Logo link to homepage

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 29 December-4 January 2011
Name Location Eruption Start Date Report Status
Etna Sicily (Italy) 2022 Nov 27 New
Kizimen Eastern Kamchatka (Russia) New
Manam Northeast of New Guinea 2014 Jun 29 New
Stromboli Aeolian Islands (Italy) 1934 Feb 2 New
Aira Kyushu (Japan) 2017 Mar 25 Continuing
Bezymianny Central Kamchatka (Russia) 2016 Dec 5 Continuing
Bulusan Luzon (Philippines) Continuing
Fuego South-Central Guatemala 2002 Jan 4 Continuing
Gaua Banks Islands (Vanuatu) Continuing
Karymsky Eastern Kamchatka (Russia) Continuing
Kilauea Hawaiian Islands (USA) Continuing
Machin Colombia Continuing
Santa Maria Southwestern Guatemala 1922 Jun 22 Continuing
Sheveluch Central Kamchatka (Russia) 1999 Aug 15 Continuing
Soufriere Hills Montserrat Continuing
Suwanosejima Ryukyu Islands (Japan) 2004 Oct 23 Continuing
Tengger Caldera Eastern Java Continuing
Tungurahua Ecuador Continuing
All times are local unless otherwise stated.
Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 19,934 individual reports over 1,212 weeks (average of 16 per week) on 332 different volcanoes.

Search by Date



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

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



Search by Volcano



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


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.



Download Smithsonian / USGS Weekly Volcanic Activity Report Network CAP Feed

The CAP (Common Alerting Protocol) feeds are XML files specifically formatted for disaster management. They are similar in content to the RSS feed, but contain no active links.



Download Smithsonian/USGS Weekly Volcanic Activity Report Network Link Download Smithsonian / USGS Weekly Volcanic Activity Report Network Link

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 Etna
INGV-CT reported that during the first few days of December gas emissions from a large pit crater on the lower E flank of Etna's Southeast Crater cone nearly ceased. On 22 December at 0446 a strong explosion occurred at the W vent of the Bocca Nuova (BN-1). This event generated an ash plume a few meters high, which then drifted NE, causing light ashfall in areas as far as the town of Linguaglossa (17 km NE). On 23 December bluish gas rose from a vent at the base of the W wall of the pit, at the base of the Southeast Crater cone. Bright incandescence was intermittently visible on video footage. Inclement weather prevented clear observations that day and during the next few days. On 29 December extremely small amounts of incandescent material emitted from the pit crater were observed using visible and thermal cameras. The brief emissions (2-6 second intervals) were jets of mainly hot gas that barely rose above the rim of the pit crater. Inclement weather again prevented observations of the crater during 30-31 December.

During the late afternoon on 2 January, strong incandescence at the pit crater evolved into vigorous Strombolian activity. Frequent Strombolian explosions (1-3 per minute) ejected coarse-grained incandescent material a few tens of meters above the rim of the pit. On a few occasions, incandescent bombs fell outside the pit's rim, mainly to the S and E. The activity continued into the early morning then decreased markedly. Negligible quantities of volcanic ash were produced.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Kizimen
KVERT reported that a thermal anomaly over Kizimen's lava dome was observed in satellite imagery during 29 December-1 January and that an explosive eruption that began on 13 December continued. On 31 December seismicity increased and volcanic tremor was detected. Explosions occurred sporadically for a period of about 20 minutes. Ash plumes detected in satellite imagery rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted SW. Ashfall at least 1 mm thick occurred in multiple areas 225-275 km SSW, including Petropavlovsk-Kamchatsky, Yelizovo, Paratunka, and Nalychevo. On 1 January the Aviation Color Code was raised to Red. Ash plumes at an altitude of 4 km (13,100 ft) a.s.l. drifted 480-500 km SW; ash continued to accumulate in some areas. Seismic data indicated increased activity on 3 January. Explosions continued, and ash plumes drifted more than 200 km SE. A large and bright thermal anomaly was observed in satellite imagery.

Based on analysis of satellite imagery, the Tokyo VAAC reported that possible eruptions during 2-4 January produced plumes that rose to an altitude of 3-4.6 km (10,000-15,000 ft) a.s.l. and drifted S, E, and NE. Subsequent images on those same days showed ash emissions continuing, then dissipating.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Manam
RVO reported that on 25 December a new episode of eruptive activity from Manam's South Crater began and was characterized during 25-29 December by rising ash plumes and ejections of incandescent lava fragments. Although most of the material fell back into the crater, some was deposited around the summit area, and some larger fragments were deposited in the SW and SE valleys. The Main Crater produced white plumes occasionally laden with ash. Incandescence was visible on some nights.

On 30 December activity from South Crater increased and was reported by observers in Bogia, 20 km SSW, on the mainland. A dense ash plume rose 3 km above the summit crater and drifted NW. An observer at Tabele on the SW flank confirmed the eruption and also reported that three pyroclastic flows descended the SE valley, stopping by a few to several hundred meters from the coastline. The first and largest pyroclastic flow devastated a broad unpopulated area between Warisi and Dugulava villages. Ash plumes drifted NW and caused light ashfall in Tabele. RVO recommended an increase in the Alert Level to Stage 3. Later that day, ash emissions and incandescent fragment ejections diminished.

On 31 December, gray ash plumes rose 200-300 m above the South Crater and also above the Main Crater. Low booming sounds were noted and incandescence from the crater was observed at night. During 1-4 January eruptive activity continued from South Crater and gray-to-black ash plumes rose above the summit crater. Incandescence emanated from the crater. During 3-4 January incandescent fragments were ejected onto the flanks and rolled down the SE valley. White vapor rose from the Main Crater.
Source: Rabaul Volcano Observatory (RVO)
Report for Stromboli
INGV-CT reported that on 19 December a major explosion from a vent in the southern part of Stromboli's crater terrace occurred at 0956, coincident with explosive sequence consisting of three discrete seismic events. During the last few days of December the "S1" vent produced frequent explosions of greater intensity than those of the preceding days. Jets rose 200 m above the crater terrace. On 27 December, the frequency of the explosions rose to 11-14 per hour. The "S1" vent is immediately next to the "S" vent, the source of the 19 December explosion.
Source: Sezione di Catania - Osservatorio Etneo (INGV)
Report for Aira
Based on information from JMA, the Tokyo VAAC reported that on 2 January a plume from Sakura-jima rose to an altitude of 1.8 km (6,000 ft) a.s.l. An explosion was noted the next day. An explosion on 5 January produced a plume that rose to an altitude of 1.2 km (4,000 ft) a.s.l. and drifted E.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Bezymianny
KVERT reported that during 24-30 December seismicity did not exceed background levels. The temperature of thermal anomalies observed in satellite imagery during 23-24 and 27-28 December gradually increased. Gas-and-steam emissions were seen on 27 and 28 December; clouds prevented observations on the other days. The Aviation Color Code level remained at Yellow.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Bulusan
Based on notices from the Manila airport (RPLL), the Tokyo VAAC reported that on 29 and 30 December ash from Bulusan was observed. PHIVOLCS noted that inclement weather prevented views of the summit area during 29-31 December. Eight volcano-tectonic earthquakes were detected by the seismic network during 30-31 December.
Sources: Philippine Institute of Volcanology and Seismology (PHIVOLCS), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Fuego
INSIVUMEH reported that during 29-30 December explosions from Fuego, almost constant at times, produced dense ash plumes that rose 600-800 m above the crater and drifted 8 km W and SW. Avalanches occurred on the flanks. The Washington VAAC reported that several small emissions observed in satellite imagery drifted W on 1 January. INSIVUMEH noted that during 3-4 January explosions generated ash plumes that rose 800-1,000 m above the crater and fanned out towards the S and SW. The plumes drifted almost 15 km and caused ashfall in areas downwind, including Panimaché (6 km SW), Morelia (7 km SW), and Santa Sofia (12 km SW). Incandescence from the crater was observed at night.
Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Gaua
On 21 December, the Vanuatu Geohazards Observatory reported that volcanic activity from Gaua had been low since September. Recent observations indicated that the near-vent vegetation and vegetation exposed to trade winds on the W side of the island was again growing. Seismic data showed a decreasing number of events. The Alert Level was lowered to 1 (on a scale of 0-4).
Source: Vanuatu Meteorology and Geohazards Department (VMGD)
Report for Karymsky
KVERT reported that seismic activity at Karymsky was above background levels during 23-26 December and did not exceed background levels during 27-30 December. Seismic data suggested that possible ash plumes rose to an altitude of 4.3 km (14,100 ft) a.s.l. Thermal anomalies were detected in satellite imagery during 23-24 December; cloud cover prevented views on the other days. The Aviation Color Code level remained at Orange.

Based on a Yelizovo Airport (UHPP) notification, the Tokyo VAAC reported that on 31 December an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted E.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Kilauea
During 29 December-4 January, HVO reported that activity at Kilauea continued from the summit caldera and the east rift zone. At the summit caldera, the level of the lava-pool surface in the deep pit within Halema'uma'u crater circulated and remained mostly stable at approximately 120 m below the crater floor, periodically rising several meters higher. Nighttime incandescence was visible from the Jaggar Museum on the NW caldera rim. A plume from the vent that drifted mainly SW deposited ash and fresh spatter nearby.

At the east rift zone, lava that broke out of the Quarry tube onto the surface, at a saddle between two rootless shields at around the 610 m elevation, continued to advance in two branches. The lava flow at the lowest elevation advanced E beyond Kalapana by 3 January. Incandescence from a small spatter cone on the north-central part of Pu'u 'O'o crater floor continued. Lava from that cone flowed SE, NE, and W. Lava from a second spatter cone, located on the NW edge of the crater, was active on the crater floor. Weak incandescence was also visible from a small, fume-producing vent in the E wall of the crater, and from other various areas on the crater floor.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Report for Machin
According to INGEOMINAS, Observatory Vulcanológico and Sismológico de Manizales reported a period of increased seismicity from Cerro Machín on 31 December. A total of 346 volcano-tectonic events no stronger than M 2.1 were located S and SW of the main lava dome. On 1 January seismicity again increased, and at the time of the report, 367 events had been detected. The low-magnitude events were located S and SW of the main dome at depths between 2.5 and 4.5 km. The largest event, M 2.3, was located S of the dome at a depth of about 3.3 km and felt by residents near the volcano and in the municipality of Cajamarca, 14 km WSW. The Alert level remained at III (Yellow; "changes in the behavior of volcanic activity").
Source: Servicio Geológico Colombiano (SGC)
Report for Santa Maria
INSIVUMEH reported that during 29-30 December a few explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose 300-600 m above Caliente dome and drifted S and SE. Ashfall was reported in local villages downwind. The Washington VAAC reported that several small emissions observed in satellite imagery drifted W on 1 January. During 3-4 January, INSIVUMEH reported that explosions produced ash plumes that rose 700 m above the complex and drifted SW. Avalanches descended the W part of the dome.
Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Report for Sheveluch
KVERT reported that moderate seismic activity from Shiveluch was detected during 24-30 December. Ash explosions on 24 December produced ash plumes that rose to altitudes as high as 4.5 km (14,800 ft) a.s.l. A bright thermal anomaly over the volcano was observed in satellite imagery during 24 and 27-28 December. Moderate gas-and-steam activity was visually observed on 24 and 28 December. The Aviation Color Code level remained at Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Report for Soufriere Hills
MVO reported that during 24-31 December activity from the Soufrière Hills lava dome was at a low level. Rockfalls or small pyroclastic flows detected by the seismic network occurred in the 11 February collapse scar on the N side of the volcano. Clouds prevented clear views of the lava dome. Lahars associated with heavy rains descended multiple drainages on 30 December. The Hazard Level remained at 3.
Source: Montserrat Volcano Observatory (MVO)
Report for Suwanosejima
Based on information from JMA, the Tokyo VAAC reported an explosion from Suwanose-jima on 29 December. Details of a possible resulting plume were not reported.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
Report for Tengger Caldera
Based on analyses of satellite imagery, the Darwin VAAC reported that on 30 December an ash plume from Tengger Caldera's Bromo cone rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted about 95 km E.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
Report for Tungurahua
Although storm clouds occasionally prevented observations of the summit area, IG reported that steam plumes were observed almost daily during 29 December-4 January. Incandescence from the crater was occasionally observed at night. On 30 December a steam-and ash plume rose 500 m above the crater and drifted W. On 2 January a small explosion produced an ash plume that also rose 500 m above the crater and drifted W.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)