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Record amounts of polar ice around Antarctica
09-24-2012, 08:26 PM,
#1
Record amounts of polar ice around Antarctica
Original URL: http://www.theregister.co.uk/2012/09/21/arctic_antarctic_sea_ice_record/
Polar sea ice could set ANOTHER record this year

Exceptionally large amounts of it down south right now

By Lewis Page

Posted in Science, 21st September 2012 09:14 GMT

The world's media is extremely excited at the thirty-year record low extent of sea ice at the North Pole which occurred just days ago: but almost nobody is reporting on the fact that something almost equally unusual is going on down around the coasts of Antarctica.
[Image: antarctic_ice_nsidc.jpg]
Whoa, that's a lot of ice

Even as the Arctic sea ice starts to grow again from its summery shrunken condition, the austral ice at the planet's other pole may have yet to reach its wintery peak extent. As the graph shows, at the moment it is much larger than normal for the time of year, and depending on what happens in the next week or so it might hit a record high. There has already been a point at which a record for that date occurred, and only a handful of higher daily satellite readings have ever been taken.

The sea ice around the coasts of Antarctica on average covers roughly the same amount of sea as the north-polar sea ice does: it's just as important, though you wouldn't know it by looking at the world's press right now. Another thing not everyone knows is that even as Arctic ice has been on a long decline since satellite measurements began, the Antarctic ice has been growing steadily (this despite well-publicised ice shelf losses around the Western Antarctic peninsula, bucking the overall continental trend).

Taking all the world's sea ice together, then - as opposed to focusing exclusively on the Arctic - the picture is far less gloomy than most media outlets would have you believe. Generally the world has between 15 and 23 million square km of the stuff: at the moment it has a bit more than 18m, which is approximately 1.5m below average for this time of year. Earlier this year, though, it was nearly 1m up on the seasonal average.

There are some other things to bear in mind, too: melting sea ice, of course, doesn't mean rising sea levels the way melting glaciers or ice sheets on land might. Then there's the fact that the satellite record is so short and the polar regions so little known: longer term variations like the one we're seeing may be entirely normal. Famously the president of the Royal Society (Blighty's premier scientific institution) wrote to the Admiralty in 1817:

It will without doubt have come to your Lordship's knowledge that a considerable change of climate, inexplicable at present to us, must have taken place in the Circumpolar Regions, by which the severity of the cold that has for centuries past enclosed the seas in the high northern latitudes in an impenetrable barrier of ice has been during the last two years, greatly abated.

(This) affords ample proof that new sources of warmth have been opened and give us leave to hope that the Arctic Seas may at this time be more accessible than they have been for centuries past ...

Even so, though, many are warning of an "ice free" arctic - perhaps in only a few years from now. Then, of course, without ice to reflect heat back into space, runaway global warming would surely be a certainty?

One should note first of all that "ice free" in a satellite observation sense doesn't mean "free of ice" - there would still be a lot of ice floating about in that scenario. Then, however, it's also worth considering what Steffen Tietsche, a polar ice expert at the Max Planck Institute for Meteorology in Hamburg, has to say. Tietsche and his colleagues wrote last year [1] in a leading peer-reviewed geophysics journal:

We examine the recovery of Arctic sea ice from prescribed ice-free summer conditions in simulations of 21st century climate in an atmosphere–ocean general circulation model. We find that ice extent recovers typically within two years.

The excess oceanic heat that had built up during the ice-free summer is rapidly returned to the atmosphere during the following autumn and winter, and then leaves the Arctic partly through increased longwave emission at the top of the atmosphere and partly through reduced atmospheric heat advection from lower latitudes. Oceanic heat transport does not contribute significantly to the loss of the excess heat.

Our results suggest that anomalous loss of Arctic sea ice during a single summer is reversible, as the ice–albedo feedback is alleviated by large-scale recovery mechanisms. Hence, hysteretic threshold behavior (or a “tipping point”) is unlikely to occur during the decline of Arctic summer sea-ice cover in the 21st century.

So, all in all, probably not time to panic yet.
Links

http://www.theregister.co.uk/2011/02/10/no_tipping_point_for_arctic_sea_ice/
[Image: conspiracy_theory.jpg]
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09-25-2012, 01:19 AM, (This post was last modified: 09-25-2012, 10:11 PM by rsol.)
#2
RE: Record amounts of polar ice around Antarctica
This is surface measurements, as in 15% ice to sea. That's about ice breaking off and floating around as sea ice. Its important to note that you could have no Antarctic at all and still have a greater % of sea ice. As long as its over 15% that graph would look crazy huge even if the Antarctic was eviscerated with just bits of ice floating on the surface. What im saying is this is a rather blunt tool for proving a point.

I would point out that climate models predicted this. I can say that greater snow fall is predicted for the next 50 or so years. This is supposed to offset the melt but not in all certainty. I believe this to be due to greater precipitation and wind speeds over the poles. They have not included precipitation in this "study". But then, this is a piece by the register, not a climate study.

What this piece has done is take about 3 lines from a graph and then basically said "see?". Interesting to note the erratic nature of the graphs in both the 2011 and 2012 lines. This shows big differences year to year. That is not a good sign of a stable climate. If they had at least some correlation i wouldn't be so apprehensive. the 2011 line is everywhere.

shall we have a look at the Arctic picture?
[Image: extent_graph_2011.png]

how about a proper relationary image?
[Image: arc_antarc_1979_2011.png]

Please note the strong lines are the overall trends with the thin lines showing anomalous readings. what we must also note is that the inclination of Arctic sea ice lessening is not on average being propped up by the Antarctic. yes, there is an increase these past few months but not enough to offset the trend. Anomalous readings will prop you up but that's like using a wet day as an indicator for it always raining.

Check the overall trend lines. note the angle. I would be happier if that blue line wasn't so steep.I do not think there is a correlation between more loss on the Arctic and greater increase in the Antarctic. Its not like snow migrates from north to south. It's a simple winter/summer cycle. even if the Antarctic sea ice doubled, with the Arctic gone, that is not going to make for equilibrium. If anything it would only make things worse. shifts in weather patterns are the real issue with climate change.

For all case and purposes you can see that there is a relationship well studied and understood by climatologists. this is not a wild card.

re-edit..... supposition removed to clarifySmile
note to self, dont drink/smoke and type. do drugs kids, just dont type afterwards, just get some chips.
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09-25-2012, 06:33 PM,
#3
RE: Record amounts of polar ice around Antarctica
Arctic ice loss was hyped
http://bishophill.squarespace.com/
Sep 24, 2012

There's a terrible sense of deja vu about this story (via Climate Depot):

In a September 18 video posted by NASA on its website, they admit that the Arctic cyclone, which began on August 5, “wreaked havoc on the Arctic sea ice cover" by "breaking up sea ice."

This is exactly what happened in 2007, when weeks of hype was followed by a quiet admission that the root cause of the loss of ice was winds and ocean currents. I had put the possibility that the 2012 ice loss was similarly down to factors other than global warming to Mark Brandon, a polar regions scientist. He agreed that this was very much a possibility and decried the poor coverage of the issue in the media. There can certainly be little doubt that we have only heard part of the story.

It would be interesting to see who hyped the ice loss in 2007 and who corrected their stories when the truth came out. And it would be interesting to see who hyped it again this time.
An error does not become truth by reason of multiplied propagation, nor does truth become error because nobody sees it.
Mohandas Gandhi


Each of us is put here in this time and this place to personally decide the future of humankind.
Did you think you were put here for something less?
Chief Arvol Looking Horse
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09-25-2012, 09:40 PM, (This post was last modified: 09-25-2012, 09:50 PM by h3rm35.)
#4
RE: Record amounts of polar ice around Antarctica
(09-25-2012, 01:19 AM)rsol Wrote: Check the overall trend lines. note the angle. I would be happier if that blue line wasn't so steep. I would suggest the reasoning for this is the land mass at the Arctic. Thus makes it more erratic. It also shows that the Arctic is a better indicator for change than the Antarctic as the effects from climate change are not so slight.
Your wording here confused me. Would it be possible to rephrase as "the [lack of or smaller] land mass at the arctic" and still accurately represent what you were saying?
[Image: conspiracy_theory.jpg]
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09-25-2012, 09:59 PM, (This post was last modified: 09-25-2012, 10:15 PM by rsol.)
#5
RE: Record amounts of polar ice around Antarctica
(09-25-2012, 09:40 PM)h3rm35 Wrote:
(09-25-2012, 01:19 AM)rsol Wrote: Check the overall trend lines. note the angle. I would be happier if that blue line wasn't so steep. I would suggest the reasoning for this is the land mass at the Arctic. Thus makes it more erratic. It also shows that the Arctic is a better indicator for change than the Antarctic as the effects from climate change are not so slight.
Your wording here confused me. Would it be possible to rephrase as "the [lack of or smaller] land mass at the arctic" and still accurately represent what you were saying?

Im just thinking to myself. am i stoned here? have i suddenly swapped land masses here?sorry. killed to avoid confusionWink ta herm. thought that was nailed down. arctic, antarctic. so close yet so farSmile
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09-25-2012, 11:38 PM, (This post was last modified: 09-25-2012, 11:40 PM by h3rm35.)
#6
RE: Record amounts of polar ice around Antarctica
hey no problem here if you adjust your midframe before typing and things get a little muddled... I do it all the time! Hopefully people here will check and make sure that both they and I know what I'm talking about when I'm less than clear.

I probably wouldn't have paid much attention six months out of the year, but my brother's down at McMurdo right now.
[Image: conspiracy_theory.jpg]
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