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Arctic Sea Ice Discussion 2017 - The Melt Season


Gray-Wolf

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Posted
  • Location: Morecambe
  • Location: Morecambe
On 16/06/2017 at 22:09, knocker said:

The gfs and ecm still looking to develop quite a deep low for next weekend

ecm_mslp_arctic_9.thumb.png.5926cf0a6ed852693e212fcebb2a00e2.pnggfs_mslp_plev_arctic_33.thumb.png.a820c280c5de3285f05d5ce748c8ad87.png

The potential is certainly there as a cold low starts to mix in with a heat dome that is forecast over Siberia, these temperature contrasts certainly have the potential to produce a deep depression but even if it doen not rapidly deepen then all the models are trending a strong dipole like formation in the Chuckchi sea with pressure being high over Beaufort and much lower over Laptev, how long that lasts for is another matter but very strong winds will no doubt push that ice edge further Northwards yet again.

So potentially some interesting times ahead and even in the here and now, it will be interesting what this fairly deep low will do to the ice right now, is the air cold enough and the low not too deep enough not to cause damage to the ice or not?

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Posted
  • Location: Napton on the Hill Warwickshire 500ft
  • Weather Preferences: Snow and heatwave
  • Location: Napton on the Hill Warwickshire 500ft

The ijis link seems to be broken again ? anyone have a new link ? This one not working

https://ads.nipr.ac.jp/vishop/#/extent

 

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Posted
  • Location: Ireland, probably South Tipperary
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Ireland, probably South Tipperary
2 hours ago, stewfox said:

The ijis link seems to be broken again ? anyone have a new link ? This one not working

https://ads.nipr.ac.jp/vishop/#/extent

 

 

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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

As much-maligned as the extent metric is, it's going to be interesting to see whether the predicted return of the Beaufort High and with above average airmass temperatures affecting large parts of the Arctic, starting a few days from now, will manage to send 2017 into uncharted territory for July.

It's a relief that the deep low didn't reach the ferocious intensity that was once predicted, but it was still only a few hPa off the June record low pressure, and in combination with a vigorous secondary low over the ESS seems to have managed to draw a deep wedge of relatively warm and moist air across the Pacific side of the Arctic, which has triggered the onset of a lot of melt ponds in a short space of time.

0_mslp850_arc.png?cb=565 

Melt ponds cropping up so widely just ahead of a strong Beaufort High arriving is not a good combination at all for ice integrity and duration, but the 12z ECM does at least offer some suggestion that it may not remain strong for long, or even manage to sustain an Arctic Dipole for more than a few days;

48_mslp500_arc.png?cb=565 120_mslp500_arc.png?cb=565 216_mslp500_arc.png?cb=565

In fact there are increasingly strong hints of a Scandinavian blocking pattern emerging in early July. This could see the main brunt of attack being borne by the Atlantic side, where unusually cool and cloudy weather has allowed a large lobe of sea ice to persist longer than has been the case since at least 2006 (I think - maybe only 2011?). This side can be attacked much more directly by warm air off the N. Atlantic, as well as undermined by the oceanic currents, so the ice lobe could disappear very rapidly if such a pattern change unfolds.

240_mslp850_arc.png?cb=565 240_mslp500_arc.png?cb=565

Come to think of it, ECM manages a 'worst of both worlds' solution on this particular run, as a fairly strong and 'warm' high becomes centred over the Pacific side at the same time as the Scandi blocking emerges.This model really seems to have it in for the Arctic this year!

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

HI Knocks! I worry about the quality of the ice this year compared to all other years? It did not see the type of winter 'cold cycle' that other winters provide and this was compounded in areas by a deep snow cover from the succession of lows running up into our side of the basin?

If we had two 1m cubes of ice , one with an inner core temp of -25 and one of -20 would melt out times vary?

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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

It's fascinating how this year sees the vast majority of the volume situated on the Atlantic side of the Arctic, in stark contrast to recent years including, most notably, 2012.

In theory that means there's a lot more ice in a position exposed to oceanic melt-forcing that typically melts out all of the ice subjected to it by the minimum.

On the other hand, this year so far has displayed an impressive ability to keep the region much cooler than usual. So perhaps it will be an atmosphere v. ocean battle. Unfortunately water has vastly more heat capacity than air and the sub-surface heat reserves are relatively large even where surface temps are not that far above the long-term average. Any deep storms that cross the area such as we saw in late winter and early spring will cause some big problems.

According to predictive models working from the current situation, only an extreme retention-favourable Jul-Aug such as 2014 can prevent a record minimum in terms of sea ice extent this year.

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Posted
  • Location: Morecambe
  • Location: Morecambe

Interesting melt season thus far I got to say, ice extent across the pacific side looks very similar to 2007 but the CAB compared to 2016 from my observations looks more concentrated this year compared to last year and last year did see open water entering not too far away from the pole and a heavily fragmented CAB so there is maybe a case that this year we may even finish above 2016 despite so far weather conditions in general has been a bit more favourable for ice melt?

Looking ahead, it does look like high pressure will dominate the Pacific side and there are hints we may see a ridge entering from the Pacific to join up with the high in the Arctic which will cause strong southerly winds and bring in a lot of warm air again. As ever, its not always that plain sailing as this afternoon's GFS 12Z run shows which would be more favourable for the ice.

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

Hi G.s.! I'm not sure thast the more favourable weather is as impacting as it was even 5 years back? The fragility of the pack allows swells to mix up warmer waters from below bringing melt to the base even if surface melt is curtailed? Open water areas obviously warm and this water can then flow through the Trans Arctic drift and under the ice on our side of the basin even if our side is sealed?

By months end we should have a better handle on what is occurring as the sub 1.5m ice will be gone over most of the basin. this open water will then be studded with the slightly thicker floes but will the open water prove too much for most of that? The lack of deep cold over winter may also show impact in ice melt out rates? Will warmer ice need as much energy to melt out?

It is a scary period ( for me) as it will either confirm my fears or save us from them!!!

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Posted
  • Location: Morecambe
  • Location: Morecambe

Well last year shown quite nicely how on paper more favourable looking set ups still made us 2nd lowest on record but traditionally reverse di-poles would tend to favour retaining ice and its something I rather see than a true dipole at this time of year.

I'm not too sure about this "warm ice" and "cold ice" theory but the ice is thinner this year and for me its ice thickness that will no doubt play a major role on where we will end up by the end of this melt season. The pacific side of the Arctic has been melting quite rapidly this year which is no surprise as weather patterns have favoured this but it has not exactly been a 2007/2011 style set up either where high pressure and warmth were quite dominant in those melt seasons.

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

For ice to 'grow' over winter the cold needs to reach down through the ice to expand the floe down into the ocean. Put a warm blanket of snow over that surface and you insulate it from the cold above so no growth occurs? It is the same issue with the land that caught the WACCy snow? It might have taken longer to melt away but the land below was then ready to continue with its degradation as it was not placed in deep freeze over the winter. The explosion of the hillock on the june 28th might highlight this?

Apparently I mis spoke in claiming there were 700 more hillocks under investigation, apparently it is 7,000 more hillocks spotted and being monitored! It sounds very much like the 'blossoming' of the chimneys under the ESS earlier this decade ( which now see melt temps most of the year?).

As for 'thin ice' ? Well we have seen the old 07' record approached/matched by pretty average melt seasons just because the amount of FY ice as a proportion of the pack has grown so 'average melt seasons take it. this year we have the thinnest ice measured so surely even a slow year will see this ice melt? Late July/early Aug might be when we see this melt out occurring?

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Posted
  • Location: Morecambe
  • Location: Morecambe
12 hours ago, Gray-Wolf said:

As for 'thin ice' ? Well we have seen the old 07' record approached/matched by pretty average melt seasons just because the amount of FY ice as a proportion of the pack has grown so 'average melt seasons take it. this year we have the thinnest ice measured so surely even a slow year will see this ice melt? Late July/early Aug might be when we see this melt out occurring?

Well this thin ice towards the Pacific side of the Arctic will have an interesting 72 hours or so as we get a very warm plume heading in from the Pacific coupled with no doubt quite sunny skies to boot, we saw in 2015(around this time of year) the dramatic effects this had on the ice although thankfully it is not quite as severe and long lasting as it was back then as the pattern is forecast to break down quickly by low pressure over the CAB although the models kind of disagree on what happens next, most GFS runs had the low deepening but not one Euro run has backed this and some sort of reverse dipole looks the most likely and it will be interesting to observe what happens to the ice edge over Barents if the forecast Southerlies come to fruition as it looks a fairly potent southerly in store.

I think its fair to say whilst things do seem to be on a knife edge, we could be looking at a far worse situation when we saw those volume figures back in Spring and it is interesting what the final shape and extent of the ice will be come September.

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Posted
  • Location: Morecambe
  • Location: Morecambe

Well the 3 days of substantial of very warm air hitting the Pacific side of the Arctic is more or less over now as the reverse dipole takes shape but not without causing quite a lot of ice melt over the East Siberian/Chuckchi seas and the net result has been 3 consecutive century breaks in a row - not terribly unusual for July but goes to show, any real heat hitting this ice pack is causing substantial ice melt.

With the reverse dipole kicking in now and the weather forecast seem to be suggesting a fairly slack looking set up coming, extent figures could start to slow down somewhat, looks similar to the 2nd half of July 2014 but as it stands, not as cold in terms of upper air temps at least but if the favourable set ups last a good while then the ice pack has got a chance of not ending up too low but we shall see.

One thing to note is the definate trend of the Kara sea having a long heatwave which is already ramping up the SST's and the Atlantic side recieving warm southerlies although the strength at this stage is fairly slack but some retreat on the Atlantic side looks likely, one to watch for sure.

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Posted
  • Location: Brighton (currently)
  • Location: Brighton (currently)

10 days with no new posts in the height of the melt season?

That's unusual... no news is good news i guess.

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Posted
  • Location: Morecambe
  • Location: Morecambe
On 25/07/2017 at 14:08, karyo said:

10 days with no new posts in the height of the melt season?

That's unusual... no news is good news i guess.

Suspect its more because the interest in Arctic ice on this forum is fairly low in all fairness.

Extent is 5th lowest at the moment but it seems this year will head towards the 2007/2012/2015/16 type of years as the pack does look more vulnable to melting now than it did earlier in the melt season with holes popping up on the Atlantic side of the Arctic in particular whilst the Pacific side continues to slowly but surely gets melted away especially the ice near the East Siberian Sea - think its nearly fair to say there won't be a tongue of ice sticking out towards that region this year!

However in general, the pack seemed to be more compact this year than last year which makes sence as May and June have been largely dominated by winds compacting the pack but this has reduced the extent on the pacific side to quite low levels, only the Beaufort sea has seen ice starting to spread out during this melt season which can also be a bad thing for the ice also.

The models did hinted at cold and slack conditions, the slack conditions did not last as long as first thought and typically by the time the air did try and get cold enough, the winds started to pick up again and looks like we are heading for a brief dipole before it gets cut off by a medium strength low pressure system(which seemingly does have some cold air mixed in). What happens after that seems less clear cut but hints do seem to suggest an intense low could well be possible coupled with  high pressure over Beaufort which will produce a strong dipole but of course that may not actually happen.

I think to sum up my thoughts at the moment is that things could be a lot worse than they are given the dire volume we had during Spring and the low thicknesses but the Arctic is far from being out of the woods as far as this year is concerned and I do suspect we will get quite low again this year just purely on the ice thickness alone, most people seem to be predicting 2nd lowest and I would agree on that, perhaps being closer to 2012 than 2016.

Also to note, this has not been a 2007 year type summer which GW has for a few years predicted might of happened this year based on his 10 year cycle theory but the evidence is just there that if we do get a 2007/11 type summer then we would more than likely see an ice free pole and almost an ice free Arctic.

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

Again I'm still waiting to see just what that 'thinner ice' does do before re-freeze is called? If an 'average summer' does melt 2m thick FY ice then 1.5m ice should be no problem to melt? This week and those following ,are my best guess for when this ice would go so I will now watch to see if we begin to see losses we can't put down to weather alone?

I do not know if we will see any big storms over August/September but that might also lead to sudden drops in area as the ice gets tossed around in the ocean?

As for the cyclical 10 to 20 year cycle for the 'perfect melt storm summer' has our circulation now altered so much as to negate that cycle completely? What we have to get used to is open water from early in the season? We started off low over our , and the Pacific side of the basin so those peripheral waters have been gaining heat all summer. This ,in its turn, leads to a messy Autumn /early winter and the basin sheds heat and messes with the formation of the PV ( which then messes with the positioning of the Polar Jet?). We can expect this again over the start of re-freeze but will it be as extreme as last year?

We are also tip toeing into the time of year we see Yamal making headlines? Two years ago it was the funnels , last year the 'hillocks' and wobbly ground. I wonder what we will have this year?

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Posted
  • Location: Chisinau, Moldova.
  • Location: Chisinau, Moldova.
2 minutes ago, Gray-Wolf said:

Again I'm still waiting to see just what that 'thinner ice' does do before re-freeze is called? If an 'average summer' does melt 2m thick FY ice then 1.5m ice should be no problem to melt? This week and those following ,are my best guess for when this ice would go so I will now watch to see if we begin to see losses we can't put down to weather alone?

I do not know if we will see any big storms over August/September but that might also lead to sudden drops in area as the ice gets tossed around in the ocean?

As for the cyclical 10 to 20 year cycle for the 'perfect melt storm summer' has our circulation now altered so much as to negate that cycle completely? What we have to get used to is open water from early in the season? We started off low over our , and the Pacific side of the basin so those peripheral waters have been gaining heat all summer. This ,in its turn, leads to a messy Autumn /early winter and the basin sheds heat and messes with the formation of the PV ( which then messes with the positioning of the Polar Jet?). We can expect this again over the start of re-freeze but will it be as extreme as last year?

We are also tip toeing into the time of year we see Yamal making headlines? Two years ago it was the funnels , last year the 'hillocks' and wobbly ground. I wonder what we will have this year?

Hi,

Yet to see any relation to end of grow season extent and the low come September. Now, it could be things change over the next 6 weeks, but it would seem to take a storm, some winds or some ocean currents to dip below 2012. Why? Look at the temperature. 

 

Captură de ecran din 2017.07.27 la 17.42.48.png

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

You have to be aware that the 80N temps are pegged by the latent heat of fusion ( which is why the 'average line' stays so close to Zero?) once we are not seeing melting ice , and the ocean below is sealed, you see huge spikes in temps away from average?

When we see that period of the graph that sits above zero begin to throw such spikes we know we are in trouble as the latent heat of fusion is no longer 'chilling down' the area i.e there is no ice to melt.

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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

Really this has become a very tricky season to anticipate.

On the one hand there are the conventional metrics which paint not too bad a picture relative to the past decade (but still very poor compared to before then), but in the other we have those using visual imagery and finding that areas of ice represented as 50% or so concentration are in fact a sort of slush seemingly (much) less than half a metre thick that could 'flash' out in the space of a day or two without much notice. One mid-strength or more storm could achieve that.

I have my concerns that an ice pack consisting of countless very small fragments of ice with at least as many small spots of open water between may not be measured correctly even by the area metric given limitations of resolution.

Do we currently have a close mesh of slushy ice posing as a nice solid central area of compact sea ice? In these often cloudy, windy times it's hard to build a clear enough picture to say for sure.

 

This conundrum is leading on the ASI forum to a persistent cycle of post times between 'things look really bad from visual' and 'ah but the area and compactness metrics suggest we should finish quite a way above 2012 and perhaps even some way above 2016.'

I have to say though, I've read these 'not so bad' posts now and then for at least a month now... and extent has confined to keep pace with 2012 and 2016. Hence my concerns expressed above.

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

I think we are at a point of 'faith' in what we believe to be the state of the ice?

The only 'real measure' is melt out of existing ice and so we sit and wait.

If we believe the thickness measures were spot on then we might scrape through above 2012 but maybe not in volume which would be record low. If excess snow cover threw out the sat thickness then there may be a nasty shock on its way as we see areas of rubble drop out of the picture and a far less 'compact pack' emerge?

 

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Posted
  • Location: Morecambe
  • Location: Morecambe
On 7/30/2017 at 10:43, Singularity said:

Really this has become a very tricky season to anticipate.

On the one hand there are the conventional metrics which paint not too bad a picture relative to the past decade (but still very poor compared to before then), but in the other we have those using visual imagery and finding that areas of ice represented as 50% or so concentration are in fact a sort of slush seemingly (much) less than half a metre thick that could 'flash' out in the space of a day or two without much notice. One mid-strength or more storm could achieve that.

 

There was a storm over the Beaufort which 'flashed' a lot of ice out from the 29th to the 30th on the concentration images but this is now weakening and moving towards the CAB and the models have been hinting at least one more deep low could hit in a similar area.sometime in the future although there has been to much variation to place much faith in this.

Where will this year end up? If indeed the ice is more compact this year and it seems to be to me compared to 2016 then if conditions are right for the ice to spread out then the extent line could really slow down towards the end of the month but if the compaction continues then extent will keep on going down and will probably finish 2nd lowest as the ice does look pretty thin in parts especially towards Laptev where a hole has now developed despite weather conditions being cold there lately.

August is an interesting month as the shape of the ice pack changes quite dramatically during the month so its going to be interesting just how far the ice continues to retreat on the Pacific side of the Arctic, there is going to be no 'arm' of ice stretching out to the lower latitudes so I imagine the shape of the ice will be fairly rounded as it is now come September

Either way, as I said in my last post, this season is confirming more and more on the fear if we get a high pressure dominated summer like 2007/11 then we could be looking at an ice free pole and almost an ice free Arctic.

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Posted
  • Location: cheltenham.
  • Weather Preferences: if its warm i want sun..if its cold i want snow.
  • Location: cheltenham.

that bloke up near the straights is setting off on his attempt to sail to north pole..or see how far he can get.

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Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......
On 31/07/2017 at 12:26, Geordiesnow said:

 

August is an interesting month as the shape of the ice pack changes quite dramatically during the month so its going to be interesting just how far the ice continues to retreat on the Pacific side of the Arctic, there is going to be no 'arm' of ice stretching out to the lower latitudes so I imagine the shape of the ice will be fairly rounded as it is now come September

 

As with last year the ice left will predominantly be over the Trans Arctic Drift ( T.A.D.)  or above Fram. Should winter prove as stormy then a lot of that ice will be gone by spring ( as we saw last winter?) so we could again see low volume gains as any growth is masked by losses?

I suppose it is the way the basin is shaped that dictates where storms of strength can enter? Either Bering side ( which activates the T,A,D, or Svalbard side ( and activates Fram) t is as if the basin is set up to be ice free with the 'cogs' being storms entering the basin , and the conveyor belt the T,A,D and Fram?

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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

Copying over from the MOD thread in case it gets removed:

The Arctic situation is actually very interesting, if a bit alarming at the mo, with more than half of an already second-lowest extent of ice on record in a very thin and heavily fragmented state, with a fairly week storm having just managed to wipe out an unusually large swathe of ice in Beaufort while a stronger storm looks to hit much of the remaining Pacific ice starting  in 2-3 days time. Some serious wedges of relatively warm and moist air wrapping into these storms too. A quick atmospheric cooldown is desperately needed to combat the oceanic mixing/wave action feedbacks (but I'm not so far seeing much sign of anything sustained of that nature).

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Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

24_mslp500_arc.png?cb=473 48_mslp500_arc.png?cb=473 96_mslp500_arc.png?cb=473 

120_mslp500_arc.png?cb=473 144_mslp500_arc.png?cb=473 168_mslp500_arc.png?cb=473

I make that 4 days with tight pressure gradients on the Pacific side of the Arctic and 2 days very tight, with something resembling a certain infamous cyclone at least in terms of pressure gradients next Thursday.

This is all just one run from one model of course, but it does fit in with recent multi-model trends and tendencies. Rough times ahead in which we'll see to what extent thin and fractured ice turns the balance of power in favour of a relatively warm (at depth) ocean versus an atmosphere that looks to chill out nicely, albeit not without some warm, moist airmasses poking in from time to time;

144_mslp850_arc.png?cb=473 216_mslp850_arc.png?cb=473

We'll have to keep an eye on the roasting western U.S. given it's potential to feed exceptionally warm air into the circulation of these deep lows being advertised.

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