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Posts Tagged ‘volcanism’

Eyjafjöll Eruption Update – April 3

Posted by feww on April 3, 2010

Serial No  1,532. If any posts are blocked in your country, please drop us a line.

Fimmvörduháls Eruption May be Intensifying – A Second Fissure Has Appeared

A new volcanic fissure has appeared near Eyjafjallajökull in southern Iceland to the northwest of the original fissure on March 31. It may be a sign that the eruption at Fimmvörduháls is intensifying.

A pilot on a sight-seeing flight observed the vent at about 7:00PM  on Wednesday (local time). He saw a sudden flash of light followed  by a new rift, which opened up immediately after, a report said.


The natural-color satellite image (ALI on NASA’s EO-1) above shows a new fissure at Fimmvörduháls near Eyjafjallajökull ejecting steam. The vent, which appeared on March 31, is located  northwest of the original vent. Source: NASA


Map of the Lava flow. Click image to enlarge.
Full map including flow data and legend available at Map of the lava flow from 21 - 31 March 2010 (by Eyjólfur Magnússon, pdf file)

Latest and the most spectacular video of the eruption:

Earlier Videos

Technical information:

Webcams – Volcanoes in Iceland

Latest Images (RUV): http://www.ruv.is/flokkar/hamfarir

Related Headline News

Related Sites in Iceland (English)

Fire-Earth Links:

Posted in Eyjafjallajökull, Eyjafjöll, Fimmvörduháls, Hrunagil canyon, Hvannárgil | Tagged: , , , , , , | 5 Comments »

2010 Year of Super Volcanoes?

Posted by feww on January 30, 2010

Global Volcanism is on the rise!

2010 May Prove to Be Year One of Super Volcanic Activities

Fire-Earth Moderators believe the increase in global volcanism could  include renewed activities at some of the planet’s super volcanoes.

VolcanoWatch Weekly [28 January 2010]

VoW: Volcano Ash Threatens Ecuador’s Ambato City

19 – 26 January 2010 – SI /USGS Weekly Volcanic Activity Report

New activity/Unrest

Volcano News (Source: GVP)

MVO reported that during 15-22 January activity from Soufrière Hills consisted of cycles of vigorous ash venting, rockfalls, and pyroclastic flows. On 18 January, a small lava-dome collapse from the W side of the volcano generated a large pyroclastic flow that traveled 4 km and reached the sea.

IG reported that during 20-26 January explosions from Tungurahua were detected by the seismic network. Ashfall was noted almost daily in areas to the SW and sometimes to the W and NW. During 20-23 January lava fountains and explosions ejected incandescent blocks that fell onto and rolled down the flanks.

Ongoing Activity

Barren Island, Andaman Is;  Batu Tara, Komba Island (Indonesia); Chaitén, Southern Chile; Fuego, Guatemala; Gaua, Banks Islands (SW Pacific);  Karymsky, Eastern Kamchatka;  Kilauea, Hawaii (USA);  Kliuchevskoi, Central Kamchatka (Russia);  Llaima, Central Chile;  Sakura-jima, Kyushu;  Santa María, Guatemala;  Shiveluch, Central Kamchatka (Russia);  Suwanose-jima, Ryukyu Islands (Japan).

Related Links:

More Links:

FEWW Volcanic Activity Forecast

VolcanoWatch Weekly [ previous 4 entries ]

Posted in Chaiten, Global Volcanism, Soufrière Hills, Tungurahua, Volcano News | Tagged: , , , , , , , , , | 5 Comments »

Rhyolitic volcanoes pack a much bigger punch

Posted by feww on October 11, 2009

Quote of the Day:

“The largest eruptions on the planet have been rhyolitic …  you might have fewer of these volcanoes, but they pack a way bigger punch.”

—Jonathan Castro of the Institut des Sciences de la Terre in Orléans, France.


Flow banding in rhyolite lava from Mono-Inyo Craters volcanic chain, California (black bands composed of obsidian). Source: USDI

Large rhyolitic volcanoes include

  • Yellowstone, Wyoming (hotspot track near the Idaho-Oregon border)
  • Long Valley, California
  • Valles, New Mexico
  • Chaiténvolcano, Chile
  • Japanese Volcanoes
  • Taupo Volcanic Zone,  New Zealand
  • Ethiopian hotspot in northeastern Africa

Chaiten - UPI
After 9,000 years of slumber, Chile’s Chaiténvolcano erupted spewing lava and ejecting ash up to 20 km into into the atmosphere, with lightning added for extra dramatic effect. (Photograph by Carlos Gutierrez/UPI,  dated May 3, 2008) . Image may be subject to copyright.

Rhyolite often erupts explosively because its high silica content results in extremely high viscosity (resistance to flow), which hinders degassing. When bubbles form, they can cause the magma to explode, fragmenting the rock into pumice and tiny particles of volcanic ash.

Rhyolite:

Rhyolite which is erupted at temperatures of 700 to 850° C, is a light-colored rock consisting of

  • Silica (SiO 2 ) content greater than about 68 percent (by weight )
  • Sodium and potassium oxides up to  about 5 percent.
  • Common mineral types include biotite, feldspar and quartz (found in a glassy matrix)

Related Links:

FEWW Volcanic Activity Forecast

Recent Posts on Chaitén:

Posted in Chaiten, Long Valley, Taupo Volcanic Zone, Valles, Yellowstone | Tagged: , , , , | Leave a Comment »

Chaitén Still Awake!

Posted by feww on September 29, 2009

Chaitén: A New Phase of Activity?

On June 29, 2009, after a magnitude 5.3 quake struck off coast of Isen, Chile, at a depth of 10km, the Moderators forecast:

FEWW believes that the quake could be followed by more shocks, a number of which could be larger in magnitude, along the Chile Ridge, near the coast of Chile and about the subducting Nazca Plate. Additional seismic activity in the region could result in a new, more intense phase of activity in Chaitén, or prime other regional volcanoes for eruption.

Well, Chaitén is still awake, doing what volcanoes do best: Spewing ash, steam, sulfur…

Ash and Steam Plume from Chaitén

chaiten_ali_2009270
The Advanced Land Imager (ALI) aboard the NASA/USGS Earth Observing-1 (EO-1) satellite acquired this natural color image of Chaitén on September 27, 2009, at roughly 10:30 am local time.  According to a report, there was an ash plume extending 56 km (35 miles) northwest of the summit at the time the image was taken.
NASA image by Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption by Robert Simmon. [Edited by FEWW]

Related Links:

Posted in Chaiten, Chaiten volcano, Plate Tectonics, obduction, oceanic tectonic plate, orogeny. Tagged: block rotation | Tagged: , , , , , , | Leave a Comment »

VolcanoWatch Weekly [23 September 2009]

Posted by feww on September 24, 2009

Magnitude 6.4 EQ occurred off SW of Puerto Vallarta, Jalisco, Mexico, at a depth of 35 km, today.

FEWW Comments: The strong earthquake may have primed for eruption either one or both of two volcanoes Bárcena, which forms the island of San Benedicto, and Socorro, located on island of the same name, about 380 km to the west of the EQ location.

VOW1: Bárcena


Bárcena volcano forms the elongated island of San Benedicto, seen here from the SW in March 1955. The tuff cone with the circular summit crater at the center and the lava delta to the right were formed during an eruption in 1952-53, the only eruption known from this volcano in historical time. Pleistocene trachytic lava domes are located at the far NE tip of the island. Dark-colored lava domes from the 1952-53 eruption can be seen in the summit crater. Photo by Adrian Richards, 1955. Caption: GVP

VOW2: Socorro


Cerro Evermann, the high point of Socorro Island, rises above a Mexican Naval camp near the southern tip of the island. Socorro lies in the Revillagigedo Islands south of Baja California. Cerro Evermann is a large tephra cone and lava dome complex that forms the 1050-m-high summit of the volcano. Rhyolitic lava domes have been constructed along flank rifts, and silicic lava flows erupted from summit and flank vents have created an extremely irregular shoreline. Only minor explosive activity has occurred in historical time. Photo by Martha Marin, 1998 (Mexican Navy).
Caption: GVP

map_ of mexico_volcanoes
Bárcena  and Socorro are shown to the lower left of the map.

SI /USGS Weekly Volcanic Activity Report
(16 September – 22 September 2009)

New activity/Unrest:

News From GVP:

  • KVERT reported that although seismic activity from Kliuchevskoi did not exceed background levels during 11-18 September, weak tremor was detected. Strombolian activity that ejected tephra 70 m above the crater was seen at night on 16 and 17 September.
  • KVERT reported that during 11-18 September seismic activity from Shiveluch was above background levels. On 13 September, pyroclastic flow deposits 5 km long were seen on the S part of the lava dome.  —GVP

Ongoing Activity:

Related Links:

FEWW Volcanic Activity Forecast

Other Related Links:

Posted in Supervolcanoes, Volcanic Activity Report, VolcanoWatch, VolcanoWatch Weekly | Tagged: , , , , , , , , , , , , , | Leave a Comment »

VolcanoWatch Weekly [9 September 2009]

Posted by feww on September 11, 2009

VOW: Toba the Sleeping Colossus

Toba
Lake Toba, Sumatra, Indonesia – Landsat photo – Source: NASA

Lake Toba is a supervolcano, 100 kilometres long and 30 kilometres wide, and 505 metres (1,666 ft) at its deepest point. Located in the middle of the northern part of the Indonesian island of Sumatra with a surface elevation of about 900 metres (2,953 ft), the lake stretches from 2.88°N 98.52°E  to 2.35°N 99.1°E.  It is the largest volcanic lake in the world. It’s also the site of a supervolcanic eruption that occurred about 74,000 years ago, a massive climate-changing event. The eruption is believed to have had a VEI intensity of 8. This eruption, believed to have been the largest anywhere on Earth in the last 25 million years, may have had catastrophic consequences globally; some anthropologists and archeologists believe that it killed most humans then alive, creating a population bottleneck in Central Eastern Africa and India that affected the genetic inheritance of all humans today. (Source: Wikipedia).

Toba Large
Lake Toba Topography.
Source: Andaman Org.

Toba catastrophe theory

The Toba catastrophe theory holds that 70,000 to 75,000 years ago, a supervolcanic event at Lake Toba, on Sumatra, plunged the Earth into a mini-ice-age lasting several thousand years, reducing the world’s human population to 10,000 or even a mere 1,000 breeding pairs, creating a bottleneck in human evolution. The theory was proposed in 1998 by Stanley H. Ambrose of the University of Illinois at Urbana-Champaign.

The Toba eruption (the Toba event) occurred at what is now Lake Toba about 67,500 to 75,500 years ago. It had an estimated Volcanic Explosivity Index of 8 (described as “mega-colossal”), making it possibly the largest explosive volcanic eruption within the last twenty-five million years. It had a volume 300 cubic km greater than the Island Park Caldera supereruption (2500 cubic km) of 2.1 million years BP.

The total amount of erupted material was estimated at about 2,800 km³ — about 2,000 km³ of ignimbrite that flowed over the ground, and some 800 km³ that fell as ash, with the wind blowing most of it to the west. The pyroclastic flows of the eruption destroyed an area of 20,000 square kilometers, with ash deposits as thick as 600 metres near the main vent [ cf, 1980 eruption of Mount St. Helens ejected about 1.2 km³;  of material, whilst the largest volcanic eruption in historic times, at Mount Tambora in 1815, emitted the equivalent of 100 km3 of dense rock.] The eruption was also about three times the size of the latest Yellowstone eruption of Lava Creek 630,000 years ago. (Source: Wikipedia).

volcanic features of toba
The eruption of 73,000 years ago left the Sibandung caldera.  Lake Toba is surrounded by two small, active volcanos as well as several updomed areas and hot springs. These features indicate that there is activity below the surface today and that pressure is rising. Samosir island, too, is evidence for upthrust from below. From the record it seems that Toba produces major eruptions every 300-400,000 years. Source: Andaman Org.

Volcanic features in and around Lake Toba:

Grey area: Present-day topographic depression
green area: Updomed areas

Area # 1.  Sibandung caldera: made 73,000 years ago by the Toba YTT event (Young Toba Ash)
Area # 2. Haranggaol caldera: made 500,000 years ago by the Toba MTT event (Middle Toba Ash)
Area # 3.  Sibandung caldera: made 800,000 years ago by the Toba OTT event (Old Toba Ash)

The MTT and OTT events were not as large as the YTT event of 73,000 years ago
but were still major eruptions of at least VEI 7.

V1 Tandukbenua (Sipisopiso) – young dacit-andesite volcano
V2 Pusubukit volcano – young dacit-andesite volcano
D1 Pardepur dacite domes
D2 Tuk-tuk rhyolite dome
HS Hot springs
Source: Andaman Org.

Recent Activity

Large earthquakes have occurred in the vicinity of the volcano more recently, notably in 1987.  Other earthquakes have occurred in the area in 1892, 1916, and 1920-1922.

Lake Toba lies near the Great Sumatran fault which runs along the centre of Sumatra called the Sumatra Fracture Zone. The volcanoes of Sumatra and Java are part of the Sunda Arc, a result of the northeasterly movement of the Indo-Australian Plate which is sliding under the eastward-moving Eurasian Plate. The subduction zone in this area is very active: the seabed near the west coast of Sumatra has had several major earthquakes since 1995, including the 9.3 2004 Indian Ocean Earthquake [followed by the deadly tsunami] and the 8.7 2005 Sumatra earthquake, the epicenters of which were around 300 km from Toba Lake. (Source: Wikipedia).

SI /USGS Weekly Volcanic Activity Report
(26 August-1 September 2009)

New activity/unrest:

Notes [Source: GVP]

RVO reported that during 28 August-3 September white and gray ash plumes from Rabaul caldera’s Tavurvur cone rose 1.5 km above the crater and produced ashfall in Rabaul town (3-5 km NW) and surrounding areas.

The Washington VAAC reported that on 6 September an explosion from San Cristóbal produced an ash plume that rose to an altitude no higher than 8.5 km (28,000 ft) a.s.l. The plume drifted 75 km W.

Ongoing Activity:

Related Links:

FEWW Links:

FEWW Volcanic Activity Forecast

Posted in Sumbawa Island, Supervolcanoes, Toba catastrophe theory, Volcanic Activity Report, VolcanoWatch, VolcanoWatch Weekly, toba, toba lake, toba volcano | Tagged: , , , , , , , , , , | Comments Off

Shiveluch Release Plumes of Ash

Posted by feww on August 4, 2009

More Activity at Shiveluch Volcano

shiv_amo_2009215
A  true-color image of Shiveluch captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on August 3, 2009. The volcanic plume blows away from the summit, crossing the coastline and fanning out over the Bering Sea. The plume’s relatively dark color compared to nearby clouds suggests the presence of volcanic ash.  One of Kamchatka’s largest volcanoes, with a 3,283 meters high summit,  Shiveluch has undergone about 60 significant eruptions in the past 10,000 years.
NASA image courtesy MODIS Rapid Response Team, Goddard Space Flight Center. The Rapid Response Team provides daily images of this region. Caption by Michon Scott. [Edited by FEWW.]

Young Shiveluch: 56°38′ N, 161°19′ E, elevation: active dome about 2,800 m, summit of Old Shiveluch 3,283 m


Shiveluch volcano seen from the southeast: Young Shiveluch with its active dome is to the left, and Late Pleistocene Old Shiveluch is to the right of the photo. Source: Institute of Volcanology and Seismology, Kamchatka, Image may be subject to copyright.

FEWW Links:


Posted in Bering Sea, Kamchatka volcanoes, volcanic plume, volcano images, volcanoes | Tagged: , , , , | 2 Comments »

Nyiragongo Unrest

Posted by feww on July 25, 2009

Plume from Nyiragongo

nyiragongo_ali_2009178
Nyiragongo Volcano in the Democratic Republic of the Congo released a small plume on June 27, 2009, as the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite passed overhead.

NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) sensors detected hotspots on six different occasions between April 10 and May 4, 2009.  The plume observed by ALI in late June may be a continuation of the low-level activity.

Nyiragongo is a stratovolcano—a steep-sloped structure made of alternating layers of solidified ash, hardened lava, and rocks released by previous eruptions. In contrast to the low profile of neighboring Nyamuragira, Nyiragongo rises to a height of 3,470 meters (11,384 feet) above sea level. Lava flows from Nyiragongo caused substantial casualties in 1977 and 2002.  NASA image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 Team. Caption by Michon Scott. [Edited by FEWW.]

Related Links:

Posted in Nyamuragira, active volcanoes, lava flow, volcanic unrest, volcanoes | Tagged: , , , , | Leave a Comment »

VolcanoWatch Weekly [23 July 2009]

Posted by feww on July 23, 2009

Volcanic Activity Report: 15 July – 21 July 2009

Source: Global Volcanism Program (GVP) – SI/USGS Weekly Volcanic Activity Report

VOW: Revisiting Mount Tambora Volcano, Sumbawa Island, Indonesia

Tambora
On April 10, 1815, the Tambora Volcano produced the largest eruption in recorded history. An estimated 150 cubic kilometers (36 cubic miles) of tephra—exploded rock and ash—resulted, with ash from the eruption recognized at least 1,300 kilometers (808 miles) away to the northwest. While the April 10 eruption was catastrophic, historical records and geological analysis of eruption deposits indicate that the volcano had been active between 1812 and 1815. Enough ash was put into the atmosphere from the April 10 eruption to reduce incident sunlight on the Earth’s surface, causing global cooling, which resulted in the 1816 “year without a summer.”

This detailed astronaut photograph depicts the summit caldera of the volcano. The huge caldera—6 kilometers (3.7 miles) in diameter and 1,100 meters (3,609 feet) deep—formed when Tambora’s estimated 4,000-meter- (13,123-foot) high peak was removed, and the magma chamber below emptied during the April 10 eruption. Today the crater floor is occupied by an ephemeral freshwater lake, recent sedimentary deposits, and minor lava flows and domes from the nineteenth and twentieth centuries. Layered tephra deposits are visible along the northwestern crater rim. Active fumaroles, or steam vents, still exist in the caldera.

In 2004, scientists discovered the remains of a village, and two adults buried under approximately 3 meters (nearly 10 feet) of ash in a gully on Tambora’s flank—remnants of the former Kingdom of Tambora preserved by the 1815 eruption that destroyed it. The similarity of the Tambora remains to those associated with the AD 79 eruption of Mount Vesuvius has led to the Tambora site’s description as “the Pompeii of the East.”

Astronaut photograph ISS020-E-6563 was acquired on June 3, 2009  [photo caption said acquired March 6, 2009] , with a Nikon D3 digital camera fitted with an 800 mm lens, and is provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center. The image was taken by the Expedition 20 crew. The image in this article has been cropped and enhanced to improve contrast. Lens artifacts have been removed. The International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by William L. Stefanov, NASA-JSC.

New activity/unrest:

Ongoing Activity:

  • Bagana, Bougainville
  • Barren Island, Andaman Is
  • Batu Tara, Komba Island (Indonesia)
  • Chaitén, Southern Chile
  • Egon, Flores Island (Indonesia)
  • Ibu, Halmahera
  • Kilauea, Hawaii
  • Makian, Halmahera
  • Rabaul, New Britain
  • Sarychev Peak, Matua Island
  • Semeru, Eastern Java (Indonesia)
  • Shiveluch, Central Kamchatka (Russia)
  • Suwanose-jima, Ryukyu Islands (Japan)

Related Links:

FEWW Links:

Posted in Batu Tara, Chaiten, Komba Island, Sakura-jima, Sarychev Peak | Tagged: , , , , , | 2 Comments »

VolcanoWatch Weekly [16 July 2009]

Posted by feww on July 16, 2009

Volcanic Activity Report: 8 July – 14 July 2009

Source: Global Volcanism Program (GVP) – SI/USGS Weekly Volcanic Activity Report

New activity/unrest:

NOTES: A large sulfur dioxide plume and several thermal anomalies from Manda Hararo that were detected in satellite imagery during 28-30 June prompted a science team to visit the area on 4 July. They saw new predominantly ‘a’a lava flows that were 2-3 m thick. The fissure was lined with scoria ramparts 30-50 m high.

On 10 July, AVO reported that a distinct thermal anomaly in Shishaldin’s summit crater observed intermittently since January 2009 became more intense during the previous month. AVO raised the Aviation Color Code and the Volcano Alert Level. (Source: GVP)

VOW: More Volcanoes to watch for 2009-10

  • Buvet
  • Colima
  • Rabul  [Explosive eruption more powerful than 1994 may occur]

Ongoing Activity:

  • Batu Tara, Komba Island (Indonesia)
  • Chaitén, Southern Chile
  • Dukono, Halmahera
  • Fuego, Guatemala
  • Kilauea, Hawaii (USA)
  • Pacaya, Guatemala
  • Rabaul, New Britain
  • Sakura-jima, Kyushu
  • Shiveluch, Central Kamchatka (Russia)

Latest U.S. Volcano Alerts and Updates

Alaska Volcano Observatory Update: July 16, 2009 0300 UTC

  • Redoubt Activity – Color Code YELLOW : Alert Level ADVISORY

  • Cleveland Activity – Color Code – UNASSIGNED: Alert Level UNASSIGNED

HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE: Wednesday, July 15, 2009 18:05 UTC

  • Kilauea Activity  -  Color Code ORANGE : Alert Level WATCH

  • Mauna Loa Activity – Color Code YELLOW : Alert Level ADVISORY

Related Links:

FEWW Links:

Posted in Buvet, Rabul, San Miguel, Sarychev Peak, Shishaldin | Tagged: , , , , | Leave a Comment »

Manam Volcano Coughs, Again!

Posted by feww on July 11, 2009

manam_ali_2009179
Manam Volcano, just off the coast of mainland Papua New Guinea, released a faint plume on June 28, 2009. The Advanced Land Imager (ALI) onboard NASA’s Earth Observing-1 (EO-1) satellite captured this photo-like image of the volcano the same day. Bright white clouds hover over the volcano’s summit. Clouds often collect over peaks, but these clouds could result from water vapor released by the volcano. Slightly darker in color, a pale blue-gray plume blows west-northwest from the summit and over the Bismarck Sea. NASA image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 Team. Caption by Michon Scott.

Manam Volcano

Country:  Papua New Guinea (PNG)
Region : Northeast of New Guinea
Volcano Type: Stratovolcano
Last Known Eruption: 2009 (continuing)
Summit Elevation: 1,807 m
Latitude: 4.080°S
Longitude: 145.037°E
Source: Global Volcanism Program (GVP)

Manam GVP
The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country’s most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical 1807-m-high basaltic-andesitic stratovolcano to its lower flanks. These “avalanche valleys,” regularly spaced 90 degrees apart, channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Five small satellitic centers are located near the island’s shoreline on the northern, southern and western sides. Two summit craters are present; both are active, although most historical eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE avalanche valley. Frequent historical eruptions, typically of mild-to-moderate scale, have been recorded at Manam since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas. Photo by Wally Johnson (Australia Bureau of Mineral Resources). Caption: GVP.

Major Volcanoes of Papua New Guinea


Manam, Papau New Guinea – May 9, 2006


An unusually clear day in Papua New Guinea provided the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite with this view of the Manam Volcano on May 9, 2006. The volcano is one of the country’s most active volcanoes, and it has erupted frequently since 1616. Its current eruption began on October 24, 2004, when the volcano erupted explosively. Though MODIS has detected many ash plumes from the volcano since that time, none have been so large. Evidence that the volcano was still rumbling on May 9 comes from the tan plume of ash that streams southeast from the mountain summit.  NASA image created by Jesse Allen, Earth Observatory, using data obtained courtesy of MODIS Rapid Response team.

More of the images acquired in 2006 are posted at: http://earthobservatory.nasa.gov/NaturalHazards/event.php?id=16618

manam_omi_2005028
When the Manam volcano erupted explosively in the middle of the night on January 27, 2005, it sent a cloud of ash and sulfur dioxide over New Guinea. The large eruption killed at least one person, injured several others, and destroyed the volcano monitoring station on the small volcanic island. About 12 hours after the eruption (January 28), the Ozone Monitoring Instrument (OMI) flew over on NASA’s new Aura satellite. This image was produced from preliminary, uncalibrated data provided by OMI.

OMI saw a large cloud of sulfur dioxide drifting west over the island of New Guinea. The gas is measured in Dobson Units (DU), the number of molecules in a square centimeter of the atmosphere. Red pixels cover the areas of highest concentration, while the lowest concentrations are represented by pink pixels. If you were to compress all of the sulfur dioxide a column of the atmosphere into a flat layer at standard temperature and pressure, one Dobson Unit would be 0.01 millimeters thick and would contain 0.0285 grams of SO2 per square meter. On January 28, the atmosphere over New Guinea contained up to 50 Dobson Units (red regions), or 1.425 grams of SO2 per square meter.

Once in the atmosphere, sulfur dioxide combines with water to create a highly reflective haze of sulfuric acid. The haze reflects sunlight away from the Earth, so if the eruption is big enough, it can lead to cooler temperatures for several years before the sulfuric acid falls out of the atmosphere as rain. In 1991, Mount Pinatubo sent millions of tons of SO2 into the atmosphere, and global temperatures, which had been expected to rise because of the greenhouse effect, leveled out. While large, Manam’s eruption does not compare to Mount Pinatubo in magnitude, and it is not clear if or how the eruption will impact regional climate.

For more information about Manam’s eruption, please visit the Darwin Volcanic Ash Advisory Center.

OMI was added to the Aura satellite as part of a collaboration between the Netherlands’ Agency for Aerospace Programs and the Finnish Meteorological Institute. The sensor tracks global ozone change and monitors aerosols in the atmosphere.

NASA image courtesy Simon Carn, Joint Center for Earth Systems Technology (JCET), University of Maryland Baltimore County (UMBC). Caption: Earth Observatory.

Continued Eruption of Manam Volcano – October 24, 2004

manam 2004 EO
Collection: NASA Earth Observatory Collection – Title: Continued Eruption of Manam Volcano
Description: The island of Manam sits in the Bismarck Sea across the Stephan Strait from the east coast of mainland Papua New Guinea. Only 10 kilometers wide, the island results from the activity of the Manam Volcano, one of the country?s most active. In this image from the Moderate Resolution Imaging Spectroradiometer (MO DIS) on NASA’s Aqua satellite on  , a large ash plume has spread northwestward from an eruption of Manam, located at bottom right. The thermally active areas on the volcano have been detected by MODIS and are outlined in red. Interestingly, the winds higher up in the atmosphere appear to have been blowing in the opposite direction at the time this image was captured. Streamers of clouds stretch from the coast northeastward over the ash plume and farther out to sea. In the afternoon sunlight, the thicker clouds cast shadows down onto the ash plume. North of the cloud streamers, the tail of the ash plume is being rippled by the wind into rows of evenly spaced, nearly parallel waves. The Manam Volcano has an interesting structure. Its 1,870-meter summit is bare and carved by four large avalanche valleys that radiate from the summit down the flanks. These valleys are spaced roughly 90 degrees apart around the cone-shaped mountain, and lava and pyroclastic debris flows have funneled through these valleys and reached the coast in past eruptions. The volcano has two summit craters, and both are active. The island is inhabited, and emergency agencies urged residents to move to safer parts of the island; however, according to news reports on October 27, no casualties had yet been reported. NASA image courtesy Jeff Schmaltz, MOD IS Rapid Response Team, NASA-GSFC  —  UID: SPD-ETOBS-12556 –  Image ID: 173708  — Original caption.

Related Links:

Posted in Climate Change, aerosols, sulfur dioxide, volcanic activity, volcanic eruption | Tagged: , , , , | Leave a Comment »

Shiveluch spewes large plumes of ash

Posted by feww on June 30, 2009

Shiveluch volcano on the Kamchatka Peninsula ejects ash to a height of 7km

Shiveluch volcano on the Kamchatka Peninsula, Russia’s northernmost active volcano,  spewed out ash to a height of some 7,000 meters (23,000 feet), the local geophysics service reported on Monday.

The service had registered about 60 tremors within the area in the previous 24 hours.

“Some of them were followed by powerful ash bursts and avalanches,” a spokesman for the service said.

Shiveluch volcano erupted in December 2006. Local scientists expect the volcano to erupt explosively soon.

“Volcanic activity over the past two-three years has significantly altered the contour of the volcano, with the crater increasing in size by 50% and the slopes becoming far steeper.” RiaNovosti reported.

Related Links:

Previous Comments by FEWW

FEWW Volcanic Activity Forecast

Posted in Explosive Eruption, Kamchatka peninsula, Kamchatka volcanoes, Koryakski volcano, Russian volcano | Tagged: , , , , | Leave a Comment »