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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 25 May-31 May 2016
Name Country Volcanic Province Eruption Start Date Report Status
Bristol Island United Kingdom South Sandwich Volcanic Arc New
Etna Italy Sicily Volcanic Province New
Piton de la Fournaise France Reunion Hotspot Volcano Group New
Santa Maria Guatemala Central America Volcanic Arc 1922 Jun 22 New
Turrialba Costa Rica Central America Volcanic Arc New
Alaid Russia Kuril Volcanic Arc Continuing
Bagana Papua New Guinea Solomon Volcanic Arc 2000 Feb 28 (in or before) Continuing
Chirpoi Russia Kuril Volcanic Arc Continuing
Cleveland United States Aleutian Ridge Volcanic Arc Continuing
Colima Mexico Trans-Mexican Volcanic Belt Continuing
Dukono Indonesia Halmahera Volcanic Arc 1933 Aug 13 Continuing
Kilauea United States Hawaiian-Emperor Hotspot Volcano Group Continuing
Klyuchevskoy Russia Eastern Kamchatka Volcanic Arc Continuing
Nevado del Ruiz Colombia Andean Northern Volcanic Arc 2014 Nov 18 Continuing
Sangay Ecuador Andean Northern Volcanic Arc 2019 Mar 26 Continuing
Semeru Indonesia Sunda Volcanic Arc 2017 Jun 6 Continuing
Sheveluch Russia Eastern Kamchatka Volcanic Arc 1999 Aug 15 Continuing
Sinabung Indonesia Sunda Volcanic Arc Continuing
Tengger Caldera Indonesia Sunda Volcanic Arc 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 Bristol Island
According to NASA's Earth Observatory, a Moderate Resolution Imaging Spectroradiometer (MODIS) satellite image of Bristol Island acquired on 28 May showed an ash plume from Mt. Sourabaya drifting NE. Based on satellite image analysis, the Buenos Aires VAAC reported that during 29-31 May gas plumes with possible minor ash content drifted as far as 185 km N, NNE, and SE at an altitude of 1.5 km (5,000 ft) a.s.l.
Sources: NASA Earth Observatory, Buenos Aires Volcanic Ash Advisory Center (VAAC)
Report for Etna
INGV reported that at around noon on 20 May Strombolian activity was visible at Etna's Voragine (VOR) crater and produced explosion noises audible across a large area on the S and E flanks. At night the activity intensified with explosions occurring at two or three vents, contemporaneous with renewed inflation of the summit area. Just after 0400 volcanic tremor amplitude rapidly increased and the Strombolian explosions turned into pulsating jets of lava, launching incandescent bombs 1 km S; an ash plume drifted SSE. A thermal camera also recorded activity from a vent in the S portion of Northeast Crater (NEC). Observers noted that a fracture had formed on the SE flank of the central cone. In addition, an effusive vent in the saddle between the cone and the old cone of the Southeast Crater produced a small lava flow that traveled towards the Valle del Leone. Activity decreased around 0500 and was over at about 0600.

On 22 May a vent on the upper E flank of New Southeast Crater cone produced a series of ash emissions which rose several hundred meters above the summit and dispersed. Some of the emissions had a thermal signature, indicating the presence of hot material. That evening Strombolian activity resumed at NEC; the rate and intensity of the activity fluctuated through the night. The strongest explosions ejected incandescent bombs up to a few hundred meters above the crater rim and onto the flanks. On 23 May sporadic ash emissions continued from the vent on the upper E flank of the New Southeast Crater cone.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Piton de la Fournaise
OVPDLF reported that CO2 gas emission, deformation, and seismicity at Piton de la Fournaise began to slowly increase on 16 May, and then seismicity significantly increased at 1140 on 25 May. Tremor began at 0805 on 26 May, characteristic of an ongoing eruption, likely from a new fissure near Château Fort crater. Bad weather prevented visual observations of the area at first, though at 0900 ground observers confirmed a new eruption. Later that day scientists and reporters saw about six lava fountains (some were 40-50 m high) during brief aerial surveys and a cinder cone being built on a flat area at 1850 elevation about 1-1.5 km SE of Castle Crater. RSAM values significantly decreased at 1800, increased slightly, and then stabilized. On 27 May tremor levels significantly dropped at 0845 and then ceased at 1100. Signals indicative of degassing continued.
Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
Report for Santa Maria
In a special report posted on 25 May, INSIVUMEH reported energetic explosive activity at Caliente cone, part of Santa María's Santiaguito lava-dome complex. Loud explosions at 0804 and 0918 generated mushroom-shaped ash clouds that rose as high as 2.5 km and drifted more than 40 km WSW. Pyroclastic flows traveled 2 km E, S, and W, in the San Isidro and Cabello de Ángel drainages. Ashfall was reported in areas downwind including El Nuevo Palmar (12 km SSW), San Felipe (15 km SSW), and Retalhuleu (27 km SW), the villages of Las Marias, Loma Linda, and San Marcos (10 km SW), Palajunoj (18 km SSW), and the El Faro (SW flank), La Florida (5 km S), Patzulin (SW flank), and El Patrocinio ranches. During 28-29 May white-and-gray plumes rose 400 m above the cone and drifted SW.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Turrialba
OVSICORI-UNA reported that a strong explosion detected at Turrialba at 2145 on 24 May generated ash plumes that rose 3.5 km above the volcano and drifted SW. The event ejected large rocks around the crater. About one hour later ashfall was reported in multiple areas, including Santa Rosa de Oreamuno, Santa Cecilia de Heredia, and San Francisco de Heredia. At 0015 on 25 May tremor amplitude increased, and at 0030 explosions ejected abundant amounts of ash and incandescent rocks. At 0812 a gas-and-ash plume rose 500 m above the active craters. Large amounts of ash (deposits 2-7 mm thick) fell in the several neighborhoods in the towns of Carthage, Heredia (38 km W), San José (70 km W), and Alajuela (49 km W). Tremor was continuous throughout the day but the amplitude had decreased by 1900. Ash emissions continued, with plumes rising 500 m above the volcano. Tremor decreased at around 0200 on 27 May; emissions likely did not contain ash, which was confirmed at dawn. Ashfall and a strong sulfur odor was reported by residents of Aquiares (11 km SSE), Santa Cruz de Turrialba (8 km SSE), and central Turrialba. Seismicity remained low during 28-31 May, and gas emissions from the crater persisted.
Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)
Report for Alaid
KVERT reported that moderate activity at Alaid continued during 20-27 May. Satellite images showed a thermal anomaly over the volcano during 20-21 May. 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 Bagana
Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 25-29 May ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 75 km in multiple directions.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Chirpoi
SVERT reported that a thermal anomaly over Snow, a volcano of Chirpoi, was detected in satellite images during 23-25 and 28 May. The Aviation Color Code remained at Yellow.
Source: Sakhalin Volcanic Eruption Response Team (SVERT)
Report for Cleveland
AVO reported that a small lava dome in Cleveland's summit crater first observed on 18 May had grown to about 60 m in diameter, though it had not changed since 23 May. Weakly elevated surface temperatures detected in satellite images during 25-26 May were consistent with the presence of the new lava dome. Seismicity remained low through 31 May. The Level of Concern Color Code remained at Orange and the Volcano Alert Level remained at Watch.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Colima
Based on satellite images, the Washington VAAC reported that on 27 May a possible ash plume from Colima rose to an altitude of 5.8 km (19,000 ft) a.s.l. and drifted NE.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Dukono
Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 25-30 May ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted as far as 185 km NW, W. WSW, and SW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Kilauea
HVO reported that around 0650 on 24 May new lava flows broke out from the flanks of Kilauea's Pu'u 'O'o cone. The first flow originated about 250 m from the rim of the cone's NE flank and traveled NW, and the second flow came from an area on the E flank, about 500 m from the cone's rim, and traveled SE. By 0830 the first flow was about 1 km long and the second one was about 700 m long. By the same time on 25 May the first flow had become channelized and a new 950-m-long lobe had descended NW. The other flow was active but had not significantly advanced.

The lava lake continued to circulate and eject spatter in the Overlook vent during 25-31 May; a rockfall into the lake on 26 May and briefly triggered sloshing and agitation of the lake. The June 27th NE-trending lava flow continued to be active within 5 km NE of Pu'u 'O'o Crater. Webcams recorded glow from multiple spatter cones on the Pu'u 'O'o Crater floor. The new lava flows extended about 1.2 km NW and SE by 27 May and continued to be active through 29 May.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Klyuchevskoy
KVERT reported that a Strombolian eruption at Klyuchevskoy continued during 20-27 May. Satellite and video data showed a lava flow effusing on the SE flank, down the Apakhonchich drainage. Satellite images showed an intense daily thermal anomaly over the volcano. The Aviation Color Code was raised to Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Nevado del Ruiz
Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 24-30 May seismicity at Nevado del Ruiz was characterized by long-period and very-long-period earthquakes, episodes of continuous tremor, and pulses of volcanic tremor associated with gas-and-ash emissions. Significant amounts of water vapor and gas rose from the crater during the week. A gas, steam, and ash plume rose 1.8 km above the crater rim and drifted NW and W on 25 May. A minor thermal anomaly near Arenas Crater was detected in satellite images on 27 May. The Alert Level remained at III (Yellow; the second lowest level on a four-color scale).
Source: Servicio Geológico Colombiano (SGC)
Report for Sangay
Based on satellite images and wind data, the Washington VAAC reported that during 25-27 and 30-31 May ash plumes from Sangay rose to altitudes of 5.8-6.7 km (19,000-22,000 ft) a.s.l. and drifted NE, E, SW, and W. A hotspot was detected during 26-27 May.
Source: Washington Volcanic Ash Advisory Center (VAAC)
Report for Semeru
Based on analysis of satellite images, the Darwin VAAC reported that on 25 and 27 May ash plumes from Semeru rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted 25-40 km SW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Sheveluch
KVERT reported that during 20-27 May lava-dome extrusion onto Sheveluch’s N flank was accompanied by strong fumarolic activity, dome incandescence, ash explosions, and hot avalanches. Satellite images showed an intense daily thermal anomaly over the dome. The Aviation Color Code remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Sinabung
Based on satellite images and information from PVMBG, the Darwin VAAC reported that during 26-29 May ash plumes from Sinabung rose to altitudes of 3.6-4.9 km (12,000-16,000 ft) a.s.l.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Tengger Caldera
Based on satellite images, wind data, and information from PVMBG, the Darwin VAAC reported that during 28-31 May ash plumes from Tengger Caldera's Bromo cone rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted as far as 55 km NW, SW, S, and NNE.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)