Sunday, February 27, 2011

Volcano Glossary Part 1

pyroclastic - refers to the fragmental materials formed by explosive processes of volcanoes.

aa - Lava of basaltic composition that has a very rough surface. (Contrast with pahoehoe lava)

ash - Fine granular pyroclastic material, with grains 0.04 inches or less in diameter. Hardened ash is called tuff.

basalt - Lava, usually black or very dark gray, that has 55 percent silica or less. Ocean floors of the world are covered by basalt lava flows.

base surge - A ring-shaped cloud of gas and suspended solid debris that moves (surges) radially outward from the base of a vertical explosion column at high velocity as a density flow.

blast surge - a blast or explosion directed outward from a volcano with great force.

block - a solid volcanic rock (pyroclast) ejected from a volcano and having a diameter greater than 2.6 inches.

bomb - a viscous particle (pyroclast) of a diameter greater than 2.6 inches ejected from a volcano before the particle is frozen solid. Shapes vary greatly - spindles, cow pies, ribbons, etc.

Bibliography
Out of the Crater: Chronicles of a Volcanologist, Richard V. Fisher, Princeton University Press, 1999

Saturday, February 26, 2011

Booklist: Out of the Crater, by Richard Fisher


Out of the Crater: Chronicles of a Volcanologist, by Richard V. Fisher
Princeton University Press, 1999
172 pages plus glossary and index
Library: 551.21 FIS


Description
Volcanologists venture to treacherous volcanoes the world over in the pursuit of their science. THey work around craters of boiling magma and amidst smoke, flames, scorched rocks and clouds of noxious gases - balancing personal risk against advancing knowledge about one of of nature's most dangerous and unpredictable forces.

Richard Fisher, a world-renowned volcanologist, has had more than forty years of experience in the field. In this book, he blends autobiogrpahy with clear, accessible science to introduce readers to the basics of volcanology and to the wonders of volcanoes that he has studied and learned to both fear and admire.

In the course of the book, we follow Fisher as he descends into the steaming hot crater of the Soufriere Volcano on the island of St. Vincent, as he conducts research on lava flows on the desolate south shore of the island of Hawaii, and as he struggles to understand the explosion at Mount St. Helens. We learn about his pioneering work on pyroclastic flows and surges-the hurricanes of gases, molten lava, and volcanic debris that cause most of the death and destruction when volcanoes explode.

HE tells of solving a historic scientific problem at Mount Pelee, Martinique, where 29,000 people were killed in a pyroclastic flow in 1902. Fisher also offers a volcanologist's view of the explosion of Mount Vesuvius that devastated Pompeii and Herculaneum. He writes about the cultural rewards and challenges of conducting research in isolated areas of such countries as Argentina, Mexico and China. And he discusses the early influences that steered him toward volcanology-including his army experiences as a witness to two atom-bomb explosions at Bikini atoll.

Out of the Crater is written in an inviting, nontechnical style. With its deft combination of personal stories and scientific information, it is an inspiring account of a remarkable life and a compelling examination of some of the most spectacular forces shaping the face of the earth.

Table of Contents
Acknowledgments
Prologue
1. Los Alamos, New Mexico
2. Bikini and the Atom Bomb
3. The Beginnings of a Career
4. Central Oregon: Tuff, Fossils and Lava
5. Puu Hou, Hawaii: Solitary Isolation
6. Volcanoes and Water
7. Mounrt Pelee, Martinique
8. Soufriere, St. Vincent
9. Volcanoes in Europe
10. Mount St. Helens
11. Mount Vesuvius
12. El Chichon, Southern Mexico
13. Calderas
14. Communist China
15. Italy and Ignimbrite
Epilogue
Glossary
Index

Booklist:

Friday, February 25, 2011

Volcano eruptions cause prices to rise

Telegraph.co.uk, from Rossiyskaya Gazeta: Volcano eruptions cause prices to rise

Violent eruptions along Russia’s volcano belt are affecting global weather patterns and prices to boot.

If you want to know where the especially harsh winter weather came from, look no further than Russia - and prepare to pay more for your flour and coal this year.

Volcanoes on the country’s eastern seaboard of Kamchatka have been unusually active for the last six months. The dust they threw up diverted winds in the Arctic, pushing cold air over Europe and North America and causing the unusually cold winter, say scientists.

This string of volcanoes, 29 of which are active, could cause more problems this year, depressing harvests around the globe just as food prices soar, and culminating in a second freezing winter.

The eruptions have come at the worst possible time. The Pacific Ocean has already been cooled by the “La Niña” ocean/atmosphere phenomenon, which is particularly severe this year. At the same time the Atlantic Ocean is warmer than usual.

Erste Bank said the combination of these factors means the weather forecast for the first quarter of 2011 is extreme, and will hit both the agricultural and mining sectors, sending spiking prices up even faster. “These climatic conditions reduce the outlooks of harvests for agricultural commodities and prevent the mining of commodities like coal. The extreme weather will probably culminate in the second quarter of 2011 . . . the prices of commodities will be influenced . . . then [we will see] an acceleration of consumer inflation.”

The combination shifts wind patterns around the world, but the spanner in the works has been the Kamchatka volcanoes, according to US climatologist Evelyn Browning-Garriss’s acclaimed Browning Newsletter: “Kamchatka tends to be active but recently it has been ridiculous! Since late November, Kizimen, Sheveluch, Karymsky, and Kliuchevskoi have been erupting almost constantly.”

Volcanic ash screens out the sun, cooling the air below. This lowers air pressures, which changes wind patterns, especially in the Arctic. And, “the cold air normally trapped around the North Pole surges south”. The upshot has been some bizarre weather. The UK was colder than Russia on Christmas Day and New York was under heavy snow, while Moscow had icy rain as temperatures hovered around zero.

The snap has already impacted agriculture. Australia’s wheat crop was down by 10pc in December – the worst fall in 100 years – and Russia’s agriculture ministry is forecasting a mediocre harvest. Add in last season’s severe drought in Argentina, floods in Brazil and Venezuela, odd weather in agricultural parts of China, and food prices have soared.

What happens throughout the rest of this year will 
depend entirely on the 
 volcanic activity, says Ms Browning-Garriss, which is impossible to predict.

Mud volcano to continue erupting for 26 years

TG Daily: Mud volcano to continue erupting for 26 years

The world's largest mud volcano looks set to continue erupting for another 26 years. Lusi, in Indonesia, first blew in 2006, killing about 15 people and rendering thousands of families homeless. More than a dozen villages have been swallowed up.

It's believed to have been caused by the blowout of a natural gas well nearby - although the Indinesian authorities have linked it to an earthquake that struck about 174 miles away a few days earlier.

Since then, it's continued to spew out mud at up to a million cubic feet per day - about five billion cubic feet in total.

And it's not going to stop any time soon, according to scientists at Durham University and Perth's Curtin University. The team's developed a new model using pressure readings from a nearby borehole and data on water sources and the local soil and rock structure.

And they reckon that it'll take more than a quarter of a century for the flow to fall by 90 percent. "By analogy with natural mud volcanoes, it can be expected to continue to flow at lower rates for thousands of years," say the authors.

It's even possible, they say, that the mud could be being replenished by another underground source, in which case it could carry on at its current rate for a hundred years.

In a report in the Journal of the Geological Society, the authors say that subsidence is causing new vents to open - and that over the 26 year period the ground level could drop by another 95 to 475 meters. Many of the existing 167 vents are spewing out dangerous gases, and some of these have ignited.

The immediate area is likely to be uninhabitable for a very long time.

Wednesday, February 23, 2011

How do volcanoes affect the climate?

The Guardian.co.uk:How do volcanoes affect the climate?

When volcanoes erupt, they emit a mixture of gases and particles into the air. Some of them, such as ash and sulphur dioxide, have a cooling effect, because they (or the substances they cause) reflect sunlight away from the earth. Others, such as CO2, cause warming by adding to the the greenhouse effect.

The cooling influence is particularly marked in the case of large eruptions able to blast sun-blocking particles all the way up to the stratosphere – such as Mount Pinatubo in 1991, which caused a significant dip in global temperatures in the following year or two. It's difficult to know for sure that the cooling observed after a particular eruption is definitely the result of that eruption, but examining the average global temperature change after multiple eruptions proves a strong link.

As for greenhouse gases, underwater and land-based volcanoes are estimated to release, in total, around 100–300 million tonnes of CO2 each year, according to the British Geological Survey and the US Geological Survey. That's a large quantity, but only around 1% of the amount that humans release from burning fossil fuel alone.

As a rule, the cooling influence of an individual volcano will dominate for the period immediately after the eruption but the warming impact will last much longer. So the significance of each depends on the timeframe being considered. A very large volcano in 2011 may significantly reduce temperatures in 2012 but slightly warm them in 2100.

It has sometimes been suggested by those who seek to disprove human impact on the climate that volcanoes release more CO2 than human activity. This is simply incorrect. As the British Geological Survey puts it:

"The contribution to the present day atmospheric CO2 loading from volcanic emissions is … relatively insignificant."

Hawaii revises volcano SO2 advisory for Big Island

Big Island Video News: Hawaii revises volcano SO2 advisory for Big Island
HONOLULU – In response to EPA’s new 1-hour sulfur dioxide (SO2) standard of 75 ppb, the Hawai‘i State Department of Health (DOH) has revised its advisory levels to be more protective of people with asthma.

The new advisory levels can be found on the website: http://www.hiso2index.info/ where the public can obtain up-to-date information on sulfur dioxide levels in areas of the Island of Hawaii impacted by vog and volcanic emissions. The public is encouraged to use the website to access near-time sulfur dioxide levels in the Pahala, Ocean View, Hilo, Mountain View, Puna, and Kona areas and in Hawai‘i Volcanoes National Park.

Sulfur dioxide is an irritant gas emitted by the Kilauea volcano. People with asthma, who are physically active outdoors, are most likely to experience the health effects of sulfur dioxide.

In 2008, the DOH collaborated with several federal and state agencies to develop a color-coded system to make it easier for people to understand quickly whether sulfur dioxide is reaching unhealthy levels in their communities. Six colors cover current sulfur dioxide levels measured by DOH air monitors based on 15-minute averages. The six colors correspond to different levels of health concern ranging from “good” to “hazardous”. Now, based on updated health effects information by the EPA, the DOH is revising the SO2 advisory levels for the Green-“Good,” Yellow –“Moderate” and Orange-“Unhealthy for Sensitive Individuals”

The revised DOH advisory levels of SO2 are aligned with the new national standard, said Gary Gill, Deputy Director for Environmental Health. “We still caution the public to rely on how they personally respond to SO2 in the air and not just on the DOH air monitors to make decisions.”

The sulfur dioxide effect on communities varies widely depending largely on the wind and weather conditions. Accordingly, the stationary air monitors may not be representative of sulfur dioxide levels in your own community. For more information, contact the Clean Air Branch (808) 586-4200.

Tuesday, February 22, 2011

Two US volcanoes making news: Kilauea and St. Helens

Think Big: Two US volcanoes making news: Kilauea and St. Helens
This article was published on Feb 16, 2011.
Erik Klemetti on February 16, 2011, 8:54 AM

Hawai`i: The lava lake at the Halema`uma`u Crater in Kilauea has reached new heights - in fact, the lava lake had gotten high enough (~77 meters below the crater floor) in the pit crater that there was some thoughts that it might spill out onto the floor of the crater. However, that fate is unclear now as the pit crater itself is collapsing into the lava lake, with large chunks of the rim falling in on Monday. These chunks, some as large as 120 meters x 5 meters, fell into the lake and produced small plumes of ash and gases along with very obvious popping sounds heard as far as half a mile away.

You can hear some of the noises and watch some quicktime movies of the activity at the Halema`uma`u Crater over on the Hawaii Volcano Observatory website. Collapses in the pit crater in 2009 blocked off the lava lake from view, but quickly the lava was able to retake the crater. Seismicity related to the upper east rift zone of lava seemed to peak late last week, which might suggest that the influx of new basaltic magma might be waning. Be sure to check out the great time lapse videos (this one from Pu`u O`o) from Eruptions readers along with all the Kilauea the webcams as well. UPDATE: Speaking of Pu`u O`o time lapse video, here is a new one from the USGS as well.

Washington: Back in the continental United States, the earthquake swarm underneath Mount St. Helens appears to be continuing, albeit in a bit of a sporadic fashion. A magnitude 4.3 earthquake occurred ~10 km to the north of the crater on Monday and along with a number of smaller aftershocks, were all located at ~4-7 km depth. The USGS is, not surprisingly, keeping an eye on these earthquakes but the indications don't seem to be pointing to any impending eruption at St. Helens. The earthquake, the largest in 30 years at the volcano, was large enough to be felt by some people in the area near the volcano and in Portland (thus all the horrible "Love waves on Love Day" puns - Love waves are the side-to-side surface waves in an earthquake). Dr. Bill Steele of the University of Washington Geophysics Lab said that this swarm is not unexpected in the area but it is "awfully vigorous" and that this seismicity might be related to changes in the stress field near St. Helens. These changes are usually associated with moment of magma or cooling of magma under the edifice.

Philippine scientists warn of more explosions at restive volcano

M&C: Philippine scientists warn of more explosions at restive volcano

Manila - Philippine scientists on Tuesday warned of more explosions from a restive volcano that has been spewing ash for two days after nearly three months of inactivity.

More than 100,000 people were affected by Monday's two ash explosions at Mount Bulusan volcano in Sorsogon province, 250 kilometres south-east of Manila.

At least 2,000 were forced to flee their homes in three towns at the foot of Mount Bulusan, according to civil defence authorities.

The Philippine Institute of Volcanology and Seismology said it had recorded 16 volcanic earthquakes since the ash explosions started Monday.

'Entry to the 4-kilometre radius permanent danger zone is strictly prohibited since the area is at risk of sudden steam and ash explosions,' the institute warned.

'Civil and aviation authorities must also warn pilots to avoid flying close to the volcano's summit,' it added.

Mount Bulusan is one of the country's 23 active volcanoes. Its last eruption was in 2006, when no one was hurt.

Sunday, February 20, 2011

Hundreds of villagers flee as Philippine volcano belches ash and smoke

Winnipeg Free Press: Hundreds of villagers flee as Philippine volcano belches ash and smoke

MANILA, Philippines - Hundreds of villagers fled to safety Monday after a restive volcano belched ash and smoke into the sky after a monthlong lull, officials said.

Despite Mount Bulusan's ash explosion, its 13th since November, there were no signs of an imminent eruption involving magma pushing out of the cone, said government chief volcanologist Renato Solidum.

The huge plume of greyish smoke shot up to more than a mile (2 kilometres) toward the blue sky, with the ash drifting southwest toward four farming towns in Sorsogon province, where about 1,200 villagers fled to emergency shelters and houses of relatives, said Benito Ramos, who heads the government's disaster-response agency.

Army trucks helped villagers move from communities hit by the ashfall and emergency teams handed out protective masks, Ramos said.

There have not been any government orders to evacuate communities near the mountain. While many scrambled to safety, residents streamed out of houses in Irosin town to gaze or take pictures of the mid-morning spectacle using their cellphones.

Still-hot debris at the peak of Bulusan, one of the country's 23 active volcanoes, came into contact with water, sparking the explosion. Such steam-driven blasts have happened since November and could continue in coming weeks, Solidum said.

Bulusan lies about 240 miles (380 kilometres) southeast of Manila.

Thursday, February 17, 2011

VIDEO: Explosive volcano rim collapse filmed by USGS

Big Island Video Newsroom: VIDEO: Explosive volcano rim collapse filmed by USGS
(See video at link above)

The Hawaiian Volcano Observatory reports that at 8:42 a.m. on Monday morning, a section of rock from the north wall of Kilauea Volcano’s summit vent broke away, and collapsed into the lava lake below. Moments later, gas and ash were explosively ejected from Halema‘uma‘u, as this dusty-brown plume shot skyward from the crater.

About three hours later, another, larger crescent-shaped piece of the vent rim plummeted into the lava. The rock was estimated to be about 395 ft long and up to 16 ft wide. Shortly thereafter, the lava lake level began to drop. It continued to fall throughout the day, but rose again overnight.

The event had been forecast by the Hawaiian Volcano Observatory geologists, mainly because that part of the vent rim was overhung by about 180 ft. Rocks falling from this overhang have been a common occurrence, but spattering episodes and the intense heat of the rising lava lake has increased the number of collapses over the past few weeks.

On Monday, blocks of rock hitting the surface of the lava lake created sharp popping sounds that could be heard by visitors at the Jaggar Museum Overlook in Hawai‘i Volcanoes National Park. The churning lava lake within the summit vent also produced a sound likened to crashing waves. Geologists were able to make this recording of these sounds, which were posted to the HVO website.

The continued extension across the summit area, as well as numerous earthquakes, suggests that the volume of magma at the summit has increased, according to Jim Kauahikaua, HVO Scientist-in-Charge.

A recent overflight above Halemaumau showed a rising lava surface, at this point as little as 98 yards below the floor of the crater.

Meanwhile, further down along the east rift zone, the volcanic display at Pu’u O’o is no less impressive.

The USGS filmed this footage between February 6-8. Scientists say lava has been erupting sporadically from three vents within Pu`u `Ō `ō crater-a cone on the west side of the crater floor (in this video, that is in the foreground to left), a cone on the northeast side – here in the center frame – and from an opening on the east crater wall seen in the background.

Unlike the Upper East Rift Zone a few days ago, seismic tremor levels uprift of Pu`u `O`o remained low and steady. The most recent sulfur dioxide emission rate measurement from east rift zone vents was 300 tonnes/day.

Remember, daily updates about Kilauea’s ongoing eruptions, recent images and videos of summit and east rift zone volcanic activity, and data about recent earthquakes are posted on the HVO Web site at hvo.wr.usgs.gov.

Volcano Drilling Team Get Magma Surprise at Iceland Volcano

Our Amazing Planet: Volcano Drilling Team Get Magma Surprise at Iceland Volcano
Geologists drilling an exploratory geothermal well into a volcano in Iceland got quite a surprise when the borehole filled with molten magma forcing the researchers to halt the drilling.

However, the sudden appearance of the molten rock wasn't all bad, according to Wilfred Elders, a professor emeritus of geology at the University of California, Riverside, who led the research team that was drilling into the Krafla volcano in 2009.

Roughly 95 percent of home heating and one-third of electric power in Iceland comes from geothermal sources — from steam and hot water that occurs naturally in volcanic rocks — and the team was investigating new ways to harness geothermal energy.

"We were drilling a well that was designed to search for very deep geothermal resources in the volcano. While the magma flow interrupted our project, it gave us a unique opportunity to study the magma and test a very hot geothermal system as an energy source," Elders said in a statement.

The team was planning to drill 2.7 miles (4.5 kilometers) into the volcano, but had to stop at 1.3 miles (2.1 km) when the magma began to flow into the borehole.

Elders and colleagues report in the March issue of the journal Geology that although the Krafla volcano, like all other volcanoes in Iceland, is basaltic (a volcanic rock containing 45 to 50 percent silica), the magma they encountered is a rhyolite (a volcanic rock containing 65 to 70 percent silica).

"Our analyses show that this magma formed by partial melting of certain basalts within the Krafla volcano," Elders said.

This is a view of the Krafla volcano, Iceland, across the explosion crater Viti that erupted in 1787, showing the drilling rig. The borehole encountered molten rock at 6,500 feet depth. Credit: G.O. Fridleifsson.

"The occurrence of minor amounts of rhyolite in some basalt volcanoes has always been something of a puzzle," Elders said. "It had been inferred that some unknown process in the source area of magmas, in the mantle deep below the crust of the Earth, allows some silica-rich rhyolite melt to form in addition to the dominant silica-poor basalt magma."

Elders explained that in geothermal systems, water reacts with and alters the composition of the rocks, a process called "hydrothermal alteration."

"Our research shows that the rhyolite formed when a mantle-derived basaltic magma encountered hydrothermally altered basalt, and partially melted and assimilated that rock," Elders said.

Elders believes it should be possible to find reasonably shallow bodies of magma, elsewhere in Iceland and the world, wherever young volcanic rocks occur.

"In the future, these could become attractive sources of high-grade energy," Elders said.

Monday, February 14, 2011

VOLCANO WATCH: “What’s in a name?”

Big Island video news: VOLCANO WATCH: “What’s in a name?”

“That which we call a rose by any other name would smell as sweet.” The Kilauea version of this Shakespeare quote could be “That which we call an explosive eruption by any other name would still be just as hot!”

An important part of HVO’s mission is to document the activities of Hawaiian volcanoes. In order to do that well, we sometimes need to name processes or structures in order to make it easier to describe other aspects of their activity. For example, we can save a lot of text by calling flows either pahoehoe or `a`a instead of describing them each time.

The explosive expulsion of rocks and spatter from the Halema`uma`u vent since mid-March 2008, seemed to be an obvious explosive eruption at first. The intermittent glow and the discovery of small bits of spatter on the rim of Halema`uma`u Crater suggested the presence of lava deep down in the vent, but it wasn’t actually seen until September of that year.

Between March and the end of 2008, there were several more explosive events, but it was also clear that a lava lake existed within the Halema`uma`u vent, making this a continuous eruption punctuated by explosive expulsion of spatter and chunks of the vent wall.

The products of these explosive events looked like those of other explosive eruptions—a mixture of rock dust and chunks and bits of fresh spatter in the form of Pele’s tears and hair and a variety of other geometric forms. But what exactly was making the lava lake explode?

Establishment of several Webcams tracking developments in Halema`uma`u Crater allowed scientists to safely witness the events that preceded several explosive events. They found that many were triggered by vent wall collapses, that is, portions of the wall would collapse and rain down on the lava lake. This would initiate vigorous degassing—enough to eject gas, bits of lava from the lake, and fragments of the wall rocks that appeared to explode out of the narrow vent.

From the first explosive event, our colleagues at the Infrasound Laboratory of the University of Hawai`i (ISLA) pointed out that atmospheric pressure variations caused by the Halema`uma`u “explosive” events did not match those from other explosive eruptions.

Truly explosive eruptions produce an excess atmospheric pressure that sometimes hurt observers’ ears. For example, the explosive eruptions of Halema`uma`u in 1924 were immediately preceded by concussions painful to the ears. The 2008-2010 Halema`uma`u events produced an initial drop in atmospheric pressure, followed by a rapid increase—the increase being associated with the forceful ejection of solid rocks and spatter out of the vent. The drop in atmospheric pressure could be associated with the rocks hitting the lava lake, followed by the pressure increase as the gases explosively expanded. They differentiated these from those initiated by excess pressure by calling them “degassing bursts.”

The recent Halema`uma`u explosive events are triggered in a different way than other explosive eruptions. Normally, volcanoes explode when the strength of the volcano is no longer capable of containing the internal magmatic pressure. When the volcano fails, gases dissolved in the magma are able to expand explosively ejecting debris to potentially great heights and great distances. Another way that an explosive eruption can be triggered is the introduction of water into a hot volcano’s interior. Upon contact with molten magma, the water can explosively flash to steam as is thought to have driven the May 1924 explosive eruptions of Kilauea. Neither of these two traditional processes are triggering the recent explosive events at Halema`uma`u.

HVO discoveries have highlighted a third way that explosive eruptions are triggered in lava lakes. Rock falls from vent walls must cause the release of a small amount of built-up gas pressure beneath the lava lake crust, resulting in small explosive releases. These explosive events will probably never be as large or as hazardous as those triggered in other ways.

So what’s in a name? To paraphrase Shakespeare geologically-speaking, “That which we call an explosive eruption or a degassing burst would still produce the same rock deposits.”

Warning of new Icelandic volcano eruption

Travel Weekly: Warning of new Icelandic volcano eruption
The travel industry could face a re-run of last year’s Icelandic ash cloud crisis as a larger volcano next to the one that erupted last year looks set to blow.

Geologists monitoring seismic activity around Bárdarbunga, the island’s second largest volcano, last week warned there was “every reason to worry” that an eruption was going to happen.

Last year the eruption of the Eyjafjallajökull volcano caused the closure of British and European airspace on three separate occasions grounding flights and causing multi-million pound losses for airlines and tour operators.

Although last year’s crisis forced the government to agree new safety standards, there are fears that any eruption this year could plunge the industry into the same situation.

Francesa Ecsery, Cheapflights global sales director, said: “My concern is we have not done our homework on volcanic ash.

“Last year it closed down the airspace, but that can’t possibly be the answer. I’m worried we have not used the time properly between last year and now to examine this and the next time this happens we are going to have an issue.”

Ecsery said the UK should have experts in part of the world that regularly have to cope with this problem to devise a plan that will allow UK airspace to remain open in the event of another eruption sending ash towards Britain.

The British government faced criticism from some in the airline industry over the way it handled last year’s ash crisis with some saying it was an over-reaction.
But the CAA, the safety body that overseas air transport insisted it was acting in the best interests of air passengers.

A CAA spokesman said: "Aviation is in a better place to respond to volcanic ash than in April last year. In the last six months a huge amount of work has been done to improve our ability to safely mitigate disruption from ash.

"Of course there is still more work to be done with the international aviation industry to further improve the situation. However, in the exceptional circumstance that there is an eruption, with dense ash and the weather is unfavourable, while we will all try to reduce disruption, we will put safety first. "

The last recorded eruption of Bárdarbunga was in 1910, although this was minor in comparison to the last major eruption in 1477. The volcano is responsible for the largest lava flow on the planet in the last 10,000 years.

The Highest Volcano in the Sahara


Our Amazing Planet: The Highest Volcano in the Sahara

The broad Emi Koussi volcano, as seen in this astronaut photograph is a shield volcano located in northern Chad, at the southeastern end of the Tibesti Range.

The dark volcanic rocks of the volcano provide a sharp contrast to the underlying tan and light brown sandstone exposed to the west, south and east (image lower left, lower right and upper right).

Emi Koussi was formed from relatively low viscosity lavas — flowing more like motor oil than toothpaste — and explosively-erupted ignimbrites (rapid flows of hot volcanic material dominated by pumice, a light, porous volcanic rock) that produce a characteristic low and broad structure covering a wide area (approximately 37 by 50 miles, or 60 by 80 kilometers).

At 11,204 feet (3,415 meters) above sea level, Emi Koussi is the highest summit of Africa's Sahara region. The summit includes three calderas (volcanic craters) formed by powerful eruptions.

Two older and overlapping calderas form a depression approximately 7.5 by 9.3 miles (12 kilometers by 15 kilometers) in area bounded by a distinct rim (image center). The youngest and smallest caldera, Era Kohor, formed as a result of eruptive activity within the past 2 million years.

Young volcanic features, including lava flows and scoria cones (also called cinder cones) are also thought to be less than 2 million years old. There are no historical records of eruptions at Emi Koussi, but there is an active thermal area on the southern flank of the volcano, according to a NASA statement.

Activity at Shiveluch Volcano


Earth Observatory: Activity at Shiveluch Volcano

With a summit that reaches 3,283 meters (10,771 feet), Shiveluch is one of the largest and most active volcanoes in Russia’s Kamchatka Peninsula. At least 60 large eruptions of Shiveluch have occurred during the past 10,000 years, making it the most vigorous volcano of the Kuril-Kamchatka volcanic arc.

On January 25, 2011, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite detected a hot avalanche of volcanic debris—a pyroclastic flow—sliding down the south side of the volcano. This image shows the flow’s heat signature as measured in thermal infrared light. The white area at the lava dome is very hot, while the red areas on the edge of the flow are just warmer than the surrounding snow.

The hot trail of material descending to the south forms a large distributed deposit, indicating a recent collapse of the lava dome and formation of a large debris avalanche. According to the Global Volcanism Program, Shiveluch’s current eruptive period began in 1999.

References
Global Volcanism Program. (n.d.) Shiveluch. Smithsonian Institution, National Museum of Natural History. Accessed February 10, 2011.
Photojournal. (2011, January 27). NASA spacecraft captures fury of Russian volcano. NASA Jet Propulsion Laboratory. Accessed February 10, 2011.

Thursday, February 10, 2011

Huge volcano under Yellowstone Park rising

Science on MSNBC.com: Huge volcano under Yellowstone Park rising
By Brett Israel
OurAmazingPlanet OurAmazingPlanet
updated 2/9/2011 2:06:01 PM ET 2011-02-09T19:06:01
Share Print Font: + - The huge volcano under Yellowstone National Park has been rising at an unprecedented rate during the past several years, according to a new study.

In the ancient past, the Yellowstone volcano produced some of the biggest-known continental eruptions, but the recent rising doesn't mean another doomsday eruption is looming, scientists say.

The recent rising is unprecedented for Yellowstone's caldera — the cauldron-shaped part of the volcano — but it's not uncommon for other volcanoes around the world. The new study has simply revealed a more active caldera at Yellowstone than scientists realized.

"It's pretty exciting when you see something that's five times larger than what you've seen in the past," said Charles Meertens, director of the nonprofit UNAVCO facility in Boulder, Colo., which aids geoscience research. Meertens is a former postdoctoral fellow under one of the study's authors, Robert Smith of the University of Utah in Salt Lake City.

In 2004, the caldera was swelling at 2.8 inches a year in some parts, but the uplift has since slowed to a low of 0.2 inches a year, according to the study, which was published in the December edition of the journal Geophysical Research Letters.

Calderas rise just like an inflating bubble. The inflating could either be caused by magma rising and pushing up on the caldera, or the magma could be heating gases and hydrothermal fluids (the same fluids that spew from Yellowstone's Old Faithful geyser) and pushing them against the caldera, Meertens told OurAmazingPlanet. Whatever the exact mechanism, a rising caldera is not enough to signal an eruption.

"It's not a portent of doom," said Erik Klemetti, a volcanologist at Denison University in Granville, Ohio, who was not involved with the study. "It seems like these restless calderas are always sort of rising and falling, but that by itself doesn't mean it's about to erupt."

Volcanologists look at several indicators when deciding whether an eruption is looming, Klemetti said. Warning signs typically include an increase in earthquakes under the volcano, changes in the gases being emitted, change in the volcano's shape, and steam and heat escaping from the top.





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This blog is updated - at a minimum - every Monday and Friday

Iceland volcano professor hits back at eruption scare stories

Ice News: Iceland volcano professor hits back at eruption scare stories
The Icelandic geophysicist, Professor Pall Einarsson, whose words have caused something of an international volcano scare, says he is dumbfounded by how much his message has changed in translation. Pall Einarsson was interviewed by Icelandic broadcaster RUV in Icelandic about a series of earthquakes in the highlands.The interview was then translated and used by Britain’s Daily Telegraph, among others. Since then the message has morphed out of all recognition, Einarsson says.

“It is really strange how this news came into existence. I wasn’t even warning of a likely eruption at Bardarbunga [in the interview],” he told IceNews. “The things I emphasised in my interview with RUV’s Bjorn Malmqvist were that the earthquakes at Bardarbunga and Kistufell last week are not unusual, there are often movements there, and sometimes much bigger than this.

“In the long-term, we can see an increase in earthquake intensity at Bardarbunga. But it is still a lot less than between 1974 and 1996.

“And finally that Bardarbunga is an active volcano and could of course prove dangerous, which is why there is always reason to monitor it closely; which is why we do,” Einarsson explains.



Some foreign media sources have quoted Professor Pall Einarsson as saying that a massive eruption is about to begin that will make last year’s Eyjafjallajokull eruption seem tiny in comparison. The professor reiterates his confusion at such stories, telling IceNews that he did not say anything of the sort.

Volcanic eruptions are always possible in Iceland, Einarsson says. There have been at least 19 eruptions in just the last 40 years — the majority of which were small and caused very little damage.

Icelandic volcanoes are one of the reasons tourists visit the country and sometimes (as at Fimmvorduhals last year) the sheer number of visitors is more dangerous than the volcano itself. “There are few things more moving than to watch a volcano erupting from a safe distance,” Professor Einarsson enthuses.

Bardarbunga is located near the middle of the Icelandic ‘hot belt’. It was, however, not known as a particularly powerful volcano before 1971 when the first satellite images of the area were released. Eruptions connected to this particular volcanic system took place in 1477-80, shortly after 1700, 1862-4 and most recently in 1996. There are probably several historic eruptions missing from the list due to the sheer distance from the nearest human settlements, the professor adds. “Small eruptions at this remote volcano could easily have escaped people’s notice. They are no more dangerous than that.”
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This blog is updated - at a minimum - every Monday and Friday

Tuesday, February 8, 2011

Tuesday Tidbits: Taiwanese volcanoes, Terraces for sale, Erebus ice and more

BigThink: Tuesday Tidbits: Taiwanese volcanoes, Terraces for sale, Erebus ice and more

Happy Birthday to Jules Verne, even though traveling to the center of the Earth via Snæfellsjökull (and exiting via Stromboli) might not be the best idea.

Some news for February 8, 2011:

Taiwan: Most people don't realize that the island of Taiwan has potentially active volcanoes. One such volcanic center is the Datun (as known as Tatun) Group, a series of domes that are believed to have last erupted in ~4,100 BC and the current manifestation of the magmatism are hot springs and solfatara. The National Science Council of Taiwan will be setting up volcano monitoring system for the Tatun Group - seismometers and tiltmeters it appears - and the data sounds like it might be readily available online when the installation is complete.

New Zealand: Well, after all the excitement over the (re)discovery of the Pink Terraces in Lake Rotomahana - thought lost after the 1886 eruption of Tarawera - it seems that humans can't stand not making money. A fellow in New Zealand is selling what he claims is a vial of pre-destruction terrace and the bidding for the vial is already up to, if you can believe it, ~$1.1 million (NZ - approximately $847,000 US). Now, there is a lot of question of the authenticity of the sample but in New Zealand, it is legal to sell such relics, so as always, buyer beware!

Yellowstone: The caldera in Wyoming is still making the news, even if they are still talking to quacks about it.

Antarctica: In a little bit of eye candy, there is a set of images taken from the ice caves on Mt. Erebus in Antarctica, the most southerly active volcano (that we know of) on the planet. Some pretty stunning ice, including layer of ash from Erebus locked into the deep freeze. Ice caves are common on active volcanoes (with ice on them) thanks to the abundant heat and you can find them in places less remote than Antarctica, such as Washington's Mt. Baker.



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This blog is updated - at a minimum - every Monday and Friday

Ice volcanoes are all the rage this winter

Yahoo News: Ice volcanoes are all the rage this winter
How do you stimulate a regional tourist economy in the dead of a blizzard-battered winter? Simple: ice volcanoes!

The cone-shaped ice formations—known as cryovolcanoes in scientific circles—afford hardy winter adventurers with cozy, igloo-type shelter as they trek on the frozen surface of a body of water. And ice volcanoes are emerging as a key tourist draw on the frozen surface of the Great Lakes region this winter.

As the Milwaukee Journal Sentinel reports, many people are now scouring the bleak winterscape of the Great Lakes in February for an ice volcano of their very own. The paper reports that "winter enthusiasts" have been "flocking to Bradford Beach, the Doctors Park beach and other spots along the Lake Michigan shoreline since last week's blizzard to check out a bizarre lunar landscape of craters, boulders and rounded mounds carved from the shoreline ice shelf by wind and waves."

"It's pretty cozy in here; I'm not going to lie," Marna Lamson of Milwaukee told the paper after she huddled inside one such formation for a while. "It's very sheltered from the elements. The bottom is snow and ice."

So what exactly is an ice volcano? According to the Weather Notebook's Byron Yeaton, they're "water-spouting ice cones" that form during the winter along the Great Lakes. Geologists at Michigan Technical University maintain a website chronicling the ice volcanoes along the shoreline of Lake Superior. Here's their own expert account of how ice volcanoes come into being: "Cones begin to form at the leading edge of the ice shelf as it builds out into the lake. When the waves, driven by strong onshore winds, feel bottom they build and break onto the ice shelf. After the ice shelf has built out, waves continue to travel underneath the ice and are forced up through cracks and previously formed cones."

Nor are the exotic cold-weather confined to our own humble planet. Space explorers have spotted ice volcanoes on several of the more icy moons in our solar system, including most recently on Saturn's Titan moon. Below is a video detailing the find by NASA's Cassini spacecraft:


And there, it seems, is the perfect ad campaign for the Great Lakes tourism board: Why go to the moons of Saturn to behold the grandeur of an ice volcano, when you can just go to Wisconsin?




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This blog is updated - at a minimum - every Monday and Friday

Sunday, February 6, 2011

From Feb 3: Volcano Made Famous By 007 Menaces Japan Island

NPR: Volcano Made Famous By 007 Menaces Japan Island
In the James Bond version, circa 1967, Japan's Mount Shinmoe was a serene, extinct peak with a scenic, lake-filled crater that provided the perfect perch for 007 and his bikini-clad partner to surveil the lair of supervillain Ernst Stavro Blofeld.

In real life, it turns out the volcano doesn't have a secret rocket base hidden in its depths as it did in You Only Live Twice.

It's also not extinct.

In its biggest series of eruptions in 52 years, Mount Shinmoe burst back to life last week and is wreaking havoc with airline schedules, forcing schools and roads to close and dumping ash and rocks across towns on Kyushu, the southernmost of Japan's four main islands.

On Thursday, the volcano spewed a huge plume one mile (1,500 meters) into the air and sent rubble cascading down its forested slopes. Officials say they expect the eruptions to continue, and possibly intensify, for weeks to come.

"We really have no idea how long this is going to go on," said Tomoharu Konan, a town official in Takaharu, which lies at the foot of the volcano. "We got a lot of ash in the first several days, and it covered our farms. We will have to make long term plans for how to deal with this situation."

To keep the curious out, a danger zone around Shinmoe has been widened to a radius of 2 1/2 miles (four kilometers) from its crater. Local officials said the mountain is remote enough to keep that from being much of an issue — only two small lodges are located in the no-access area.

No significant injuries have been reported since the initial eruption last Wednesday, though a 92-year-old woman reportedly suffered cuts from shattered glass when a window was smashed in a pulse of air from a subsequent eruption.

Disruptions to travel have been a bigger problem.

Dozens of domestic flights in and out of Miyazaki — a city of 365,000 about 590 miles (950 kilometers) southwest of Tokyo — were grounded last week. Though some flights had been restored, airport officials said ash on the ground and in the air forced more cancellations Thursday. Volcanic ash advisories were in effect for the area, according to the Japan Meteorological Agency.

Train service was temporarily suspended in the area and many schools closed, and the local government has reported damage to crops and cattle.

Officials in Takaharu, which has a population of 9,900, have urged about 1,100 residents who live near the volcano to go to evacuation centers because of the danger of debris, ash and landslides. The warning was not mandatory, however, and some residents were staying home.

Experts said a dome of lava was growing larger inside the 4,662-foot (1,421-meter) volcano's crater, but it was not certain whether the dome would grow enough to spill over the rim and create large flows down the volcano's sides.

Avalanches of superheated gas, ash and rock have already been observed, along with spectacular electrical storms within the volcano's plume.

The Japanese islands, located along the Pacific "Ring of Fire," are volcanic in origin and dozens of volcanos — including the picturesque Mount Fuji, about 60 miles (100 kilometers) from Tokyo — are in various stages of activity. Thirteen are in the highest, or "A," level of activity, according to the Geological Survey of Japan.

In 1991, 43 people died in the eruption of Mount Unzen, also on Kyushu island.

6 Feb, 2010: Aid workers ease volcano burden

Japan Times: Aid workers ease volcano burden
MIYAKONOJO, Miyazaki Pref. (Kyodo) An increasing number of aid workers, including some who helped out after the 1995 Great Hanshin Earthquake and the 2000 major eruption of Mount Miyake, are heading to Takaharu, Miyazaki Prefecture, near Japan's latest volcanic activity.



Straight from Shinmoe: A worker shovels volcanic ash from Mount Shinmoe on Saturday in Miyakonojo, Miyazaki Prefecture. KYODO PHOTO


The volunteers hope to use their experience to ease the anxiety of people forced out of their homes since Mount Shinmoe started erupting last month.

Many of the evacuees are elderly. Other residents who still remain home also have fears of possible avalanches triggered by the volcano.

Since the eruptions first occurred Jan. 19, an estimated 80 million tons of ash have fallen on a wide area, according to the Coordinating Committee for Prediction of Volcanic Eruptions under the Meteorological Agency.

The first batch of aid workers from a Kobe-based group will arrive in Takaharu on Monday. They plan to provide hot water for evacuees. Many of them haven't been able to bathe at their shelter.

Nobuyuki Kurita, 46, head of an aid group based in Nagoya, is arranging a similar hot-water service. He said this type of care is vital for displaced people.

People who have experienced volcanic eruptions, including people who lived near Mount Miyake off the Izu Peninsula and Mount Usu in Hokkaido, are arranging counseling services for the evacuees.

"In many cases, volcanic eruptions can drag on and on, weighing heavily on the lives of evacuees," said Kana Miyashita, 41, who organized aid workers with such experience.

Meanwhile, a central government team will be sent this week to Kagoshima and Miyazaki prefectures to work up a response plan.

On Saturday, the Liberal Democratic Party grabbed the opportunity to listen to local needs, with President Sadakazu Tanigaki visiting a shelter in Takaharu.

Wednesday, February 2, 2011

Picture of the Day: Japan's Shinmoedake Volcano Erupts


The Atlantic: Picture of the Day: Japan's Shinmoedake Volcano Erupts
Perhaps best known outside of Japan as the setting for the 1967 James Bond film, You Only Live Twice, Shinmoedake in Kagoshima Prefecture, Kyushu, is a volcano believed to have been formed tens of thousands of years ago. Beginning in 1716, eruptions have been observed nine times over the past three hundred years, but the most recent, which began on January 19, 2011, has been described by Reuters as the most active in that long history.

The photograph above, taken from the Takaharu Town Office where an evacuation advisory was issued this past Sunday evening, shows lightning originating from the 4,662-foot-tall volcano's central crater.