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Arctic Ice 2009/2010

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This is the new thread for the Autumn Winter Ice Recovery Phase.

This is the final spreadsheet showing the Summer Ice Position.

This is the first Autumnal update for the season and this will be updated regularly.

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This is the new thread for the Autumn Winter Ice Recovery Phase.

This is the final spreadsheet showing the Summer Ice Position.

This is the first Autumnal update for the season and this will be updated regularly.

Why is there such concern over the ice melt etc when it doesnt look as bad as the media and world governments think it is? Looking over the past 6 years it looks pretty average to me

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Why is there such concern over the ice melt etc when it doesnt look as bad as the media and world governments think it is? Looking over the past 6 years it looks pretty average to me

The problem is that the last six years are all remarkably low in relation to longer-term data.

post-8945-12544907140844_thumb.png

As seen at http://nsidc.org/arcticseaicenews/ the 2009 minimum is 24% below the long-term average, which is an awful lot of white shininess lost from the top of the world. Also, a lot of the more stable multi-year ice was lost in 2007. We can only hope that in future years the levels can recover, but you can see the long-term interannual trend in minima (to 2007) below...

{EDIT: Graph to 2007 removed - updated graph to 2009 posted by pottyprof below}

Figures from NSIDC.

sss

post-8945-12544910696494_thumb.jpg

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Well.. We can show a current NSIDC graph..

n_plot_hires.png

As with the 1998 temperature graph, there has to be a high point/low point and showing one that isn't current, doesn't give the whole picture. Agreed, the amount of ice is still on a downward trend but there is a glimmer of hope.

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cheers for providing the updated graph pottyprof - it is always relevant to provide the up-to-date data, and I didn't manage to find it. There's a wee glimmer of hope in the last two years' sea ice values, but I'll want to see a continued recovery and more multiyear ice before I'll start counting the swallows and declaring the season. Re 1998 temps - it's clear that 1998 was an outlier in the continued warming trend, as 1980/1981 and 1990, or as 1976 was a cooler outlier. The whole picture of temperatures is still an upward trend though...

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Just to point out that sunny starry skies is correct, the average of the past 6 years are well below the 30 years averages.

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Just to point out that sunny starry skies is correct, the average of the past 6 years are well below the 30 years averages.

Just out of curiosity - what is the past 6 years average if you discount 2007 ?

Also - Ice extent seems to be increasing faster now after the lull after the minimum was reached.

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http://in.reuters.co...E5916OP20091002

just found this.:doh:

its not good no freeze happening yet worring indeed.

This is talking about the older thicker multi year ice, which isn't shown in any of the two graphs just posted and along with the decline in extent over the last 5 years is a major issue in the Arctic.

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This is talking about the older thicker multi year ice, which isn't shown in any of the two graphs just posted and along with the decline in extent over the last 5 years is a major issue in the Arctic.

Yes the downward trend is a major issue, however both of the graphs I gave a link to combine both multi year and and first year ice. I don't think there are any graphs which just show multi year ice however this link gives us some idea of concentration / thickness - http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.color.000.png

After the record loss of 2007 if we were going to see any increase from that minimum (which we have) it would of had to of been first year ice anyhow, and now after a second year of improvement the ice will be even stronger.

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Sorry snow white, just to clear it up, neither of those graphs are any good at looking at multi year ice, multi year ice might be 0% or 100% on those graphs or anything in between.

The AMRSE data does give you an idea of concentration but concentration is again of no relavence of ice thickness. You might have a unbroken layer of ice 20 cm thick or broken up ice at 25% with a thickness of 2M.

The only problem is that since 2007 the thick older ice has been in rapid decline, (it was in decline before that as well).

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Sorry snow white, just to clear it up, neither of those graphs are any good at looking at multi year ice, multi year ice might be 0% or 100% on those graphs or anything in between.

The AMRSE data does give you an idea of concentration but concentration is again of no relavence of ice thickness. You might have a unbroken layer of ice 20 cm thick or broken up ice at 25% with a thickness of 2M.

The only problem is that since 2007 the thick older ice has been in rapid decline, (it was in decline before that as well).

Sorry I don't think you understand, I did not say the graphs were any good for looking at multi year ice, the graphs show sea ice extent / area which is all kinds of ice (1st year, 2nd year, 10th year etc).

If 'since 2007 the the thick older ice has been in rapid decline' why has there been an INCREASE in the minimum for the past two years ?

Am sorry Iceberg but your not making sense and I do not want to clog up the thread trying to get through to you !!!

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Snow white, your right I am very confused, but 2 posts isn't clogging up a thread and this is an important discussion on the state of the Arctic. People might well look at the extent see it improving and think that everything is OK.

If we take this back to the point I made.

A report on multi year ice by a sea-ice expert with the U.S. National Oceanic and Atmospheric Administration with many years of knowledge can be dismissed in your opinion and you posted up a graph to say that things are going reasonably well as opposed to what he's saying.

You then said that the graphs do show multi year ice and then finally said that the graphs are no good at looking at multi year ice and that I am just not getting what your saying, (If the graphs are no at looking at multi year ice, why mention them with an article on multi year ice saying take it with a pinch of salt)

Ice extent can increase, but ice thickness can go down as can the amount of older ice.(If the amount of first year ice is the ice that is growing.)

On the summer Arctic thread I posted images from NOAA/NSIDC which clearly showed the loss of older ice after the summers of 2007 and 2008, the 2009 data should be out in the next week or so. This data isn't perfect, but if we can't trust the people that fly over the ice in planes year on year examining the ice who can we trust ?.

I am not trying to be argumentative but I really don't get what your saying and why you want to dismiss the report mentioned.

I am happy to leave it here though as I agree that two people going backwards and forwards might be boring for people. :)

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On the summer Arctic thread I posted images from NOAA/NSIDC which clearly showed the loss of older ice after the summers of 2007 and 2008, the 2009 data should be out in the next week or so. This data isn't perfect, but if we can't trust the people that fly over the ice in planes year on year examining the ice who can we trust ?.

Certainly looking forward to that.

To be honest, this report doesn't really say anything that any we didn't know, the important thing which should come out is amount of multi year this year compared to recent years, and this isn't given any data at all.

There is a danger with articles like this in that they spin old data, when the data should be allowed to speak for itself.

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Here's a question. If the ice doesn't melt does it matter what age it is?

If the ice extent minimum continues to increase over the next couple of years the age of the ice will be relatively irrelevant except in terms of statistics. There was AFAIK more ice in the Beaufort Sea area than in the last two years despite the age of the ice.

What seems to be repeated continually is that as well as a record minimum in 2007, there is now significantly more single year ice. The latter information is totally superfluous.

If there is less ice than there has been there will always be more single year ice the next year. There's no point in stating this as extra evidence it's not it's a consequence of the previous year's ice melt not anything else.

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Michael, the difference between single year and multi year ice does matter for the reasons that the expert gave.

"The one-year ice that accounts for the increase over 2007 and 2008 -- pancake-flat pieces with finger-like surface ridges etched by movements of the water -- is no substitute for the thick multiyear ice, Overland said.

"It's thinner. It's more broken up. And it moves faster," he said. "And all of that contributes to melting earlier in the season."

We are saying that since 2007 there is more single ice, but we are also saying that there is less older ice (not just as a percentage), both myself and GW have been saying this for ages now, with this article we have an ice expert at NOAA saying it as well.

He is talking about a specific are in the Arctic and we certiantly can't extrapolate from this, but his comments about the lack of multi year ice are reinforced by his CURRENT observations from the coast guard plane.

I am not saying there is any earth shattering revelations, just that why can it be taken with a pinch of salt ?.

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With respect that does not answer my question, I know the difference between first year ice and older ice. If the first year ice does not melt in the melt seaosn it doesn't matter what age it is as next year it will be 2 year old ice etc.

If there is more ice at the minimum this year than last there is potentially more second year+ ice too. If not it suggests that that some of the first year ice from the previous year lastted better than some of the older ice. The bottom line is the minimum area/extent not the age. You could use one as the predictor of the other I guess but based on that the 2008 minimum would have been lower than 2007.

Yes, perhaps it's an indicator but it's significantly outweighed by weather conditions as the last 2 years demonstrate.

I've not mentioned taking things with a pinch of salt and I don't especially question the experts' opinion but the data in terms of the last 2 years' minima v the one year ice (i.e. an increase of the former and a increase in the latter) suggest it's not exactly an inversely proportional relational and that other factors may be more dominant.

So ice age is an interesting factor but not the over-riding one and the amounts of single year ice should be reasonably easy to predict based on the extent and location of ice melt combined with the movement from the preceeding season. Not rocket science and not another factor in a downward spiral, just another symptom of the last few years.

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I completely disagree Michael, Many experts suggest that the reason we have the mass melt in 2007 is that the older ice had been steadily eroded before that date to allow the ice no protection when a good melt year came along.

The age of the ice is sensibly looked at after the summer season as it shows how much older ice is left. Potentially is the important word there there might be there might not be .

The age of the ice is an important indicator as to the fragility of the ice, a Recovery of ice extent without a recovery of older ice can be swept away by a good melt year. This is why it's important.

Of course synoptics are very very important, but I wouldn't want to rely soley on synoptics to improve the ice over the next few years.

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I completely disagree Michael, Many experts suggest that the reason we have the mass melt in 2007 is that the older ice had been steadily eroded before that date to allow the ice no protection when a good melt year came along.

The age of the ice is sensibly looked at after the summer season as it shows how much older ice is left. Potentially is the important word there there might be there might not be .

The age of the ice is an important indicator as to the fragility of the ice, a Recovery of ice extent without a recovery of older ice can be swept away by a good melt year. This is why it's important.

Of course synoptics are very very important, but I wouldn't want to rely soley on synoptics to improve the ice over the next few years.

I agree with Michael - the last few years have demonstrated that synoptics are the key. Wind and pressure patterns in 2007 were very unsual - in the timing and duration of the anticylonic spell and higher upper temperatures over the arctic - history would indicate they will most likely not happen again for some time - and it's probable IMO that the shift in ocean cycles in the pacific played some role in what happened - with the pacific moving from it's warm to cold phase, the excess energy had to be released somewhere.

Each year since 07 (well okay there's only been 2) - we've had various headlines forecasting a new record low - and it simply hasn't happened - kind of like the chap with the 'end of the world is nigh' placard.

If the AMO is now switching colder over the next 5 years, then the ice will start to increase - as extent in the Barents area (which has been one of the notable reduction areas in recent years) will recover.

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I completely disagree Michael, Many experts suggest that the reason we have the mass melt in 2007 is that the older ice had been steadily eroded before that date to allow the ice no protection when a good melt year came along.

The age of the ice is sensibly looked at after the summer season as it shows how much older ice is left. Potentially is the important word there there might be there might not be .

The age of the ice is an important indicator as to the fragility of the ice, a Recovery of ice extent without a recovery of older ice can be swept away by a good melt year. This is why it's important.

Of course synoptics are very very important, but I wouldn't want to rely soley on synoptics to improve the ice over the next few years.

I feel like I'm bashing myhead off a brick wall at the moment.

If the first year ice does not melt in the melt season it doesn't matter what age it is. I'm not suggesting as you imply that the ice age is of no significance, I'm suggesting that if like in the last 2 years it does not melt it suggests it is not the only or even most important factor, although it can play a significant role. That's all, nothing more nothing less.

Put simply:

The ice age is symptomatic of what has happened not necessarily what will happen.

Disagree if you wish, but I'm not saying it a fourth time. :)

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Certainly looking forward to that.

To be honest, this report doesn't really say anything that any we didn't know, the important thing which should come out is amount of multi year this year compared to recent years, and this isn't given any data at all.

There is a danger with articles like this in that they spin old data, when the data should be allowed to speak for itself.

i agree.

it makes you wonder sometimes that stories like this are trying to push the worst cases onto the public even though theres been a couple of years recovery.

i think it would be silly to underestimate a recovery up to a normal rates in the coming years,

because we really dont know whats happening,

is it just that less focus on the recovery and more spin on the melt.

thats where it all becomes messy.

multi year ice is ofcoarse 3 years of untouched ice,

so then if next year there was more ice like 40% recovery then that would be due to multi year ice,

so then next winter will be crunch time.

but its starting get a little confusing the reason i think is because 2007 was such a big issue up there,

stories that where realesed saying this 2007 style melt would happen every year,

but i has not happened so what if next year shows another recovery?

i think 2007 was a freak event maybe like our winter last year who knows.

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Ice age matters a lot for a number of reasons. The most important is obviously it's ability to over summer even in unfavourable conditions. Mark Serreze has said as much each address he gives (head of NSIDC). He is quick to point out the turnround ,over the past 15yrs, of the proportions of multiyear and younger ice (perennial was once the majority ice type now it is 10%). The ICESAT mission also shows that basal melting over winter and summer means that 'new' perennial never reaches the dimensions of the old perennial so any comparison of ice types today ought to recognise this change (surely?). Old perennial used to act in a way similar to glacial ice with physical changes occurring as it aged. The changes meant it became more durable with age but these 'changes' were part driven by it's depth.With the loss of perennial 'depth' we also loose the ice's tenacity to endure.

In 05? a buoy was dropped in the Siberian side of the Arctic.It emerged on the Svalbard side 2 years later. They repeated this in 07 and it took 7 months to do the same trip. I'm sure the transport of the 'pole' equipment (dropped each year) would provide a similar view of how much quicker ice travels these days on the Arctic Gyre and associated currents. How can ice endure in such conditions? We are still in the process of 'flushing out' the last 10% of the 'old' perennial today (hence the NW passage being 'clogged up this summer) and any opportunity to scan the east coast of Greenland will show these big bits of perennial as they move out into the north Atlantic (I remember someone mooting Greenland and Iceland nearly being 'joined ' by an ice bridge in Oct/Nov last year only to fins a flotilla of old perennial on it's way south.

So, we have thin ice predominating, we have basal melt 12 months of the year, we have ocean currents running faster than ever recorded flushing ice out at the peripheries, we have three year old ice no thicker than the average single year (at winters end). Should I be as concerned as the experts that one 'perfect storm' will take us well below 07's exceptional losses?

None of this is welcome, none of this is pleasing. Those of us with concerns are on a hiding to nothing.We cannot feel in any way rewarded when we see our understandings confirmed (unlike the cockle-doodle-doing we get when we have a high ice extent at winters end or are up on the appalling 07' extent in autumn). We listen to the experts ,understand what they tell us ,study the reports/papers and find ourselves accepting that as long as nothing alters within the system as it is we will live to see an ice free Arctic ocean.

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3 points here, the flushing away of old ice is important.

The importance of old ice is obvious, but the experts are over egging this as in the past 2 summers, the experts have underestimated the ice retention. There are many sources which have shown they expect the 2009 ice extent to be around 2008 or slightly above, Very few expected ice retention to be above 5m.

However until we get the actual split of ice for 2009, we cannot really make any definitive comments. I also wonder why there is such a lack of information in this regard surely this should be more freely available.

2007 had a terrible impact on old multi year ice, however if we continue with the year on year increase in ice extent, then there is also likely to be a corresponding increase in the level of multi year ice, however there may be a timing lag in relation, perhaps with particular regard to old multi year ice.

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