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Arctic Sea Ice Discussion 2016-2017: The Refreeze.

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It's a near Hemispheric feedback if you look how far outside the Arctic the cold has flowed this year and the impacts this has brought?

We might be zoned in on the air masses pushing the cold from the Basin but we should be mindful of the other side of the coin too!

There is more of a chance of problems occurring in the lower Lats where cold can run into really warm air and far more people live!!!

This is the second winter of near constant WAA into one area of the basin or another! DMI80N is set orbital again on the plot and the spring 'warm up' starts to look real close......

It is almost as if ,from October onward, there has only been 2 cells in the hemisphere? a tropical ( Hadley?) cell and the other two all mixed ( or in the process of mixing)  into one.......

Edited by Gray-Wolf

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Some recent extent increases pleasing to see.

VISHOP_Extent.png

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Until you look sat what is occurring and then not so much stew!

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The PIOMAS update for ice volume this week is an eye-opener for sure:

http://neven1.typepad.com/blog/piomas/

We're about 1500km3 below the next lowest and 2500km3 below this point last year. The current volume is equal to the 1979-2016 mean in early-July!

If we were the same amount below the previous lowest in September then we'd have a mere 2000km3 of ice remaining in total.

If we get a warm spring and summer up there (and we look like transitioning to a weak El Nino at the moment), then we'll be reaching new lows this year.

Edited by reef

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4 hours ago, reef said:

The PIOMAS update for ice volume this week is an eye-opener for sure:

http://neven1.typepad.com/blog/piomas/

We're about 1500km3 below the next lowest and 2500km3 below this point last year. The current volume is equal to the 1979-2016 mean in early-July!

If we were the same amount below the previous lowest in September then we'd have a mere 2000km3 of ice remaining in total.

If we get a warm spring and summer up there (and we look like transitioning to a weak El Nino at the moment), then we'll be reaching new lows this year.

Not looking good, is it!

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Well we have seen the current storm drive a stall in sea ice numbers over the past week and watched all the snow melt out on the various Svalbard Web cams as temps there stayed above freezing, and not the minus 17 they should currently be! That is another loss of potential Freezing Degree Days ( FDD's) dropping us even further away from the total FDD's we should be sitting at. FDD's are like a measure of the energy you will need to melt out that ice so FDD's at 2/3rds of what they should be will mean it takes only 2/3 rds the energy to melt as it would if FDD's were normal. We saw this last year with a cold cloudy 'high season' still able to melt out enough ice to drop us to 2007 levels. This year is far worse than 2016 at this point across all measures ( area/extent/Volume/FDD's) so we know that even if we have as rubbish a summer over the basin this year we'll still see ice levels drop below last year so secure at least second lowest. Any positive melt forcings over summer could see us crash into a new record low. A return of the perfect melt storm ( which is now within its time frame) will mean laying in supplies for the food riots to come! (lol)

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On 11/02/2017 at 10:58, Gray-Wolf said:

Well we have seen the current storm drive a stall in sea ice numbers over the past week and watched all the snow melt out on the various Svalbard Web cams as temps there stayed above freezing, and not the minus 17 they should currently be! That is another loss of potential Freezing Degree Days ( FDD's) dropping us even further away from the total FDD's we should be sitting at. FDD's are like a measure of the energy you will need to melt out that ice so FDD's at 2/3rds of what they should be will mean it takes only 2/3 rds the energy to melt as it would if FDD's were normal. We saw this last year with a cold cloudy 'high season' still able to melt out enough ice to drop us to 2007 levels. This year is far worse than 2016 at this point across all measures ( area/extent/Volume/FDD's) so we know that even if we have as rubbish a summer over the basin this year we'll still see ice levels drop below last year so secure at least second lowest. Any positive melt forcings over summer could see us crash into a new record low. A return of the perfect melt storm ( which is now within its time frame) will mean laying in supplies for the food riots to come! (lol)

Although I don't dispute the first part of what your saying, I do however have some qualms with the 2nd part because we all know the behaviour of sea ice won't behave as simple as that. Last year was quite cool across the summer but I do think conditions we had in May had some sort of impact like the large opening we saw in Beaufort and the amount of warmth that entered the basin quite frequently during May. Also, towards the latter part of August and start of September did have very favourable conditions for ice melt with the strongest dipole I think I have seen, fortunately that set up occured at that point instead of June!

I still believe weather ultimately plays a big part but I do admit with the ice becoming more thinner then weather will play less of a role. If the HYCOM thicknesses maps are anything to go by, then its quite an alarming situation we are seeing across the Chuckchi and Laptev seas with ice really quite thin and in general much thinner than last year. Hopefully the current strong PV can help the ice somewhat but it does feel a little bit a case of too little too late.

Edited by Geordiesnow

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The coastal open water in Beaufort was open by the time the sun got to work and destroyed a lot of ice that drifted that way over summer?

This is the point though, the weather did not stop the ice melting. Over similar type synoptics since 07' ice loss has always been stopped when cool,cloudy conditions dominated across the basin.

We are in far worse state at this point than we were this time last year so what are supposed to think about what we will see across the melt season?

Do we dare to think that an even worse pack will do better ( keep more ice) than last year?

 

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11 hours ago, Gray-Wolf said:

The coastal open water in Beaufort was open by the time the sun got to work and destroyed a lot of ice that drifted that way over summer?

This is the point though, the weather did not stop the ice melting. Over similar type synoptics since 07' ice loss has always been stopped when cool,cloudy conditions dominated across the basin.

We are in far worse state at this point than we were this time last year so what are supposed to think about what we will see across the melt season?

Do we dare to think that an even worse pack will do better ( keep more ice) than last year?

 

Hi,

I think conditions for the next 7 days or so look quite favorable to sea ice growth up there. I wouldn't be surprised to see that in the next 2 weeks that sea ice has been where it usually is for the time of year (as per the last decade). 

Now, to the other comment, no. I don't think there is too much relation as to the starting point in Spring as to what happens by September. If you look at 2012, sea ice started relatively well, but then dipped to a low. Where as 2010 started similarly, but didn't manage to get to the 2012 level.

This shows that what happens in Spring and Summer is more important than what you start off at the end of Winter. Of course, it is all within reason. There could be terrible conditions for sea ice for the next two months and it may indeed start off so low, that a low in summer is unavoidable, but it would take something spectacular.

Screen Shot 2017-02-16 at 10.44.44.png

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I think this move to a more pronounced 'winter conditioning' began in 2013 with the first of the basin wide 'crackopalypse' events? Continued fragmentation events made sure that the whole basin ended up a collection of small floes glued together with new ice. This helped with last years early withdrawal of ice across Beaufort and the evolution of the ice melt zone to the west of Beaufort and up into ESS. With this uptick/evolution of a warm moist air masses into the basin throughout winter we are seeing a pack poorly tempered to deal with summer no matter the weather ( it will always go above freezing temp for Sea water in the basin over summer!) .The logical conclusion would be a seasonal pack with the basin ice similar in nature to the ice we see in Hudson ( late formed and not tempered by full Arctic basin cold temps?).

We saw the type of summer that brought us last years second lowest numbers and we've seen a winter now that has failed to give us a similar volume to last year and has been far warmer over the season than last year so just what would you expect the qualities of this ice are? Will it fayre better over a 2016 summer or worse?

 

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On 16.02.2017 at 12:23, Gray-Wolf said:

I think this move to a more pronounced 'winter conditioning' began in 2013 with the first of the basin wide 'crackopalypse' events? Continued fragmentation events made sure that the whole basin ended up a collection of small floes glued together with new ice. This helped with last years early withdrawal of ice across Beaufort and the evolution of the ice melt zone to the west of Beaufort and up into ESS. With this uptick/evolution of a warm moist air masses into the basin throughout winter we are seeing a pack poorly tempered to deal with summer no matter the weather ( it will always go above freezing temp for Sea water in the basin over summer!) .The logical conclusion would be a seasonal pack with the basin ice similar in nature to the ice we see in Hudson ( late formed and not tempered by full Arctic basin cold temps?).

We saw the type of summer that brought us last years second lowest numbers and we've seen a winter now that has failed to give us a similar volume to last year and has been far warmer over the season than last year so just what would you expect the qualities of this ice are? Will it fayre better over a 2016 summer or worse?

 

No idea, to be perfectly honest. The only thing I can say from looking at the past decade is that the conditions at the end of a growing season for ice have not reflected the Spring and Summer melts. Therefore you could argue that continuing to look for a link that the data says doesn't exist is a little insane. Of course, a stopped clock is right twice a day, so at some point a slow ice growth rate in winter may indeed lead to a record low in summer. When that happens (most likely when, not if), it would be hard to then say what the cause was. Was it because of the starting point? What happened in the melt seasons? Combination of both? 

I think we also need to be careful in assuming that because ice melted in Spring or didn't grow in Autumn or Winter as much as usually, that this will inevitably lead to a record low in Summer, as it is too simple to assume that different ice will be melted because the other ice isn't there.

It's actually quite fascinating to watch, though. This seasons sea ice growth has been like no other. It will be very interesting to see what we get to at the end of March, what happens over the melt season and then what happens in the grow season again.

The Antarctic as well. Managed to hit a low of -0.13% (or 1k square miles) lower than recorded in 97 (i think 97, can't remember and too lazy to look it up). That's off the back of records highs in previous years. A new trend, or an anomaly? Where will it get to in the Southern Hemisphere winter? We won't need to wait long to find out, as the grow season starts again very soon.

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But, and this is the thing jvenge, this is not the same ice as we had in 07 or half of the decade you speak of?

In 07' we still had reserves of thick ,paleocryistic ice in floes hundresa of km across, we had over 2m ice over much of the pack and  the Central Arctic Basin was one big sheet of ice with the rare lead in it from time to time. The ice had sat under a cold dome all winter curing at up minus 45c for up to 5 months.....

What do we have out there in the basin now, only ten years later?

We have lots and lots of First Year ( FY) ice that has been under far warmer winter conditions than we have ever measured up there.

The  'older ice' is mainly below 2.5m in thickness having failed to thicken due to 1/ snow cover insulation from the WACCy snow events in October ( which may also be giving Cryosat2 problems with its free board calcs?) 2/ warmest arctic winter ever recorded not providing it the cold it used to see?

What I'm trying to say is I think you are not 'witnessing' the same degradation and changes in the behaviours of the pack, over the past decade, that I seem to be seeing?

I'm not singling you out in particular as I honestly believe their are millions of folk who do not fully appreciate just how rapid , and disfiguring, the changes to the Arctic have been since the 07' crash?

It's almost as if they think its the same ice is up there still doing battle with summer each year whereas there is no ice from then in the Basin any more?,

You'd be pushing it to find significant 5 year ice that was not 'rotten ice' ,and so a conglomeration of a 5 year old top surface with a progressively younger 'keel' glue on below and that will behave very differently to 5 yr ice ten years ago?

The floe sizes have radically altered since 07' , if you looked at a rough average the sizes back in 08' ( or did a quick look through sat images of the different years?) you would see that we have reduced floes sizes as the ice has become younger, thinner and weaker over the period since 07'  ?   

Now we have a pack that by mid melt season is now seeing 'side melt' to flows becoming ever more important and speeding up the way the floe melts out ( think the speed crushed ice melts compared to the same mas in ice cubes due to the percentage of exposure of skin to mass?) , Apparently when a floe goes below a 100m diameter the side melt causes more loss than top/bottom melt so the smaller the floe the quicker they go! This is what the new 'pancake ice' and 'crackopalypse' events, post 2013 have brought us!

And now this past two winters of show us just how 'altered' the atmosphere has become and just how powerful it is as a 'heat engine' under these new forcings.

Ice denatured the way it has been these last 5 years and it will melt out more readily ,no matter the weather, and ice that is no longer 'Arctic cold' will melt faster also.

I'd say we do not need to see any long periods of high melt forcings over the coming season lest we see an unstoppable chain of events beginning!

 

 

Edited by Gray-Wolf

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16 minutes ago, Gray-Wolf said:

But, and this is the thing jvenge, this is not the same ice as we had in 07 or half of the decade you speak of?

In 07' we still had reserves of thick ,paleocryistic ice in floes hundresa of km across, we had over 2m ice over much of the pack and  the Central Arctic Basin was one big sheet of ice with the rare lead in it from time to time. The ice had sat under a cold dome all winter curing at up minus 45c for up to 5 months.....

What do we have out there in the basin now, only ten years later?

We have lots and lots of First Year ( FY) ice that has been under far warmer winter conditions than we have ever measured up there.

The  'older ice' is mainly below 2.5m in thickness having failed to thicken due to 1/ snow cover insulation from the WACCy snow events in October ( which may also be giving Cryosat2 problems with its free board calcs?) 2/ warmest arctic winter ever recorded not providing it the cold it used to see?

What I'm trying to say is I think you are not 'witnessing' the same degradation and changes in the behaviours of the pack, over the past decade, that I seem to be seeing?

I'm not singling you out in particular as I honestly believe their are millions of folk who do not fully appreciate just how rapid , and disfiguring, the changes to the Arctic have been since the 07' crash?

It's almost as if they think its the same ice is up there still doing battle with summer each year whereas there is no ice from then in the Basin any more?,

You'd be pushing it to find significant 5 year ice that was not 'rotten ice' ,and so a conglomeration of a 5 year old top surface with a progressively younger 'keel' glue on below and that will behave very differently to 5 yr ice ten years ago?

The floe sizes have radically altered since 07' , if you looked at a rough average the sizes back in 08' ( or did a quick look through sat images of the different years?) you would see that we have reduced floes sizes as the ice has become younger, thinner and weaker over the period since 07'  ?   

Now we have a pack that by mid melt season is now seeing 'side melt' to flows becoming ever more important and speeding up the way the floe melts out ( think the speed crushed ice melts compared to the same mas in ice cubes due to the percentage of exposure of skin to mass?) , Apparently when a floe goes below a 100m diameter the side melt causes more loss than top/bottom melt so the smaller the floe the quicker they go! This is what the new 'pancake ice' and 'crackopalypse' events, post 2013 have brought us!

And now this past two winters of show us just how 'altered' the atmosphere has become and just how powerful it is as a 'heat engine' under these new forcings.

Ice denatured the way it has been these last 5 years and it will melt out more readily ,no matter the weather, and ice that is no longer 'Arctic cold' will melt faster also.

I'd say we do not need to see any long periods of high melt forcings over the coming season lest we see an unstoppable chain of events beginning!

 

 

I'm in my phone now, so sadly can't research and post graphs. However, we can hit a few things back and fourth. Find a sea ice extent graph showing all years from 2007. Let's look at what the data shows. Let's have a look at the trend year on year since 2007. Let's look at seasonal highs and how the low that year corresponded. I showed one above showing recent years and i didn't see a relation between high and low points, but maybe you do.

 

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meanT_2017.png

Yup Summer Sun DMI 80N is closer to the 'average line' than it has since summer when latent heat of fusion had it pegged to the 'average'. With the sun on the rise is surely is too little too late?

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3 hours ago, Summer Sun said:

 

But that in itself is a nonsense Tweet. One would think sea ice is far away from where it usually is. It's not.

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2 hours ago, Gray-Wolf said:

meanT_2017.png

Yup Summer Sun DMI 80N is closer to the 'average line' than it has since summer when latent heat of fusion had it pegged to the 'average'. With the sun on the rise is surely is too little too late?

Is it? See attached.

I didn't bother to check the forecast up there for the next 10 days yet :-) Lazy, I know, but if the tweet is correct, then surely that just means the extent will be where it has been for the past decade.

Captură de ecran din 2017.02.21 la 14.56.33.png

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25 minutes ago, jvenge said:

But that in itself is a nonsense Tweet. One would think sea ice is far away from where it usually is. It's not.

It is far away from where it usually is, last year was not usual either.

zzZbcng.png FullSize_CICE_combine_thick_SM_EN_201702

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Just now, BornFromTheVoid said:

It is far away from where it usually is, last year was not usual either.

zzZbcng.png FullSize_CICE_combine_thick_SM_EN_201702

Quite happy with the one I previously posted, showing the most recent years. I think in your own recent update you mentioned it is now the second lowest on record as well, yes?

So speaking honestly, where do you expect see ice to be at the end of March?

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Just now, jvenge said:

Quite happy with the one I previously posted, showing the most recent years. I think in your own recent update you mentioned it is now the second lowest on record as well, yes?

So speaking honestly, where do you expect see ice to be at the end of March?

Normal would be close to the long term average. Last year was way below the long term average, so a graph showing us a little above last year doesn't show that we're close to normal.

As for the end of March, you might as well be asking me to predict the weather for the Arctic over the next 5 weeks! However, I wouldn't expect it to get close to the long term average.

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Just now, BornFromTheVoid said:

Normal would be close to the long term average. Last year was way below the long term average, so a graph showing us a little above last year doesn't show that we're close to normal.

As for the end of March, you might as well be asking me to predict the weather for the Arctic over the next 5 weeks! However, I wouldn't expect it to get close to the long term average.

Haha, fair comment. Yes, indeed, it is tricky. I'll stick my neck out and say it will be similar to 2014. Play along :-)

 

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Given the extraordinarily poor integrity of the ice (not captured by sea ice extent measures), I expect it would take a cool, cloudy/foggy sort of spring like I believe 2013 had in order to bring 2017 on a par with 2008-2011 for example. A 'regular' spring of weather would keep 2017 close to or a little below the currently record-low values of 2016, while a spring similar to that of last year would leave the ice in a state of degradation some way beyond anything ever witnessed on approach to the summer solstice.

I am concerned that given the poor structure to a lot of the ice, even a relatively short spell of exceptional warmth in the early-mid spring could open up enough leads to greatly increase the proportion of solar input being taken up by the oceans during the following peak solar months during clearer periods. Given the scale of the difference in energy transfer between ice and water surfaces, it would take a lot of cloud to prevent a net increase in heat uptake... but I daresay last year came close, with the spring uptake perhaps proving the more significant for how the autumn panned out in terms of ice extent and quality. So it's possible that the increased moisture flux provides a negative feedback that buys the Arctic a bit more time... but I wonder if tropical forcing could still override that and produce a sunny summer month at some point akin to July 2015? I sense that we are one such summer month (perhaps May at a long stretch) away from sea ice being sent into freefall. Even if that doesn't happen we have the impact of strong storms, benefiting from the increased heat and moisture availability, to worry about - another reason why the integrity of the ice is so important.

 

The current colder weather across a large part of the Arctic is looking unfortunately short-lived, but welcome nonetheless. The 7-16 day period is looking uncertain with signs that the jet will trend south but with low heights tending to remain in the Canada-Greenland area which threatens to set up a long-fetch southwest flow from the Atlantic side should high pressure develop over Scandinavia as per some recent model runs. On the other hand, the mild air might just sail right on through Europe, underneath a wedge of higher heights, while on the Pacific side there seems not to be much of a poleward heat flux threat on the cards, and there are signs that a block over East Asia could lift some deep cold out of Central Asia and send it across the Arctic, which would be a nice booster for the sea ice.

So as yet I can't see any reason to anticipate things leaning one way or the other with respect to the scenarios I outlined at the start of this post. There remains reasons to be hopeful and that'll do me for now :)

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