Activity for the week of 16 July-22 July 2003
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, notices of volcanic activity posted on these pages are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports on various volcanoes are published monthly in the Bulletin of the Global Volcanism Network.
New Activity / Unrest
| Sulawesi (Indonesia)
| 1.112°N, 124.737°E
| Elevation 1785 m
High levels of volcanic and seismic activity occurred at Soputan during mid-July. On 17 July at 1900 the Alert Level was raised to 2 (on a scale of 1-4) after incandescence was seen at the lava dome for about a day. Around 1150 the amplitude of volcanic tremor increased and at 1900 an increased level of incandescence was seen. On 18 July at 0630 incandescent lava avalanches suddenly occurred that were not proceeded by explosions or loud sounds. The avalanches were accompanied by a pyroclastic surge towards the WNW and an ash cloud that rose ~2 km above the summit. The cloud drifted N, depositing ash around the area of Tombasian, Tareran, Tompaso, Kawangkoan, Sonder, Tomohon, and Manado. The same day the Alert Level was raised to 3. On 19 July there were pyroclastic flows, ash explosions, Strombolian activity, and lava emission at the lava dome. Ash explosions continued through at least 21 July. According to news reports, some residents in villages near the volcano fled, including those in the villages of Kota Menara, Amurang, and Maliku around 10 km S of the volcano.
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Darwin Volcanic Ash Advisory Centre (VAAC), Terra Daily News, The Jakarta Post
| 16.72°N, 62.18°W
| Elevation 915 m
After a lava-dome collapse at Soufrière Hills on 12 July volcanic activity was at relatively high levels until 13 July when it slowly subsided. On the 13th activity had declined to very low levels, then the following morning a sudden vulcanian explosion occurred at the lava dome. Two more explosions occurred during the next 2 days. Pumice from these explosions reached 15 cm in size at Richmond Hill, declining to 4 cm in Olveston. Heavy ashfall from the collapse occurred over all the inhabited parts of Montserrat. The greatest ash thickness was recorded at the Vue Pointe Hotel, where it exceeded 15 cm in depth. After an explosion on 15 July, volcanic and seismic activity were relatively low, with only a few hybrid earthquakes and rockfalls each day. Scientists saw an open explosion crater in the collapse scar, with no new lava extruded. The bulk of the lava-dome structure was removed during the collapse. Pyroclastic flows impacted the area between Tar River Valley and Spanish Point.
Sources: Montserrat Volcano Observatory (MVO), Washington Volcanic Ash Advisory Center (VAAC)
| 19.514°N, 103.62°W
| Elevation 3850 m
On 17 July an explosion at Colima sent incandescent volcanic material to ~500 m above the volcano and produced a SW-drifting ash cloud to a height of ~ 3 km above the volcano. At least five pyroclastic flows traveled down the volcano's flanks to a maximum distance of ~2 km.
Source: Centro Universitario de Estudios e Investigaciones de Vulcanologia - Universidad de Colima
| Halmahera (Indonesia)
| 1.693°N, 127.894°E
| Elevation 1229 m
Satellite imagery on 21 July at 0724 showed an ash plume from Dukono that rose to a height of ~3 km a.s.l. and extended ~45 km NNE of the summit.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
| Siau Island (Indonesia)
| 2.781°N, 125.407°E
| Elevation 1797 m
Based on an aircraft report, the Darwin VAAC stated that a thick ash plume was visible above Karangetang at a height of ~7.5 km a.s.l. Ash was not visible on satellite imagery.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
| Hawaiian Islands (USA)
| 19.421°N, 155.287°W
| Elevation 1222 m
During 16-22 July at Kilauea, surface lava flows were visible on the coastal flat and upslope on the Pulama pali and Paliuli. No lava flowed into the sea. Generally, seismicity at Kilauea's summit continued at moderate levels, with 1-2 small low-frequency earthquakes per minute occurring at shallow depths beneath the summit caldera. There were some larger events at depths of a few kilometers. Small inflation and deflation occurred during the report week.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
| Central Kamchatka (Russia)
| 56.056°N, 160.642°E
| Elevation 4754 m
Seismicity was above background levels at Kliuchevskoi during 11-18 July. Several earthquakes occurred each day with magnitudes of 1.3-2.2 at depths around 30 km and at shallower levels. Explosions sent ash clouds to a height of ~1 km above the volcano and during 12-16 July ash clouds reached ~2 km above the volcano. Kliuchevskoi remained at Concern Color Code Orange.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| 19.023°N, 98.622°W
| Elevation 5393 m
During 16-22 July, moderate emissions of mainly gas and steam occurred at Popocatépetl. On 19 July at 0920 a moderate explosion produced an ash plume that rose ~3 km above the crater. After the event the volcano returned to its previous level of activity characterized by frequent and small steam-and-ash emissions. According to news reports, a small amount of ash fell in Mexico City. The international airport remained open, with minor disruptions to air traffic.
Sources: Centro Nacional de Prevencion de Desastres (CENAPRED), Washington Volcanic Ash Advisory Center (VAAC)
| 0.077°S, 77.656°W
| Elevation 3562 m
Rainfall at Reventador during 7-13 July remobilized ash on the volcano's flanks, causing lahars down Montana River. Travel on the Baeza highway was interrupted. Permanent tremor associated with degassing was recorded.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
| Eastern Java (Indonesia)
| 8.108°S, 112.922°E
| Elevation 3657 m
An ash cloud from Semeru was visible on satellite imagery on 21 July at 2316 extending ~75 km to the WSW.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
| 1.467°S, 78.442°W
| Elevation 5023 m
Seismic and volcanic activity were at relatively low levels at Tungurahua during 16-22 July, with emissions of steam and gas forming low-level plumes.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)
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
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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
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 monthly, and 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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