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Arctic Sea Ice Discussion 2016-2017: The Refreeze.

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2 hours ago, Singularity said:

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 :)

Great post.

No idea where it will end up by summer, just trying to figure out where it can end up by March end.

It's quite easy to imagine a few events combining in Spring and Summer leading to something spectacular, but the question is will they. And I guess, how much does the starting point help that. For the past 10 years, it is hard to find a correlation between high starting point and low finishing point, so that to me suggests that whatever happens in Spring or Summer, or even both, is a much stronger overriding factor than where it starts come the high season.

 

 

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48 minutes ago, jvenge said:

Great post.

No idea where it will end up by summer, just trying to figure out where it can end up by March end.

It's quite easy to imagine a few events combining in Spring and Summer leading to something spectacular, but the question is will they. And I guess, how much does the starting point help that. For the past 10 years, it is hard to find a correlation between high starting point and low finishing point, so that to me suggests that whatever happens in Spring or Summer, or even both, is a much stronger overriding factor than where it starts come the high season.

 

 

Hello - which measures have you considered for the starting point? Something I would very much like to look into if I can find the time some day is what correlation exists when considering sea ice area and volume as opposed to extent, or even the quality in terms of core temperatures but I expect data for that is hard to come by or doesn't exist in any consistent form going back far enough in time. 

In fact, it's possible that this year's sea ice area, volume and quality combination is so far below historical cases that we're in uncharted territory anyway... what a fun (!) time to be involved in climate science :crazy:

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1 minute ago, Singularity said:

Hello - which measures have you considered for the starting point? Something I would very much like to look into if I can find the time some day is what correlation exists when considering sea ice area and volume as opposed to extent, or even the quality in terms of core temperatures but I expect data for that is hard to come by or doesn't exist in any consistent form going back far enough in time. 

In fact, it's possible that this year's sea ice area, volume and quality combination is so far below historical cases that we're in uncharted territory anyway... what a fun (!) time to be involved in climate science :crazy:

Only looked at extent for for correlation between how low or high it finished up at in September. Like you, I'm not sure where I can dig up the volume for the past decade.

However, extent to extent gives a clue. So, start of April extent doesn't appear to have a bearing on the September extent. Or, if it does, not enough to outweigh whatever nature is throwing its way in Spring and Summer. 

I must admit I haven't looked at volume at the start of April and volume for September to see how the correlation is there and if that provides a different signal. 

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The prospect of a sunny high over the basin through high insolation has to be the dread fear of anyone who wants to see ice ( and associated high albedo) in the basin over the summer months!

This , in the workings of the old Arctic climate, is the earliest year we could expect the return of the 'perfect melt storm' scenario. How , and why, did we used to see a 10 to 20 year return to a summer of high melt and high export? Are any of the forcings still there that allowed such events in the past? Is the run in to low solar somehow involved with the north Atlantic blocking over winter slipping into Barentsz to join up with the Beaufort high?

As singularity points out any of the high insolation months is probably enough to push us into a spiral of losses that only re-freeze would halt. If there is plenty of open water then the heat it would accrue over such a high forcing ( sunshine 24/7 for 4 weeks??)  would then dominate any ice drifted into that area.

Ice Quality? Well no Crackopalypse event this year ( so far?) ? Take a look at the ice now visible on MODIS   https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2017-02-22&z=3&v=-1400576,1640704,-1050880,1804032

and you can see that the ice is so degraded it cannot form straight lines any more with the ice crumbling into the remnant chunks we last saw in September? Where two leads intersect the point of contact just becomes a melange of tiny floes?

Has the period of crackopalypse been and gone with the resultant pack now too denatured for those pressure to impact any more and what does that mean for the ice once summer temps arrive?

 

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I do wonder if the unusually stormy winter has seen the usual freshwater layer disrupted to such an extent that a lot of the ice that has formed is tainted with salty deposits. Someone needs to get over there and tuck in to see what it tastes like :laugh:

Edited by Singularity

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I too worry about the halocline over our side of the basin? The open water is obviously now just normal ocean with no halocline present at all but how far did the wave/swell pass under the ice front? We saw the ice retreat to past 85N in December so we must expect that there was some mixing in toward the pole? And is the extension of the N.A.D/gulf stream only able to occur now the halocline is gone?

Bering appears to save the Beaufort side from similar mixing but if the ice is all gone by late June then weather over there will still mix out the fresh water lens over the gyre.

We have now seen the majority of winter and it has been record warm throughout. What will we see over the first third of melt season?

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Is there a good chance now that the upcoming summer will break the annual record low based on whats been happening over the last few months? Or is it impossible this far out to determine roughly what that low point will be?

Edited by Styx

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We all saw what became of last years ice after a winter that was not as impacted as the one we've just witnessed. We know we are lowest in all metrics as we approach the melt season. We know what a poor melt summer was able to do to last years pack.

In the past the final numbers could not be guessed at due to the varied impacts on melt that weather over the season caused. I personally believe we are moving away from such uncertainties and toward a far more 'certain' end result of every melt season?

If we repeated last years weather then we know we would fall lower than 2016 as we begin with less ice.

We also know that the ice we have has not seen anything like the temps we are supposed to see over winter ( FDD's) and so will take less energy to warm them up to melt temps?

The ice at min last year was well dispersed and individual floe size was the smallest, overall, we have seen so this winters pack is a mix of First Year ice and degraded floes. It is reasonable to imagine that this pack will also break apart readily and so become very mobile.

2017 is the earliest year we can expect the return of the perfect melt storm. If we saw the basin suffer a 2007 like summer then I honestly believe we would end up 'ice free' ( sub 1 million ice remaining) but anything that gives us clear skies over any of the 3 months of peak insolation will leave us in trouble.

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38 minutes ago, BornFromTheVoid said:

That volume anomaly... wow.

piomas-trnd4.png

That's less than what it would be in June...... Scary!

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2 hours ago, BornFromTheVoid said:

That volume anomaly... wow.

piomas-trnd4.png

This is the figure we need to be looking at to determine what might happen during the summer. Its all well having an extent or area close to average, but if there's actually much less volume of ice, then it takes less energy to melt it out.

If this anomaly were to continue to the ice minimum in the Autumn, then we'd have half the volume of 2012.

If we were to have an exceptionally warm spring and summer up there then we'd be looking at not much being left. An interesting season to come, what effect will it have on weather patterns?

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A quick messy graph.

On the primary y-axis is the previous maxima (blue) and the last 39 days of extent (green).

We've the current difference from the previous maxima shown by the red bars and using the secondary y-axis.

So, still 105k off last year's max

All NSIDC and 5 day average

svmpbaz.png

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We saw last year what the lack of winter conditioning meant to the ice? We had plenty of observers calling for a high finish when the high insolation months proved to be cold and cloudy but we all saw where we ended up with extent tied for 2nd place with 07'  and area in 2nd but much closer to 2012 record low ( and probably beating it due to the dispersed nature of last years final pack?).

I have real concerns that we have a pack , this year, that has a large proportion of ice that will not last out the summer months? No matter what weather the Basin sees that , just like peripheral ice/Hudson bay ice it will all be gone by august. We might still need a 'perfect melt storm' to go ice free but with less ice and less winter conditioning this year ( lowest volume by quite a way and Freezing Degree Days far less than last year) how dare we expect to finish above 2016 even with the same dire summer?

And , of course, this is the first year we might expect to see the return of the 'Perfect melt storm' whilst being told to expect an El Nino forming up..........

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If 2017 sets a new recored for lowest min ,it will a 5 yr pattern. 2007, 2012, 2017.

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After 2007 the Science looked at the repeat time for 'The Perfect Melt storm' synoptics and found a 10 to 20 year pattern with the two prior to 07' respecting the 10 yr gap. If we do see a record low it could be that such events are halving in their 'wait times' going from 20 years to 10 years and now to 5 years?

With other 'ice loss' we have seen doubling times for mass loss reduce as melt becomes more active so why not Sea ice?

There has to be a 'cut off' point though? Once we see so little ice at ice max to realistically last through a melt season the 'record low' years will be over and we'll move into 'record earliest melt out' measures?

But I get ahead of myself ! First we need to study the impacts of increasing amounts of open water under sun for increasing periods of time. Once we have a proper handle on this then we can project forward to see how we should prepare for future shocks from the extremes that low ice appear to drive from extreme rainfall to polar plunges.

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1 hour ago, Gray-Wolf said:

After 2007 the Science looked at the repeat time for 'The Perfect Melt storm' synoptics and found a 10 to 20 year pattern with the two prior to 07' respecting the 10 yr gap. If we do see a record low it could be that such events are halving in their 'wait times' going from 20 years to 10 years and now to 5 years?

With other 'ice loss' we have seen doubling times for mass loss reduce as melt becomes more active so why not Sea ice?

There has to be a 'cut off' point though? Once we see so little ice at ice max to realistically last through a melt season the 'record low' years will be over and we'll move into 'record earliest melt out' measures?

But I get ahead of myself ! First we need to study the impacts of increasing amounts of open water under sun for increasing periods of time. Once we have a proper handle on this then we can project forward to see how we should prepare for future shocks from the extremes that low ice appear to drive from extreme rainfall to polar plunges.

I think you are getting slightly ahead of yourself but I do admit a record low for this year does seem rather likely it has to be said with such low volume and thickness being shockingly low also.

You keep mentioning about last year but we got to remember some factors about last year in respect that there was early openings in Beaufort which caused open water all along the Alaskan coast, the weather patterns during May was some of the worse you could have for so early in the season with frequent WAA heading right into the Basin and even though June and July saw more in the way of favourable weather patterns, you still get the case of more localised cases of very warm air entering the basin producing further melt. Then the near of August we saw one of the strongest dipoles you could see and it was quite stormy which pushed the ice together causing further melt.

I don't think we will see an "ice free" Arctic by September but I do think an ice free pole is more than possible, will that be from the Pacific side of the Arctic or the Atlantic side because the ice to the East of the pole towards Laptev looks rather thin according to HYCOM.

 

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It might just be my 'seeing' things wrongly but last summer saw a lot of open water beyond 80N and just before the DMI 80N temp graph began to cool for winter I'm sure there was a small spike in the temps that are normally pegged around freezing by the latent heat of fusion as the ice melts?

What I will be watching is for that graph to break with the 'pegged to freezing' behaviour and show us temp spikes showing us a lot of open water which is warming ( and not held down by melting ice?). If ever there was an indication of changes over summer it will be that line rising to 3 or 4 degrees C.

As far as 'repeating patterns' I really do not have a clue! Can we rely on 'old ' patterns of weather repeats in the basin any more or has too much changed to circulation/temp/humidity over the basin these days for them to stay true?

Of course my not knowing means that I cannot discount the return of high melt/high export weathers across the basin for the duration of the melt season either?

 

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Quote

Lowest maximum on record (again)

After a drop of almost 262 thousand km2 in just three days, it looks highly likely that the maximum for sea ice extent was reached two weeks ago, according to the data provided by JAXA, the Japan Aerospace Exploration Agency (via ADS-NiPR ; it used to be provided by IJIS).

It's a new lowest maximum record, and the third time in a row that extent stayed below the 14 million km2 mark. The previous lowest max on record was reached in 2015 (13.942 million km2), almost beaten last year (13.959 million km2), but this year SIE went lower still and peaked at 13.878 million km2.

http://neven1.typepad.com/blog/2017/03/lowest-maximum-on-record-again.html

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Are we going too see the laptev bite making an early appearance this year I wonder? If the current set up carries on into April I think this is more than a strong possibility imo. In the last 2 years, the laptev bite was late to form but on the other hand Beaufort opened quite early, especially last year.

Does look like if current conditions carries on, we could see a 2014 type of opening which extended quite far into the basin quite early on and with the ice in a weaker state than in 2014 then that would spell trouble I feel. The worse case set up probably be if current conditions carries on for the next few weeks then we see a major switch with a high pressure cell setting up over Beaufort and low pressure over Alaska creating a strong wind gradient which could start pushing the ice away from the Alaskan coastline, the ECM hints at this in the longer term and from what I see from weather charts from previous years, its a weather pattern that does tend to occur quite often in April.

Could also someone point me where I can find charts from last year on the Breman site? I'm able to find the concentration maps for all the other years and make comparisons but sadly not with last year.

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2 hours ago, Geordiesnow said:

laptev bite

Please what are you referring to?

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I worried you might be on Honeymoon or summat?

Thanks for all the effort you put in to bring us these stats BFTV, it is muchly appreciated , really it is!

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6 hours ago, Snipper said:

Please what are you referring to?

Its where a polyna forms in the Laptev sea area which is down to a scientific reason(someone more knowledgable may know more than me) aswell as natural factors such as if we get frequent winds from Russia, the polyna is more likely to form and be quite large whereas the polyna is less likely to form as large if we get off shore winds from the interior of the Arctic.

An example of the "Laptev bite"

 

Laptev Bite.png

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