Thread: Massive volcano beneath Antarctic ice

Massive volcano beneath Antarctic ice

Monday, 21 January 2008
Agence France-Presse

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PARIS: A powerful volcano erupted under the icesheet of Antarctica around 2,000 years ago and it might still be active today, a finding which raises questions about ice loss from the white continent.

The explosive event – rated "severe" to "cataclysmic" on an international scale of volcanic force – punched a massive breach in the icesheet and spat out a plume some 12 kilometres into the sky, said British scientists behind the find.

Occasional volcanism

Most of Antarctica is seismically stable. But its western part lies on a rift in Earth's crust that gives rise to occasional volcanism and geothermal heat, occurring on the Antarctic coastal margins.

This is the first evidence for an eruption under the ice sheet itself – a slab of frozen water, hundreds of metres thick in places, that holds most of the world's stock of fresh water.

Reporting in the journal Nature Geoscience this week, the investigators from the British Antarctic Survey (BAS), In Cambridge, England, describe the finding as "unique."

It extends the range of known volcanism in Antarctica by some 500 km and raises the question whether this or other sub-glacial volcanoes may have melted so much ice that global sea levels were affected, they said.

The volcano, located in the Hudson Mountains, blew around 207 BC, give or take 240 years, according to their paper.

Anomalous radar readings

Evidence for this comes from a British-American airborne geophysical survey completed between 2004 and 2005. This used radar to delve deep under the ice sheet to map the terrain beneath. The team spotted anomalous radar reflections over 23,000 square kilometres - an area bigger than Wales.

They interpret this signal as being a thick layer of ash, rock and glass, formed from fused silica, that the volcano spewed out in its fury.

The amount of material – 0.31 cubic kilometres – indicates an eruption of between three and four on a yardstick called the Volcanic Explosive Index (VEI).

By comparison, the eruption of Mount St. Helens in 1980, which was greater, rates a VEI of five, and that of Mount Pinatubo in 1991 is a VEI of six.

Melting ice

"We believe this was the biggest eruption in Antarctica during the last 10,000 years," said lead author Hugh Corr. "It blew a substantial hole in the icesheet and generated a plume of ash and gas that rose around 12 km into the air."

The eruption occurred close to the massive Pine Island Glacier, an area where movement of glacial ice towards the sea has been accelerating alarmingly in recent decades.

"It may be possible that heat from the volcano has caused some of that acceleration," said co-author David Vaughan, who stresses though that global warming is by far still the most likely culprit.

Volcanic heat "cannot explain the more widespread thinning of West Antarctic glaciers that together are contributing nearly 0.2mm (0.008 of an inch) per year to sea-level rise," he adds. "This wider change most probably has its origin in warming ocean waters."
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ocean warming

Perhaps The Climate Change Models Are Wrong
Lorne Gunter, National Post
Published: Monday, March 24, 2008

Bob Strong, Reuters
They drift along in the worlds' oceans at a depth of 2,000 metres -- more than a mile deep -- constantly monitoring the temperature, salinity, pressure and velocity of the upper oceans.

Then, about once every 10 days, a bladder on the outside of these buoys inflates and raises them slowly to the surface gathering data about each strata of seawater they pass through. After an upward journey of nearly six hours, the Argo monitors bob on the waves while an onboard transmitter sends their information to a satellite that in turn retransmits it to several land-based research computers where it may be accessed by anyone who wishes to see it.

These 3,000 yellow sentinels --about the size and shape of a large fence post -- free-float the world's oceans, season in and season out, surfacing between 30 and 40 times a year, disgorging their findings, then submerging again for another fact-finding voyage.

It's fascinating to watch their progress online. (The URLs are too complex to reproduce here, but Google "Argo Buoy Movement" or "Argo Float Animation," and you will be directed to the links.)

When they were first deployed in 2003, the Argos were hailed for their ability to collect information on ocean conditions more precisely, at more places and greater depths and in more conditions than ever before. No longer would scientists have to rely on measurements mostly at the surface from older scientific buoys or inconsistent shipboard monitors.

So why are some scientists now beginning to question the buoys' findings? Because in five years, the little blighters have failed to detect any global warming. They are not reinforcing the scientific orthodoxy of the day, namely that man is causing the planet to warm dangerously. They are not proving the predetermined conclusions of their human masters. Therefore they, and not their masters' hypotheses, must be wrong.

In fact, "there has been a very slight cooling," according to a U.S. National Public Radio (NPR) interview with Josh Willis at NASA's Jet Propulsion Laboratory, a scientist who keeps close watch on the Argo findings.

Dr. Willis insisted the temperature drop was "not anything really significant." And I trust he's right. But can anyone imagine NASA or the National Oceanic and Atmospheric Administration (NOAA) or the Intergovernmental Panel on Climate Change -- the UN's climate experts -- shrugging off even a "very slight" warming.

A slight drop in the oceans' temperature over a period of five or six years probably is insignificant, just as a warming over such a short period would be. Yet if there had been a rise of any kind, even of the same slightness, rest assured this would be broadcast far and wide as yet another log on the global warming fire.

Just look how tenaciously some scientists are prepared to cling to the climate change dogma. "It may be that we are in a period of less rapid warming," Dr. Willis told NPR.

Yeah, you know, like when you put your car into reverse you are causing it to enter a period of less rapid forward motion. Or when I gain a few pounds I am in a period of less rapid weight loss.

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Submitted by Visitor on 27 March 2008 - 10:06am.
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conections?

now that we see a volcano with these possible results over time, maybe now we can connect this situation i learned about a few years ago. A Canadian scientist has discovered a lost city in the early 2000 off the coast of Cuba and has ruins under water they think predates the pyramids....see this link below.....i wondering if modern man is a lot older than what the bible says(6000 yrs)...you draw you own conclusions:

http://news.bbc.co.uk/1/hi/world/americas/1697038.stm

James Heroux
Canada
Submitted by Visitor on 27 March 2008 - 10:17am.
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Earth is a lot older. Read

Earth is a lot older. Read Genesis carefully. After Noah and the flood, God said replenish the earth. Replenish means to plenish again. Go to the part in the beginning about adam and eve. They were told to replenish the earth, meaning that there was something there before them. Also in ancient prophecies from the mayans, and hopis, they speak of the world being destroyed 3 or 4 times. The last one was by water and this next destruction will be fire.
Submitted by Visitor on 27 March 2008 - 10:46am.

http://www.cosmosmagazine.com/node/1810

i wondering if modern man is a lot older than what the bible says(6000 yrs)...you draw you own conclusions:

Who knows, but I do believe I have heard that some Biblical scholars have felt that the actual time frame for mankind is at about 10,000 years. No matter how hard we try to find out though, our own methods to determine actual time is going to fall short of the truth, so we are left with our faith alone to prove what we believed in, in the first place.

As for the future and the climate. I personally believe that we are oging to go through a cool down, which might impede crops from some of the most fertile lands we currently farm on.