Volcanic ash was main danger from eruptions in 2005

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As we enter the New Year with the eruption of Kīlauea Volcano still going strong after 23 years, it is important to remember the world's other volcanoes that were active in 2005. They also required constant vigilance by scientists and others in nearby communities to understand their activity and keep people out of harms way.

Volcanic ash was main danger from eruptions in 2005...

View of eruption column rising from east crater at Anatahan. Column reached maximum height of about 2,500 m in less than 40 seconds.

(Public domain.)

A Weekly Volcanic Activity Report supported by the GVP and the U.S. Geological Survey is a good source of preliminary information. The weekly reports are archived according to date, volcano, and region.

A review of these preliminary reports shows that about 68 volcanoes generated some type of eruption in 2005. At least another 10 volcanoes showed signs of restless activity detected by scientists but did not erupt. The signs include an increased number of earthquakes or a change in the degassing, thermal activity, and deformation of a volcano.

Indonesia, which has most of the world's active volcanoes, topped the list, with 13 volcanoes erupting.

Seven volcanoes erupted in the U.S. and the Commonwealth of the Northern Mariana Islands (CNMI). Four showed signs of restless activity only.

Seven volcanoes also erupted in Papua New Guinea, including explosions from Mamam Volcano that displaced nearly 10,000 people from nearby villages, injured 14, and killed one.

The strongest and most persistent explosive activity occurred from two volcanoes in and surrounding the Pacific Ocean - Anatahan Volcano in the Commonwealth of the Northern Mariana Islands and Kliuchevskoi, Russia - and one in the Americas - Colima, Mexico. Anatahan, located 120 km (75 mi) north of Saipan, sent an ash column more than 10 km (35,000 ft) above sea level at least five times.

Kliuchevskoi's lava dome erupted many times, forming lava flows, hot-rock avalanches, and ash plumes that spread far downwind from the volcano, triggering many "red" alerts for jets flying between Asia and Europe and the U.S.

In late May, Colima Volcano generated the strongest eruption since it began erupting in 1999 and formed many pyroclastic flows and ash columns more than 7 km (23,000 ft) above sea level.

Galeras Volcano in Colombia, active since the mid-1990s, experienced increased earthquake activity and new eruptions. Concern for the safety of nearby communities led officials to order 9,000 people to evacuate in November (not all did).

Most of the active volcanoes in 2005 generated intermittent plumes of ash, gas, and steam a few hundred to a few thousand meters into the air. These ash plumes were variously associated with steam-driven explosions or accompanied the eruption of lava in the form of lava flows and fountains or short-lived explosive events.

Falling ash and volcanic gases adversely affected tens of thousands of people in Vanuatu, Indonesia, Chile, Papua New Guinea, Ecuador, the Commonwealth of Northern Mariana Islands, and the Comoros Islands in the Indian Ocean.

Langila Volcano in Papua New Guinea affected more than 10,000 people by erupting low ash plumes, resulting in increased cases of respiratory problems and eye irritation, damaged food gardens, and contaminated water.

The first historical eruption of Mount Dabbahu in Ethiopia spread ash over a localized area, which displaced an estimated 6,200 people for at least several days.

The beginning of 2006 is also a good time to remember our colleagues that gave their lives during their work to help people deal with natural hazards. In the Philippines, a helicopter crash took the lives of four Air Force crew members, four scientists from the Philippine Institute of Volcanology and Seismology, and its former director, Ray Punongbayan.

They were inspecting landslide-prone areas about 110 km (68 mi) from Mount Pinatubo volcano, looking for areas to resettle communities affected by typhoons in 2004.

To scientists and other volcano watchers across the globe tracking the world's ongoing eruptions and restless volcanoes and to communities living in the shadow of those volcanoes, the staff and associates of the Hawaiian Volcano Observatory wishes a safe and prosperous 2006.


Volcano Activity Update


During the past week, the number of earthquakes located beneath Kīlauea remains at levels typical of the current eruption. Inflation of the summit continues.

Eruptive activity at Pu`u `O`o also continues. On clear nights, glow is visible from several vents within the crater and on the southwest side of the cone. Lava is still flowing through the PKK lava tube from its source on the flank of Pu`u `O`o to the ocean, with a scattered surface flows breaking out of the tube. In the past week, flows were active intermittently about 1 kilometer (0.6 miles) downslope of Pu`u `O`o, on the steep slopes of Pulama pali, above the coastal plain, and just above the coastal plain at the 200-ft elevation. Surface flows on the pali are visible at night (weather permitting) from the end of Chain of Craters Road.

As of January 5, lava is entering the ocean at East Lae`apuki, in Hawai`i Volcanoes National Park. The active lava bench continues to regrow following the major collapse of November 28. Access to the ocean entry and the surrounding area remains closed, due to significant hazards. If you visit the eruption site, check with the rangers for current updates, and remember to carry lots of water when venturing out onto the flow field.

There were no earthquakes beneath Hawai`i Island reported felt within the past week.

Mauna Loa is not erupting. During the past week, the count of earthquakes located beneath the volcano remains at low levels. Inflation continues but at a slightly slower rate since early October 2005.