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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 1 December-7 December 2021
Name Location Eruption Start Date Report Status
Ambae Vanuatu 2021 Dec 5 New
Nyiragongo DR Congo 2002 May 17 (?) New
Sangay Ecuador 2019 Mar 26 New
Semeru Eastern Java 2014 Apr 1 ± 15 days New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Etna Sicily (Italy) 2013 Sep 3 Continuing
Fuego South-Central Guatemala 2002 Jan 4 Continuing
Great Sitkin Andreanof Islands (USA) 2021 May 25 Continuing
Grimsvotn Iceland Continuing
Karymsky Eastern Kamchatka (Russia) 2020 Apr 1 Continuing
Kilauea Hawaiian Islands (USA) 2021 Sep 29 Continuing
La Palma Canary Islands Continuing
Lewotolok Lembata Island 2020 Nov 27 Continuing
Merapi Central Java 2020 Dec 31 Continuing
Pavlof Alaska Peninsula, Alaska 2021 Aug 5 Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
Semisopochnoi Aleutian Islands (USA) 2021 Feb 2 ± 2 days Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 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 17,900 individual reports over 1,120 weeks (average of 16 per week) on 321 different volcanoes.

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Use the dropdowns to choose the year and week for archived Weekly Reports.

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


Download Smithsonian / USGS Weekly Volcanic Activity Report Network RSS Feed

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 Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that steam emissions were visible rising an average of 250 m from Ambae’s Lake Voui during 5-7 December. A still image of video taken from an airplane showed brown water surrounding an active and growing cone that was ejecting wet tephra less than 10 m above the lake’s surface. The Alert Level remained at 1 (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 2017-2018 active vents in Lake Voui and away from drainages during heavy rains.
Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD)
Report for Nyiragongo
According to a news article seismic signals at Nyiragongo were dominated by long-period earthquakes during 30 November-5 December. Residents of Goma observed incandescence emanating from the crater on 4 December.
Source: Les Volcans News
Report for Sangay
IG reported that during 1-2 December activity at Sangay was characterized by increased seismicity, explosions and ash emissions, and a new lava flow on the N flank. The SAGA seismic station, SW of the volcano, recorded a swarm of long-period events beginning at 1600 on 1 December that indicated fluid movements. The amplitude and frequency of the events intensified, and by 2356 the rate had increased from 32 to 60 events per hour. At 0403 on 2 December the SAGA station recorded a major explosion. Based on Washington VAAC advisories two eruption plumes rose 7-10 km above the summit and drifted W, and a third rose almost 1.8 km and drifted NW, though IG noted that the lack of reported ashfall in the nearest towns 25 km away indicated low ash content. Thermal satellite data showed that a new lava flow had emerged on the upper N flank by 2 December.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
Report for Semeru
PMVBG reported collapses of the lava dome in Semeru’s Jonggring Seloko Crater and SE-flank flow during 1-6 December. On 1 December material collapsed from the unstable distal end of a 1-km-long lava flow in the SE-flank Kobokan drainage, sending a pyroclastic flow 700 m down the valley. Subsequent avalanches were recorded by the seismic network that day and on 3 December were not visually confirmed, likely due to several days of rainy conditions. At 1330 on 4 December the seismic network recorded avalanche signals. A larger collapse began at 1447 was seen by an observer at the Mount Semeru Volcano Observation Post and identified in data collected by PVMBG. Avalanches of incandescent material from the summit dome and SE-flank lava flow descended 500-800 m. Pyroclastic flows were visible at 1510 descending the Kobokan drainage and a sulfur odor was noted. At 1520 a large pyroclastic flow produced a large roiling and expanding ash cloud that eventually rose to 15 km (50,000 ft) a.s.l. Reports from residents described darkness from airborne ash and rainy/foggy conditions. Pyroclastic material was deposited in two districts in the Lumajang regency, and eight districts in the neighboring Malang regency were covered with ash. Preliminary estimates suggested that deposits extended at least 16 km SE from the summit.

According to the Darwin VAAC satellite observations acquired at 1630 showed a detached ash cloud drifting SW at an altitude of 15 km (50,000 ft) a.s.l. At 1740 the ash cloud continued to drift SW and a second ash cloud was drifting W at 9.1 km (30,000 ft) a.s.l. The second ash cloud had detached by 1840. On 5 December satellite images showed the two ash clouds still drifting SW and W, and possible diffuse ash emissions rising to 4.6 km (15,000 ft) a.s.l.; ash had dissipated by 1000.

Following the 4 December pyroclastic flow Badan Penanggulangan Bencana Daerah (BPBD) issued a warning to residents to stay away from drainages due to lahar hazards and began evacuating people in high-risk areas. Ten people trapped in a building could not be reached because of scalding hot deposits but were later rescued. Almost all of the houses in the Curah Kobokan area had been destroyed, mainly by pyroclastic flows, though some residents reported roof collapses from ashfall. One area of Curah Kobokan was inundated by hot lahars that took down trees. Pyroclastic flows also destroyed the Gladak Perak bridge, 13 km SE of the summit, which linked residents of Pronojiwo and Lumajang; the national road leading to Malang was blocked by tephra and fallen trees. According to news articles and BNPB, by the next day 14 people were confirmed to have died, 57 had been injured and taken to hospitals (more than a dozen of were in critical condition due to severe burns), and at least seven residents and sand miners working along the river in Curah Kobokan were missing. About 1,300 people had relocated to evacuation centers or alternative housing.

Additional pyroclastic flows during 5-6 December descended 2-3 km SE, and incandescent avalanches descended 500 m. At 0855 on 6 December a pyroclastic flow traveled 4 km down the SE drainage, temporarily halting rescue and recovery efforts. Later that day, the head of BNPB, police officers, and others conducted a 15-minute overflight of Curah Kobokan and observed steam plumes rising from the deposits. Initial estimates were that 2,970 houses and 38 educational facilities across several sub-districts in Lumajang Regency had been destroyed or damaged by the pyroclastic flows. Authorities also traveled to the fallen bridge and other nearby locations, noting damaged vegetation, fallen trees, and volcanic deposits up to 30 cm thick along the road.

By 7 December an estimated 4,250 residents were displaced in about 20 evacuation centers; most people originating from the Lumajang Regency and fewer from the Malang and Blitar regencies. The number of fatalities reached 34, with another 22 people missing. Search efforts focused on the villages of Renteng, Sumberwuluh, and Kobokan Curah, but daily afternoon rains hampered rescue and recovery efforts.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Badan Nacional Penanggulangan Bencana (BNPB), National Public Radio (NPR), BBC News, Earth Observatory of Singapore, Remote Sensing Lab
Report for Aira
JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 29 November-6 December. An eruptive event at 1702 on 2 December generated a plume that rose 1.3 km above the crater rim. 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)
Report for Etna
INGV reported that during 29 November-5 December eruptive activity at Etna was concentrated at the Northeast Crater (NEC) and the Southeast Crater (SEC), while only minor gas emissions rose from the Voragine and Bocca Nuova craters. Webcam images showed diffuse and discontinuous ash emissions from NEC on 1 December that quickly dissipated near the summit. On the morning of 4 December INGV staff working near the summit observed sporadic and diffuse ash emissions rising from SEC and quickly dissipating around the summit. During the afternoon and through the next day webcam images recorded Strombolian activity at SEC, in addition to the ash emissions.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Fuego
INSIVUMEH reported that 3-12 explosions per hour were recorded at Fuego during 30 November-7 December, generating ash plumes as high as 1 km above the crater rim and periodic shock waves that were felt in communities around the volcano. Ash plumes drifted as far as 25 km SW and W, causing almost daily ashfall 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), and San Pedro Yepocapa (8 km NW). Block avalanches descended the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Las Lajas (SE), and El Jute drainages, often reaching vegetated areas. Explosions ejected incandescent material up to 100-200 m above the summit during 30 November-3 December. A new lava flow emerged during the morning of 5 December and lengthened to 400 m by the next day. During 5-6 December explosions ejected incandescent material 100 m above the summit.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Great Sitkin
AVO reported that slow lava effusion at Great Sitkin likely continued during 1-7 December. Elevated surface temperatures at the summit were periodically detected through the week. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Grimsvotn
The Icelandic Meteorological Office (IMO) reported that the jökulhlaup (glacial outburst flood) due to subsidence of the ice shelf in Grímsvötn’s caldera continued until 6 December. Subsidence of the ice shelf into the underlying lake had begun around 24 November in an area SE of Grímsfjall. Water from the lake drained from the E side of Skeiðarárjökull and from a channel in the middle of a trail into the Gígjukvísl River, causing rising waters first detected in that river overnight during 30 November-1 December. By 2 December the flow rate in the river was 930 meters per second, triple what was detected three days before, and 10 times the normal seasonal rate. Daily measurements showed that the flow rate continued to rise, likely peaking at 2,800 meters per second during the morning of 5 December; a second measurement later that day showed a lower discharge rate of 2,310 meters per second. The ice shelf continued to subside, though more slowly, and water turbulence in the lake had also decreased; the data indicated that the lake was mostly empty of water. A number of detected earthquakes were attributed to subsiding and breaking ice.

By 6 December the ice shelf had subsided a total of about 77 m. At 0615 an M 2.3 earthquake was immediately followed by a M 3.6 one minute later. Five more earthquakes were recorded during 1500-2130, though all were below M 1. IMO raised the Aviation Color Code to Orange (the second highest level on a four-color scale) based on the increased seismicity during the previous few days, the larger events that morning, and considerations such as short run-up times seen before previous eruptions, and those past eruptions occasionally following flood events. Seismic tremor had decreased by the next day, and no signs of eruptive activity were indicated in gas or deformation data. On 7 December the Aviation Color Code was lowered to Yellow.
Source: Icelandic Meteorological Office (IMO)
Report for Karymsky
KVERT reported that on 25 November explosions at Karymsky generated ash plumes that rose as high as 6 km (19,700 ft) a.s.l. and drifted 30 km NW. A thermal anomaly was visible in satellite images during27-29 November. Explosions on 2 December produced ash plumes that rose up to 4 km (13,100 ft) a.s.l. and drifted 100 km ENE. Dates are based on UTC times. 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 Kilauea
HVO reported that lava effusion continued at a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 1-2 December. The rate of effusion sharply decreased, along with volcanic tremor levels, during 1600-1800 on 3 December. A small part of the vent cone collapsed at around 1700. No surface activity was observed on 5 December and most of the next day though weather conditions hindered visual confirmation; a few small hotspots around the vent were visible in thermal camera images. Lava was visible in the vent at about 1730 on 6 December and within 30 minutes was flowing into the lake. By 0300 on 7 December lava had covered the prior extent of the lava lake. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for La Palma
The eruption at La Palma continued during 1-7 December, characterized by Strombolian explosions and lava fountaining/jetting from multiple existing and new vents, advancing and sometimes branching lava flows, and almost daily ash emissions. Seismicity persisted at variable but elevated levels, with earthquake locations distributed at depths of 10-15 km and 30-40 km. Seismicity was intense at both levels during 30 November-2 December, though the intensity at deeper levels began to wane; in general, earthquake activity was low by the end of the week. Volcanic tremor levels fluctuated at medium to intense levels early in the week but by 3 December were also at low levels.

Several vents in the main cone continued to effuse lava, eject tephra, and emit ash-and-gas plumes. Lava moved W through pre-existing lava channels, lava tubes, over older flows, and over new ground, increasing the flow field that consists of overlapping flows (numbered 1-12) and two lava deltas. Persistent Strombolian activity was sometimes intense at the NE-flank vent during 1-3 December, and lava continued to feed flow 8 and the N delta. Lava fountains rose 400-500 m above the vent on 2 December. A new pyroclastic cone had formed around the vent, though it was unstable, and blocks from collapses of parts of it were transported downslope by lava flows. The northernmost flow, flow 12, traveled over new ground in the Fronton area and then rejoined flow 8 downslope. The flows reached part of the Tacande highway on 3 December. The vents in the main cone were quieter, periodically emitting ash and gasses. A N-S-oriented crack opened in an area 100 m S of the main vent, likely from subsidence, because it was not hot or emitting gas. The NE vent was quiet by 4 December.

On 3 December a new fissure opened on the SE of the main cone and produced Strombolian activity and fast-moving lava flows that traveled SW, along flow 10. The flow continued to advance W on 4 December, though at a slower rate as it moved over new ground in gaps between flows 3 and 11. Several new vents along an E-W fissure located W of Montaña del Cogote opened at noon on 4 December and produced multiple fast-moving lava flows. The flows descended SW over new ground, crossing into the municipalities of Tazacorte and Los Llanos de Aridane, destroying 60 homes. The flow joined flow 9, reached the sea cliff in the Las Hoyas area by 5 December, and descended the cliff the next day. During 6-7 December lava advanced W through multiple tubes and fed flows 1 and 2, and the S delta. The NE vent was quiet for a few days, but sporadic Strombolian activity and ash emissions had returned. Cracks and fractures in the upper part of the cone were visible. Several vents in the central and SE parts of the main cone also produced sporadic Strombolian activity and ash emissions. By 7 December lava had covered an estimated 11.82 square kilometers. The number of people that had evacuated and were staying in hotels had increased to 537.

Gas and ash emissions periodically impacted island residents. Suspended ash and high concentrations of volcanic gases triggered a few air-quality alerts mostly affecting the W part of the island; authorities warned residents in some areas to stay indoors. Residents and essential personnel were occasionally barred from entering the exclusion zones to irrigate crops and remove ash from streets and buildings. Ash-and-gas plumes visible during 1-3 and 6-7 December rose as high as 3.5 km a.s.l.; volcanic plumes drifted W, SW, and SSW all week, away from the airport. Daily measurements indicated that sulfur dioxide emissions persisted at “high” levels, indicating values of 1,000 to 29,999 tons per day.
Sources: Instituto Volcanológico de Canarias (INVOLCAN), Instituto Geográfico Nacional (IGN), Gobierno de Canaries
Report for Lewotolok
PVMBG reported that the eruption at Lewotolok continued during 1-7 December. Daily white-and-gray ash plumes that were sometimes dense rose as high as 800 m above the summit. Incandescent material was ejected from the vent on most days, and up to 300 m during 6-7 December, accompanied by roaring and rumbling. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Merapi
BPPTKG reported no notable morphological changes to Merapi’s summit lava dome, though the dome just below the SW rim had decreased about 2 m in height during 26 November-2 December. The estimated dome volumes were 1.61 million cubic meters for the SW dome and almost 2.95 million cubic meters for the summit dome. The intensity of the seismic signals was higher than the week before. As many as 170 lava avalanches traveled a maximum of 2 km SW. Two pyroclastic flows traveled a maximum of 3 km SW on 1 December. In a VONA (Volcano Observatory Notice for Aviation), PVMBG stated that at 2104 on 1 December an ash plume rose 1 km above the summit and drifted E. According to BPPTKG a pyroclastic flow traveled 1.8 km down the Bebeng drainage on the SW flank at 1644 on 6 December. The event lasted two minutes and 40 seconds based on seismic data. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-5 km away from the summit based on location.
Sources: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG), Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
Report for Pavlof
AVO reported that the eruption at Pavlof continued during 1-7 December, focused at a vent on the upper SE flank. Seismicity remained elevated and several daily explosions were detected using infrasound data. Elevated surface temperatures were observed in satellite data during 1-2 December, though cloud cover often prevented observations. No emissions were visible in mostly cloudy satellite and webcam views during 1-3 December. Minor ash emissions were visible in webcam images on 4 December and, based on webcam images and a pilot observation, the next day a diffuse ash plume rose as high as 3 km (10,000 ft) a.s.l. and drifted tens of kilometers beyond the volcano. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange.
Source: US Geological Survey Alaska Volcano Observatory (AVO)
Report for Santa Maria
INSIVUMEH reported that the eruption at Santa María’s Santiaguito lava-dome complex continued during 1-7 December. Avalanches generated by both lava effusion at the WSW part of Caliente dome and collapsing material descended the flanks in multiple directions, often reaching the base of the dome. Periodically the avalanches produced curtains of ash along their paths that dissipated near the volcano. Some of the avalanches were preceded by explosions detected by the seismic network and some were audible several kilometers away. During 2-3 and 6-7 December ash plumes rose 500 m above the summit and drifted 10 km NW and W, causing ashfall in areas downwind including San Marcos Palajunoj (8 km SW) and Loma Linda (6 km WSW). During 3-4 December ash-and-steam plumes rose 900 m and drifted SW and W.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Semisopochnoi
AVO reported that low-level eruptive activity and elevated seismicity at Semisopochnoi's North Cerberus crater continued during 1-7 December. Several daily explosions were detected in seismic and infrasound data. Weather clouds sometimes obscured satellite and webcam views of the volcano, though on most days low-level ash-and-steam plumes rising no higher than 1.5 km (5,000 ft) a.s.l. were visible mostly in webcam images. During 3-4 December a diffuse ash plume was identified in a satellite image drifting about 100 km E. 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 Sheveluch
KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 26 November-3 December. 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 Suwanosejima
JMA reported that during 29 November-6 December about 47 explosions at Suwanosejima's Ontake Crater produced eruption plumes that rose as high as 1.7 km above the crater rim and ejected blocks 600-700 m away from the crater. Plumes from non-explosive events rose as high has 2.3 km. Crater incandescence was visible nightly and ashfall was reported in Toshima village (4 km SSW). The Alert Level remained at 3 and the public was warned to stay 2 km away from the crater.
Source: Japan Meteorological Agency (JMA)