Arctic Sea Ice Discussion 2015-2016: The Refreeze.

[knocker]

 

[Singularity]

So it looks like the good work done by 2014-15 on the volume has been undone.

We still have that multi-year ice but it seems not to be keeping the volume up as high as I imagined it would.

The stage is set for unprecedented losses - but that's not to say that the actors will follow that script.

[Gray-Wolf]

Yup S. , all gone! Worse than that was the amount of 3rd year ice lost since December through Fram, and the amount now sat waiting to exit once we see northerlies once again over the Straight!

By May we will be seeing the end of the peripheral ice ( Okhotsk/Bering/Baffin/Hudson etc) exposing just how 'light' the central basin is on ice with the Atlantic ice pushed back toward 80N.

I'd also warn folk that since 07' the summer weather for ice melt has been average or cool without any consistent 'warm' weather summers. How long can we expect to maintain such a run without seeing a 'warm' summer over the ice?

In late Autumn 2007 a study on the cyclical nature of the 'perfect melt storm' summer found that we ought to expect one every 10 to 20 years with the two immediately before 07' only showing a ten year spacing.........so this means that 2017 is the earliest possible return of the 'perfect melt storm' of high melt and high export......

So , no 'warm summers' since 07' , no high export summers since 07' ( the record drops in volume and area/extent were fueled mainly by 'in -situ melt' as any view of melt season over Beaufort since 07' shows). We should also include at least 4 'rebound years' since 07' yet the basin enters melt season in possibly the worse state we have yet seen?

Hold on tight! I think we have an interesting summer ahead!!!

Edited April 6, 2016 by Gray-Wolf

[knocker]

Neven - PIOMAS April 2016

http://neven1.typepad.com/blog/2016/04/piomas-april-2016.html

[Singularity]

Fascinating comment by Oliver Del Rio on that Neven article, speaking of the record low sum of northern hemisphere 'white surface' for Feb-Mar, models projecting the -20*C 850 hPa isotherm as early as mid-April - two weeks head of the previous earliest departure (which he states to be early days of May in 1980, according to reanalysis) and the n. hem already building heat including the subtropics with temps already above 30*C at 850hPa from India to Africa, with 30*C at 2m reached in Bosnia already - among the earliest dates on record for this threshold to be met).

I've not verified just how extreme it all is, but apparently it's more akin to what might be expected a month or so from now. Interesting to think what that could mean for the magnitude of heatwaves as, when and where they manifest this summer. Sure, the hotter it gets, the more energy is needed to keep that temperature climbing, but it only takes fractions of a degree to see records topple. Including those in the Arctic (but hopefully the warmth will hang out at 50-70*N instead and in an unusually spread out fashion to avoid lethal heat... yeah, that's hoping for too much, isn't it?).

[knocker]

Beaufort under early pressure

http://neven1.typepad.com/blog/2016/04/beaufort-under-early-pressure.html

[Gray-Wolf]

I'm beginning to get quite fearful about the Arctic this summer? The record warm winter has proved to be quite damaging for the ice as the russians are finding whilst setting up their ice camp this year ( Barneo). They had to scrap their first attempt at a base as the  floe suddenly disintegrated under them. They located a 'new' floe nearby but this early a.m. the put up a face book post saying this floe was now disintegrating.

The floes are roughly the same size/thickness as used in previous years but the lack of cold inside the ice ( core temps) has reduced the tensile strength of the ice. How will this play out over melt season??? 

To melt out the ice you obviously have to raise the 'core temp' to zero ( or -1.8c but let's use 'Zero'?) so if that core temp is 5-10c warmer surely this means 'faster' melt out? Take two 1m cubes of ice under the same melt pressure. One has a -25c core temp and the other -17c. Do we expect to see different melt out behaviours for the two cubes?

The loss of tensile strength across the pack must also mean a lot more degradation of the ice ( break ups and cracking) , this also must accelerate melt by placing ice with huge surface areas ( as rubble) into liquid water......

[Singularity]

I have seen at least a smidgen of hope; CFSv2 projects a notably cool Arctic summer, perhaps due to a lot more cloud cover than usual - which could be due to the increased moisture exchange with the ocean?

Edited April 8, 2016 by Singularity

[BornFromTheVoid]

No sea ice extent updates for the NSIDC for a while  https://nsidc.org/arcticseaicenews/2016/04/sensor-on-f-17-experiencing-difficulties-sea-ice-time-series-temporarily-suspended/

 
Sensor on F-17 experiencing difficulties, sea ice time series temporarily suspended

NSIDC has suspended daily sea ice extent updates until further notice, due to issues with the satellite data used to produce these images. The vertically polarized 37 GHz channel (37V) of the Special Sensor Microwave Imager and Sounder (SSMIS) on the Defense Meteorological Satellite Program (DMSP) F-17 satellite that provides passive microwave brightness temperatures is providing spurious data. The 37V channel is one of the inputs to the sea ice retrieval algorithms, so this is resulting in erroneous estimates of sea ice concentration and extent. The problem was initially seen in data for April 5 and all data since then are unreliable, so we have chosen to remove all of April from NSIDC’s archive.

It is unknown at this time if or when the problem with F-17 can be fixed. In the event that the sensor has permanently failed, NSIDC is working to transition to either the DMSP F-18 or possibly the JAXA Advanced Microwave Scanning Radiometer 2 (AMSR2) on the Global Change Observation Mission – Water (GCOM-W) satellite. Transitioning to a different satellite will require a careful calibration against the F-17 data to ensure consistency over the long-term time series. While this transition is of high priority, NSIDC has no firm timeline on when it will be able to resume providing the sea ice time series. For background information on the challenges of using data in near-real-time, see the ASINA FAQ, “Do your data undergo quality control?”

[alr1970]

Greenland sees record-smashing early ice sheet melt

Quote

Almost 12% of Greenland’s ice sheet was melting on Monday3, according to data crunched by the Danish Meteorological Institute.

It beat by almost a month the previous record for a melt of more than 10%, on 5 May 2010.

“We had to check that our models were still working properly,”4 Peter Langen, climate scientist at DMI, told blog Polar Portal.

Edited April 13, 2016 by alr1970
missing link

[stewfox]

9 hours ago, BornFromTheVoid said:

No sea ice extent updates for the NSIDC for a while  https://nsidc.org/arcticseaicenews/2016/04/sensor-on-f-17-experiencing-difficulties-sea-ice-time-series-temporarily-suspended/

 

Where does the attached data come from ? Currently 13 168 647 kms 2 artic sea ice extent as at 12 april

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

 

 

Edited April 13, 2016 by stewfox

[stewfox]

6 hours ago, alr1970 said:

Greenland sees record-smashing early ice sheet melt

Interesting , lets see if they find issues with the data

[knocker]

10 minutes ago, stewfox said:

Where does the attached data come from ? Currently 13 168 647 kms 2 artic sea ice extent as at 12 april

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

 

 

Does it not say at the bottom of the page stew?

[Singularity]

But AMSR2 is still good so at least we have these obs:

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

...although they are somewhat alarming!

[stewfox]

10 hours ago, Singularity said:

But AMSR2 is still good so at least we have these obs:

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

...although they are somewhat alarming!

Extent has increased by 73,000kms in last 4 days. Too early to call it a Arctic recovery ??

Edited April 14, 2016 by stewfox

[Singularity]

1 hour ago, stewfox said:

Extent has increased by 73,000kms in last 4 days. Too early to call it a Artic recovery ??

What are you looking at? I'm seeing a drop of 200,000 or so over the past week .2 million km^2.

[stewfox]

20 minutes ago, Singularity said:

What are you looking at? I'm seeing a drop of 200,000 or so over the past week .2 million km^2.

I am looking at the spread sheet

Arctic sea ice extent you can see the increase. where do you see the 200,000 drop ??

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

The latest value： 13,179,840 km2（April 13, 2016）

13151679 9 April

13106111  10 April

1311888111 April

13168647 12 April

13179840  13 April

 

[Singularity]

20 hours ago, stewfox said:

I am looking at the spread sheet

Arctic sea ice extent you can see the increase. where do you see the 200,000 drop ??

https://ads.nipr.ac.jp/vishop/vishop-extent.html?N

The latest value： 13,179,840 km2（April 13, 2016）

13151679 9 April

13106111  10 April

1311888111 April

13168647 12 April

13179840  13 April

 

Now I see the bounce! For some reason even after refreshing I could only see to 10th.

A gain of 73,000 to the 13th, followed by a loss of around 20,000 to the 14th. Potentially quite a big 'wiggle' for the time of year, by historical standards (considering timescale of just 4 days).

Obviously the big deal is where the extent gains were and whether they were more to do with ice moving around as opposed to growing. Something I wish I had the time for these days, but alas, not really.

Edited April 15, 2016 by Singularity

[Gray-Wolf]

Your messing with " Spurious data" guys! Stick to JAXA until the F18 sensor is in use ( for the NSIDC and DMI). JAXA is still on the downward trend and one look at the charts will tell you what kind of a shove Fram is getting a.t.m.!!! Once Fram has achieved 'flow' then we have over 1/3 of the basins 'good ice' queued up to take the fall so expect volume to take a hit over the next period?

Edited April 16, 2016 by Gray-Wolf

[knocker]

2015/2016 Winter analysis

Quote

The extraordinary temperature anomalies in the Arctic since the start of the year haven't gone unnoticed in quite a few media outlets, and I apologize for not having joined the fray of actuality. On the other hand, context trumps actuality, as we need to compare to previous years and get a feel for what this prelude to the melting season may mean. In that sense, I'm early with this year's winter analysis (compared to last year).

Let's start studying like crazy, shall we?

http://neven1.typepad.com/blog/2016/03/20152016-winter-analysis.html

[BornFromTheVoid]

ADS extent dipped below 13 million km2 4 days earlier than any previous year recorded. Yesterday it dipped below 12.9 million km2 6 days earlier than any previous recorded year.

[knocker]

The Arctic is facing a decline in sea ice that might equal the negative record of 2012

Quote

Bremerhaven/Germany, 21 April 2016. Sea ice physicists from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), are anticipating that the sea ice cover in the Arctic Ocean this summer may shrink to the record low of 2012. The scientists made this projection after evaluating current satellite data about the thickness of the ice cover. The data show that the arctic sea ice was already extraordinarily thin in the summer of 2015. Comparably little new ice formed during the past winter. Today Dr Marcel Nicolaus, expert on sea ice, has presented these findings at a press conference during the annual General Assembly of the European Geosciences Union in Vienna.

http://www.eurekalert.org/pub_releases/2016-04/awih-tai041816.php

[Singularity]

The way I see it, an average summer of temperatures probably lands us between 2007 and 2012, while one with a single month even close to July last year sends us down to 2012 levels, and one as insane as 2007 sends the ice crashing to unfathomable lows. 

I wonder if, much as an ice cube shrinks ever faster due to an increasing surface area to mass ratio, the Arctic sea ice extent might behave in a similar way? The jump between 2007 and 2012 certainly gives the impression that it might. I can envision some degree of counter by the reduced solar radiation intensity as you move further poleward, but would it be enough?

Anyway, perilous times, unless summer turns out unusually cloudy/chilly. I believe 2013 and 2014 (or at least one of the two) were of that nature? It certainly helped with the ice volume and it's a real shame that the gains have been obliterated over the past year.

[Gray-Wolf]

15 hours ago, Singularity said:

The way I see it, an average summer of temperatures probably lands us between 2007 and 2012, while one with a single month even close to July last year sends us down to 2012 levels, and one as insane as 2007 sends the ice crashing to unfathomable lows. 

I wonder if, much as an ice cube shrinks ever faster due to an increasing surface area to mass ratio, the Arctic sea ice extent might behave in a similar way? The jump between 2007 and 2012 certainly gives the impression that it might. I can envision some degree of counter by the reduced solar radiation intensity as you move further poleward, but would it be enough?

Anyway, perilous times, unless summer turns out unusually cloudy/chilly. I believe 2013 and 2014 (or at least one of the two) were of that nature? It certainly helped with the ice volume and it's a real shame that the gains have been obliterated over the past year.

Agreed with those concerns and I'll raise you 'crackopalypse' fracturing across Beaufort!

Since 2013 this late season smashing of Beaufort has not appeared to have much impact but was this due to 'weather' and not it being a 'nothing' in pre conditioning of the ice. As you note increased surface area increases the heat drawn into the core of the ice and speeds up melt so what will happen if Beaufort basks under sun for the majority of summer?

The other thing is the mass loss that we must be seeing from Fram export a.t.m.? We have lots of older ice stacked up in the feed into Fram so should we keep northerly flow from there we stand to have already peaked in volume ???

The only other thing troubling me is whether the warm incursions over winter has lead to the ice not reaching the low temps, at its core, than after a winter with 'normal' Arctic temps? Does this shorten the time needed to melt out that ice compared to other years?

As we have become accustomed to saying " it all depends on the weather"!

[Singularity]

The potential losses from FRAM certainly alarm me. A double negative when based in the UK; cool and changeable here while the Arctic suffers.

Interesting point with respect to less cold winter impact; the ice has not lost as much energy over the winter so it seems logical that less input will be needed to bring the ice up to the phase change threshold.

Seeing the models trend toward stronger Arctic blocking returning in the 8-10 day period has caused much depending of my brow furrows today!