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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 17 May-23 May 2017
Name Country Eruption Start Date Report Status
Manam Papua New Guinea 2014 Jun 29 New
Nishinoshima Japan New
Poas Costa Rica 2023 Dec 1 New
Sheveluch Russia 1999 Aug 15 New
Aira Japan 2017 Mar 25 Continuing
Bagana Papua New Guinea 2000 Feb 28 (in or before) Continuing
Bezymianny Russia 2016 Dec 5 Continuing
Bogoslof United States Continuing
Cleveland United States Continuing
Colima Mexico Continuing
Dukono Indonesia 1933 Aug 13 Continuing
Ebeko Russia 2022 Jun 11 Continuing
Ibu Indonesia 2008 Apr 5 Continuing
Kambalny Russia Continuing
Kilauea United States Continuing
Klyuchevskoy Russia Continuing
Langila Papua New Guinea 2015 Oct 22 (?) Continuing
Piton de la Fournaise France Continuing
Sabancaya Peru 2016 Nov 6 Continuing
San Miguel El Salvador Continuing
Sinabung Indonesia Continuing
Turrialba Costa Rica Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,140 individual reports over 1,221 weeks (average of 16 per week) on 334 different volcanoes.

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Agung Cotopaxi Iliamna Little Sitkin Poas Sulu Range
Ahyi Cuicocha Iliwerung Llaima Popocatepetl Sumbing
Aira Cumbal Inielika Lokon-Empung Purace Sundoro
Akan Dabbahu Ioto Lonquimay Puyehue-Cordon Caulle Suoh
Alaid Davidof Irazu Lopevi Rabaul Suretamatai
Alu-Dalafilla Dempo Iya Machin Raikoke Suwanosejima
Ambae Descabezado Grande Izu-Torishima Makushin Ranakah Taal
Ambang Dieng Volcanic Complex Jackson Segment Maly Semyachik Raoul Island Tair, Jebel at
Ambrym Dukono Kaba Manam Rasshua Takawangha
Anatahan East Epi Kadovar Manda Hararo Raung Talang
Aniakchak Ebeko Kaitoku Seamount Marapi Redoubt Tambora
Antillanca Volcanic Complex Ebulobo Kama'ehuakanaloa Maroa Reventador Tanaga
Antuco Edgecumbe Kambalny Martin Reykjanes Tandikat-Singgalang
Apoyeque Egon Kanaga Masaya Rincon de la Vieja Tangkoko-Duasudara
Arenal Ekarma Kanlaon Maule, Laguna del Rinjani Tangkuban Parahu
Asamayama Eldey Karangetang Mauna Loa Ritter Island Tara, Batu
Askja Erebus Karkar Mayon Rotorua Ta'u
Asosan Erta Ale Karthala McDonald Islands Ruang Taupo
Atka Volcanic Complex Etna Karymsky Melebingoy Ruapehu Telica
Augustine Etorofu-Yakeyama [Grozny Group] Kasatochi Melimoyu Ruby Tenerife
Avachinsky Eyjafjallajokull Katla Merapi Ruiz, Nevado del Tengger Caldera
Awu Fagradalsfjall Katmai Midagahara Sabancaya Three Sisters
Axial Seamount Fernandina Kavachi Misti, El Sakar Tinakula
Azul, Cerro Fogo Kelimutu Miyakejima Salak Tofua
Azumayama Fonualei Kelud Momotombo San Cristobal Tokachidake
Bagana Fournaise, Piton de la Kerinci Monowai San Miguel Tolbachik
Balbi Fourpeaked Ketoi Montagu Island San Vicente Toliman
Bamus Fuego Kharimkotan Moyorodake [Medvezhia] Sangay Tongariro
Banda Api Fujisan Kick 'em Jenny Mutnovsky Sangeang Api Trident
Bardarbunga Fukutoku-Oka-no-Ba Kie Besi Myojinsho Santa Ana Tungurahua
Barren Island Galeras Kikai Nabro Santa Maria Turrialba
Batur Galunggung Kilauea Negra, Sierra Sao Jorge Ubinas
Bezymianny Gamalama Kirishimayama Negro, Cerro Sarigan Ugashik-Peulik
Bogoslof Gamkonora Kita-Ioto Nightingale Island Sarychev Peak Ukinrek Maars
Brava Gareloi Kizimen Nishinoshima Saunders Ulawun
Bristol Island Gaua Klyuchevskoy Nisyros Savo Unnamed
Bulusan Gorely Kolokol Group Novarupta Semeru Unnamed
Calbuco Great Sitkin Koryaksky NW Rota-1 Semisopochnoi Veniaminof
Callaqui Grimsvotn Krakatau Nyamulagira Seulawah Agam Villarrica
Cameroon Guagua Pichincha Krummel-Garbuna-Welcker Nyiragongo Sheveluch Vulcano
Campi Flegrei Guallatiri Krysuvik-Trolladyngja Ofu-Olosega Shishaldin West Mata
Campi Flegrei del Mar di Sicilia Guntur Kuchinoerabujima Okataina Simbo Westdahl
Cayambe Hachijojima Kurikomayama Okmok Sinabung Whakaari/White Island
Chachadake [Tiatia] Hakoneyama Kusatsu-Shiranesan Ontakesan Sinarka Witori
Chaiten Heard Kverkfjoll Oraefajokull Siple Wolf
Chiginagak Hekla La Palma Osorno Sirung Wrangell
Chikurachki Helgrindur Lamington Pacaya Slamet Yakedake
Chiles-Cerro Negro Hierro Lamongan Pagan Snaefellsjokull Yasur
Chillan, Nevados de Hokkaido-Komagatake Langila Palena Volcanic Group Soputan Yufu-Tsurumi
Chirinkotan Home Reef Lanin Paluweh Sorikmarapi Zaozan [Zaosan]
Chirpoi Hood Lascar Panarea Sotara Zavodovski
Ciremai Huaynaputina Late Papandayan Soufriere Hills Zhupanovsky
Cleveland Hudson, Cerro Lateiki Pavlof Soufriere St. Vincent Zubair Group
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
 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 Manam
Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 18-20 May ash plumes from Manam rose 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted W and WNW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Nishinoshima
The Japan Coast Guard reported that during an overflight of Nishinoshima during 1300-1345 on 2 May observers noted frequent (every 40-60 seconds) Strombolian explosions at a new pyroclastic cone in the crater. Ash plumes rose 500 m. Two lava flows originating from the N part of the cone traveled 180 m SW and 170 m W, and entered the ocean. The island continued to grow and was estimated to be 2 km E to W and about 1.9 km N to S, with an area of 2.75 square kilometers (it was 2.68 square kilometers on 15 September 2016).
Source: Japan Coast Guard
Report for Poas
OVSICORI-UNA reported that tremor levels at Poás were at low-to-moderate levels during 17-21 May and at higher levels during 22-23 May. Low-amplitude long-period earthquakes were recorded on 19 May, and some low-frequency and volcano-tectonic events were detected during 21-22 May. Plumes consisted mainly of gas and water vapor, but sometimes included solid material, and rose no more than 1 km above the vent.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Report for Sheveluch
KVERT reported that during 13-14 May a series of explosions at Sheveluch generated ash plumes that rose 4.5-5 km (14,800-16,400 ft) a.s.l. and drifted SW and SE. Powerful explosions on 16 May generated ash plumes that rose as high as 11 km (36,100 ft) a.s.l. and drifted about 150 km ENE. Pyroclastic flows descended the S flank. Two explosions were detected on 18 May. Ash plumes during 16-19 May drifted 400 km ENE. The Aviation Color Code (ACC) remained at Orange during 13-19 May, except for a few hours on 16 May when the strong explosions prompted KVERT to raise the ACC to Red.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Aira
JMA reported that 10 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) were detected during 15-18 May. One of the events, an explosion at 2302 on 17 May, generated a large ash plume that rose 3 km above the crater rim and ejected material 500-800 m from the crater. That same day at 1526 an explosion at Minamidake summit crater produced an ash plume that rose 1.1 km above the crater. At 0058 on 19 May a plume rose 1.4 km above Showa Crater's rim. Very small events occasionally occurred at Minamidake summit crater during 19-22 May. The Alert Level remained at 3 (on a 5-level scale).
Source: Japan Meteorological Agency (JMA)
Report for Bagana
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 20-22 May ash plumes from Bagana rose 2.4 km (8,000 ft) a.s.l. and drifted W.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Bezymianny
KVERT reported gas-and-steam activity at Bezymianny during 12-19 May, and a thermal anomaly identified in satellite images daily. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Bogoslof
AVO reported that the eruption at Bogoslof which began at 2232 on 16 May lasted about 73 minutes. Trace amounts of ash fell in the community of Nikolski on Umnak Island. Later that day the Aviation Color Code (ACC) was lowered to Orange and the Volcano Alert Level (VAL) was lowered to Watch; no further ash emissions were detected and seismicity was low. Satellite data showed that the event altered the N coastline of the island. The crater lake was breached with a 550-m-wide gap along the N shore, and the NE shore had been extended 300 m from new tephra deposits.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Cleveland
AVO reported that a short-lived explosion at Cleveland was detected in both seismic and infrasound data at 1938 on 16 May; the seismic signal lasted about 11 minutes. An ash cloud observed in satellite images rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted SW for about five hours. The explosions completely destroyed the lava dome that was emplaced in the summit crater during April-May. 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 Colima
On 19 May the Centro Universitario de Estudios e Investigaciones de Vulcanologia - Universidad de Colima reported that during the previous week seismic data revealed 25 high-frequency events, 15 long-period events, 2.2 hours of tremor, 12 landslides, and three low-intensity explosions. During 15-16 May sulfur dioxide emissions were below detectable limits (8.6 t/d).
Source: Centro Universitario de Estudios Vulcanológicos (CUEV) - Universidad de Colima
Report for Dukono
Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 18-23 May ash plumes from Dukono rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted in multiple directions.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Ebeko
KVERT reported that on 15 May explosions at Ebeko were observed by residents of Severo-Kurilsk (Paramushir Island) about 7 km E. Ash plumes rose as high as 2 km (6,600 ft) a.s.l. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Ibu
Based on analyses of satellite imagery and information from PVMBG, the Darwin VAAC reported that during 19-20 and 23 May ash plumes from Ibu rose 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted NE, E, and S.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Kambalny
On 19 May KVERT reported that the eruption at Kambalny likely had ended, with only gas-and-steam activity observed during the previous month. The explosive phase began on 24 March and ended on 10 April. The Aviation Color Code was lowered to Green.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Kilauea
During 17-23 May HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater; the lake rose as high as 15 m below the crater rim and was visible from Hawaii Volcanoes National Park's Jaggar overlook. Webcams recorded incandescence from long-active sources within Pu'u 'O'o Crater, from a vent high on the NE flank of the cone, and from a small lava pond in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu'u 'O'o Crater's E flank, continued to enter the ocean at Kamokuna adding to a growing delta. Surface lava flows were active above and on the upper slopes of the pali.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Klyuchevskoy
Based on video and satellite data, KVERT reported that explosions at Klyuchevskoy on 17 May generated ash plumes that rose to 6 km (19,700 ft) a.s.l. and drifted about 180 km N and NE. A weak thermal anomaly was identified daily. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Langila
Based on analyses of satellite imagery and wind model data, the Darwin VAAC reported that on 19 May an ash plume from Langila rose 4.6 km (15,000 ft) a.s.l. and drifted almost 170 km WSW and dissipated. During 19-20 May ash plumes drifted N and NNW at 1.8 km (6,000 ft) a.s.l. On 23 May ash plumes rose 2.1 and 3 km (7,000 and 10,000 ft) a.s.l. and drifted NW and SW, respectively.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Piton de la Fournaise
OVPF reported that a seismic crisis at Piton de la Fournaise began at 1340 on 17 May and was accompanied by rapid deformation that suggested rising magma; volcanic tremor was recorded at 2010. The seismic and deformation activity was located in the NE part of l’Enclos Fouqué caldera. During an overflight at 1100 on 18 May scientists observed no surface activity at the base of the Nez Coupé de Sainte Rose rampart (on the N side of the volcano) nor outside of l'Enclos Fouqué caldera, and suggested that fractures opened but did not emit lava.

Seismicity increased at 0400 on 18 May. The number of shallow (<2 km depth) and deep (>2 km depth) volcano-tectonic earthquakes progressively decreased over the next three days: 40 shallow and 22 deep on 18 May, 18 shallow and 22 deep on 19 May, 7 shallow and 9 deep on 20 May, 8 shallow and 1 deep on 21 May. Carbon dioxide concentrations in soils measured at remote stations were high. During a field visit on 22 May scientists mapped the deformation associated with the 17 May event and measured displacements that did not exceed 35 cm. On 23 May OVPF reported that the 17-18 May activity resulted in two new zones of fumaroles that followed the trends seen in seismic and deformation data.
Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Report for Sabancaya
Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that during 15-21 May explosive activity at Sabancaya was similar to the previous week, with an average of 39 explosions detected per day. The number and magnitude of long-period and hybrid events was low. Gas-and-ash plumes rose as high as 4.2 km above the crater rim and drifted more than 40 km NE, E, and SE. The MIROVA system detected six thermal anomalies.
Sources: Instituto Geofísico del Perú (IGP), Instituto Geológico Minero y Metalúrgico (INGEMMET)
Report for San Miguel
On 19 May SNET reported that during the previous 24 hours RSAM values at San Miguel continued to decrease, fluctuating between 69 and 80 units (typical background levels average 50 units). Sulfur dioxide flux was also lower, though changing winds may have affected readings.
Source: Servicio Nacional de Estudios Territoriales (SNET)
Report for Sinabung
Based on PVMBG observations, webcam and satellite images, and wind data, the Darwin VAAC reported that during 17-20 and 24 May ash plumes from Sinabung rose 4.3-8.8 km (14,000-29,000 ft) a.s.l. and drifted in multiple directions. BNPB reported a high-intensity eruption at the volcano on 20 May. An ash plume rose 4 km and drifted SE. There were 2,038 families (7,214 people) displaced to eight shelters, and an additional 2,863 people living in refugee camps. The Alert Level remained at 4 (on a scale of 1-4), with an exclusion zone of 7 km from the volcano on the SSE sector, and 6 km in the ESE sector, and 4 km in the NNE sector.
Sources: Badan Nacional Penanggulangan Bencana (BNPB), Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Turrialba
OVSICORI-UNA reported that low-to-moderate amplitude tremor was recorded at Turrialba during 17-23 May. Small numbers of volcano-tectonic and long-period events were recorded during 18-19 May, and low-frequency and volcano-tectonic events were detected during 21-22 May. Ash emission were observed during 17-23 May, rising as high as 1 km above the vent. Ashfall was reported in El Tapojo and Juan Viñas (15 km SSE) during 17-18 May, and in Capellades (along with a strong sulfur odor) during 19-20 May.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)