All times are local unless otherwise stated.

Toliman | 23 April-29 April 2003 | New Activity / Unrest Cite this Report

Toliman South-Central Guatemala

A landslide on the outer flanks of Tolimán volcano passed through and buried portions of a mountain village at 0418 on 23 April. Regional authorities blamed steep slopes, wet soils, and minor tremors. The disaster struck the village of Chichicaste, which lies along the volcanic front ~300 km W of the capital, Guatemala City. Tolimán and the area stricken sit on the S side of Lake Atitlán, the 18 x 12 km lake filling the depression of Guatemala's famous Atitlán caldera. As of the afternoon of 23 April, the Guatemalan agency CONRED reported 200 people evacuated, 20 missing, and 6 confirmed dead. Known damage to infrastructure included 40 homes at risk, another 12 with severe damage, and 6 destroyed. The village and environs had been specifically mentioned as vulnerable to landslide hazards in a government report issued in September 2002 following a similar disaster then. Mudslides in highland areas are common during the wet season, an interval that often occurs during late March through September. [Correction: the landslide recorded in April 2003 did not occur on the flanks of Toliman as erroneaously reported; instead the landslide occurred in Chim, an area about 75 NW of the volcano.] Sources: Coordinadora Nacional para la Reducción de Desastres (CONRED), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)

Chikurachki | 23 April-29 April 2003 | Continuing ActivityCite this Report
Chikurachki Paramushir Island (Russia)	Chikurachki, a volcano located on Paramushir Island in the North Kuriles, began erupting on 18 April 2003. A KVERT update for 25 April stated that the eruption continued and satellite data confirmed that ash plumes had moved SE and occasionally E during 22-25 April. The plumes attained lengths over 100 km. On 22 April observers at Vasiliev Cape on Paramushir Island saw a white gas-steam plume rise 500 m above the volcano's crater. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Fuego | 23 April-29 April 2003 | Continuing ActivityCite this Report
Fuego South-Central Guatemala	The Washington VAAC reported that on 28 April Fuego produced intermittent ash eruptions. One cloud was observed at ~ 7 km a.s.l., traveling SW at 19-29 km per hour. Although remote sensing was complicated by poor visibility due to high cirrus clouds and smoke from fires, some eruptive puffs remained recognizable when they blew over the coast. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)
Guagua Pichincha | 23 April-29 April 2003 | Continuing ActivityCite this Report
Guagua Pichincha Ecuador	During the week Guagua Pichincha continued to display seismic unrest, typically with several earthquakes per day but including 16 long-period earthquakes on 26 April. During 23, 24, 26, and 27 April observers on the mountain typically smelled sulfur, but qualitative assessments of fumarolic output varied. In conditions of poor visibility, observers sometimes heard the sound of gases escaping in the crater. In overview, the volcano's activity has not entirely tapered off. Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
Karymsky | 23 April-29 April 2003 | Continuing ActivityCite this Report
Karymsky Eastern Kamchatka (Russia)	KVERT reported that Karymsky's seismicity was above background during the week ending 25 April, an interval when instruments registered ~40-100 volcanic earthquakes per day. The character of the seismicity suggested ash-and-gas explosions up to 1,000 m above the volcano's crater. According to Russian satellite data, ash deposits were detected ~35 km away in various directions from the volcano; these were noted the previous week, on 19-22 April, but not previously reported here. According to other observers on 21 April, an ash-and-gas plume rose 1,500 m above the volcano's crater. The level of concern color code stood at Yellow. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Kilauea | 23 April-29 April 2003 | Continuing ActivityCite this Report
Kilauea Hawaiian Islands (USA)	For the week ending 29 April eruptive activity continued unabated from the Pu`u `O`o vent of Kilauea. The flows on Pulama pali were frequently visible at night as streams of incandescence from the top of the pali down to the coastal flats. Late in the previous week and early in this week, the east arm of the Mother's Day flow split in two with the western segment being more active. A new ocean entry near Lae`apuki only lasted a day before the flow stagnated. Scattered surface breakouts were seen throughout the inflating Kohola flow, especially on its W side. The National Park Service has marked trails out to the closest activity. As of 24 April, lava entered the ocean at two point along the West Highcastle delta. Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Klyuchevskoy | 23 April-29 April 2003 | Continuing ActivityCite this Report
Klyuchevskoy Central Kamchatka (Russia)	A KVERT report on Kliuchevskoi issued on 25 April stated that above-background seismicity, including abundant tremor, prevailed during the week. This report also revealed that the ash explosions of 17-18 April had sent material 1-2 km above the crater. Modest thermal anomalies registered in satellite data for 18-19 April and plumes around that time extended E for 20-200 km. The respective ash-bearing plumes of 20 and 23 April traveled over 10 km NE and 20 km SW. As of 25 April the Concern Color Code remained at Yellow. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
Popocatepetl | 23 April-29 April 2003 | Continuing ActivityCite this Report
Popocatepetl Mexico	On 24 April at 2050 Popocatépetl issued a moderate explosion that threw incandescent fragments 1.5-2.0 km above the crater and generated an ash column that rose to ~2.5 km above the crater. The plume was initially carried E. This activity was related to the destruction of a small dome that formed in the past few days. After the explosion, activity dropped to its previous more tranquil levels. A small explosion occurred late on 26 April, followed by a clear increase in vigor on 28 April, including another moderate explosion at 0120 that day. Incandescent fragments landed on the E and NE flanks up to ~800 m from the crater. The outburst included a 40-second phase of greatest intensity. Ash falls were not reported. Hours later on 28 April instruments began to register harmonic tremor of moderate amplitude, signals that continued for 13 hours. During the next day the eruptive vigor dropped to modest levels (only four exhalations of low intensity occurred, a smaller number than typical, and chiefly containing steam and gas rather than ash). Scientists attributed the 28 April eruption and increased eruptive vigor to advanced rates of lava ascent and extrusion. They suggested that these may have been higher than seen either earlier this year or near the end of last year. The hazard status was raised one increment, to Yellow phase 3. In addition, the highway traversing the Cortés pass was closed to traffic for two days, 29-30 April. Source: Centro Nacional de Prevencion de Desastres (CENAPRED)
Sheveluch | 23 April-29 April 2003 | Continuing ActivityCite this Report
Sheveluch Central Kamchatka (Russia)	A 25 April report on Shiveluch from KVERT stated that, based on seismic data a hot pyroclastic avalanche possibly took place on 23 April. Also, a M 2.25 earthquake occurred this day. Intermittent spasmodic volcanic tremor registered all week. According to visual data from Klyuchi, an ash plume rose 1,500 m above the dome on 24 April; gas and steam plumes rose 50-500 m above the dome on 19-21 and 24 April and the plumes blew 10 km to the E and SE, respectively. Clouds typically obscured the volcano on the other days. Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Weekly Reports Archive

Since the Weekly Volcanic Activity Report began in November 2000, there have been 20,019 individual reports over 1,216 weeks (average of 16 per week) on 332 different volcanoes.

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

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 Criteria & Disclaimers

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.

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.

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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.

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 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)