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With NSIDC call in ice max I think we can now step over into the melt Season thread

http://nsidc.org/arcticseaicenews/2018/03/arctic-sea-ice-maximum-second-lowest/

"Arctic sea ice appears to have reached its annual maximum extent on March 17. This is the second lowest Arctic maximum in the 39-year satellite record. The four lowest maximum extents in the satellite record have all occurred in the past four years. NSIDC will post a detailed analysis of the 2017 to 2018 winter sea ice conditions in our regular monthly post in early April."

and Neven has this to say;

http://neven1.typepad.com/blog/2018/03/the-2018-melting-season-has-started.html

"For a while it looked like the record for lowest maximum was going to be broken for the third year in a row, especially after an extreme warm eventshook the Arctic. But this anomalous heat was followed by anomalous cold, which was just enough to nudge JAXA sea ice extent above last year's record low maximum. By 13 thousand km2, to be precise, which is around 0.1% of total sea ice this time of year."

So, off we go!

 

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20 hours ago, knocker said:

 

Right across the exceptionally low Bering sea ice. I am seeing talk of anomalous warmth ahead of it on southerly winds which may result in mostly open water in the Bering by the time the strong highs take shape.

So if something at least loosely akin to the above pattern does develop, the stage will be set for an extraordinary amount of energy input into the Arctic waters on that side for the time of year. With anything less than a very cloudy summer over there, I wonder just how high the heat content could go by Aug-Sep if this potential event takes place?

- which brings to mind how educational it will be to see to what extent such early open water leads to moisture feedbacks that increase cloudiness and encourage more LP development. Especially if GW's proposed low solar links to more high-latitude blocking prove to be along the right lines.

index.php?action=dlattach;topic=2278.0;a

Not sure if I should be posting attachments across from the ASI site but here's the Bering-Chukchi region showing signs of breakup that weren't observed until 3-4 weeks later in 2017.

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Posted (edited)

Agreed Singularity!

The Energy that could be potentially absorbed by the Pacific side of the basin will mean another year with the Polar night Jet being molested as it tries to form and 'off centered ' when it does!

To already have these worries right at the start of melt season is shocking.

Then we have low ice again over the Atlantic side of the basin ( and the clear skies we have been seeing there) so another area with the potential to gain huge dollops of energy over melt season.

To go into to another melt season with the potential for the type of disruption to northern hemisphere circulation come autumn that we have seen these past years is just another confirmation of how altered the basin now is. And all before we see how low ice goes over the melt season i.e. winter is now setting up the melt season more than ever before by allowing dark water from the get go.

Apart from the energy to disrupt the atmosphere above, come Autumn, we also have hostile waters produced ever deeper into the basin. By August half of Beaufort will be melted out and the open waters revealed gaining heat and becoming hostile to ice drifted into it. The same will be true at the top of Fram with warmed waters and the extension of the gulf stream at the surface taking ice that is flung its way?

So the best we dare hope is another winter of plunges and WAA and the worst? well who knows especially if we build a head of melt momentum over this first part of the melt season?

Edited by Gray-Wolf

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Well the past week kicked off melt season with both JAXA and NSIDC seeing the first major losses ( 3rd largest drops before June first on record?)

With NASA worldview now seeing the whole basin it is worth taking a peep from time to time as the pack now begins to break apart under the stresses of wind and wave with old breaks easily coming apart as the 'new' ice glue holding the floes together gives way.

The HP that has set up over Beaufort is now beginning to pull the pack aprt as it rotates with the high. With Bering over 4 weeks ahead of time there is plenty of open waters for ice to drift out into.

Also ,for the first time since 2012, we look like getting to May first with the potential of a perfect Melt storm for summer still a possibility. Since 2013 by May 1st that potential had already been busted as cloudy, retentive weathers put it on hold.

With my recent wondering over low solar and HP domination over early melt season it will be an interesting few weeks!

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Posted (edited)

192_mslp500_arc.png?cb=811 240_mslp500_arc.png?cb=811 12_252_mslp500arc.png?cb=811

A couple of days ago, the high pressure signal across the Arctic was pretty much gone in favour of slack lows, and I was wondering of this year would become yet another to take on an ice-retentive state just as the sun starts to become strong enough to seriously impact the ice across the entire region. 

Since then, however, the trend has strongly reversed and conditions are now looking very troublesome as May 2018 gets underway, particularly if ECM is closest to the money.

This sort of pattern was being advertised prior to that change of heart a couple of days ago, so it's one that's made a comeback, which typically indicates something well-rooted in the teleconnections - perhaps the active MJO that has made it into phase 3 (contrary to model forecasts of a week ago which decayed in in phase 2). 

My concern level for the potential events of the 2018 melt season has now gone into the very intense shades of red.

Edited by Singularity
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Worrisome this evolution of the Ocean entrances.

Our side of the basin have had low ice since the early noughties so we tend to overlook it but since 2014 the Pacific side has been playing catch up.

This leaves room for the basin ice to 'relax' into so allowing rapid pack breakup of the central ice whilst allowing surface warming of the open water sp providing 'hostile zones' for any ice drifting into it later in the season.

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The open water in bering straights/chukchi/Beaufort is now allowing the general collapse of Beaufort sea ice over the past couple of days whilst we have seen central basin ice relax out to Svalbard's N.Shore allowing for some of the lowest sst's of the past 12 months...in spring!!!

Japan have a run of public holidays today and later in the week so JAXA numbers will be missing.

I think NSIDC saw a 2 day loss of 129k over the 28th/29th.

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We are seeing , I believe, the Pacific side of the Arctic basin undergoing the change our side went through in the noughties. This leads to early warming of the waters entering the basin through the Bering Straights and so provides 'hostile coditions' on the Pacific side of Beaufort come bottom melt end of the melt season?

In its turn this allows for the fragmentation of the central basin ice and its transport under wind/current forcings.

The other thing to note is that we are now into May and we are still under a HP dominated Basin . We have not seen this since 2012 and should it persist through May will lead to a great deal of melt momentum for the rest of the season.

The lack of Freezing Degree Days (FDD's) over the weinter just gone means the ice is less resilient to melt out than in a 'normal year' that has seen frequent deep cold over the ice.

The perfect melt storm also has the HP dominance element to it along with low pressures positioned to feed ice into Fram. We have seen central basin ice slowly migrate toward Svalbard but ,as yet, no constant forcing there. should it develop then the 'lift offf' of ice along the Northern shore of Greenland back in Feb will make transport to Fram 'smoother' with no deep ,shore fast ice, to hinder its progress along that section of coast.

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Posted (edited)

I always find this talk of high pressure at this time of year quite interesting because for me there is a difference between a high that forms over the basin itself and a high that ridges on from the landmasses.

What I seen in general for the most of April is a high that is formed over the basin, this too me is not the worse thing as upper and lower air temps will be quite low and clear skies at night will still allow temps to fall away significantly and for ice thickening to still continue somewhat. In May this is less of an affect but upper and surface temperatures can still be fairly cold abd surely the cold tempertures mean there is less likely of melt ponds forming which of course can be a major factor later on in the melt season.

If a high ridges in from the landmass and in particular the Beaufort high, this can lead to heat coming in from the landmasses and for ice to pull away from the coastline and we saw quite an extreme case of that during 2016. May 2011 was by far the worse month for the Beaufort high forming and quite extraordinary amount of heat coming in from Alaska, conditions did take a remarkable turnaround at the end of the month however and the open water in the Beaufort closed up somewhat but no doubt melt ponds would of been quite widespread then.

May 2016  saw good pre conditioning also I believe but June was quite chilly however the state of the ice was not good hence the 2nd lowest extent in the end.

As far as current conditions are concerned then after a period of fairly chilly conditions with the laptev area being fairly stormy, we are now seeing strong Southerlies going to hit the Barants Sea and attack that extensive ice edgr and no doubt will start to melt it and as the ice is quite high compared to recent years and because that ice to the east of Svalbard is not all that thick, we may see some large drops coming? 

 

Edited by Geordiesnow

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Posted (edited)

 

Edited by knocker
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Hi Knocks!

This seems to have crept up on many ice watchers. With min ice looking to have 'stabilised' folk had backed off in interest but then the 2015 Christmas pole melt woke people back up to what was going on with interest being shown to the rapid drop off in Freezing Degree Days ( FDD's) illustrating the lack of cold ice was being treated to over winter.

No deep cold = thinner,warmer ice.

It makes you wonder just what the min figure would have been had we seen an 07'/2012 melt season?

We should also not be lulled into a false sense of security with recent cloudy ,cool melt seasons.

With final figures not being that dissimilar from what it took a 'perfect melt season' to give us only a decade ago we should all be aware of just the scale of losses any repeat of that synoptic would bring.

We are in Low Solar and this year is still being dominated by HP and warmer temps beyond 80N that the long term average ( already 2017 had dropped below the long term average by now?) so did low solar play a part in the sea ice lows of 07'/2012? We are about to find out!

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Posted (edited)

A somewhat concerning evolution on the recent ECMWF runs, with an anticyclone over the Arctic Ocean taking warm air in from the anomalously ice-free Bering Sea area:

http://www.wetterzentrale.de/maps/ECMOPNH12_168_2.png

The Arctic was relatively cold for recent years during March and to a lesser extent April, but we've already seen the ERA-40 reanalysis for north of 80N show a large spike into early May:

http://ocean.dmi.dk/arctic/meant80n.uk.php

Correspondingly, after a relatively modest overall retreat of the Arctic sea ice in April, it's started to fall off a proverbial cliff in the NSIDC sea ice extent updates and this looks likely to continue for at least another week.

 

Edited by Thundery wintry showers

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The DMI 80N spike is the largest departure we have measured in the DMI 80N record with only 06' coming close to seeing such early warmth?

Our input of warmth has also see the ice edge around Svalbard pushed back over 50km with noticeable melt at the ice edge.

I have seen nothing to allay my fears that low solar sees more active ice melt seasons ( 07'/2010/2012) with plenty of sunshine over the basin along with the WAA out of the Atlantic.

We learnt , back in the early noughties that the loss of ice/snow cover can modify climate up to 1,500km away so the ridiculously early open water in Bering will impact the Pacific side of Beaufort this melt season. We are now accustomed to seeing this side of Beaufort ice free by August and turn into a 'hostile environment' for any ice floated into it. If we keep seeing H.P. over beaufort ( beaufort High) then later in the season we may see pole side ice spun into melt zones with warmer waters flowing into the pole side in the return circulation?

Should we see frequent L.P.'s entering from the Atlantic we may also see the trans polar drift/Fram exporting 'good ice' leaving open waters behind.

We will be seeing our first melt ponds becoming visible on sat images over the coming weeks, will this year see a return to the extensive melt ponding of last low solar?

( I may be wholly wrong in attributing our recent record low years to low solar but it did coincide with our last low solar but also the 'return' period for the 'perfect melt storm synoptic' of 10 to 20 years?

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On 08/05/2018 at 00:55, Thundery wintry showers said:

A somewhat concerning evolution on the recent ECMWF runs, with an anticyclone over the Arctic Ocean taking warm air in from the anomalously ice-free Bering Sea area:

http://www.wetterzentrale.de/maps/ECMOPNH12_168_2.png

The Arctic was relatively cold for recent years during March and to a lesser extent April, but we've already seen the ERA-40 reanalysis for north of 80N show a large spike into early May:

http://ocean.dmi.dk/arctic/meant80n.uk.php

Correspondingly, after a relatively modest overall retreat of the Arctic sea ice in April, it's started to fall off a proverbial cliff in the NSIDC sea ice extent updates and this looks likely to continue for at least another week.

 

I don't quite see that set up your describing(as the flow is coming in from the Alaskan landmass rather than the Bering Sea) but as GW says, the Beaufort high is setting up(which does tend to happen at this time of year and is not all that unusual) and they can be quite hard to shift also.

Lots of variations from run to run as expected but the common theme does seem to be high pressure over Beaufort and lower pressure over Laptev and this means the infamous dipole which is not good news for the ice. Wait and see how it develop as variations from run to run  will continue but a strong flow in the Beaufort sea area does look likely at least for a couple of days which would then suggest open water will develop in the Beaufort although not to the extent of 2016.

Also an area of interest is the Greenland Sea, fram export is looking minimal for the foreseeable future(which is a good thing) but potentially warm air hitting the east coast of Greenland and SST's to the east are high so it will be interesting how much ice will cling onto Greenland by the end of the month.

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8 hours ago, Geordiesnow said:

Also an area of interest is the Greenland Sea, fram export is looking minimal for the foreseeable future(which is a good thing) but potentially warm air hitting the east coast of Greenland and SST's to the east are high so it will be interesting how much ice will cling onto Greenland by the end of the month.

O.T. but we have seen a change , this past decade, in Fram's behaviour. Low export means sluggish waters which warm up into 'hostile zones' for any ice pushing that way. By summers end ice will not make it to Fram mainly as it melts out before it gets to the north of Svalbard?

All winter we saw high SST values south of Svalbard and this was eating at the edges of the ice flow out of the basin.

this year it looks as though Bering is joining in the fun with a crazy early melt out so potential to warm and flood those warm waters into the west of Beaufort. Should the Beaufort high stick around and the Gyre become active this will deliver ice into the melt zone in the west and warmed waters toward the pole?

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Arctic_AMSR2_nic.png

The winter ice drift/breakup has left our side of the basin in quite a mess!

I've not seen an early May concentration map with such low ice so close to the pole.

Of all the years we could do with cloudy/cool ice retentive conditions over high insolation it is this one!

As it is the Pacific side is looking likely to see the Beaufort high set up and an empty Bering means warmed air pushing around it over the siberian side of the basin.

To early to make a call for the season but it still positioned to see high losses if we carry on in this vein!

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The Arctic sea ice extent is currently tracking clear second lowest after 2016.

https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

However 2016 had a marked drop-off in the melt rate in June so we will probably need another cloudy cool June over the Arctic Ocean to avoid having the lowest sea ice extent on record by the end of June.  There is a marked divergence between today's GFS operational runs and its ensembles, with the operational runs suggesting a relatively cyclonic pattern setting up over the Arctic Ocean at around day 10, but in contrast the ensemble mean is suggesting a signifcant chance of the Arctic dipole anomaly setting up.

GFSAVGNH00_252_1.thumb.png.eb62253c1adb0b52d128c397f104c72d.png

The latter would be a concerning evolution in view of the potential for the atmospheric circulation to take warm air from the open Bering Sea over to the pole. 

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The dipole that the models showed did not really come off in the end however there does seem to be a dipole of a different sort developing in the coming days with a intense warm spell hitting the laptev and perhaps the Kara Sea also with pressure high here whilst a deep low could be centred near the pole. One to watch especially with the large opening in the laptev already.

Be interesting how the ice around Franz  Josef land reacts to this current storm as its been quite stubborn to melt thus far although the ice further North does look a lother more fragile.

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When you look at the heat to the south of Siberia that this coming arctic cyclone will draw over it we should expect both a tumble in N.hemisphere snow cover and a rapid onset in melt across the region.

If the forecast verifies then we will see high numbers over the next week or so?

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Hard to say how much this spell of weather will affect extent numbers but the potential is there to cause some serious melt ponds forming on parts of that supposed thicker ice on the Russian side of the Arctic  and for the laptev bite to become a whole lot bigger.

The million pound question will be just how much will these strong winds affect the fragile looking ice in the northern parts of the Kara Sea I predict we could see a split of the fast more solid looking ice near FJL and the main ice pack. Interesting 5 or so days coming up.

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Posted (edited)

 

Edited by knocker

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Hi Knocks!

Maybe Svalbard's move from 'homegrown ice' to imported iceand the general evolution of a more mobile pack explains both the mobility and the rapid losses? I think the Polar Bears had a 2 week window of ice contact with the north shore earlier this melt season to get onto the ice to feed. If not then they are stuck there for another year?

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