-- R.G. Menzies
LIBERTARIAN/CONSERVATIVE DIGEST AND COMMENTARY FROM AN ACADEMIC PSYCHOLOGIST in Brisbane, Australia. My academic publications are widely read
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That good ol' Antarctic peninsula again
These guys below are remarkably incurious. They see the sudden change in parts of the Antarctic peninsula but are sure they have a magic decoder ring that tells then what causes the change -- global warming, of course. But how come the change is so sudden and so recent? And how come it has happened during a period when there has been NO global warming? Their explanations linking it to global warming are obviously just desperate stabs in the dark
And the real cause is known anyhow. There have been several recent reports of subsurface vulcanism in the Western margin and the peninsula. Having a volcano underneath an ice mass is a pretty good way of melting some ice. And volcanoes are sudden and episodic. So vulcanism explains what the Warmists could not -- the SUDDEN onset of the melting. And the second aspect of volcanoes -- that they are episodic -- shows how absurd are the great extrapolations offered below. Volcanoes are mostly caused by tectonic shifts so most erupt and then stop as the plates re-adjust. You cannot reasonably project vulcanism into the future, let alone the distant future. It could stop tomorrow. So the alarming predictions below are just the usual sort of baseless scare that we expect from Greenies
The article below is from the Daily Mail and they obviously didn't like the Warmist claims either. They followed the original story with a quote from a polar expert which pointed out a hole in the story and added a "box" to the article (the words from the capital letters onward) which also shows the absurdity of saying that the Antarctic is being affected by global warming
The Antarctic ice sheet in a previously stable part of the frozen continent is thinning at a rate that has added more than 300 trillion litres of water to the surrounding ocean in the past six years.
Scientists have expressed alarm at the rate of ice loss at the Southern Antarctic Peninsula, which had shown no signs of change until 2009, when it started suffering rapid destabilisation.
Now new research has revealed that glaciers along the peninsula have been melting at accelerating rates, causing the mass of ice there to reduce.
The loss of ice in the region is so large that it has caused the gravitation field of the Earth to change, according to some measurements conducted by scientists.
Since 2009, scientists estimate that the volume of water lost from the ice sheet is equivalent to a body of water larger than Lake Winnipeg in Manitoba, Canada or 350,000 Empire State Buildings.
Researchers warn that the melting glaciers are likely to drive rising sea levels if they continue to melt.
They blame the flow of warm subsurface water from the deep ocean for causing the melting of the ice sheets to accelerate.
The Amundsen Sea has long been thought to be the weakest ice sheet in the West Antarctic.
A study published in December suggests the barren region is haemorrhaging ice at a rate triple that of a decade ago.
Researchers believe that the melting of glaciers in West Antarctica, which contain enough water to raise sea levels by at least a metre, may be irreversible.
The findings of the 21-year study by Nasa and the University of California, Irvine claim to provide the most accurate estimates yet of just how fast glaciers are melting in the Amundsen Sea Embayment.
Scientists found the rate by taking radar, laser and satellite measurements of the glaciers' mass between 1992 and 2013.
They found they lost an average 83 gigatons per year (91.5 billion US tons), or the equivalent of losing the water weight of Mount Everest every two years.
Dr Bert Wouters, an earth observation scientist at the University of Bristol who lead the study, said: 'The fact that so many glaciers in such a large region suddenly started to lose ice came as a surprise to us.
'It shows a very fast response of the ice sheet: in just a few years the dynamic regime completely shifted.
'To date, the glaciers added roughly 300 cubic km of water to the ocean. That's the equivalent of the volume of nearly 350,000 Empire State Buildings combined.'
Ice sheets in Antarctica have until recently showed significant resilience to the impacts of global warming. Additional snowfall on the continent has meant some glaciers have actually grown in size.
On the Southern Antarctic Peninsula, the glaciers there appeared to be relatively stable – the flow of ice into the ocean occurred at the same rate as new ice was added at the top of the glaciers.
However, in 2009, several glaciers along the coastline – which measures 466 miles (750km) – started to lose ice at 14 cubic miles (60 cubic km) a year.
Dr Wouters and his colleagues, whose work is published in the journal Science, used radar measurements made by the European Space Agency's CryoSat-2 satellite to measure the thickness of the ice over the region.
Using five years of data they found the ice surface appears to be falling by around 13 feet (four meters) each year.
Another satellite mission – the Gravity Recovery and Climate Experiment – also revealed a slight change in the gravity field of the Earth as a result of the dwindling ice.
Dr Wouters said that it appears a change in the winds that encircle Antarcica in response to global warming, was pushing warmer waters from the Southern Ocean towards the ice sheet.
Here they eat away at the ice shelves and glaciers that float on the surface of the ocean from below.
Dr Wouters said: 'It appears that sometime around 2009, the ice shelf thinning and the subsurface melting of the glaciers passed a critical threshold which triggered the sudden ice loss.
'However, compared to other regions in Antarctica, the Southern Peninsula is rather understudied, exactly because it did not show any changes in the past, ironically.
'To pinpoint the cause of the changes, more data need to be collected.
'A detailed knowledge of the geometry of the local ice shelves, the ocean floor topography, ice sheet thickness and glacier flow speeds are crucial to tell how much longer the thinning will continue.'
However, Professor Andy Shepherd, director of the Centre for Polar Observation and Modelling at the University of Leeds, said he felt the ice loss may actually be smaller than the study estimated.
Professor Shepherd, who is also the principal scientific advisor to the European Space Agency's Cryosat mission, said: 'I think the new estimates of ice loss computed from them are far too high, because the glaciers in this sector just haven't speeded up that much.
'It could be that a bigger chunk of the thinning is down to snowfall fluctuations than the authors have accounted for, and so I would be cautious about the new numbers until more information is to hand.'
... BUT ELSEWHERE THE SEA ICE SEEMS TO BE GROWING
Growing sea ice surrounding Antarctica could prompt scientists to consider relocating research stations on the continent, according to the operations manager of the Australian Antarctic Division.
Rob Wooding said that resupplying Australia's Mawson Station - the longest continuously operated outpost in Antarctica - relied on access to a bay, a task increasingly complicated by sea ice blocking the way.
He said that at Mawson, the ice typically breaks up for one or two months of the summer, but in the last four to six years this has not happened every year and some years only partially.
He said: 'We are noticing that the sea ice situation is becoming more difficult.
'In the 2013-4 season we couldn't get anywhere near Mawson due to the sea ice and we had to get fuel in there by helicopter which is inadequate for the long-term sustainability of the station.'
He said that French and Japanese bases on the continent have had similar problems.
Tony Worby, from an Australian centre studying Antarctic climate and ecosystems, said that in contrast to the Arctic where global warming is causing ice to melt and glaciers to shrink, sea ice around Antarctica was increasing.
It hit a new record in September last year, with the US-based National Snow and Ice Data Center reporting that the ice averaged 20.0 million square kilometres (7.72 million square miles) during the month.
Scientists have struggled to predict sea ice conditions, which are believed to be affected by the strong winds of the Southern Ocean which can push the ice out from the continent of Antarctica.
This does not happen in the Arctic because the ocean is hemmed in by land masses.
By JR on Saturday, May 23, 2015
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