Activity for the week of 31 July-6 August 2002
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
| Papua New Guinea
| 5.519°S, 148.115°E
| Elevation 75 m
Qantas Airlines reported to the Darwin VAAC that an ash cloud to about ~3 km a.s.l. was observed on 2 August at 1450. Analysis of satellite data did not show ash.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
| New Britain (Papua New Guinea)
| 5.576°S, 150.516°E
| Elevation 724 m
Qantas Airlines reported that a rapidly increasing ash cloud was visible at 9.1 km a.s.l. on 3 August at 1440. The summit was obscured by clouds, so ash was not identifiable from satellite imagery. On 5 August at 0705 Air Niugini reported another ash cloud that was 18 km wide at 1.2 km a.s.l. extending 37 km NW. According to press reports, this plume was from an eruption that began on 5 August around 0530. By 0600, residents in Hoskins and Kimbe towns realized there had been an eruption when they saw thick clouds of ash drifting W across Kimbe Bay. Another eruption occurred about midday, raining ash on Hoskins. An estimated 10,000 to 15,000 people in villages at the foot of the volcano and surrounding areas could be affected by ashfall. Earthquakes were felt before the eruption.
Air Niugini reported that on 6 August at 0630 a 1.8- to 2.4-km-thick gray ash plume extended 148 km WNW at 7.6 km a.s.l. The Rabaul Volcano Observatory noted that at 0830 the ash column had reached 10 km above the volcano. A low-level ash plume identified on GMS visible satellite imagery at 0932 extended 111 km WNW with a width of 18 km. By 1132 the ash plume was 37 km wide based on visible satellite imagery. The Rabaul Volcano Observatory reported that eruptions were continuing on 6 August at 1800 with the ash plume moving NNW to N.
Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Papua New Guinea Post-Courier Online
| Sicily (Italy)
| 37.748°N, 14.999°E
| Elevation 3295 m
Activity continued at Etna during 31 July-6 August with brown ash explosions from Bocca Nuova crater. SO2 emissions were detected from Voragine crater on 4 August. Strong explosions originating in Northeast Crater were felt during the afternoon of 6 August. The area near Northeast Crater contained numerous bombs, some more than 70 cm in size weighing more than 30 kg.
Source: Etna Volcan Sicilien (Charles Rivière)
| Siau Island (Indonesia)
| 2.781°N, 125.407°E
| Elevation 1797 m
According to VSI, a small ash plume reached 400 m above the S part of the main crater of Karangetang this week. Crater II produced a small ash plume to 200 m. Seismicity decreased compared to the previous week. Karangetang remained at Alert Level 2 (on a scale of 1-4).
Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Darwin Volcanic Ash Advisory Centre (VAAC)
| Eastern Kamchatka (Russia)
| 54.049°N, 159.443°E
| Elevation 1513 m
During 27 July-2 August, seismicity remained above background levels at Karymsky. Local, shallow seismic events decreased from 250 to 150 events per day. The character of the seismicity indicated that weak ash-and-gas explosions and gas blow-outs possibly occurred. The duration and intensity of blow-outs increased. A 2-pixel-large thermal anomaly was visible on satellite imagery on 26 July. Karymsky remained at Concern Color Code Yellow ("volcano is restless").
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)
| Hawaiian Islands (USA)
| 19.421°N, 155.287°W
| Elevation 1222 m
By 6 August, only the the Wilipe`a entry was active at Kilauea, with five or six spigots sending lava off the leading edge of the bench into the water. The West Highcastle bench was steaming but had no lava. At the Highcastle kipuka, two actively advancing lobes of lava were found, one 160 m and the other 170 m from the western and eastern remnants, respectively, of the Chain of Craters Road, themselves only 40-60 m from water. Each lobe was moving very slowly.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
| Central Java (Indonesia)
| 7.54°S, 110.446°E
| Elevation 2910 m
During 29 July-4 August, incandescent lava avalanches traveled predominately down Merapi's SW flank into the upstream portions of the Sat, Lamat, Senowo, and Bebeng rivers. The avalanches reached a maximum run-out distance of ~2.6 km. A thin white plume rose ~400 m above the summit. Seismicity was dominated by signals from 237 lava avalanches. No pyroclastic flows were reported. Merapi remained at Alert Level 2 (on a scale of 1-4).
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
| DR Congo
| 1.408°S, 29.2°E
| Elevation 3058 m
Helicopter flights on 1 and 3 August revealed that the eruption that began on 25 July at Nyamuragira continued at a high rate. Two volcanic cones were visible growing on the eruptive fracture. The cones were built by the accumulation of spatter and ash from two very active 100- to 200-m-high lava fountains. Two large lava flows moved quickly and joined below the lowest cone to form a main flow. The main flow (estimated to be 15 km long) moved toward the NNE and changed direction after a few kilometers to move toward the NE. Many lateral overflows were visible on the E side of the main flow. The front of the main flow appeared to be very wide and lava covered a wide area, though it remained within the National Park boundaries. Permanent tremor was registered. The Alert Level remained at Yellow.
Source: UN Office for the Coordination of Humanitarian Affairs (OCHA)
| DR Congo
| 1.52°S, 29.25°E
| Elevation 3470 m
A helicopter flight over Nyiragongo on 1 August revealed a thick, dense plume rising from the crater at a high velocity. The inner crater was completely filled with dispersed gas, preventing visibility of any fresh lava that may be in the crater. No red glow has been seen during recent nights, but the permanent sustained tremor recorded on all stations confirmed that the volcano remained active with magma moving beneath it. Some individual shocks were recorded around the SW flank of Nyiragongo. The Alert Level remained at Yellow.
Source: UN Office for the Coordination of Humanitarian Affairs (OCHA)
| Eastern Java (Indonesia)
| 8.108°S, 112.922°E
| Elevation 3657 m
Activity at Semeru remained at a higher level than normal, but thick fog obscured the view. Seismicity increased compared to the previous week and was dominated by 744 explosion earthquakes. Semeru remained at Alert Level 2 (on a scale of 1-4).
Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)
| Central Kamchatka (Russia)
| 56.653°N, 161.36°E
| Elevation 3283 m
During 27 July-2 August, seismicity remained above background levels at Shiveluch and a lava dome grew in the active crater. Individual earthquakes of M 1.9-2.4, as well as a number of smaller earthquakes at depths of 0-6 km, were recorded. Other local seismic signals indicated that possible weak, ash-poor explosions rose to 1 km above the dome. Avalanches were also registered. Volcanic tremor increased in intensity on 29 July and remained high until 1 August. Tremor gradually decreased in amplitude during 1-2 August. Gas-and-steam emissions, some possibly including small amounts of fine ash, rose to ~1.5 km above the lava dome. On 30 July a short-lived explosion sent ash-and-gas plumes to ~3 km above the dome. Thermal anomalies of 1-4 pixels were visible on satellite images. On 28 July and 1 August, small steam-and-aerosol plumes were visible extending to the S and 35 km to the NW, respectively. KVERT decreased the Concern Color Code from Orange ("explosive eruption is possible within a few days and may occur with little or no warning") to Yellow ("volcano is restless").
Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
| 16.72°N, 62.18°W
| Elevation 915 m
Volcanic and seismic activity at Soufrière Hills during 26 July-2 August continued at an elevated level. The swarm of low-amplitude long-period earthquakes that began on 19 July continued, but decreased during the last 3 days of the report period. A flight on 1 August revealed that the new extrusion lobe on the N side of the summit had a broad whaleback form. Growth of the lobe was directed toward the N, giving rise to rockfalls and small pyroclastic flows in the upper parts of Tuitt's Ghaut and White's Ghaut. Torrential rainfall produced mudflows in the Belham Valley in the early hours of 28 August. SO2flux remained low.
Source: Montserrat Volcano Observatory (MVO)
| 1.467°S, 78.442°W
| Elevation 5023 m
Intermittent eruptive activity continued throughout the report period. Satellite observations were obscured the entire time, but visual reports by ground observers indicated frequent ash emissions. At least six pilot reports between 31 July and 6 August described ash plumes rising as high as 6 km a.s.l. and moving W or NW.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)
News Feeds and Google Placemarks
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. 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.
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.
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 page for that volcano and to the complete Weekly Report for that week.
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.
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RSS and CAP Feeds
An RSS (Really Simple Syndication) feed for the Weekly Volcanic Activity Report first made available on 5 March 2008 can be utilized with the aid of various free downloadable readers. The report content of the news 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. 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. On 12 March 2009, GeoRSS tags were added so that the latitude and longitude for each volcano could be included with the feed.
At the end of each individual report is a list of the sources used. We would like to emphasize that the World Organization of Volcano Observatories (WOVO) website (http://www.wovo.org/) lists the regional volcano observatories that have the most authoritative data for many of these events.
CAP (Common Alerting Protocol) feeds are XML files specifically formatted for disaster management.
Google Earth Placemarks
A Google Earth network link for the Weekly Volcanic Activity Report was first made available on 1 April 2009. This file 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 page for that volcano and to the complete Weekly Report for that week.