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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 5 April-11 April 2023
Name Location Eruption Start Date Report Status
Ambae Vanuatu New
Bezymianny Central Kamchatka (Russia) 2016 Dec 5 New
Nevado del Ruiz Colombia 2014 Nov 18 New
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Cotopaxi Ecuador Continuing
Ebeko Paramushir Island (Russia) 2022 Jun 11 Continuing
Fuego South-Central Guatemala 2002 Jan 4 Continuing
Great Sitkin Andreanof Islands (USA) 2021 May 25 Continuing
Karangetang Sangihe Islands 2018 Nov 25 Continuing
Katmai Alaska Continuing
Krakatau Sunda Strait Continuing
Lascar Northern Chile Continuing
Lewotolok Lembata Island 2020 Nov 27 Continuing
Merapi Central Java 2020 Dec 31 Continuing
Nishinoshima Izu Islands Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
Semeru Eastern Java 2017 Jun 6 Continuing
Semisopochnoi Aleutian Islands (USA) Continuing
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 19,996 individual reports over 1,215 weeks (average of 16 per week) on 332 different volcanoes.

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


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



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

 Criteria & Disclaimers

Criteria



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

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

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

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

Disclaimers



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

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

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

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

5. USGS Disclaimer Statement for this Website:

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

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

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

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

 Acronyms and Abbreviations

a.s.l. - above sea level

AVO - Alaska Volcano Observatory

AVHRR - Advanced Very High Resolution Radiometer

CENAPRED - Centro Nacionale de Prevencion de Desastres (México)

CONRED - Coordinadora Nacional para la Reducción de Desastres

COSPEC - Correlation Spectrometer

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

CVO - Cascades Volcano Observatory (USGS)

GMS - Geostationary Meteorological Satellite

GOES - Geostationary Operational Environmental Satellite

GVO - Goma Volcano Observatory

GVP - Global Volcanism Program (Smithsonian Institution)

HVO - Hawaiian Volcano Observatory (USGS)

ICE - Instituto Costarricense de Electricidad (Costa Rica)

IG - Instituto Geofísico (Ecuador)

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

INETER - Instituto Nicaragüense de Estudios Territoriales (Nicaragua)

INGEMMET - Instituto Geológical Minero y Metalúrgico (Peru)

INGEOMINAS - Instituto Colombiano de Geología y Minería (Colombia)

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

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

IRD - Institut de Recherche pour le Développement (France)

JMA - Japanese Meteorological Agency

KEMSD - Kamchatkan Experimental and Methodical Seismilogical Department

KVERT - Kamchatkan Volcanic Eruption Response Team

M - magnitude

METEOSAT - Meteorological Satellite

MEVO - Mount Erebus Volcano Observatory

MODIS - Moderate Resolution Imaging Spectroradiometer

MVO - Montserrat Volcano Observatory

MWO - Meteorological Watch Office

NEIC - National Earthquake Information Center

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

NOAA - National Oceanic and Atmospheric Administration

NOTAM - Notice to Airmen

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

OFDA - Office of US Foreign Disaster Assistance

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

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

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

PHIVOLCS - Philippine Institute of Volcanology and Seismology (Philippines)

RSAM - Real-time Seismic Amplitude Measurement

RVO - Rabaul Volcano Observatory

SERNAGEOMIN - Servicio Nacional de Geologia y Mineria (Chile)

SIGMET - Significant Meteorological Information

SNET - Servicio Nacional de Estudios Territoriales (El Salvador)

SVERT - Sakhalin Volcanic Eruption Response Team (Russia)

USAID - US Agency for International Development

USGS - United States Geological Survey

UTC - Coordinated Universal Time

VAAC - Volcanic Ash Advisory Center

VAFTAD - Volcanic Ash Forecast Transport And Dispersion

VDAP - Volcano Disaster Assistance Program (USGS)

VHP - Volcano Hazards Program (USGS)

VRC - Volcano Research Center (Japan)

Report for Ambae
The cone in Ambae’s Lake Voui continued to produce emissions consisting of steam, volcanic gases, and ash that drifted downwind during 5-7 April, based on reports from Vanuatu Meteorology and Geo-Hazards Department (VMGD) and Wellington VAAC notices. On 5 April low-level intermittent plumes of gas and ash rose as high as 2.5 km above the crater rim and drifted W and SW. A loud explosion followed by a dark ash emission was possibly reported. Webcam images from 2100 showed incandescence above the crater and reflected in the clouds. Intermittent emissions of gas-and-steam and gas-and-ash were visible on 7 April. Plumes rose an estimated 3 km above the crater rim and drifted E. Webcam images during 0107-0730 on 7 April showed continuing ash emissions. The Alert Level remained at 2 (on a scale of 0-5) and the public was warned to stay outside of the Danger Zone, defined as a 2-km radius around the active vents in Lake Voui, and away from drainages during heavy rains.
Sources: Vanuatu Meteorology and Geohazards Department (VMGD), Wellington Volcanic Ash Advisory Center (VAAC)
Report for Bezymianny
KVERT reported an ongoing eruption at Bezymianny generally characterized by gas-and-steam emissions and occasional collapses of hot material from the flanks of the summit lava dome. A thermal anomaly over the summit persisted in satellite images during 31 March-6 April. Diffuse ash plumes drifted as far as 550 km E during 2 and 5-6 April. On 6 April volcanologists at the Kamchatka Volcanological Station (KVS) traveled to the Apakhonchich station to assess Bezymianny, take aerial photos, and install monitoring equipment. They observed frequent collapses of the crater rim and ash plumes that drifted NE towards Apakhonchich.

KVERT stated that at 1326 local time on 7 April a satellite image showed an ash plume drifting 150 km E at altitudes of 5.5-6 km (18,000-19,700 ft) a.s.l. A satellite image from 1600 local time that same day showed an ash plume extending as far as 230 km ESE. KVERT noted that ash emissions were intensifying, likely caused by hot avalanches from a growing lava dome. The Aviation Color Code was raised to Red (the highest level on a four-color scale). On 7 April KVS volcanologists traveled to Ambon to collect ash. They reported that a notable eruption began at 1730 local time, and within 20 minutes a large ash plume had risen to 10 km and drifted NW. KVERT reported that the strong explosive phase began at 1738 local time. Based on webcam and satellite data ash plumes rose 10-12 km (32,800-39,400 ft) a.s.l. and drifted SE. Explosions were clearly audible at 20 km distance and were heard for 90 minutes, according to KVS.

Significant amounts of ash fell at the Apakhonchich station, and the snow turned gray. The volcanologists had returned to KVS by the evening, and they were covered in ash. Ashfall continued until the morning of 8 April. In a Volcano Observatory Notice for Aviation (VONA) issued at a 0906 on 8 April, KVERT stated that the strong eruptive phase was over, and the Aviation Color Code was lowered to Orange. Ash plumes had drifted about 2,000 km E. The KVS team saw a lava flow on the active dome once the conditions were clear.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Kamchatka Volcanological Station
Report for Nevado del Ruiz
Servicio Geológico Colombiano’s (SGC) reported that the number of daily events detected by the seismic network at Nevado del Ruiz fluctuated during 3-8 April but declined overall. Earthquakes were generally located 2-5 km SW of Arenas Crater at depths of 3-4 km. On 9 April SGC noted that daily counts of events were no longer going to be posted in their daily reports and instead the focus will be on the location of the earthquakes. Gas emissions had also decreased in density. That same day Gestión del Riesgo de Desastres (UNGRD) reported that 2,000-2,500 families had been identified as living in high-risk areas and requested that local authorities expedite a preventive evacuation; families that had evacuated were staying with family and friends and not in evacuation shelters.

During 3-11 April the earthquakes were associated with daily emissions of gas-and-steam and gas-and-ash plumes. Ash-and-gas plumes rose as high as 1.5 km above the crater rim on 3 April and drifted NW and SW. During 6-7 April several pulsating ash emissions were observed in webcam images and by residents of La Cabaña (Murillo, Tolima). The emissions rose as high as 1.5 km and drifted SE and NE. Webcam images and La Cabaña residents again saw ash emissions on 10 April, rising as high as 1.8 km and drifting E and NE. Thermal anomalies from Arenas Crater were periodically visible through the week. The Alert Level was remained at Orange, Level II (the second highest level on a four-level scale).
Sources: Servicio Geológico Colombiano (SGC), Gestión del Riesgo de Desastres (UNGRD)
Report for Sheveluch
On 28 March the Kamchatka Volcanological Station (KVS) reported that activity had increased at Sheveluch during the previous few days. Incandescence at the summit of the lava dome was constant and the focus of activity shifted from the E side to the NE side. KVERT reported that the ongoing eruption was generally characterized by explosions, hot avalanches, lava-dome extrusion, and strong fumarolic activity. A daily thermal anomaly was identified in satellite images during 30 March-6 April. Satellite images showed an ash plume drifting 250 km E and SE.

Seismic data around 0054 local time on 11 April indicated a significant increase in activity, as reported by the Institute of Volcanology and Seismology, Far Eastern Branch, Russian Academy of Sciences (IVS FEB RAS). According to the Tokyo VAAC the ash plume had risen to 15.8 km (52,000 ft) a.s.l. by 0110 and was drifting NW. By 0158 the plume extended over a 75 x 100 km area. KVS reported that significant pulses of activity occurred at around 0200, 0320, and then a stronger phase started around 0600. Video of the rising plume was taken at around 0600 from near Békés (3 km away) by Levin Dmitry, who reported that a pyroclastic flow traveled across the road behind him as he left the area. Ashfall began in Klyuchi (45 km SW) at 0630, and the large black ash plume had blocked the daylight by 0700. At 0729 KVERT issued a Volcano Observatory Notice for Aviation (VONA) raising the Aviation Color Code to Red (the highest level on a four-color scale). They stated that a large ash plume had risen to 10 km (32,800 ft) a.s.l. and drifted 100 km W. According to IVS FEB RAS the cloud was 200 km long and 76 km wide by 0830, and was spreading W at altitudes of 6-12 km (19,700-39,400 ft) a.s.l.

KVS reported that at about 0930 the plume drifted over Kozyrevsk (112 km SW) and turned the day to night. Almost constant lightning strikes in the plume were visible and sounds like thunderclaps were heard until about 1000. The sky lightened up in Kozyrevsk at about 1030; residents in Klyuchi reported continuing darkness and ashfall at 1100. As the day went on the light had a reddish-brown hue due to the ash in the atmosphere. In some areas ashfall was 6 cm deep and some residents reported dirty water coming from their plumbing. At 1150 an ash cloud 400 km long and 250 km wide was spreading W at altitudes of 5-20 km (16,400-65,600 ft) a.s.l., according to IVS FEB RAS. KVERT issued a VONA at 1155 noting that ash had risen to 10 km and that it had extended 340 km NNW and 240 km WSW. According to Simon Carn about 0.2 Tg of sulfur dioxide in the plume was measured in a satellite image acquired at 1343. A satellite image at 1748 showed ash plumes rising to 8 km (26,200 ft) a.s.l. and drifting 430 km WSW and S, based on a VONA. Residents of Klyuchi measured ashfall as thick as 8.5 cm, according to the Kamchatka Branch of Geophysical Services (KBGS; Russian Academy of Sciences). In a VONA issued at 0748 on 12 April KVERT stated that strong explosions were continuing. Ash plumes from explosions rose to 8 km and drifted ESE. The larger ash cloud continued to drift and had extended 600 km SW and 1,050 km ESE. IVS FEB RAS scientists photographed the terminal part of a pyroclastic flow that had traveled 19 km SSE the day before, which had stopped a few hundred meters from a bridge on the road between Kliuchi and Petropavlovsk-Kamchatsky.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Simon Carn, Kamchatka Volcanological Station, Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Aira
JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 3-10 April, with crater incandescence visible nightly. Very small eruptive events occasionally occurred. Sulfur dioxide emissions were high at 2,700 tons per day on 4 March. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.
Source: Japan Meteorological Agency (JMA)
Report for Cotopaxi
IG reported that eruptive activity at Cotopaxi was ongoing during 4-11 April. Gas, steam, and ash plumes visible in webcam images and reported by the Washington VAAC during 4-6 and 8 April rose 200-800 m above the summit and drifted E, SE, S, and SW. Minor ashfall was reported in Mulaló (9.5 km WSW) and San Agustín (10 km W). Gas-and-steam plumes rose 300 m and drifted S and SE on 7 April. On 10 April ash plumes rose 1-1.5 km and drifted W, SW, and SE. Weather clouds prevented visual observations on the other days. Servicio Nacional de Gestión de Riesgos y Emergencias (SNGRE) maintained the Alert Level at Yellow (the second lowest level on a four-color scale).
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN), Servicio Nacional de Gestión de Riesgos y Emergencias (SNGRE)
Report for Ebeko
KVERT reported that moderate activity at Ebeko was ongoing during 30 March-6 April and a daily thermal anomaly was identified in satellite images. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions during the week generated ash plumes that rose as high as 4 km (13,100 ft) a.s.l. and drifted in various directions. Ash plumes drifted 12 km E and SW on 3 and 6 April. The Aviation Color Code remained at Orange (the second highest 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 Fuego
INSIVUMEH reported that 4-12 explosions per hour were generally recorded at Fuego during 4-11 April, generating ash plumes that rose as high as 1.1 km above the crater rim and drifted as far as 20 km W, SW, and S. Weather clouds sometimes prevented views. Daily ashfall was recorded in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), La Rochela, San Andrés Osuna, Siquinala, Ceylon, Finca La Asunción, and Finca Palo Verde. Daily block avalanches descended multiple drainages including the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, Las Lajas (SE), and El Jute (ESE), and often reached vegetated areas. Daily shock waves rattled structures in communities around the volcano and rumbling was often heard. Explosions ejected incandescent material as high as 350 m above the summit each day.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Great Sitkin
AVO reported that lava likely continued to slowly effuse at the summit of Great Sitkin during 5-11 April, producing a thick lava flow. Seismicity was low, and during 9-10 April only a few events were detected. A satellite radar image on 2 April showed that the lava flow was mostly expanding to the E and slowly to the S into the summit crater ice field. Elevated surface temperatures were identified in satellite images during 4-6 April. Weather clouds obscured views during 7-10 April. The Volcano Alert Level remained at Watch (the second highest level on a four-level scale) and the Aviation Color Code remained at Orange (the second highest color on a four-color scale).
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Karangetang
Webcam images of Karangetang captured in the PVMBG daily reports periodically showed small areas of incandescence at the summit Main Crater (S crater) and on the flanks during 4-10 April. The Alert Level remained at 3 (on a scale of 1-4) and the public were advised to stay 2.5 km away from Main Crater with an extension to 3.5 km on the S and SE flanks.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Katmai
AVO reported that on 8 April strong winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes blew unconsolidated ash SE across Shelikof Strait to Kodiak Island at an altitude up to 2.4 km 8,000 ft) a.s.l. The ash was originally deposited during the Novarupta eruption in 1912. 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 level on a four-color scale).
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Krakatau
PVMBG reported that daily white steam-and-gas plumes rose as high as 200 m above Anak Krakatau’s summit during 5-11 April. White-and-black plumes rose as high as 300 m above the summit and drifted NE on 9 April. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay at least 5 km away from the crater.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Lascar
SERNAGEOMIN reported that during the last two months activity at Láscar had declined to low levels, based on seismological, geodetic, geochemical, and remote sensing data, though remained above baseline. The volume of the lava dome remained unchanged, seismicity was low including small numbers of volcano-tectonic and tornillo-type events, sulfur dioxide gas emissions were low, and tephra was absent from emissions. On 6 April the Alert Level was lowered to Yellow (the second lowest level on a four-color scale) and the public was warned to stay at least 5 km away from the crater. SENAPRED updated the Alert Level Yellow (the middle level on a three-color scale) for San Pedro de Atacama (70 km NW) and maintained a security perimeter of 10 km around the volcano.
Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN), Sistema y Servicio Nacional de Prevención y Repuesta Ante Desastres (SENAPRED)
Report for Lewotolok
PVMBG reported that the eruption at Lewotolok was ongoing during 5-11 April. White steam-and-gas plumes were seen on most days rising as high as 500 m above the summit and drifting in multiple directions. According to the Darwin VAAC an ash plume rose to 1.8 km (6,000 ft) a.s.l., or about 370 m above the summit, on 6 April and drifted N. On 7 April white-and-gray plumes of variable densities rose 100-400 m and drifted SE and W; similar plumes on 9 April rose 200-350 m and drifted NE and E. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 2 km away from the summit crater.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Merapi
BPPTKG reported that the eruption at Merapi (on Java) continued during 31 March-6 April and seismicity remained at high levels. The SW lava dome produced 79 lava avalanches that traveled as far as 1.8 km down the SW flank (upstream in the Bebeng and Boyong drainages). One pyroclastic flow traveled 1.1 km down the SW flank, upstream of the Bebeng drainage. Morphological changes to the SW lava dome were evident in webcam images due to continuing 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 Nishinoshima
JMA reported that at 1050 and 1420 on 11 April ash plumes from Nishinoshima rose 1.9 km above the crater rim and drifted NW and W [Correction: NW and N.]
Source: Japan Meteorological Agency (JMA)
Report for Santa Maria
INSIVUMEH reported that the eruption at Santa María’s Santiaguito lava-dome complex continued during 4-11 April. Daily explosions produced gas, steam, ash plumes that rose as high as 1 km above the complex and drifted sometimes as far as 8 km W, SW, and S; during 8-9 April the plumes drifted W and rose as high as 1.8 km. Rumbling was barely audible on nearby farms during 8-9 April. Effusion from Caliente dome fed lava flows that slowly descended the San Isidro and Zanjón Seco drainages on the W and SW flanks. Incandescence from the dome and the lava flows was visible nightly and some early mornings. Block avalanches from the dome, and from both the ends and sides of the flows, descended the S, SW, and W flanks were reported almost daily. Residents were reminded to stay at least 6 km away from the complex.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Semeru
PVMBG reported that the eruption at Semeru continued during 5-11 April and a few Volcano Observatory Notices for Aviation (VONAs) were issued through the week. At 0559 on 8 April a dense white-to-brown plume rose 800 m above the summit and drifted NE. About an hour and a half later, at 0732, a white-to-gray plume rose 600 m and drifted N. At 0635 and 2218 on 10 April variable white-and-gray plumes rose 500-800 m and drifted N and NE. At 0535 on 11 April a dense white-and-gray plume rose 500 m and drifted N. The Alert Level remained at 3 (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, 100 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages originating on Semeru, including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Semisopochnoi
AVO reported that low-level unrest continued at Semisopochnoi during 5-11 April. An extensive low-altitude steam plume drifted more than 400 km during 4-6 April and was likely related to volcanic emissions but did not appear to contain ash. Several small explosions were detected on 5 April, and periods of seismic tremor and local earthquakes were recorded during 5-6 April, but seismicity was quiet during the rest of the week. Clouds obscured webcam and satellite views during 7-10 April. The Volcano Alert Level remained at Watch (the second highest level on a four-level scale) and the Aviation Color Code remained at Orange (the second highest color on a four-color scale).
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Suwanosejima
JMA reported that the eruption at Suwanosejima's Ontake Crater continued during 3-10 April. Eruptive activity produced ash plumes that rose as high as 1.6 km above the crater rim and drifted mainly SE, E, and N. Large blocks were ejected as far as 300 m from the vent. Crater incandescence was visible at night during 3-7 April and one explosion was detected during 7-10 April. The Alert Level remained at 3 (on a 5-level scale) and residents were warned to stay 2 km away from the crater.
Source: Japan Meteorological Agency (JMA)