Radar readings: Image shows a British Antarctic Survey aircraft conducting the survey.
Credit: Carl Robinson/British Antarctic Survey.
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.
HEAR!! HEAR!!
Well I couldn't have said it better myself, BOLLOCKS!!! just about cover's the whole subject, well done mate
Bollocks Revenge
http://www.dailytech.com/Temperature+Monitors+Report+Worldwide+Global+Cooling/article10866.htm
Twelve-month long drop in world temperatures wipes out a century of warming
Over the past year, anecdotal evidence for a cooling planet has exploded. China has its coldest winter in 100 years. Baghdad sees its first snow in all recorded history. North America has the most snowcover in 50 years, with places like Wisconsin the highest since record-keeping began. Record levels of Antarctic sea ice, record cold in Minnesota, Texas, Florida, Mexico, Australia, Iran, Greece, South Africa, Greenland, Argentina, Chile -- the list goes on and on.
No more than anecdotal evidence, to be sure. But now, that evidence has been supplanted by hard scientific fact. All four major global temperature tracking outlets (Hadley, NASA's GISS, UAH, RSS) have released updated data. All show that over the past year, global temperatures have dropped precipitously.
A compiled list of all the sources can be seen here. The total amount of cooling ranges from 0.65C up to 0.75C -- a value large enough to wipe out most of the warming recorded over the past 100 years. All in one year's time. For all four sources, it's the single fastest temperature change ever recorded, either up or down.
Scientists quoted in a past DailyTech article link the cooling to reduced solar activity which they claim is a much larger driver of climate change than man-made greenhouse gases. The dramatic cooling seen in just 12 months time seems to bear that out. While the data doesn't itself disprove that carbon dioxide is acting to warm the planet, it does demonstrate clearly that more powerful factors are now cooling it.
Let's hope those factors stop fast. Cold is more damaging than heat. The mean temperature of the planet is about 54 degrees. Humans -- and most of the crops and animals we depend on -- prefer a temperature closer to 70.
Historically, the warm periods such as the Medieval Climate Optimum were beneficial for civilization. Corresponding cooling events such as the Little Ice Age, though, were uniformly bad news.
So all this is verifiable fact, AND YET everytime I turn to the tube or a MSM newspaper, or my Govt!! some &^^%$*@ talking head is trying to convince me of the exact opposite? AND YOU WONDER WHY I AM ANGRY YOU DOLT!!
why are right wingers so angry all the time
what are the facts
co2 is a greenhouse gas accounting for some 10 or more % of the 30C greenhouse warming that keeps our planet from being an ice cube ... that translates to about 3c or 4C of the warming ... it stands to reason that an increase in co2 should have some effect on climate ... the 25% increase in co2 over the last 50 or so years would mean an increase of a degree or so ... i believe that this is what has actually been measured
another fact is that we have developed a lot of climate computer models ... the models indicate some global temperature increase based on current co2 production levels ... the results from some models in replicating the world's temperature over the last 1000 years look awfully good but i don't think that they are good enough to be totally convincing ... the "system" - the earth-sun system is way too complex ... but the efforts are worthwhile because they are at least indicative and will get better with time
the "precautionary principle" states that we should err on the side of caution ... the possible outcomes of atmospheric co2 increases range from nothing to possible catastrophic changes due to tipping points/triggers being breached such as large scale methane releases ... the geologic record indicates that such events have happened ... do you really want us to to do this uncontrolled experiment?
then, what is the cost of reducing and eventually eliminating our reliance on fossil fuels? ... cleaner air? ... getting rid of our dependence of the middle east in 20 years? ... achieving energy sustainability, say in 100 years? ... mitigating the effect of a disappearing resource (oil) over the next 50 years? ... creating new business opportunities right away? ... never mind slowing down the rate of climate change
this last point means that whatever you think, or i think ... that the course is set ... we will see climate change ... the best we can do is to slow it down and prevent a run-away collapse ... that is why a global program is the right thing to do although fraught with difficulty
i'm 66 and don't expect this to effect me much ... and i live in canada so a warmer winter is ok ... but i have kids and grandkids so i do care
a final word ... the only short term solution to a massive switch in energy from fossil fuels is nuclear ... unfortunately ... longer term we could and should, as a planet, switch to solar based energy (biomass, pv, solar concentrators, wind, waves & tides, geothermal, etc.) ... and we need to be more conservative and efficient in our use of energy
and i don't want to hear anymore about hydrogen ... it's not an energy source ... free hydrogen doesn't exist on our planet, or at least not for long ... it's just one of many energy storage and transport mechanisms and will possibly be useful in some way or another, or not
old news
A volcano under the ice was discussed in 91 in a talk at McMurdo Station. They found three of them that were the cause of ice streams feeding into the Ross Ice Shelf.
ice
The global warming morons will continue to advance the fraud as long as there are morons who will believe it. They are fear mongers who seek financial gain. It`s all about money and influence.
Earth Core
A more active and warming Earth's core would explain the increase in worldwide volcanic acivity, tundra frost melts,earthquake activity and now Antarctic breakaway icesheets. Lets have an open discussion about this and other theories without the heavy handedness from monied interests!!
ocean level
One factor I have not seen mentioned by people discussing ocean levels is the quantities of matter washed into the seas constantly. This seems as if it would add up over time.
see the dead zones in the Pacific
http://www.climateark.org/blog/2006/08/oregons_ocean_dead_zone.asp
this one is far from Oregon,
http://www.mindfully.org/Plastic/Ocean/Moore-Trashed-PacificNov03.htm
Global Warming
How can any intelligent person argue against decreasing our burning of fossil fuels, especially scientists? This is clearly a separate issue that does not involve global warming but does involve wars, pollution and economics. Think about that.
More Skeptics as Evidence Mounts against Global Warming
I covered this article when it first hit the news wires back in January. Antarctica is the global warming crowd's Achilles Heel - ice is growing on three sides of the continent and satellite images show more ice in just the last 20 years. Unfortunately for skeptics, little media attention is given to those scientific bits that contradict the popular view of global warming.
Click here to learn more about Global Warming.