Volcano Watch: Global Edition

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Volcano Watch articles generally focus on Hawaiian volcanism, because they are written by USGS Hawaiian Volcano Observatory (HVO) staff. But there are many other volcanoes on the rest of the planet to watch—590 are known to have been active since A.D.1500.

The "Smithsonian/USGS Weekly Volcanic Activity Report (WVAR)," which is essentially a Volcano Watch for Earth, offers a global perspective. As its ungainly label suggests, the report is a collaborative effort of the Smithsonian Institute's Global Volcanism Program and the U.S. Geological Survey's Volcano Hazard Program. The latter is HVO's parent organization.

The WVAR divides volcanic activity that occurred during the previous week into two categories: (1) New Activity/Unrest, and (2) Ongoing Activity. Each report includes the volcano's name, its coordinates and elevation, a brief description of the activity, a summary of the volcano's history, and the source of the information. WVARs are updated every Wednesday by 11:00 p.m., GMT (Greenwich Mean Time).

To be included in a WVAR, volcanic activity must meet one of the following criteria:
• A volcano observatory raises or lowers the alert level at the volcano.
• An advisory is released by a Volcanic Ash Advisory Center, 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 is issued.
• Observers report a significant change in volcanic activity, including—but not restricted to—pyroclastic flows, lahars, lava flows, lava dome collapse, or increased unrest.

If volcanic activity is not reported, it's not included in the report. Therefore, WVARs do not necessarily list every volcanic event on Earth. For instance, some volcanic activity occurs in areas that are too remote to be directly observed or readily reported.

Most WVARs are submitted by volcano observatories. HVO is one of 76 observatories that are members of the World Organization of Volcano Observatories (WOVO), which is a commission of IAVCEI (International Association of Volcanology and Chemistry of the Earth's Interior).

Some of the contributing observatories are Volcanic Ash Advisory Centers (VAACs), which are responsible for advising international aviation of the location and movement of volcanic ash clouds. Nine VAACs are located around the world, and they are in Anchorage, Alaska; Buenos Aires, Argentina; Darwin, Australia; London, United Kingdom; Montreal, Canada; Tokyo, Japan; Toulouse, France; Washington, DC; and Wellington, New Zealand. Collectively, they monitor nearly all of Earth's airspace, relying heavily on satellite imagery. The primary reason that VAACs exist is to keep aircraft from flying into volcanic ash plumes as they did in April 2010, when the eruption of an Icelandic volcano spread ash over Europe.

In its listing of New Activity/Unrest, the August 10-16, 2011, WVAR included a largely unknown volcano—Dukono in Halmahera, the largest island in the Maluku Islands, which is part of the North Maluku province of Indonesia. The report was as follows:

"DUKONO Halmahera 1.68°N, 127.88°E; summit elev[ation] 1335 m. According to a news article, activity at Dukono has continued to increase. On 11 August ash explosions were audible within a radius of about 7 km from the base of the volcano. Ash was ejected as high as 1 km above the crater, producing plumes that drifted E and S, and also approached Tobelo City (14 km ENE). Seismographs at the Dukono observation post recorded more than 100 eruption earthquakes. Based on analyses of satellite imagery, the Darwin VAAC reported that on 11 and 14 August ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. [above sea level] and drifted 93 km NW."

The report also included links to a geologic summary of the volcano's behavior and a list of information sources.

While the HVO Web site provides daily and monthly updates on volcanoes close to home (Hawai‘i Island), the Smithsonian/USGS Weekly Volcano Activity Reports make it easy to stay informed about volcanic events anywhere on Earth. To track global volcanism, please visit http://www.volcano.si.edu/reports/usgs/.

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Volcano Activity Update

A lava lake has been present within the Halema‘uma‘u Overlook vent over the past week, resulting in night-time glow visible from Jaggar Museum. Since reappearing several days ago, the lava lake has hosted repeated fluctuations in height. Such cycles of rise and fall have been a common occurrence during Kīlauea's ongoing summit eruption.

After several days of quiet, lava reappeared in Pu‘u ‘Ō‘ō last Sunday (August 21) and began to refill the crater. As of Thursday, August 25, lava had reached to within about 30 m (98 ft) of the east rim of Pu‘u ‘Ō‘ō, but still has a long way to go before getting back to its level prior to the August 3 flank breakout and crater collapse.

No earthquakes beneath Hawai‘i Island were reported felt this past week.