![Antarctic_Melt-0acf6[1]](http://wattsupwiththat.files.wordpress.com/2014/05/antarctic_melt-0acf61.jpg?quality=83)
Guest post by David Middleton
A Geological Perspective on the “Irreversible Collapse” of the West Antarctic Ice Sheet
It’s “old” news, as this publication from 1999 shows us.
“Map showing dated locations used to resolve Holocene grounding-line retreat to its present position in the Ross Sea Embayment. Although the detailed structure of past grounding-line positions is unknown, dotted lines show the simplest grounding-line pattern consistent with the dates in the text.”
(Conway et al., 1999)
The history of deglaciation of the West Antarctic Ice Sheet (WAIS) gives clues about its future. Southward grounding-line migration was dated past three locations in the Ross Sea Embayment. Results indicate that most recession occurred during the middle to late Holocene in the absence of substantial sea level or climate forcing. Current grounding-line retreat may reflect ongoing ice recession that has been under way since the early Holocene. If so, the WAIS could continue to retreat even in the absence of further external forcing…
The collapse (retreat of the grounding line) began about 20,000 years ago. It is irreversible because “the WAIS could continue to retreat even in the absence of further external forcing” and there are no topographic obstacles to prevent it from flowing downhill into the ocean.
One has to wonder why this paper didn’t merit panic-stricken headlines in 1999
It’s the same story, just from the other side of the peninsula.
Reference
H. Conway et al, 1999. Past and Future Grounding-Line Retreat of the West Antarctic Ice Sheet. Science 8 October 1999: Vol. 286 no. 5438 pp. 280-283
DOI: 10.1126/science.286.5438.280
http://www.sciencemag.org/content/286/5438/280.abstract
Abstract
The history of deglaciation of the West Antarctic Ice Sheet (WAIS) gives clues about its future. Southward grounding-line migration was dated past three locations in the Ross Sea Embayment. Results indicate that most recession occurred during the middle to late Holocene in the absence of substantial sea level or climate forcing. Current grounding-line retreat may reflect ongoing ice recession that has been under way since the early Holocene. If so, the WAIS could continue to retreat even in the absence of further external forcing.
(Full text available with registration.)
Yup. Now where in the NASA PR that started this media frenzy is there any mention of the sub glacial newly discovered Hudson volcano. That was, of course, a rhetorical question.
Regards
Rud Istvan says:
May 17, 2014 at 2:04 pm
Meant Mountains. First wrote Range.
No wonder the PIG is always the poster child for supposed Antarctic ice mass melting. Its behavior can’t possibly be caused by anything other than CO2.
When I search for actual summer temperature readings from the PIG, all I find are modeled anomalies rather than real data.
Ice core record shows Antarctic cooling, 1882-2006:
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00496.1
The abstract states that, “This cooling trend is in contrast to a surface temperature record from Ross Island (Scott Base) where significant spring warming is observed”. Yet the average high T for warmest months (Dec & Jan) at Scott Base is still below freezing.
Gottcha !
Ha ha !
http://digitalcommons.library.umaine.edu/cgi/viewcontent.cgi?article=1155&context=ers_facpub&sei-redir=1&referer=http%3A%2F%2Fscholar.google.com%2Fscholar_url%3Fhl%3Den%26q%3Dhttp%3A%2F%2Fdigitalcommons.library.umaine.edu%2Fcgi%2Fviewcontent.cgi%253Farticle%253D1155%2526context%253Ders_facpub%26sa%3DX%26scisig%3DAAGBfm3eZn37oGIdPwIqnaLtBqKZxHcX9Q%26oi%3Dscholarr#search=%22http%3A%2F%2Fdigitalcommons.library.umaine.edu%2Fcgi%2Fviewcontent.cgi%3Farticle%3D1155%26context%3Ders_facpub%22
And I did not even have to use the “Way Back Machine” to find this !
The “collapse” is just one of a plethora of hypotheses ! AKA, an idea. Plain and simple; except for the Eric Rignot’s trolling our current world for booty to fuel his cocaine wishes and heroin dreams.
Ha ha
FU
The “funny thing” about ice sheets is that they are always either collapsing or expanding. The WAIS was cyclically “collapsing” as far back as the Middle Miocene…
http://www.sciencedirect.com/science/article/pii/S0012821X03005090
All, I am given to understand that Judith will publish the abridged version at CE tomorrow. Enjoy the images from the papers themselves, and from contemporary others.
http://www.theguardian.com/commentisfree/2014/may/17/climate-change-antarctica-glaciers-melting-global-warming-nasa
Eric Rignot is telling his version of the collapse in the Guardian too.
@Keith.,
Ringnut did get one thing right,
It was likely to retreat anyway. We might have sped up the process… or we might not have. Either way, we won’t know for 200 to more than 1,000 years. Even then, we won’t know if it would have done what it did anyway.
Otherwise, it is an imminent catastrophe, worthy of bankrupting the United States in a futile effort to do something about it.
/Sarc
Joe Public
“Just 4 days later, the Beeb also reported the ‘good’ news that “Global warming can make sea level plunge”
In the worst circumstances, the “hole” left behind could result in a sea level drop of 25 metres but Dr Bratton (Dr John Bratton of the US Geological Survey) told BBC News Online that his conservative estimates suggest a drop of up to 1.5m.” [My bold]
http://news.bbc.co.uk/1/hi/sci/tech/467928.stm”
That is a wonderful article but did you notice who wrote it?
Damian Carrington, Head of Environment at the Guardian.
New one today…
http://www.bbc.co.uk/news/science-environment-27465050