level remained at 2 (the second lowest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 2-km radius around Laki-laki crater, 3 km to the NNE, and 5 km on the NE flanks.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Lewotolok
PVMBG reported that the eruption at Lewotolok continued during 11-21 May. A lava flow breached the W crater rim on 11 May and traveled 1.2 km down the W flank by 12 May. White-and-gray ash plumes rose as high as 600 m and drifted W and NW during 13, 15, and 17-20 May. White steam-and-gas plumes rose 300-500 m above the summit and drifted NW, W, and SW on the other days during 11-21 May. The lava flow on the W flank had not advanced by 20 May. The Alert Level remained at 3 (on a scale of 1-4) and visitors and residents of Lamawolo, Lamatokan, and Jontona were warned to stay 2 km away from the vent and 3 km away from the vent on the S and SE flanks.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Antara News, Antara News
Report for Merapi
BPPTKG reported that the eruption at Merapi (on Java) continued during 10-16 May. Seismicity had decreased compared to the previous week. The SW lava dome produced 68 lava avalanches that traveled as far as 2.1 km down the Bebeng drainage on the SW flank. Morphological changes to the SW lava dome were due to continuing effusion and collapses of material. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location.
Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)
Report for Popocatepetl
CENAPRED reported that eruptive activity continued at Popocatépetl during 14-21 May. The seismic network recorded long-period events totaling 30-85 per day that were sometimes accompanies by steam-and-gas emissions; steam, gas, and ash emissions were visible during 18-19 May. The seismic network also recorded 98 minutes to more than 8.5 hours of tremor each day and a few volcano-tectonic earthquakes. According to the Washington VAAC daily ash plumes visible in webcam and satellite images rose to 5.5-6.1 km (18,000-20,000 ft) a.s.l. (or as high as 700 m above the crater rim) and drifted SW, SW, and WSW. Thermal anomalies in the crater were detected during 16-17 May. The Alert Level remained at Yellow, Phase Two (the middle level on a three-color scale) and the public was warned to stay 12 km away from the crater.
Sources: Centro Nacional de Prevencion de Desastres (CENAPRED), Washington Volcanic Ash Advisory Center (VAAC)
Report for Reventador
IG-EPN reported that an eruption at Reventador was ongoing during 14-21 May. Seismicity was characterized by 46-78 daily explosions, long-period earthquakes, harmonic tremor, volcano-tectonic events, and tremor associated with emissions. Ash-and-gas plumes rose as high as 1.1 km above the crater rim and drifted NW, W, and SW during 14-18 and 21 May. Weather conditions sometimes prevented views, especially during 19-20 May. Incandescence at the crater was visible during most nights and avalanches of incandescent material descended the flanks as far as 500 m from the summit on a few of the nights. Secretaría de Gestión de Riesgos maintained the Alert Level at Orange (the second highest level on a four-color scale).
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Secretaría de Gestión de Riesgos (SGR)
Report for Sangay
IG-EPN reported that high levels of eruptive activity continued at Sangay during 14-21 May. The seismic network recorded 99-1,212 daily explosions during the week. Gas-and-ash plumes visible in webcam and/or satellite images on most days rose as high as 1 km above the summit and drifted NW and SW; weather conditions often hindered views during the week. Incandescent material at the crater was visible during dark hours on most nights and incandescent avalanches descending the SE flank as far as 1.8 km during 15-16 May. Secretaría de Gestión de Riesgos (SGR) maintained the Alert Level at Yellow (the second highest level on a four-color scale).
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Secretaría de Gestión de Riesgos (SGR)
Report for Semeru
PVMBG reported that eruptive activity continued at Semeru during 15-21 May. Daily white-and-gray ash plumes rose 300-900 m above the summit and drifted in multiple directions. Several additional eruptive events were recorded during the week by the seismic network, though plumes were not visually confirmed. According to news articles pyroclastic flows descended the SE flank as far as 3 km on 18 May. Pyroclastic flows descended the SE flank during 20-21 May, though the distances were unknown due to weather conditions. The Alert Level remained at 3 (the third highest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Antara News, Antara News
Report for Stromboli
INGV reported that eruptive activity continued at Stromboli during 13-19 May. Webcam images showed Strombolian activity at two vents in Area N (one at N1 and one at N2), within the upper part of the Sciara del Fuoco, and from two vents at S2 in Area C-S (South-Central Crater) on the crater terrace. At Area N, low- to medium-intensity explosive activity ejected coarse material (bombs and lapilli) less than 80 m and 150 m from vents in the N1 and N2 sectors, respectively. The average frequency of explosions from this area was 10-18 events per hour. Spattering at N1 was almost continuous and intense at times. At Area C-S, explosive activity at two vents in sector S2 ejected both coarse and fine material higher than 150 m above the vent. The average explosion rate was 5-8 events per hour.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Suwanosejima
JMA reported that eruptive activity at Suwanosejima's Ontake Crater continued during 13-20 May. Crater incandescence was observed nightly in webcam images. Emissions rose as high as 800 m above the crater rim and blocks were ejected as far as 200 m from the crater’s center; no explosions were detected. The Alert Level remained at 2 (on a 5-level scale) and the public was warned to stay at least 1.5 km away from the crater.
Source: Japan Meteorological Agency (JMA)
Report for Villarrica
SERNAGEOMIN reported that the eruption at Villarrica continued. A volcano-tectonic evet was recorded by the seismic network at 0428 on 18 May. At 0911 on that same day a gas-and-ash plume rose 340 m above the crater rim and drifted ESE. The Volcanic Alert Level remained at Yellow (the second lowest level on a four-level scale) and the public was warned to stay 500 m away from the active crater.
Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)