Antarctic Ice Discussion

[stewfox]

You're possibly right re. media bias etc, and right that if it's needed it'd be better in a new thread. However, there is clear and obvious 'bias' between the importance/significance of what's happening in the Arctic (major significant long term dramatic changes to the whole dynamic of the region), and the Antarctic (slight variation around a generally static long term mean). So in some ways it's hardly surprising the Arctic news is getting more coverage than the Antarctic. It's like two car accidents, one a major pile-up involving much destruction, and the other a minor prang which caused a small dent - and we know which of these two would make headline news.

But we know had the Antarctica got a record low 7% below average it would be headline news in all the media thats the point !

The Sun 'get you bucket and spade ready for trips to Antarctica'

The Daily Mail Coldest winter in 1000 yrs on the way Antarctica melts out

BBC ' Ice shelf to collapse in 30 yrs' Maldives under threat from melting Antarctica ice , RECORD low levels etc etc

I am not suggesting the reasons for small increases could be a result of global warming , I find it interesting thats all.

Edited September 26, 2012 by stewfox

[BornFromTheVoid]

But we know had the Antarctica got a record low 7% below average it would be headline news in all the media thats the point !

The Sun 'get you bucket and spade ready for trips to Antarctica'

The Daily Mail Coldest winter in 1000 yrs on the way Antarctica melts out

BBC ' Ice shelf to collapse in 30 yrs' Maldives under threat from melting Antarctica ice , RECORD low levels etc etc

I am not suggesting the reasons for small increase could be a result of global warming , I find it interesting thats all.

I don't think it Antarctic lows would have made the news. The same way the daily record lows in the Arctic last February didn't make the news.

[stewfox]

I don't think it Antarctic lows would have made the news. The same way the daily record lows in the Arctic last February didn't make the news.

I think there were 300 news summaries in Feb 2012 re less ice , most referred to record lows including feb 2012 but the point is not worth debating me thinks anymore.

http://www.bbc.co.uk/news/science-environment-17143269

http://www.worldweatherpost.com/2012/02/15/unusual-weather-pattern-freezes-europe-shifts-arctic-ice

http://nsidc.org/arcticseaicenews/2012/02/arctic-ice-extent-low-overall-high-in-the-bering-sea/

http://www.sciencedaily.com/releases/2012/02/120227111052.htm

http://www.bbc.co.uk/news/science-environment-17143269

http://content.usatoday.com/communities/sciencefair/post/2012/02/arctic-sea-ice-winter-snow-usa-blizzard-climate-change/1

[BornFromTheVoid]

I think there were 300 news summaries in Feb 2012 re less ice , most referred to record lows including feb 2012 but the point is not worth debating me thinks anymore.

http://www.bbc.co.uk...onment-17143269

http://www.worldweat...ifts-arctic-ice

http://nsidc.org/arcticseaicenews/2012/02/arctic-ice-extent-low-overall-high-in-the-bering-sea/

http://www.scienceda...20227111052.htm

http://www.bbc.co.uk...onment-17143269

http://content.usato...limate-change/1

I saw no mention of the daily record lows in February on any of the news sites there... anywho... Antarctic sea ice doing well for itself at the moment, at least nobody can deny that

[PeteG]

But we know had the Antarctica got a record low 7% below average it would be headline news in all the media thats the point !

The Sun 'get you bucket and spade ready for trips to Antarctica'

The Daily Mail Coldest winter in 1000 yrs on the way Antarctica melts out

BBC ' Ice shelf to collapse in 30 yrs' Maldives under threat from melting Antarctica ice , RECORD low levels etc etc

I am not suggesting the reasons for small increases could be a result of global warming , I find it interesting thats all.

Its seasonal ice and its floating on the sea so whether it is more or less extensive makes no difference to sea level. By next April or May most of it will all have melted and then by this time next year it'll be back again somewhere near the same area + or - a bit.

It won't make the headlines here because (a) its a long way away and not in our backyard and (http://forum.nwstatic.co.uk//public/style_emoticons/<#EMO_DIR#>/cool.png being seasonal a small annual variation is of little importance.

If the increase led to the ice approaching the southern tip of S America I'm sure it would make the headlines.

[stewfox]

Its seasonal ice and its floating on the sea so whether it is more or less extensive makes no difference to sea level. By next April or May most of it will all have melted and then by this time next year it'll be back again somewhere near the same area + or - a bit.

It won't make the headlines here because (a) its a long way away and not in our backyard and ( being seasonal a small annual variation is of little importance.

If the increase led to the ice approaching the southern tip of S America I'm sure it would make the headlines.

Obvioulsy sea levels dont change re sea ice freeze or melt, if people don't believe record lows wouldn't be reported so be it. Mutiverse universes are not in general use to 2080 so I cant prove what would be reported.

http://news.bbc.co.uk/1/hi/8311838.stm

The record cold in South America this year didnt make many headlines

http://blog.heartlan...in-perspective/

Edited September 26, 2012 by stewfox

[BornFromTheVoid]

Obvioulsy sea levels dont change re sea ice freeze or melt, if people don't believe record lows wouldn't be reported so be it. Mutiverse universes are not in general use to 2080 so I cant prove what would be reported.

http://news.bbc.co.uk/1/hi/8311838.stm

The record cold in South America this year didnt make many headlines

http://blog.heartlan...in-perspective/

I can't see evidence for record breaking cold in South America, only a cold spell. Certainly wasn't as prolonged as the US heatwave.

But climate related or not, issues in the US, Europe, Australia and such always generate more headlines than elsewhere.

[BornFromTheVoid]

A new daily record high in Antarctic, and just 30k of a new record high for the satellite period.

http://arctic.atmos.uiuc.edu/cryosphere/antarctic.sea.ice.interactive.html

[knocker]

Variable glacier response to atmospheric warming, northern Antarctic Peninsula, 1988–2009

http://www.the-cryosphere.net/6/1031/2012/tc-6-1031-2012.pdf

[stewfox]

A new daily record high in Antarctic, and just 30k of a new record high for the satellite period.

http://arctic.atmos....nteractive.html

How much longer before the ice hits the shores of South America ?

[BornFromTheVoid]

How much longer before the ice hits the shores of South America ?

You can try estimate from the animation http://arctic.atmos.uiuc.edu/CT/animate.antarctic.color.0.html

Based on current trends and disregarding seasons, I'd give it a year

[stewfox]

Interesting

http://www.prisonplanet.com/antarctic-ice-area-sets-record-high.html

Are global sea ice levels similar to 30 years ago ??

--------------------------------------

The Antarctic dimensions come partly at the expense of Arctic sea ice†said Mr Brill. “Over the 33-year period aggregate global sea ice volumes have remained steady, but there are fluctuations between the two polar areas from year to year. The fluctuations are the result of ocean currents and wind patterns, rather than temperaturesâ€.

“Antarctic ice is much more important than that of the Arctic. The area of its sea ice is a million square kilometres larger than the highest value ever recorded in the Arctic. Then, of course, the Antarctic is an entire continent, with more than 90% of the earth’s glacial ice†said Mr Brill.

------------------------------------

[BornFromTheVoid]

Interesting

http://www.prisonpla...ecord-high.html

Are global sea ice levels similar to 30 years ago ??

--------------------------------------

The Antarctic dimensions come partly at the expense of Arctic sea ice†said Mr Brill. “Over the 33-year period aggregate global sea ice volumes have remained steady, but there are fluctuations between the two polar areas from year to year. The fluctuations are the result of ocean currents and wind patterns, rather than temperaturesâ€.

“Antarctic ice is much more important than that of the Arctic. The area of its sea ice is a million square kilometres larger than the highest value ever recorded in the Arctic. Then, of course, the Antarctic is an entire continent, with more than 90% of the earth’s glacial ice†said Mr Brill.

------------------------------------

First you quote a heartland blog then prison planet?

I'm afraid it's disinformation again, and mixing up sea and land ice.

Clearly the Arctic ice has been declining at a much faster rate than the Antarctic has been gaining it.

Antarctic Decadal Average and last 6 years

Just the Antarctic decadal averages

Arctic Decadal Averages and last 6 years

[Devonian]

How much longer before the ice hits the shores of South America ?

2 days.

[stewfox]

First you quote a heartland blog then prison planet?

I'm afraid it's disinformation again, and mixing up sea and land ice.

Clearly the Arctic ice has been declining at a much faster rate than the Antarctic has been gaining it.

I can hardly quote from the BBC they dont mention the current state of the antarctic Global sea ice doesn't show a strong downward trend certainly not 1SD or 2 SD but we can seen a small downward shift in recent years.

[BornFromTheVoid]

I can hardly quote from the BBC they dont mention the current state of the antarctic Global sea ice doesn't show a strong downward trend certainly not 1SD or 2 SD but we can seen a small downward shift in recent years.

Here's another source for ya, Antarctic extent from the University of Bremen

And another

[Gray-Wolf]

I hope everyone is now satisfied that the seasonal ice extent from the southern hemisphere max is as significant as the northern hemisphere, outside of the basin, max extent?

Apart from either general silliness or a poor attempt to deflect attention from the northern hemisphere's disastrous melt season, I see no point in pursuing it further?

As with the northern hemisphere surely the interest should be focused on the melt season there?

This coming season we have the added interest of a possible major calve (taking it further up valley than ever recorded) of the feed glacier in the Pine Island complex and data concerning the progress of the warm bottom waters toward the Ross embayment both of which ,in my opinion, are real issues unlike the seasonal coming and going of winter ice in the southern ocean?

[jethro]

I hope everyone is now satisfied that the seasonal ice extent from the southern hemisphere max is as significant as the northern hemisphere, outside of the basin, max extent?

Apart from either general silliness or a poor attempt to deflect attention from the northern hemisphere's disastrous melt season, I see no point in pursuing it further?

As with the northern hemisphere surely the interest should be focused on the melt season there?

This coming season we have the added interest of a possible major calve (taking it further up valley than ever recorded) of the feed glacier in the Pine Island complex and data concerning the progress of the warm bottom waters toward the Ross embayment both of which ,in my opinion, are real issues unlike the seasonal coming and going of winter ice in the southern ocean?

Why? And why should attention be focussed upon melting?

[BornFromTheVoid]

Whilst I disagree with focusing all the attention on the melt, it is, at the moment, the most telling aspect of Antarctic sea ice.

If the minimum area begins to show a significant and sustained increase, this will suggest the increased formation of multiyear ice, which would be a big change. For now, no matter how high the ice climbs in September, it always falls back down to around 2 million by March, because the ice is generally so thin and fragmented there.

The Antarctic maximum doesn't tell us a whole lot about the ice, just like the Arctic reaching average last March/April was no sign of things to come.

[Gray-Wolf]

I'm sure you only ask the question for the sake of the 'nubes' that this current flurry of activity will have attracted here so I will answer in a way inclusive of all?

Firstly let us explain the differences between north and south pole. In the north we have an ocean surrounded by land which has enabled , over time, a very unique ocean to develop (unlike any other on the planet).Over the millenia that the basin was ice covered the 'protection that ice gave to the waters below allowed for a very deep stratification of the ocean to arise. This 'stratification was accentuated by the vast rivers that flow into the basin allowing for a freshening of the upper surface of the ocean allowing cold fresh water to dominate it's upper horizons and warmer ,saltier waters to underly this special layer. The South Pole is inside a vast, mountainous continent dominated by Km deep ice sheets. The ocean surrounding this land mass (the 'southern ocean') is a typical ocean with average salinity and temp profiles. Due to the lack of land the belt surrounding the antarctic continent has developed both the circumpolar winds and circumpolar current.

Due to the nature of 'normal oceans' ice development is limited there. We see this in the north (Bering sea) and around the Antarctic land mass over their respective winters. Due to both location and ice thickness this ice disappears early in the melt seasons. The only area 'immune ' from this melt in the southern hemisphere is the Weddell sea which is sheltered from the circumpolars by the Antarctic peninsula.

As such this sea ice plays little or no part in the 'Albedo effect' of those poles and no impact on the land mass of Antarctica from the southern winter ice (how could it with the cold driven winds the pour off that continent?).

As with the ice in the north there is an impact on wildlife.

Antarctica holds most of the planets reserves of fresh water in it's vast ice sheets. should they melt out then global sea levels will rise by many tens of metres. Our experience from the loss of the ice shelfs around the peninsula tells us that once the shelf is removed the glaciers behind accelerate dumping ever more ice into the ocean and impacting global seas levels.

The Antarctic peninsula is warming faster than any other place on the planet (it protrudes beyond the impacts of the circumpolars). We are now seeing similar ocean warmth spreading down the coast of Antarctic inside the circumpolars due to the access deep ocean canyons has afforded them and are now seeing the impacts on the ice shelfs soutrh of the Peninsula (Wilkins/Pine Island/Thwaites) with the warm waters now well on their way to the Ross Embayment (a shelf the size of France which is grounded on the Ross Sea sea Bed and rises up to 200ft above the ocean surface). The Ross Embayment also holds back the Majority of the East Antarctic Ice Sheet's drain glaciers.

Paleo evidenced shows us that the last time the planets temps were as high as today, with CO2 levels to match, the Ross Embayment did not exist (nor the Weddell sea ice) and there was an open water channel between the Ross and Weddell seas.

As such ,though important to the rates of global sea level change, the inevitable loss of Thwaites and the Pine Island complex fade into insignificance with both the impacts and speed of impacts the changes now beginning at Ross promise.

The 'phoney war' that our CFC dalliance has brought us should not breed any feeling of 'peace in our time' . It may well prove a bigger bug bare than help once the temp rises that the Arctic meltdown provides (as we'll see over the coming years?) filter through on top of the general rise in global temps (this past 30yrs). in some ways a slow 'drip ,drip' forcing would be far more stable than a near instant blast of a number of years warming over a short period of time? As we have seen with the Peterman calve this year meltwater floods will dislodge weakened ice as well as any tidal influence so when the basal assault by southern ocean waters is augment by a rapid uptick in surface melt (we already see upland melt behind Ross throughout the noughties) then we should all hold concerns for the integrity of the remaining ice shelf around Antarctica.

As noted earlier the Ross Shelf is not a floating ice tongue and so relies on contact friction to hold back the weight of ice pressing against it. Undercutting by warm southern ocean waters (as we see in P.I.G. and Thwaites) at the shelf front may lead to partial collapse on it's own but any float-off to the rear of the shelf due to melt water pressures will instantly destabilise the ice mass leading to a rapid collapse (and associated uptick in global sea levels).

If ever there was an area to study ice melt in it is the shelfs surrounding the Southern continent over the next ten years after the sea ice has melted out for the summer (Jan/Feb).

Any how this is my take on why monitoring the ice melt around Antarctica is important (and why any focus on seasonal 'winter extent' is just silly) and I just hope that I am not as 'in the ballpark' in my predictions here as I have proved to be across the Arctic basin (watch out for those permafrosts!!)?

Edited September 28, 2012 by Gray-Wolf

[BornFromTheVoid]

Taken from the NSIDC site http://nsidc.org/arc.../faq/#antarctic

Is wintertime Antarctic sea ice increasing or decreasing?

Wintertime Antarctic sea ice is increasing at a small rate and with substantial natural year-to-year variability. Specifically, the months of May, June, July, September and October show trends of increasing sea ice extent that are just slightly above the mean year-to-year variability. In more technical terms, the trends are statistically significant at the 95% level, although small.

Climate model projections of Antarctic sea ice extent are in reasonable agreement with the observations to date. The dominant change in the climate pattern of Antarctica has been a gradual increase in the westerly circumpolar winds. Models suggest that both the loss of ozone (the ozone hole that occurs in September/October every year) and increases in greenhouse gases lead to an increase in this climate pattern.

When winds push on sea ice, they tend to move it in the direction they are blowing, but the Coriolis effect adds an apparent push to the left. In the unconfined system of Antarctic sea ice, this pushes the ice northward away from the continent. By spreading sea ice westward and a little northward (and since we measure extent with a 15% cut-off) the gradual trend towards faster mean winds means a gradual trend toward spreading of the ice cover.

Moreover, this trend towards stronger circumpolar winds appears to be causing the sea ice decline near the Antarctic Peninsula. In general the winds tend to dive slightly southward as they approach the Peninsula, an effect of the mountain ridges of the Andes and other circulation features in the Amundsen and Bellingshausen Sea. A stronger wind from the northwest brings warmer conditions and therefore less ice to the region. Lastly, the El Nino and La Nina cycle also appear to influence sea ice in the Pacific sector. El Nino patterns (a warm eastern tropical Pacific) are associated with warmer winds and less ice; the opposite is true for La Nina.

Even if wintertime Antarctic sea ice were to increase or decrease significantly in the future, it would not have a huge impact on the climate system. This is because during the Antarctic winter energy from the sun is at its weakest point; its ability or inability to reflect the sun’s energy back into space has little affect on regulating the planet’s temperature.

I'd imagine all the text may put some people off, but it is a good read and explains things quite well.

[BornFromTheVoid]

Sorry for spamming!

CT has updated and Antarctic sea ice area is now just 11k off the record set in 2007.

http://arctic.atmos.uiuc.edu/cryosphere/antarctic.sea.ice.interactive.html

[knocker]

Study suggests large methane reservoirs beneath Antarctic ice sheet

The Antarctic Ice Sheet could be an overlooked but important source of methane, a potent greenhouse gas, according to a report in the August 30 issue of Nature by an international team of scientists.

http://news.ucsc.edu/2012/08/antarctic-methane.html

[keithlucky]

Antarctic ice has increased in height since there last study in 2008 according to Cryo Sat http://www.google.co...7TBecdH5Ic7GRvQ

[BornFromTheVoid]

Close... but no cigar. Antarctic sea ice area has dropped by nearly 140k, so it looks doubtful that the 2007 record will be broken this year.

Last 5 days

Anomaly............ Area ............ Average....2007 Record

0.8978714.. 15.9813147.. 15.0834436.. 16.2323818

1.0512513.. 16.1204205.. 15.0691690.. 16.2323818

1.1447686.. 16.2041264.. 15.0593576.. 16.2323818

1.1654477.. 16.2217293.. 15.0562811.. 16.2323818

1.0325397.. 16.0858021.. 15.0532627.. 16.2323818