Antarctic Ice Discussion

[stewfox]

While I agree that this should be getting more attention, that WUWT link really is a steaming pile. I hope you can see through that nonsense!

 

I think the 'expanding towards the equator' although 'technically correct' is a bit alarmist but par for the course.

 

I would 'expect' to see 'all things being equal' for ice melt to start at lower latitudes rather then higher latitudes.

 

This point needs further investigation

 

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

 

There is so much warm, salty Atlantic and Pacific water lurking just 100 meters below Arctic Ocean’s surface, that it could melt the winter ice completely several times over. As climate scientists noted, ““There are arguments in support of an important role for oceanic heat in shaping the Arctic pack ice. They are often keyed to the presence of warm intermediate-depth (150–900 m) water of Atlantic origin

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

 

but that's for the other thead , we rarely discuss whats going on through 95% of the artic ocean profile

 

http://en.wikipedia.org/wiki/Arctic_Ocean

Edited October 20, 2013 by stewfox

[keithlucky]

Quite amazing new record set  in October in Antarctic for sea ice extent, Were melt season should be underway!http://t.co/WBgbqyCgEm

Edited October 22, 2013 by keithlucky

[stewfox]

Quite amazing new record set  in October in Antarctic for sea ice extent, Were melt season should be underway!http://t.co/WBgbqyCgEm

 

Approximately 61 per cent of all the fresh water on the Earth is held down there and it doesn't get a mentioned.

 

Imagine if we had record lows in the Artic how that would be plastered everywhere

 

Here is NASA announcement

 

http://wattsupwiththat.com/2013/10/22/nasa-announces-new-record-growth-of-antarctic-sea-ice-extent/

 

 

Interesting to see what min is reached net year

[BornFromTheVoid]

Approximately 61 per cent of all the fresh water on the Earth is held down there and it doesn't get a mentioned.

 

Imagine if we had record lows in the Artic how that would be plastered everywhere

 

Here is NASA announcement

 

http://wattsupwiththat.com/2013/10/22/nasa-announces-new-record-growth-of-antarctic-sea-ice-extent/

 

 

Interesting to see what min is reached net year

 

Are you commenting that the Antarctic ice sheet is melting and not getting a mention?

[knocker]

Are you commenting that the Antarctic ice sheet is melting and not getting a mention?

 

That's what I assumed from the same link..

 

Moreover, the mere extent of sea ice does not necessarily say something about the volume of the ice, because that also depends on the thickness of the frozen layer. And the vast majority of the Antarctic ice mass is located on the Antarctic continent – and there the ice has decreased in recent years as a whole, particularly in West Antarctica.

 

 

Plus of course in summer the sea ice decreases to an area of about 3 x 10⁶  km².

[stewfox]

Are you commenting that the Antarctic ice sheet is melting and not getting a mention?

 

I plead the 5th Amendment

[knocker]

Ambitious science mission sets off for Antarctica

 

A team of British scientists is making final preparations for an ambitious Antarctic science mission. They aim to discover what’s causing the recent rapid ice loss from Pine Island Glacier on the West Antarctic Ice Sheet and whether this loss will continue to increase or slow down. The research is important for understanding the likely impact on future sea-level rise.

 

Dr Andy Smith, British Antarctic Survey (BAS) is the Science Programme Manager for the NERC-funded iSTAR programme. Speaking this week at the British Science Festival in Newcastle he said:

 

“We used to think that the volume of water flowing from Antarctica’s melting glaciers and icebergs into the ocean was equal to the amount of water falling as snow onto the ice sheet; and that this process was keeping the whole system in balance. But Pine Island and Thwaites glaciers on the West Antarctic Ice Sheet (WAIS) are losing ice at a faster rate than they are being replenished. This affects sea level all over the world. The speed of changes to this region has taken scientists by surprise and we need to find out what’s going on.â€

 

http://www.antarctica.ac.uk/about_bas/news/news_story.php?id=2306

 

I like the touch with the seals.

Edited October 26, 2013 by knocker

[knocker]

Geosciences column: Playing back the Antarctic ice records

Satellites are keeping tabs on the state of Arctic and Antarctic sea ice, and have observed considerable declines in ice extent in many areas since records began, but what do we know of past sea ice extent?

[Gray-Wolf]

Do you think any of the folk making a hullabaloo about ice levels around Antarctica have bothered to look at the ice there ( now we can get a good look as summer approaches)?

 

I've just begun my yearly checks on 'My Crack' ( From Roosevelt island to central Ross) and am quite shocked at just how fragmented the coastal regions, all around the continent , are. Have we had strong outflow from the Centre over the past few months? ( enough to cause such disruption) and how do we think such will impact melt season?

 

For me the 'sweeping clean' that outflow will cause will mean the ice shelf's spend less time protected by the sea ice and more time under the influence of the open ocean. The other point I would make is the lessening of the 'damping' that contiguous ice provides from the impacts of storm swell on the coastal areas.

 

From my quick glance I would think that a lot of the 'outer ice' is now approaching the 15% cut off and so we should expect rapid decline over the next 6 weeks. If we are still seeing ice shoved out from the continent then this rapid decline will continue through Dec and maybe intro Jan? The spots that have been allowing recent 'growth' in min. figures ( seaward of weddell) will also be impacted if this 'melt train' is set into motion.

 

Though a big worry it would be fun if this comes to pass and the misleaders are left explaining a record min come March............where would the next 'Squirrel' come from???

[UV-RAY]

More unsubstantiated assumptions I see GW, let's wait until March before making wild claims. Oh and I still see you posting derogatory remarks about those of us who don't share your comical view on life in general. The ignore button beckons!

[thetonynator]

Do you think any of the folk making a hullabaloo about ice levels around Antarctica have bothered to look at the ice there ( now we can get a good look as summer approaches)? I've just begun my yearly checks on 'My Crack' ( From Roosevelt island to central Ross) and am quite shocked at just how fragmented the coastal regions, all around the continent , are. Have we had strong outflow from the Centre over the past few months? ( enough to cause such disruption) and how do we think such will impact melt season? For me the 'sweeping clean' that outflow will cause will mean the ice shelf's spend less time protected by the sea ice and more time under the influence of the open ocean. The other point I would make is the lessening of the 'damping' that contiguous ice provides from the impacts of storm swell on the coastal areas. From my quick glance I would think that a lot of the 'outer ice' is now approaching the 15% cut off and so we should expect rapid decline over the next 6 weeks. If we are still seeing ice shoved out from the continent then this rapid decline will continue through Dec and maybe intro Jan? The spots that have been allowing recent 'growth' in min. figures ( seaward of weddell) will also be impacted if this 'melt train' is set into motion. Though a big worry it would be fun if this comes to pass and the misleaders are left explaining a record min come March............where would the next 'Squirrel' come from???

This years antarctic winter pattern has been very similar to last years, which resulted in the second highest min on record. I wonder what ''some folks'' who are ''deluded'' and ''misleaders'' will say if that is repeated this season?

[Gray-Wolf]

My initial 'Cryospheric' interest was the Antarctic and 07' rather drew me away from there with the startling changes we witnessed. i have spent over ten years watching the Antarctic ice break up , come spring, and have never seen either the current pattern of break up or the open water we are currently seeing around the coastline.

 

I knew the 'extension' to the ice, north of weddell, was thin but did not know ( though I should have thought!) that it was so 'stretched'. If folk want to hold up an area that appears to have exceeded normal years it is the ice in front of Ross which had been in decline over the winter months since 02' ...... oddly the misleaders have been ignored the areas showing large negative anoms over winter and , as such, have not pointed out this years excess?

 

EDIT: http://www.theage.com.au/environment/animals/dead-birds-not-just-a-freak-event-20131030-2wgzd.html

 

It would appear this is the windiest southern spring since 71'.......odd the last highest ice record was back then?

Edited October 30, 2013 by Gray-Wolf

[Gray-Wolf]

http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=crefl2_143.A2013304035000-2013304035500.250m.jpg

 

This shows the Ross Shelf (and 'My Crack!) illustrating well the way the winter ice has been driven from the coast leaving frazzle (still counted on the extent charts as 'ice cover') alone to dampen any swells hammering into the ice cliffs of Ross.

 

The ice cliffs are undercut by the ocean leaving overhangs prone for collapse. Last years news that the warm water has now made it , from P.I.G. , to Ross will mean that this undercut will be growing faster than ever. When swells are compressed into this undercut pneumatic hammering impacts the ice mass above. Features like the huge fissure from Roosevelt to mid shelf provide natural break points for calving once the undercut approaches.

 

A slice of shelf, as big as the one in danger from collapse on Ross, may well prove enough of a loss to destabilise the whole shelf ( it's ability to buttress against the flow from the interior of EAIS) as the 'rucks' in ice structure, shown in radar scans, warn us of.

 

Whilst misleaders prattle on about seasonal sea ice extensions, bulked out with frazzle, major changes are ongoing in the ice sheet on land (miles thick of grounded, sea level impacting,ice).

Edited October 31, 2013 by Gray-Wolf

[knocker]

Indeed GW.

 

Pine Island Glacier: Plugging Up the West Antarctic Slide

http://www.huffingtonpost.com/nicholas-st-fleur/pine-island-glacier-plugging-up_b_4175293.html

[Gray-Wolf]

Well i feel glad that folk have taken on board my observations and , on checking the images, see no point in trying to 'refute' the current state of the southern spring pack.

 

Though four will love it it does highlight that some measures of ice can be legitimately used to mislead others into believing that something meaningful is occurring in the southern oceans.

 

When I switched my focus to the Arctic basin it annoyed me when I saw a similar tactic used for the ice up there. Though both regions a very different 'ice extent' is measured the same way and is a measure that can be abused by certain folk to try and 'prove' that things are not what they really are.

 

Take the past 6 weeks of Antarctic ice cover. Had we seen healthy ,2m thick, contiguous ice cover from coast to ice edge then the claims made by the misleaders would have been real enough ( though the reasons for the extension would remain the same and believable to me) but to find the kind of 'ice cover' we see there presently being portrayed as something it most certainly is not only intensifies my dislike for the folk parading it as such.

 

We all know that the ice in Weddell has been 'growing' since the late 80's and the scientists looking at this 'growth' have shown us 'why' this is occurring. As this sector of Antarctic Sea ice has grown we have seen decay in other (more important?) areas of the winter ice cover there and these 'losses' seem to be totally overlooked by most folk. Maybe it is time for us to bring up the loss of ice across the Ross Sea and outline why this could spell trouble for the planet?

 

Two things have occurred in the past 6 months that has drawn my gaze back down south. The first is the arrival of the warm bottom waters to the Ross embayment and the other is the reduction in the Ozone hole over Antarctica this spring.

 

If the extension in Sea ice has been helped by the Ozone loss then it's recovery should see those gains slowly fade away. Mass loss would appear to have continued to grow over this same period so maybe focus can once again return to this worrying aspect of climate change?

 

The arrival of warmer bottom waters at Ross is something I have been warning folk about for over 4 years now ( since we saw the damage done to the base of P.I.G. at it's hands). Though the increase in surface winds/currents, over the ozone hole period, had initially kept the warming Southern Ocean from the coasts the past ten years has seen the bottom waters work their way through the ocean floor topography and up to the coast from the peninsula down toward Ross. The winter breakup of Wilkins helped show how important this warm water is to the removal of the ice masses that help buttress against the interior ice flow from the W.A.I.S. Now the full coastal strip of the W.A.I.S. has been compromised and , with it's arrival at Ross, the major E.A.I.S. drain glaciers are now going to see the same 'flow enhancement' that we have measured across W.A.I.S.

 

Past warm interglacial's have seen W.A.I.S. shed most ,if not all, of it's ice well before Greenland has had time to react. This time around we have steadied that process, for over 20yrs, by our messing with the Ozone hole, but have watched Greenland react to the warming ( albedo loss and speed up of drain glaciers). I hope that any mending of the ozone will not lead to rapid changes in the W.A.I.S. as the winds fall slack and allow Southern hemisphere warming back into the continent. With most of the southern hemisphere being water this 'warming' is likely to show impact year round ( and not see the continental 'cool-down' we see across our northern landmasses over winter?

 

EDIT: Thanks knocks! The impacts on PIG will then move around to Ross but the Roosevelt end of Ross forms the inlet that runs through to Weddell. 125 thousand years ago this channel was open and WAIS was ice free and this channel was open water ( as research showed us in the late noughties). We know GHG forcings at that time were similar to today's so , to me, over time we must surely see similar occur. This is not just the worry of the Sea level hike that the loss of WAIS but also the loss of one side of Ross. Ross is part grounded on the sea bed so any 'float off' will fatally reduce it's ability to hold back the EAIS drain glaciers bringing us the prospect of massive sea level hikes ( any rapid rises 'float off' the remaining shelf's allowing unrestricted draining from the whole continent )

 

6 years ago, when I last frequented here I was constantly reassured that EAIS was not in danger from the processes I outlined. It would appear that this is becoming less and less true and all the components needed for a rapid collapse are now coming into place. 

Edited November 1, 2013 by Gray-Wolf

[stewfox]

This years antarctic winter pattern has been very similar to last years, which resulted in the second highest min on record. I wonder what ''some folks'' who are ''deluded'' and ''misleaders'' will say if that is repeated this season?

 

I would certainly expect to see the highest min on record, all things being equal. Given the current area and Volume of sea ice.

 

Whether that's due Increased westerly winds around the Southern Ocean,Increased precipitation, a freshening of the surface layers from this precipitation which increase the local freezing point of sea ice formation.increased melting of Antarctic continental ice or bounds of natural variability. Or as the IPCC suggests """Due to Hades King of the underworld"" remains to be seen.

Edited November 1, 2013 by stewfox

[Gray-Wolf]

I would certainly expect to see the highest min on record, all things being equal. Given the current area and Volume of sea ice.

 

Whether that's due Increased westerly winds around the Southern Ocean,Increased precipitation, a freshening of the surface layers from this precipitation which increase the local freezing point of sea ice formation.increased melting of Antarctic continental ice or bounds of natural variability. Or as the IPCC suggests """Due to Hades King of the underworld"" remains to be seen.

 

Stew, look at the 'mozaic' and see how the ice is being driven from the continent ( to be replaced by a thin skim). Why do you think this would lead to a high min? 

 

To me if you push the ice away from the cold centre and into the warmer ocean you end up melting the ice? If this thicker ice all gets blown into the southern ocean surely this would lead to a record ice min???

 

With the heat we see causing Australia being 'full depth' of the atmosphere and forecasts of another record hot summer there ( based on the anom high ocean temps) surely as summer spreads south so does this anom warmth?

 

I know I've been away from here for a while but surely not that much has changed?

 

As noted in my previous post the warm waters have now travelled from the tip of the peninsula all the way around to Ross ( something I'd been worrying about happening since our 'seals in bath-caps' first measured it on the move nearly a decade ago).

 

Just as an aside do you know how much , as a percentage, the 'extra volume' you are talking about compares to the volume that was lost over the two weeks of the LarsenB collapse back in 02'?

[stewfox]

Stew, look at the 'mozaic' and see how the ice is being driven from the continent ( to be replaced by a thin skim). Why do you think this would lead to a high min? 

 

To me if you push the ice away from the cold centre and into the warmer ocean you end up melting the ice? If this thicker ice all gets blown into the southern ocean surely this would lead to a record ice min???

 

 

 

Apologies it was a bit tongue in cheek,of course you wouldn't expect minimums to increase by wind driven sources for reasons you have stated. We have however seen regular increase of the minimums in recent years.

 

http://sunshinehours.files.wordpress.com/2013/10/antarctic_sea_ice_extent_2013_day_296_1981-2010.png

 

If you look at the animi nation of minimum Antarctica ice since 1980 we can see more 'sea ice' remaining 'around' the whole continent. Why this is so I have yet to find a 'theory'. 

 

http://nsidc.org/cryosphere/sotc/sea_ice_animation_ant.html

 

I find it interesting at latitudes' at just 60 south sea ice can remain, imagine that in the North. 

 

http://www.mapsofworld.com/lat_long/antarctica-lat-long.html

Edited November 2, 2013 by stewfox

[Gray-Wolf]

I think the increase in circumpolar winds/current may have a part to play in this stew? Some of the bergs , from major shelf break off's, have spent 8 years bimbling around the coasts before finally breaking out into the southern ocean proper. Should we see a lessening impact from the ozone depletion then maybe the katabatic winds will win out and serve to shunt winter ice out into the southern oceans over the early part of summer leading to low ice levels by summers end?

 

The problem with watching the Antarctic ( I find) is there is not a lot to see most of the time! Recent improvements in mapping sub surface features and gravity mapping of mass loss has made it easier to accept that changes are occurring there a tad easier but generally things always look 'calm' there.

 

As with the Arctic it's only when things get really dire that change is visible. It took an 07' to have most folk 'see' that changes were ongoing over the Arctic basin even though we had been getting paper after paper pointing out the degradation of the ice there ( esp. the 80's papers on mass loss through Fram?) that showed us the ice was rapidly thinning and 'younging' there .

 

We appear to be getting a similar scale of warning regarding the Pine Island Complex over the past 8 or so years with the most recent survey ( Knock's linked to above) showing the most worrying trend yet to be measured there.

 

P.I.G. is to the West Antarctic Ice Sheet what Ross is to the East. The loss of either means a rapid increase in mass loss from the centre of the ice sheets and very rapid impacts on sea level rises. I still do not think that the loss, or partial loss of Ross ( Roosevelt Island end) is factored into current climate models as it has been viewed as 'safe' from collapse for the next thousand years at least....... I'm not sold on this and neither is a growing body of researchers on Antarctica (esp. when you look at past warm interglacial's that have seen the west Antarctic ice sheet cleared of ice).

 

An ice free w.a.i.s. means an open water channel from Ross to Weddell ( recent fossil evidence supports this) and that means the Roosevelt end of the shelf being absent at such times. Float off of ice shelf's is something else not much discussed but any sudden hike in sea levels would lead to this occurring all around the Antarctic coast where floating shelf's are attached to land based shelf's/glaciers. So I can envisage a 'domino' effect of Pine giving way leading to increased outflow leading to Roosevelt end of Ross ( my 'crack' and beyond) calving and that end of the shelf seeing rapid retreat due to both back pressure overcoming inertia ( due to the losses seaward) and warm water undercutting of grounded sections of the shelf.

 

Radar scans of the back of the shelf seem to pinpoint when the 'brakes' were last slammed on as the shelf glued itself to the sea bed leading to massive 'rucks' in the ice layers as the pressure from the rear met the resistance from the front. Any reduction in that inertia will naturally lead to the same kind of speeds as the two mile thick ice inland squashes out under gravity.

 

I hope it will not take the sight of lost shelf's and newly ice free rock cover to awaken folk to the dangers that Antarctica poses to the planet. It not only holds a lot of water but it is also keeping a fair amount of carbon, buried since the continent last froze, away from our current carbon cycle (just as the permafrost does up north).

[knocker]

Dealing with uncertainty: predicting future sea level rise

http://www.antarcticglaciers.org/glaciers-and-climate/dealing-uncertainty-predicting-future-sea-level-rise/

[BornFromTheVoid]

I'm surprised there are not more posts about this. Antarctic sea ice is continuing it's exceptional record breaking run.

 

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

[stewfox]

I'm surprised there are not more posts about this. Antarctic sea ice is continuing it's exceptional record breaking run.

 

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

 

 

Amazing times we live in.

 

Global sea ice levels still above the long term average

 

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg

[Gray-Wolf]

It reminds me ,very much, of the late spring spurts we saw in the Arctic when the 'ice factory' over the Bering straights turned on? When you look at the coastal strips, and the thin ice there, you can see how we have managed to extend the 'ice season' this year. We see reports from Australia of migrating bird deaths due to them encountering high winds at the end of their journeys ( one of the windiest in years) so we have coasts stripped clean of ice ( which then re-formed 'cause it's still very cold there what with the katabatic winds streaming off the cold interior) and ice 'extent' remaining high as the ice is driven outward.

 

My concern is the 'replacement' ice around the coasts. This late formed ice will not last very long once summer arrives leaving the coasts open to swell and erosion for longer this year. Also the ice driven out from the coasts sill obviously melt out. This might mean that we might see a 'blip' in the ice min this year with a lower figure than we have become accustomed to over recent years.

 

I bet that's another bit of the graph that won't have the normal crew commenting on it as well?

[oldsnowywizard]

GW, just out of interest... as one of the other folk or dis believers... (ie someone who doesnt necessarily see your point of view) ((seriously you have to stop saying things like that, it is a form of bullying)).. you mentioned on here a few times that you thought that the larger ozone hole was one of the factors affecting the higher sea ice levels....so just a question.. with the ozone hole being relatively smaller compared to previous years ( as has been posted before on here a few weeks ago) are you thinking now that the ozone hole doesnt have that big an impact now? or do you think there is some kind of delayed feedback?

 

I do see some of your points,I also have a few of my own thoughts.. for instance I think the record high and record low temps shown also on this link before, would have some kind of impact.. if not stress on the ice .. making it more likely to move... maybe? 

 

I disagree with your last comment...

 

"My concern is the 'replacement' ice around the coasts. This late formed ice will not last very long once summer arrives leaving the coasts open to swell and erosion for longer this year. Also the ice driven out from the coasts sill obviously melt out. This might mean that we might see a 'blip' in the ice min this year with a lower figure than we have become accustomed to over recent years.""

 

surely any ice would help to protect the coasts from the swell and erosion for longer, especially as there is more ice around the continent than before...

[4wd]

Why pretend a record high isn't what it looks like - because AGW theory predicts warmer poles?

 

Seems to me it's a marvel of spin and blinkered viewpoint to even attempt to portray repeated new record highs as a portent of imminent devastating losses.OK some of this ice is now so far out into the Southern Ocean it won't last long, but going on about how it's must be somehow rotten ice compared to what used to be there just sounds ridiculous.No one's trying to make out the records this year are how it's going to be for evermore.Poorly understood or unknown cyclical effects seem the most likely explanation.