Latest Antarctic Ice Reports

[BLAST FROM THE PAST]

Yes, but it wasn't there when I posted, honest guv ! Probably OP put it up while I was editing. But just in case anyone missed it :

The Antarctic maximum winter sea ice area record has been smashed, with the current sea ice area at 16.26 million sq km, beating the previous record of 16.03. Slightly grudgingly admitted on Cryosphere Today.

Amazing really. This concerns me because the reports I posted of the ice thickening and Anarctica cooling over last 30years could be coming true and a very unbalanced Earth with decreased magnetic field...are we in for a wobble?

BFTP

[AtlanticFlamethrower]

Amazing really. This concerns me because the reports I posted of the ice thickening and Anarctica cooling over last 30years could be coming true and a very unbalanced Earth with decreased magnetic field...are we in for a wobble?

BFTP

Why would Antarctic cooling unbalance the Earth?

Your thoughts much appreciated.

[AtlanticFlamethrower]

Nevermind - I understand you probably are referring to an interesting thread started by Jethro on the Environmental Change forum.

[osmposm]

.....Slightly grudgingly admitted on Cryosphere Today.

I've read and re-read the announcement of the new Antarctic ice max on Cryosphere, and simply cannot see what it is they have written that makes you think it is "slightly grudgingly admitted". Other than suggesting that it's a strange season - with which I would agree, since it has encompassed both a new max and a new min at opposite ends of the globe - the statement seems entirely factual.

Perhaps I've missed something, Mr S - could you enlighten me? Or is it just that you assume that any scientific organisation that normally reports palpable evidence of warming must dislike having to mention anything that suggests otherwise - or that is at least less clear-cut?

[Gray-Wolf]

As posted on the other threads in environment there is evidence for a 'pendulum swing' of ice/no ice for the north and south poles (when one melts the other thickens) in the D.O. events. It would seem though that those take hundreds of years to complete whereas this has been a matter of decades........almost as if the planet has the mechanisms to facilitate the change but this time the driver is much more powerful (AGW as opposed to procession).

[BLAST FROM THE PAST]

I've read and re-read the announcement of the new Antarctic ice max on Cryosphere, and simply cannot see what it is they have written that makes you think it is "slightly grudgingly admitted". Other than suggesting that it's a strange season - with which I would agree, since it has encompassed both a new max and a new min at opposite ends of the globe - the statement seems entirely factual.

Perhaps I've missed something, Mr S - could you enlighten me? Or is it just that you assume that any scientific organisation that normally reports palpable evidence of warming must dislike having to mention anything that suggests otherwise - or that is at least less clear-cut?

Find a news article on the record ice extent of Antarctica. Now find one on the record minima of the arctic. Bet the latter is much easier and widely more reported on but both as important as each other.

BFTP

[Mr Sleet]

Find a news article on the record ice extent of Antarctica. Now find one on the record minima of the arctic. Bet the latter is much easier and widely more reported on but both as important as each other.

BFTP

Googled it BFTP, and you are right. Try telling anyone that Antarctica contains 90% of all the worlds ice too, and see what response you get

I've read and re-read the announcement of the new Antarctic ice max on Cryosphere, and simply cannot see what it is they have written that makes you think it is "slightly grudgingly admitted". Other than suggesting that it's a strange season - with which I would agree, since it has encompassed both a new max and a new min at opposite ends of the globe - the statement seems entirely factual.

Perhaps I've missed something, Mr S - could you enlighten me? Or is it just that you assume that any scientific organisation that normally reports palpable evidence of warming must dislike having to mention anything that suggests otherwise - or that is at least less clear-cut?

Hi Osm. I did say slight Call me a cynic, but it was the way they made it clear that the records only went back to -79

( inference- unreliable) and followed the bit on Antarctica immediately with a reiteration about the Arctic ( inference - defensive posture).

With that site it's also words like Arctic ice minimum " annihilated"; , a term which suggests that the author is a bit emotional. When people get emotional they start to lose their sense of objectivity. Reading between the lines I see a lack of objectivity in their line of thinking when presented with something which is unexpected and goes against their grain.

However, it's just a personal observation which others might not see.

Edited September 14, 2007 by Mr Sleet

[AtlanticFlamethrower]

As posted on the other threads in environment there is evidence for a 'pendulum swing' of ice/no ice for the north and south poles (when one melts the other thickens) in the D.O. events. It would seem though that those take hundreds of years to complete whereas this has been a matter of decades........almost as if the planet has the mechanisms to facilitate the change but this time the driver is much more powerful (AGW as opposed to procession).

This sounds like gobledygook to me, and not through my lack of understanding.

[Stratos Ferric]

Hmmm ... may have to redraw the zone of sound Northern thinking, anyway you hail from E Anglia don't you, so do you qualify in the ZoSNT?

...

said the man who lives perilously close the the mysterious southern zone of wishful thinking.

Find a news article on the record ice extent of Antarctica. Now find one on the record minima of the arctic. Bet the latter is much easier and widely more reported on but both as important as each other.

BFTP

That's a bit like Googling stories regarding the premiership of Tony Blair vs that of Gordon Brown though Blast. The news re Antarctica only broke on Wednesday.

I agree with the sympathy of your argument, but there's a couple of points to bear in mind. One, far more people live close to the Arctic, so it feels more immediate. Two, the loss of Arctic sea ice is more dramatic; let me clarify what I mean. It is now possible to postulate, without seeming ludicrous, that in the not too distant future the NH will be ice free in summer. That's more striking that a bit of variation here or there. The difference between having, and not having, is much more compelling than the same absolute variation but between, say, 13m km2 and 16m km2. Also, the total loss of ice in the NH has all sort of implications for circulation of both air and water; the Antarctic ice has implications much more for sea level.

Yes, but it wasn't there when I posted, honest guv ! Probably OP put it up while I was editing. But just in case anyone missed it :

The Antarctic maximum winter sea ice area record has been smashed, with the current sea ice area at 16.26 million sq km, beating the previous record of 16.03. Slightly grudgingly admitted on Cryosphere Today.

I'm not sure I'd used "smashed". The variation is much smaller than at the Northern Pole, both in absolute terms (about 1m km2 at the north pole, currently about a quarter of this at the south), but particularly in relative terms (around 25% at the North Pole, around 1.5% at the South). Perhaps you'd like to suggest an appropriate label for what's happeneed in the arctic, using 'smashed' as the baseline, but which reflects the order of magnitude difference in relative scale. What's biger than smashed? "Nuked out of sight"?

[BLAST FROM THE PAST]

That's a bit like Googling stories regarding the premiership of Tony Blair vs that of Gordon Brown though Blast. The news re Antarctica only broke on Wednesday.

I agree with the sympathy of your argument, but there's a couple of points to bear in mind. One, far more people live close to the Arctic, so it feels more immediate. Two, the loss of Arctic sea ice is more dramatic; let me clarify what I mean. It is now possible to postulate, without seeming ludicrous, that in the not too distant future the NH will be ice free in summer. That's more striking that a bit of variation here or there. The difference between having, and not having, is much more compelling than the same absolute variation but between, say, 13m km2 and 16m km2. Also, the total loss of ice in the NH has all sort of implications for circulation of both air and water; the Antarctic ice has implications much more for sea level.

SF

I see where you are coming from but Antarctica is of massive/global importance. I personally think both results are as important as each other but it may suggest that my assertion that ocean warming is the culprit here as air temps aren't doing it for me. I think ice/glacier thickening and advancement due to a 30 year cooling in the Antarctic is having its effect down there now. Let's see how the reports come...but I think they won't come. I do take all your points though.

BFTP

[AtlanticFlamethrower]

The variation is much smaller than at the Northern Pole, both in absolute terms (about 1m km2 at the north pole, currently about a quarter of this at the south), but particularly in relative terms (around 25% at the North Pole, around 1.5% at the South).

There are increasing marginal returns* to ice growth in warm water. The rate of ice loss in warm water becomes exponential as the mass descreases. It is a fallacy to compare the rate of melt and freeze in the Arctic and the Antarctic as if the physics were equivalent.

This is obvious if you try to imagine a 27% ice gain in sea ice in Antarctica - which (at over 4m km2) would be more additional sea ice than exists in the Arctic.

An extra 230k sea ice at the South Pole is arguably as impressive as a 750k ice loss at the North Pole because on planet Earth when you get to an area the size of 16.2m km2 every extra bit becomes that much harder to freeze.

Now I've made you honest, perhaps you can provide the proper statistical formula for this.

*As it expands, an ever-larger surface area of the Antarctic ice cube is exposed to the warm waters of the Southern Ocean. Since the Antarctic is not surrounded by continents all cold air to freeze the sea must come from the pole region outwards.

Edited September 14, 2007 by AtlanticFlamethrower

[Mr Sleet]

said the man who lives perilously close the the mysterious southern zone of wishful thinking.

That's a bit like Googling stories regarding the premiership of Tony Blair vs that of Gordon Brown though Blast. The news re Antarctica only broke on Wednesday.

I agree with the sympathy of your argument, but there's a couple of points to bear in mind. One, far more people live close to the Arctic, so it feels more immediate. Two, the loss of Arctic sea ice is more dramatic; let me clarify what I mean. It is now possible to postulate, without seeming ludicrous, that in the not too distant future the NH will be ice free in summer. That's more striking that a bit of variation here or there. The difference between having, and not having, is much more compelling than the same absolute variation but between, say, 13m km2 and 16m km2. Also, the total loss of ice in the NH has all sort of implications for circulation of both air and water; the Antarctic ice has implications much more for sea level.

I'm not sure I'd used "smashed". The variation is much smaller than at the Northern Pole, both in absolute terms (about 1m km2 at the north pole, currently about a quarter of this at the south), but particularly in relative terms (around 25% at the North Pole, around 1.5% at the South). Perhaps you'd like to suggest an appropriate label for what's happeneed in the arctic, using 'smashed' as the baseline, but which reflects the order of magnitude difference in relative scale. What's biger than smashed? "Nuked out of sight"?

Could I suggest that Arctic ice discussions are kept to the Arctic ice thread ? The mods created this thread specifically because the arctic thread was becoming contaminated with antarctic posts, lets not contaminate this thread too. You'll just have to resist the temptation to bite.

Edited September 14, 2007 by Mr Sleet

[BLAST FROM THE PAST]

Could I suggest that Arctic ice discussions are kept to the Arctic ice thread ? The mods created this thread specifically because the arctic thread was becoming contaminated with antarctic posts, lets not contaminate this thread too. You'll just have to resist the temptation to bite.

There was no bite involved. There is every chance the two topics will cross and be relevant. Surely???

BFTP

[Stratos Ferric]

...but it may suggest that my assertion that ocean warming is the culprit here as air temps aren't doing it for me. I think ice/glacier thickening and advancement due to a 30 year cooling in the Antarctic is having its effect down there now. Let's see how the reports come...but I think they won't come. I do take all your points though.

BFTP

I certainly don't disagree re the sea temperatures being a predominant factor. As to what's causing Antarctica to grow, I think, as we've debated on here before, it's a complicated mixture, exacerbated by a paucity of hard data and a shorter historical record than in the Arctic.

There are increasing marginal returns* to ice growth in warm water. The rate of ice loss in warm water becomes exponential as the mass descreases. It is a fallacy to compare the rate of melt and freeze in the Arctic and the Antarctic as if the physics were equivalent.

This is obvious if you try to imagine a 27% ice gain in sea ice in Antarctica - which (at over 4m km2) would be more additional sea ice than exists in the Arctic.

An extra 230k sea ice at the South Pole is arguably as impressive as a 750k ice loss at the North Pole because on planet Earth when you get to an area the size of 16.2m km2 every extra bit becomes that much harder to freeze.

Now I've made you honest, perhaps you can provide the proper statistical formula for this.

*As it expands, an ever-larger surface area of the Antarctic ice cube is exposed to the warm waters of the Southern Ocean. Since the Antarctic is not surrounded by continents all cold air to freeze the sea must come from the pole region outwards.

AFF, I wasn't arguing the physics, I was arguing the maths. You can rationalise it all you like (and your arguments seem very sound) but te fact is the the total net ice surface is smaller, meaning the earth's albedo is slightly lower as a conseqence.

The corollary to your final point is that not only is there no continental cold air, neither is there continental warm air. The entire southern circulation is very different, and is precisely why, together with the continental nature of Antarctica, southern ice will endure for longer than northern ice.

[AtlanticFlamethrower]

AFF, I wasn't arguing the physics, I was arguing the maths. You can rationalise it all you like (and your arguments seem very sound) but te fact is the the total net ice surface is smaller, meaning the earth's albedo is slightly lower as a conseqence.

What am I rationalising? All I've said was that the Antarctic ice growth is significant.

You want to talk about a purported feedback mechanism rather than conditions as they are now which have actually determined the rate of melt/ice growth at the poles.

If we ignore albedo and just look at the facts then the Antarctic record high looks very impressive, do you not agree?

[oldsnowywizard]

what is impressive is ...

http://arctic.atmos.uiuc.edu/cryosphere/IM...t.365.south.jpg

the record high sea ice levels especially when August had about 3 and a half weeks of next to nothing ice gain! does anyone know the reason for the sudden surge in sea ice levels? - i havent noticed any particular sudden expansion of cold pools? it would be interesting if anyone could dig out any ice thickness charts for the Antartic...(if they exist?) with another month of possible sea ice production left the question is can we reach the 17m mark? i can see 16.5...

very impressive.

[biffvernon]

Trying to work why Global warming is eating the Artic for breakfast while down the other end we're now having record highs.

Quite different geographies. Arctic is almost landlocked ocean, Antarctic is ocean surrounding landmass. Antarctic sea ice is very variable in extent from year to year and the slight increase in recent years is hardly statistically significant. Global warming may increase snowfall on the developing Antarctic sea ice adding to thickness so expansion of ice is to be expected. There's very little snowfall in the Arctic 'desert' More info on this at NSIDC

[Stratos Ferric]

Quite different geographies. Arctic is almost landlocked ocean, Antarctic is ocean surrounding landmass. Antarctic sea ice is very variable in extent from year to year and the slight increase in recent years is hardly statistically significant. Global warming may increase snowfall on the developing Antarctic sea ice adding to thickness so expansion of ice is to be expected. There's very little snowfall in the Arctic 'desert' More info on this at NSIDC

That would be my my hypothesis, though with a caveat. The anual anomaly plots this year show Antarctica preety much consistently running 5-10C above the norm; obviously still well below freezing in absolute terms, but a big difference and enough to increase considerably the moisture bearing potential of the air.

The caveat, though, is that even with heavier snowfall in the interior (and I don't think we'd be talking a difference in temrs of tens of metres by the way, it would be a small increase, ny guess would be less than a metre), this would not work its way to the exterior in a matter of months. The answer must be one of two things (perhaps three, actually, nd possible a combination).

1 - Offshore SSTs have fallen - perhaps there have been subtle changes in currents, leading to some cold-upwelling: against this, this could not be expected to be the case right around the continent;

2 - Changed synoptics - an increased preponderance of southerly winds during the winter. I haven't checked but this would be consistent with the occasional unusual low temps recorded in some locations in the SH. It is possible that no.2 could help drive no.1, but still not to the extent that the impact was seen right around the continent - at least not without the most unlikely series of coincidences;

3 - Increased melt and run-off has reduced surface salinity in the near shore ocean and enabled the sea to freeze more easily. Related to this, a reduction in mean wind speed would also have a similar effect.

[Stratos Ferric]

What am I rationalising? All I've said was that the Antarctic ice growth is significant.

You want to talk about a purported feedback mechanism rather than conditions as they are now which have actually determined the rate of melt/ice growth at the poles.

If we ignore albedo and just look at the facts then the Antarctic record high looks very impressive, do you not agree?

AFF, by definition, any structured argument is a rationalisation. What you have suggested was that the gain in Antarctica was as impressive as the loss in the Arctic. Of course 27% in Antarctica would be more than 27% in the Arctic. The ice base in the former is four times larger at this time of year. However, we were talking about ACTUAL increase / decrease. At the time of starting the discussion the Arctic was around 2m km2 down, Antarctic was 1m km2 up. The net total globally is down, by about 1m km2 on the norm. I can't see what point you're trying to make, these are the numbers, there's nothing to be keeping me 'honest' about, though I respect the challenge and the need for clarification.

In a way, as I think I said, the growth at the margins of Antarctica is, on the face of it, 'impressive' because as the ice expands it is, all other things being equal, running into warmer air and water (clearly this cannot be the fact because ice would not then be forming). However, sauce for the goose and all that, the same is true in reverse in the Arctic: the more the ice recedes, the harder in theory it should be to recede further, because it is reaching ever colder waters and air. Again, that clearly can't be the case otherwise it wouldn't melt. If gain in the Antarctic is "impressive", then the same adjective at least needs to be applied to the loss at the other pole.

Feedback does matter because, as anyone who has watched snow on a mountain melt, once a dark surface is opened up much more energy is absorbed into the system. The same is true in reverse. Melting and freezing to some extent develop a momentum of their own (and, indeed, this would HAVE to be the case otherwise we could never have ice ages)

[Gray-Wolf]

That would be my my hypothesis, though with a caveat. The anual anomaly plots this year show Antarctica preety much consistently running 5-10C above the norm; obviously still well below freezing in absolute terms, but a big difference and enough to increase considerably the moisture bearing potential of the air.

The caveat, though, is that even with heavier snowfall in the interior (and I don't think we'd be talking a difference in temrs of tens of metres by the way, it would be a small increase, ny guess would be less than a metre), this would not work its way to the exterior in a matter of months. The answer must be one of two things (perhaps three, actually, nd possible a combination).

1 - Offshore SSTs have fallen - perhaps there have been subtle changes in currents, leading to some cold-upwelling: against this, this could not be expected to be the case right around the continent;

2 - Changed synoptics - an increased preponderance of southerly winds during the winter. I haven't checked but this would be consistent with the occasional unusual low temps recorded in some locations in the SH. It is possible that no.2 could help drive no.1, but still not to the extent that the impact was seen right around the continent - at least not without the most unlikely series of coincidences;

3 - Increased melt and run-off has reduced surface salinity in the near shore ocean and enabled the sea to freeze more easily. Related to this, a reduction in mean wind speed would also have a similar effect.

I've posted on the Enviro thread but feel more folk venture into here than 'the other place'.

4/ The loss of large areas of shelf/glacier snout leading to 'extra open waters' to be included in the total. Remember the size of Larsen B or B15? The calcs do not use Ice Shelf/Glacier Snout extensions and have their 'coast' set at the last years min. figure. Anyone else noticed this measuring anom?

[AtlanticFlamethrower]

Quite different geographies. Arctic is almost landlocked ocean, Antarctic is ocean surrounding landmass. Antarctic sea ice is very variable in extent from year to year and the slight increase in recent years is hardly statistically significant. Global warming may increase snowfall on the developing Antarctic sea ice adding to thickness so expansion of ice is to be expected. There's very little snowfall in the Arctic 'desert' More info on this at NSIDC

I thought global warming meant higher SSTs, more storms to break up the ice, and higher air temperatures that would melt ice even in winter.

Now global warming means more Antarctic sea ice - it's an infallible theory.

Yes, increased snowfall would result in greater thickness and expansion of sea ice. It's a plausible mechanism and might well be right. Glad you mentioned it - I learned something new.

However - here is an equally plausible positive-feedback mechanism that could explain the Antarctic ice-expansion with snowfall, and it will happen even without global warming.

As the Antarctic ice-edge expands - due to cold - it pushes further toward warmer, moisture ladened air in the tropics. The larger the Antarctic ice-belt is the deeper the well of moisture can be tapped for precipitation, which will more often fall as snow, increase ice-thickness and cause the ice-edge to push on further still to ever more moisture ladened air (until it can go no further - ever decreasing marginal returns).

Since the temperature record shows the Antarctic has not been warming one must presume this is the process by which the Antarctic winter ice record has been broken.

Which is significant.

Edited September 16, 2007 by AtlanticFlamethrower

[AtlanticFlamethrower]

the same is true in reverse in the Arctic: the more the ice recedes, the harder in theory it should be to recede further, because it is reaching ever colder waters and air.

No it's not equivalent - melt occurs in the summer. Sun in the sky 24/7; the air and waters are at their warmest.

Ed: actually you're right. very interesting comment. It is equivalent and it would indicate that the Arctic ice-loss so far is not that historically significant- because we're far from decreasing marginal returns from melt. Still some way to go. But that's for another thread.

Ed: Again - actually I might change my mind again - am I allowed? I wonder whether the fact the artic is surrounded by heat stores - continents - would make the air much warmer in the Arctic during summer than it can get cold in an Antarctic winter due to the heat source of the Southern Ocean.

Got that?

Anyone still reading?

:: Echo ::

Edited September 17, 2007 by AtlanticFlamethrower

[Stratos Ferric]

...

Since the temperature record shows the Antarctic has not been warming one must presume this is the process by which the Antarctic winter ice record has been broken.

Which is significant.

Well, something doesn't stack up AFF, because the anual anomalies I've seen all show Antarctica generally at 5-10C above the norm.

Your feedback theory would be fine but for the fact that the thermal energy in the oceans is far greater than the thermal energy in the air above.

On the other hand, increased interior snowfall cannot account for increased ice mass at the margins unless the snowfall has been phenomenal. The increase in continental mass would take decades to feed through to increased flows. I'd hasard that the likeliest explanation this year is synoptics giving off shore winds, though this couldn't be true right around the continent, and any net increase in some places would have to more than compensate for reductions in others.

No it's not equivalent - melt occurs in the summer. Sun in the sky 24/7; the air and waters are at their warmest.

Ed: actually you're right. very interesting comment. It is equivalent and it would indicate that the Arctic ice-loss so far is not that historically significant- because we're far from decreasing marginal returns from melt. Still some way to go. But that's for another thread.

Ed: Again - actually I might change my mind again - am I allowed? I wonder whether the fact the artic is surrounded by heat stores - continents - would make the air much warmer in the Arctic during summer than it can get cold in an Antarctic winter due to the heat source of the Southern Ocean.

Got that?

Anyone still reading?

:: Echo ::

Yes, but then the reverse would be true in winter by the same logic. The main factor re the Arctic is probably the NAD, which will produce net warmth all year around on one side of the Arctic.

[AtlanticFlamethrower]

Feb 2007

Last year, Bromwich's research group reported in the journal Science that Antarctic snowfall hadn't increased in the last 50 years. "What we see now is that the temperature regime is broadly similar to what we saw before with snowfall. In the last decade or so, both have gone down," he said.

Sample Antarctic station temperature record.

Your feedback theory would be fine but for the fact that the thermal energy in the oceans is far greater than the thermal energy in the air above.

So, only global warming - increased snowfall - can produce sea ice positive anomalies? Something about that doesn't make sense. Don't know what it is.

The oceans provide the moisture which falls as snow. The higher thermal energy in the oceans is places a logarithmic limit on sea ice extent. Antarctic is near that limit now.

Yes, but then the reverse would be true in winter by the same logic. The main factor re the Arctic is probably the NAD, which will produce net warmth all year around on one side of the Arctic.

Winter should be colder in the Arctic but it's not because the continents allow the cold to spread further south - presumably through weather patterns you don't get in the southern hemisphere. The Antarctic has colder winter temperatures because the cold is more concentrated. That's why the same amount of global warming matters much less for Antarctic ice - Antarctic temperature has much lower baseline from which to rise.

Perhaps there are weather patterns whereby the Antarctic cold becomes less concentrated and spreads out some years and thus helps create more sea ice? This would be independent of global warming, and could be accompanied by negative anomalies as more cold floods north. Though not to deny global warming either even though GW is not obvious from the Antarctic temperature record re: Science article (perhaps due to these weather patterns).

Edited September 17, 2007 by AtlanticFlamethrower

[Roger J Smith]

The actual extent of Antarctic ice cover can be seen on this global SST map:

I believe that the anomalous ice cover is located mainly on the Atlantic side of the southern hemisphere. As this is near the seasonal max at the end of southern winter, this probably points to a weaker storm track across the regions around the Antarctic peninsula in the past few months.

Just a few comments about the climate of Antarctica for the benefit of those who may not be that familiar with it. The continent is largely elevated well above 1,000 and even 2,000 metres, much like Greenland, so temperatures in the southern winter dive down to extremely low levels there. Current readings are between -20 or -30 near the coast, to -70 C in the deep interior. The pole of cold is located somewhat to the African side of the south pole due to geography, but essentially, Antarctica could warm up considerably and not be in much danger of losing ice in 95% of its terrain, only the marginal areas like the Antarctic peninsula and the Ross Sea are currently under any real threat of melting. And as some have speculated here, with a slight warming you could easily get more snowfall and thus more ice formation over the continent.

As for the sea margins, this area is subjected to the almost constant passage of very deep low pressure areas so that the ice margin can only advance if storminess moves further north or weakens substantially. The wind and wave action alone would prevent the southern ice from making very much progress northwards even if temperatures over the ice pack dropped, and normally they don't fall much below about -5 to -10 C around this region.

The matter of the asymmetric polar ice fluctuations is not that surprising, historically there have been global climate changes in sync and also of opposite sign from one polar region to the other, so there is no set pattern in this regard. You can see from the SST maps how considerable amounts of unusually cool water are flowing away from the ice margins in the southern hemisphere and circulating into both the Pacific (this is the strong La Nina avent) and the South Atlantic to a lesser extent. Of course these are not cold waters by the time they reach the equator, and if the southern circulation increases in equatorward negative heat transport, this could be reflected after a lag time in poleward heat transport in the northern hemisphere. This does not appear to be happening yet, the main feature in the northern hemisphere is the warmer than normal water seemingly flowing away from eastern Asia and up through the Bering Straits into the Arctic Ocean around Wrangel Island and northeast Siberia.

__________________

That link to SST maps, produced every 3-4 days, is

osdpd.noaa.gov/PSB/EPS/SST/data/anomnight.9.13.2007.gif

Edited September 17, 2007 by Roger J Smith