Arctic Ice Discussion

[Gray-Wolf]

It's a worry Ice! Even with such a slow start to the season we look to be second lowest (tied with 3 other years presently which will drop to 2 by tomorrow if we have any melt today!) in the JAXA series.

Anyone looking at the Modis images will see some areas of very disrupted ice (why Jaxa numbers have had such large revisions of late?) which will certainly make a dent in extent when the melt out.

Ice thickness has been my beef all winter and the IceBridge data from the Beaufort sea transept does not make me rest any easier. If that is 20cm thinner than last years (which was all gone by Aug) when will it melt out this year?

The earlier the open water appears the more heat is absorbed and the greater the knock on effects become in Autumn/early winter. I'm now debating whether the loss of ice itself or it's near immediate impacts on the weather will be the main talking points over the next few years?

[Iceberg]

June is certaintly the pivotal month if we see strong melt it makes it very difficult for the rest of the season to finish on anything decent unfortunately.

Looking at the arctic blocking and forecasts though at least the begining of June will be ripe for synoptic melting even with a normal arctic pack, with what we have left it starts to get worrying as I had hoped(if not expected) that we would be in a slightly stronger position by now.

[Gray-Wolf]

I think many folk fall into the 'trap' of looking at the ice cover ( at max) and not seeing any huge alterations to it over the years? Without knowing the ice age/thickness (I think over 3 years and greater than 2m is what we need?) it is hard to imagine how the pack will react over an 'average melt season'.

It's common sense to say that, all other things being equal, a thinner pack will melt out faster than a thicker pack. The remaining issue seems to be the timing for that melt out? The earlier it melts the longer we have dark water absorbing the sun's energy. By June 21st we could really do with there still being a lot of ice cover to 'bounce' that energy back into space but this year it looks as though we may have record amounts of 'dark water' for the 6 weeks past solstice.

As an aside I've been reading about the impacts that the polar vortex may have on ENSO (and the Arctic Amplifications impacts on the polar vortex). Should we have a lot of ice loss this summer (and these folk are correct) then we should see a very short 'neutral' phase with this past winters ends strong vortex over Alaska/Canada pushing us back into an El Nino by the start of winter.

I mention this as it may have many wide ranging impacts on other 'cycles' down the line (PDO being one that springs to mind?). If summer ice loss can start to push us into other warm phases of cycles then we have a very large feedback mechanism already in it's infancy with the potential to over-ride the 'natural' cooling mechanisms our natural cycles bring?

Edited May 25, 2011 by Gray-Wolf

[VillagePlank]

<snip>

Edited May 25, 2011 by Sparticle

[The PIT]

Third lowest at the mo but it looks like the ice will be still there at the end of summer.

[Geordiesnow]

Third lowest at the mo but it looks like the ice will be still there at the end of summer.

Of course the ice will still be there by the end of summer but the worry at the moment is that we could potentially head for the lowest extent minimum and lets be honest, the sat images and extent graphs do not look good at the moment.

It does look like we will get some colder air over the Canadian/Alska areas where its been ridiculasly mild for quite a while now but at the same time, where its been fairly cold recently on the Russian side, there will be more very mild air heading this way in the coming days.

One thing I have noticed so far this year is the amount of very mild that has entered the Arctic so far - Again, does not bode well for the rest of summer and thats before we factor the more technical side of things.

Whilst it is a concern at the moment, its a wait and see process and we will know the results by September.

[Gray-Wolf]

I wish my half empty glass was as half full as Pits!!!

2nd lowest by the way! and that on the back of some mediocre melt days.......Since 07' I've been posting about the extent should we have a low start point to the melt season (every year since 07' has been quite 'plump' come max extent) so I guess my fears are being realised this year?

Yes G.S., some of the temps have been quite elevated, Hudson bay (with it's late forming skimpy ice) has been very mild for the past week so I'd expect it's ice to do one come mid June (pretty ragged there now).

And 'Yes', we won't know the final min until Sept but those of us with concerns will try to illustrate them better by being correct in our forecast for ice loss so more folk might take not of our concerns?

[jethro]

Thought some of you may find this site interesting:

http://neven1.typepad.com/blog/2011/05/ice-age.html

[Gray-Wolf]

Thought some of you may find this site interesting:

http://neven1.typepa...05/ice-age.html

I pop in there quite often, some of the 'comments' are very useful/informative regarding the ice and it's behaviour. I also find this Blog quite informative to;

http://www.science20...atrick_lockerby

Well worth reading back over last years 'Arctic' conversations too.

Back to the melt! is today the first 100k loss this year?

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

As I have mooted with the amount of smashed up pack across the pole at present we should start to see these big losses become common over the coming weeks.

The true test will be how the melt slows in late July/Early Aug.

In past years we have had a backbone of resilient Paleocrystic ice to fight off the attentions of summer warmth, in even more recent time we've had the same collapsing to provide us with prof Barbers 'rotten ice' but 'plumping up ' the extent figures as it did.

Not so this year! all we have is sub 5yr ice with a low average thickness.

If the weather plays it's part we could see a June like melt speed right up to Sept and that will not leave us with much ice at all.

Edited May 26, 2011 by Gray-Wolf

[The Future]

Hello

Can anyone explain why these do not match?

DMI/COI (select anomalies)

Unisys (select anomalies)

The first one seems more in line with the sea ice melt.

[Rob]

Because all data related to global warming is corrupt

[stewfox]

The true test will be how the melt slows in late July/Early Aug.

If we get more open water,early on and all that sun light gets absorbed rather then reflected back by the ice should we expect more residual heat to off set any slow down in the melt until Mid August ?

[jethro]

If we get more open water,early on and all that sun light gets absorbed rather then reflected back by the ice should we expect more residual heat to off set any slow down in the melt until Mid August ?

Loss of albedo means more energy absorbed but no ice cover means more heat radiated away - I don't think anyone knows the answer to that balancing act.

[Gray-Wolf]

Loss of albedo means more energy absorbed but no ice cover means more heat radiated away - I don't think anyone knows the answer to that balancing act.

Wish i had your optimism J!

As it is I see a very worrying trend with no reason to think that it will reverse any time soon? I also see certain areas of that system being destroyed so there is no chance of any 'return' like the permafrost coastlines now subjected to ocean processes now that the fast ice has gone or the loss of methane/CO2 from the submerged permafrost off Siberia or the destruction of the ice nurturing 'halocline' layer across many areas of the basin?

Back to todays ice, the IJIS shows us less than 60k from the bottom of the bunch with a real possibility of falling to the lowest for the time of year in the IJIS series (which I believe would put it lowest for the time of year since records began?). Couple this with the fact that most of the melt is occuring from below we're left wondering how fast it'll start to completely melt out? We know that Beaufort went in July last year , we also know that the transept flown by NASA's IceBridge mission shows the ice 20cm thinner there than last year (which was thinner than the year before) so given the average conditions we saw last year I'd expect this ice to go earlier this year?

Back to J's 'radiation' of accrued heat.

If the past 2 winters were really driven by that 20c anom over sectors of the Arctic Ocean then surely the larger the areas losing heat in late Autumn the bigger it's potential to mess with the atmospheric circulation above?

I've also been reading some commentators views on the late,strong Polar Vortex over Canada/Alaska late last winter and it's influence on both the Ozone losses (record high loss) and ENSO (via teleconnections). Should we be locked into ice loss (thickness and min extent) then we can expect a 'new' winter synoptic from now on?

This then surely has impacts on the rest of the years synoptics via a 'butterfly's wing' type process of knock on impacts/

Interesting times. One of the reasons I favour studying the Arctic System above other systems around the Globe is the prediction that AGW effects will manifest there first and have a greater impact there. If we still need to convince folk of the dangers of AGW then , to me, our best chance of showing this will be by the changes we are witnessing in the Arctic.

[Gray-Wolf]

As an add on to the above .Nobody wishes to see the changes I envisage (least of all me!) and we cannot blame our generation for the damage being done (that will be for our children and their children!) so we should not baulk from acceptance because we cannot bare the 'blame', the damage was done in ignorance of it's impacts on the future generations.

Back to today. Is Nares 'Bridge' now 'failing down'? There has (though the clouds) been a carbuncle on that beautiful scallop ice front these past two days and that (as of the 19:25 MODIS image) fallen off. Maybe by tomorrow we'll have a better idea. I've never know a summer where open water to the north of an ice bridge looked likely to travel south to smash the blockage but this year it looks likely to be the case! With temps still low there the 'carbuncle' may well have been freshwater outflow from the glaciers beyond flowing off the 'Bridge' to re-freeze (like a frozen waterfall?) in front of the 'Bridge'. It appears that this feature has now fallen off the 'Bridge'.

Can anyone seek to reassure me that the basin will not suffer massive ice loss this summer? I've tried my hardest to see the glass half full (via Pit) but worry overly about the 'thin ice' we are on and the experience of the past 2 summers (and 3 winters) that the once 'positive synoptics' for ice retention are now working in favour of ice loss...along with the synoptics for ice loss. I tended to be pleased at the cold start to the melt season that Canada/Alaska had had but this would appear to be at the cost of the Siberian/Bering side of the Basin with basal melt continuing whatever the temps above. I have used Nares as a 'positive' but now that this appears to be failing I'm again a tad despondent.

Edited May 31, 2011 by Gray-Wolf

[Thundery wintry showers]

A recent paper in Geophysical Research Letters by Tietsche et al. (Jan 2011) titled "Recovery mechanisms of Arctic summer sea ice" casts doubt on the existence of a "tipping point" for Arctic sea ice (though again the Greenland ice sheet might be a different story) with a climate model simulation suggesting that the excess heat from melting summer sea ice is radiated away during autumn and winter and that the summer sea ice typically starts to recover within two years, thus making summer sea ice depletion reversible. Interesting stuff, and I believe it's also highly relevant to what Jethro said.

However, I recall coming across another study (Miller et al. 2010 in Quaternary Science Reviews) suggesting that we are likely to continue to have a significant Arctic Amplification (some 3-4C rise for every 1C rise in global temperature), so we may still be screwed even if it is entirely reversible.

[jethro]

I still fail to see or understand the intense concern over sea ice levels - if interior ice caps like Greenland loose vast amounts of ice quickly, then and only then will I consider there is need for great concern. Even then, that concern would only be for rising sea levels and what mitigating action we as a species would need to take.

The entire purpose of climate patterns changing is to moderate the climate. The extent of Arctic ice is dependant upon heat from the Tropics being dispersed Northwards, if there is extra heat in the Tropics, there will be less ice. Diminishing ice levels are simply symptomatic of a climate system working properly and efficiently - it is doing exactly what it is supposed to do. The fact that it is doing it in our time and that we have knowledge that we have probably contributed to it, doesn't alter the fact that the system is working and working well. There is nothing to suggest that anything untoward is happening other than a possible speeding up of the process, that is entirely to be expected. We will reach a new and possibly different equilibrium than we personally have experienced, but that doesn't make it wrong and it certainly doesn't make it dangerous.

As a poster for CO2 impact upon climate, Arctic ice level serves a good purpose but like much in our media driven world, it shouldn't be taken at face value.

[Thundery wintry showers]

The balance of research suggests to me that the Arctic Amplification does not fuel global warming, only regional changes within the Arctic itself, but that global warming does fuel the Arctic Amplification. Thus, I think that ultimately what we need to be concerned about is the rate and total magnitude of mean global temperature rises, because the more/faster global warming we get, the more rapid and substantial the changes in the Arctic will be- this includes the melting of the Greenland ice sheet which, for me, is by far the biggest worry.

[jethro]

The balance of research suggests to me that the Arctic Amplification does not fuel global warming, only regional changes within the Arctic itself, but that global warming does fuel the Arctic Amplification. Thus, I think that ultimately what we need to be concerned about is the rate and total magnitude of mean global temperature rises, because the more/faster global warming we get, the more rapid and substantial the changes in the Arctic will be- this includes the melting of the Greenland ice sheet which, for me, is by far the biggest worry.

Agreed.

What has to be considered is that now and in the future, measures are and will continue to be taken, to reduce CO2 emissions. This coupled with the known science of the laws of physics governing how great the impact CO2 can and will have on the atmosphere, the only real unknown is positive feedback. The primary concern and the basis for the initial and subsequent assessment of likely impact have been utterly reliant upon the dramatic amplification of warming due to water vapour - there is scant empirical evidence for this. There have numerous studies both complete and on-going upon clouds and the hydrological cycle, some conclude in favour of the positive feedback, some conclude the net impact is a negative one - there are none so far which support the first assumed positive amplification.

So much of the initial research seems to have been based upon "assume the worst case scenario", this was taken as the starting point in order to wake the world up to the situation and force remedial action via emission reductions - a clean up your act or else stance. It's worked, the world has been forced to sit up and take notice but the worst case scenarios were never more than scare tactics with scant attention paid to empirical evidence; instead an almost complete dependence upon theoretical models with incomplete data input due to lack of knowledge.

The new research and knowledge which has flowed since, paints a far more realistic and far less dramatic picture of impending doom.

[Iceberg]

IF only CO2 were being reduced, however last year they rose 5% higher than the highest ever as the world came out of recession, the world hasn't really taken notice yet.

http://www.bbc.co.uk/news/science-environment-13595174

I am sorry Jethro but I disagree with most of your statements AR 5 will be interesting when it finally comes out are you seriously saying that in AR4 there is no peer reviewed evidence for the IPCC views on cloud feedback ?, re the role of the Arctic there are many reasons why the Arctic is important in self regulation of the global climate IMO, the big question is how does this happen during the height of summer when the ice isn't there ?

What effects does this have on the amount of heat the sea absorbs, how much extra solar is not reflected back to the atmosphere ?, how much will this effect global temps ? What effects on ocean circulations. ?, and the really big of greenland which is starting to lose ice almost exponentially. ?

Then you've got effects on the Arctic Tundra of permafrost melt, methane release.

[jethro]

I didn't say emissions were not rising, I said measures are being taken to change the situation; countries the world over are looking at green energy. It won't happen over-night but it will happen so the future vision of endless rising emissions is an unfounded one - if nothing else, the dwindling stocks of fossil fuels will ensure this happens.

As I said, there is peer reviewed evidence for and against positive feedback from clouds; it's possible to pick and choose depending upon your viewpoint.

You are completely missing the fact that ice free water radiates heat away to space, this is a very important and often over-looked part of the equation. Thick sea ice is an effective insulator keeping the extra warmth in the ocean, hence most Arctic melt has been driven from below the surface - remove the surface and the heat can radiate away to space.

Arctic ice is not meant to be a static entity or in an ever increasing spiral of more and thicker ice - less ice is a symptom of a climate system working as it should. In the early decades of the 20th century there was a sharp decline in ice, estimates say there was more than today but the decline had been as sharp; the Arctic went from sharply declining to increasing ice levels in a few decades, reaching the pinnacle of extent in the 1960'/'70's that sparked fears of an impending ice age.

The ice waxes and wanes, it is a clearly visible illustration of the Earth's temperature, the mercury in the thermometer. Heat is transferred from the Tropics to the Arctic, whether that be atmospheric or ocean current makes no difference, it is a system working properly.

Measuring the workings of that system over short time periods merely captures a moment, that moment is not indicative of the future. Any possible visions of the future can only be vaguely judged by looking at past events, history shows the Arctic to be dynamic not static Judging the future of the Arctic on knowledge that we have contributed to the warming is IMO a misnomer, it doesn't matter where the extra heat has come from so long as the natural climate systems in place continue to work, there is no evidence to even suggest we have altered the climate system in the Arctic, it's merely working quicker than we have previously experienced and have data for. That is a system in fine working order, not one in a death spiral.

[Thundery wintry showers]

Here's the latest IPCC report's line on the water vapour feedback:

http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch8s8-6-3-1.html

I always have a couple of slight reservations regarding the use of climate models as the primary basis for making conclusions, one being that a climate model is limited by the assumptions that are built into it, and the other being that validating models by comparing them with observations implicitly assumes that climate variables will stay the same as the global temperature rises. However, when it comes to making predictions of future climate, the climate models are the best we currently have. The consistent signal that the scientists are getting from climate models is that relative humidity will most likely stay constant as global temperatures rise, meaning an increase in total moisture content of the atmosphere (the warmer the atmosphere, the more moisture it can hold) and a probable lagged positive feedback with water vapour due to extra radiative forcing.

I can see a significant amount of uncertainty in the magnitude of the feedback but note that uncertainty works both ways, therefore it could be smaller than most scientists currently think, or even non-existent, but then again it could be larger. The IPCC reports tend to side with what most scientists see as their current "best guess" at the situation.

[NorthNorfolkWeather]

Back to today. Is Nares 'Bridge' now 'failing down'?

The fact that it's still a question shows to me that you have been overegging this since the beginning of April. I think it's safe to say that we do expect it to go at some point this year, I believe it was 2009 was the first time the strait was traversed in June, so you seemed to be insinuating that the ice would fail within an unprecedented short period.

Do we have a history of when the ice bridge has broken over the last 30 to 50 years?

[Gray-Wolf]

The fact that it's still a question shows to me that you have been overegging this since the beginning of April. I think it's safe to say that we do expect it to go at some point this year, I believe it was 2009 was the first time the strait was traversed in June, so you seemed to be insinuating that the ice would fail within an unprecedented short period.

Do we have a history of when the ice bridge has broken over the last 30 to 50 years?

You're dead right NNW! I thought that this feature would be very short lived and fragile. Wrong! It appears to have been a strong structure which has been aided and abetted by low temps across the region since mid March?

There is a good commentary on the feature over the years here;

http://www.science20.com/chatter_box/arctic_tipping_points_4_broken_bridges_nares (plenty of thoughtful pieces and comments)

That said the inroads that open water in the NW Passage deep channel has made are seemingly well ahead of times? If we are seeing more volume of Pacific waters entering the Basin through Bering, and part of this water passes through the deep Channel to Baffin then last years 'losses' of shore bound, old ,fast ice have brought a larger volume available for warm water egress and so a more rapid melt in the areas of the channel that took a while to re-freeze last year due to the anomalous warm weather there (remember how long it took for Hudson to freeze up in 2010/11?).

Some folk are now thinking that the passage may well fully open by late June as the vast majority of ice in it is weak F.Y. ice?

The other area of interest is Beaufort. This area used to hold some of the Paleocrystic ice (S.Beaufort) that Prof Barbers team studied. We lost the last of that last year and so the area is now covered in ice less than 4 years old and a good deal thinner than last years ice. If this area opens up again we may well see a shift in the Arctic Amplification's impacts over early winter? The current understanding has H.P.'s forming over the heat shedding Barents/Kara seas (and the 'runoff of cold air plaguing us!) but if Beaufort is to act the same then we may get to a point where no significant cold pools form in the Basin until late Nov/Early Dec? How would that play out on the northern Hemispheres circulation patterns? (apart from starving it of potent Northerlies?)

It would impact ice thickness over the basin with only Dec/Jan/Feb and part of early March available for ice formation and it is such limited thickness that brought us here in the first place! To me this would be the logical way forward for the Arctic. Early melt out , long summer heat absorption, long period of heat loss prior to re-freeze.

The WAA we saw over Canada/Greenland last year would be squeezed into the lower latitudes (and be less modified?) if 'blocked' from the Arctic by a self propagating H.P. system driven by the heat loss of the oceans below.

And how would this impact the polar Vortex and ozone loss?

We may be on the verge of very interesting times!

[songster]

You are completely missing the fact that ice free water radiates heat away to space, this is a very important and often over-looked part of the equation. Thick sea ice is an effective insulator keeping the extra warmth in the ocean, hence most Arctic melt has been driven from below the surface - remove the surface and the heat can radiate away to space.

If I understand you correctly, you're saying that as the Arctic melts out, more open water will be exposed during the melt season, and that this will increase radiation back to space, thereby acting as a negative feedback and slowing the rate of melt.

If that is indeed what you meant (and I apologise if I've misread you), then you are overlooking the second law of thermodynamics. Heat cannot of itself pass from one body to a hotter body. Open surface water cannot radiate extra heat to space during the Arctic summer, when the Sun is up, and the sky is radiating heat downwards! Open water during the melt season will absorb more of the Sun's energy, speeding the melt. Open water after the equinox, when the Sun has set - that will indeed radiate to space: meaning the re-freeze will be faster. This is pretty simple stuff, and has been clearly observable for several years in succession now.

The fact that it's still a question shows to me that you have been overegging this since the beginning of April. I think it's safe to say that we do expect it to go at some point this year, I believe it was 2009 was the first time the strait was traversed in June, so you seemed to be insinuating that the ice would fail within an unprecedented short period.

You seem to be confused between Nares strait and the Northwest Passage. Nares is not important as a shipping route: the northern end is in the Lincoln sea, where the oldest and thickest ice resides. Anyone sailing through it (in the very rare occasions it's been possible) winds up in a lead along the northern shore of Ellesmere island, with nowhere to go subsequently except the pack ice. Nares is of interest due to ice loss through the channel when the bridges are broken. Extent-wise it's no great shakes: even in 2007 (if I recall correctly) it only exported around 10% as much as got exported through the much wider Fram strait. However, due to the positioning of the northern end of the strait, ice lost through Nares is disproportionately the older, more durable ice.

Do we have a history of when the ice bridge has broken over the last 30 to 50 years?

The last few years it's barely formed a bridge at all. Historically, it was rare for the strait to open at all, with an ice bridge remaining year-round. If it opened at all, it would be late summer (August-ish). The situation this year is of a newly-formed bridge after the Strait being open all last summer. I honestly don't think there's enough historical data to have the faintest idea how long such a bridge will last: whether it persists through the summer and restores the historical closed status of the strait, or whether it fails at some point and allows the ice to continue draining. For what it's worth, as of the 23rd of May, the Canadian ice service were still reporting it as thick first-year ice (> 1 metre).

This paper is likely of interest: http://www.agu.org/journals/gl/gl1003/2009GL041872/2009GL041872.pdf

Edited June 1, 2011 by songster