Arctic Refreeze Discussion: 2014/2015

[Steven]

No, it doesn't. You were right the last time, so I thought I'd give you the benefit of the doubt this time, but now you are wrong. Not sure how you came up with your dotted graph, but those are not my values. Guess it's just guesswork? 

I just double-checked my calculation, and couldn't find any error.

Could you provide the equation of the (quadratic?) polynomial that you are using for Annual Average Extent, please?  (In the topmost graph in your Reply #246 upthread).  I've been assuming that you are using a quadratic polynomial, but perhaps you were using some higher-degree polynomial (e.g. cubic)?

Note that the graph that I posted upthread is for the usual IJIS extent  (i.e., no annual averages or stuff like that).

[viddaloo]

It would be much more fun if you submitted your own original work with estimates for every day till the end of February. Then I could scoff at that if you were proven wrong by the Arctic itself 

BTW, and this is a version of the question above, what do you think are realistic extent values for every day in February 2015?

[Jim Hunt]

Yesterday's Hamburg AMSR2 reveals an interesting feature north of Greenland:

[jdallen]

Yesterday's Hamburg AMSR2 reveals an interesting feature north of Greenland:

Fascinating!  I'd read elsewhere on the forums (Nares thread maybe?)  that wind has been pushing the pack north, even while flow through the Nares straight has continued unabated.  The feature your image shows may be visible evidence of it.

It similarly is evidence of a rather obvious lack of "fast" ice across northern Greenland....

[viddaloo]

Add some heat to the equation, and we may even see the scenes of a massive km's wide river transporting giant flows of ice from the north of Greenland down to the Nares, that we saw through the sat images on Wednesday. Scientists overwhelmingly agree heat is not good for the ice.

[viddaloo]

Today's outlook: Feb15 AAE will be 4th lowest, Feb20 AAV will peak, Apr25 p1k (Piomas minus 1000) will be 2nd lowest, and Jun30 AAV will be 4th lowest.




[graph faq]

[viddaloo]

Icelook jan30: Average extent 4^th lowest in 18 days, average volume peaks in 21 days, p1k (Piomas minus 1000) will be 2^nd in 12 weeks, and average volume will be 4^th in 5 months.


[chart faq]

[viddaloo]

Icelook feb5: Average extent 6^th lowest in 8 weeks, average volume will be 6^th in 9 weeks, and p1k (Piomas minus 1000) will be 4^th in 24 days.


[chart faq]

[Peter Ellis]

Why has your forecast changed so radically in 5 days, and what do you think this implies for its reliability as a method?

[Peter Ellis]

Sure, but you're also using the same method to forecast a complete absence of ice year round in a few years' time.  The Met Office don't use their weather models to forecast more than a couple of days ahead.

[OSweetMrMath]

New monthly data for both PIOMAS and NSIDC extent is out, so I can update my predictions for the upcoming maximum.

My predicted value for the January monthly average volume from PIOMAS was 18.5 thousand cubic km. The actual value was 18.445 thousand cubic km. My prediction for April is slightly lower, at 24.0 thousand cubic km, with 95% confidence interval of 22.8 - 25.3 thousand cubic km.

My predicted value for the January monthly average extent from NSIDC was 13.8 million square km. The actual value was 13.62 million square km. My prediction for March is slightly lower, at 14.7 million square km, with 95% confidence interval of 14.1 - 15.4 million square km. I said last month that my prediction for January might be high, which turned out to be true, but not dramatically. I'm not aware of any current bias in the data which would be likely to make my current predictions off.

[Nightvid Cole]

Cryosat actually gets a LOWER volume for fall 2014 than it did for 2013:

http://www.esa.int/Our_Activities/Observing_the_Earth/CryoSat/CryoSat_extends_its_reach_on_the_Arctic

in stark contrast to PIOMAS.

[DavidR]

My prediction for March is slightly lower, at 14.7 million square km, with 95% confidence interval of 14.1 - 15.4 million square km.

I'm going to take a punt on 14.7 MKm^2 being  the maximum extent for this year, not the March average. The only area available for significant expansion now is the Northern Pacific and that  has been exceptionally warm for the last 8 months. The January average was the warmest this century. The Barents already is high in extent and area so that's probably not going to contribute a lot more either.

Of course strong winds could blow that estimate away.

[Michael Hauber]

There have been the odd comment on reduced Fram export being a big factor in the increased ice, and that Fram export has increased of late.

However I don't think that Fram export is the big issue, but rather the angle of the Transpolar Drift.  This appears to have shifted from a more Pacific - Atlantic angle towards being on a more Laptev - Canada angle.  The result is that more of the thick ice is being pushed into the Beaufort, and less towards NE Greenland.  The change in angle does tend to mean less ice being pushed into the Fram, but currently the wind direction in the Arctic is very much in the same Laptev - Canada direction, so even with faster Fram export the export would only be pulling thinner ice that came from the Laptev sector.

At the same time this change in transpolar drift has been encouraging a strong Laptev bite, which appeared to be at record size last summer, and indications from the Navy model are that the ice in that sector is even thinner than same time last year.  Ice free north pole for 2015 anyone?

[jdallen]

...
However I don't think that Fram export is the big issue, but rather the angle of the Transpolar Drift.  This appears to have shifted from a more Pacific - Atlantic angle towards being on a more Laptev - Canada angle.  The result is that more of the thick ice is being pushed into the Beaufort, and less towards NE Greenland...

At the same time this change in transpolar drift has been encouraging a strong Laptev bite, which appeared to be at record size last summer, and indications from the Navy model are that the ice in that sector is even thinner than same time last year.  ...

How funny... I spent several hours last night staring at the HYCOM Navy thickness models, comparing February 2014 with this year.

I have to agree, their projection doesn't look particularly promising - their estimates of ice thickness across the ESS and Laptev are nearly half a meter thinner than they were last year at the same time.

[viddaloo]

Icelook feb10: Average extent 6^th lowest in 8 weeks, average volume will be 6^th in 40 days, and p1k (Piomas minus 1000) will be 4^th in 11 days.


[chart faq]

[viddaloo]

2011 of course is tough competition — the toughest, in fact, in terms of average extent drop during the year — so it's really no surprise 2015 cannot keep up the fight. Instead we've seen in the 2 latest 'Icelooks' that 2015 has been chickening out and taking on 2014 as a more equal opponent. Sometime in early April we may be higher, and 2015 extent will change to light blue to reflect this fact.

For volume, of course, the situation is even worse, and the projected crossing of the 2008 graph on March 22nd will in less than a month thereafter take us into the pink territory of 7th lowest pinkness.

[OSweetMrMath]

I'm going to take a punt on 14.7 MKm^2 being  the maximum extent for this year, not the March average. The only area available for significant expansion now is the Northern Pacific and that  has been exceptionally warm for the last 8 months. The January average was the warmest this century. The Barents already is high in extent and area so that's probably not going to contribute a lot more either.

Of course strong winds could blow that estimate away.

Keep in mind that the daily extent is already nearly 14.3 Mkm^2. The monthly average runs well below the daily level during the freeze season.

[viddaloo]

Keep in mind that the daily extent is already nearly 14.3 Mkm^2. The monthly average runs well below the daily level during the freeze season.

Not in my book, sir. In it, extent hasn't been at 14.3 million since March 22nd 2014.

[jdallen]

IJIS on feb 10 shows extent at 13.8 million KM2

[crandles]

IJIS on feb 10 shows extent at 13.8 million KM2

Following the links up you will see OSMM and David R were talking about NSIDC extent which shows:

2015,    02,  07,   14.22251
2015,    02,  08,   14.35378
2015,    02,  09,   14.38811
2015,    02,  10,   14.41547

Personally I prefer area and at 12.819 is just 325k below 2011 record low maximum achieved 27 days after the 12.819 data. We gained over 325k over last 18 days but as the rate of gain would be expected to be lower near the maximum, a record low maximum area is not implausible at this stage. Normal level of noise around the top of the arc makes such a record this year unlikely, I think.

[DavidR]

IJIS on feb 10 shows extent at 13.8 million KM2

IJIS may be showing 13.8 but NSIDC (the measure we were referring to) is showing 14.4. Average extent increase from now to maximum ranges from 340 - 1000 K km^2 with an average under 500 for the past few years. My view is that we will be at the bottom of that range because of the relative warmth of the North Pacific.   

[viddaloo]

IJIS may be showing 13.8 but NSIDC (the measure we were referring to) is showing 14.4.

Interesting. What is their great dispute? What are the disputed territories?

[viddaloo]

While this isn't yet the melt season thread: An interesting development at the Pole. Animation of 7–11 February. From Uni–Bremen.

What's happening up there? Any theories?

At any rate HYCOM got it right. Many polynyas opening up in the CAB.

ro4co4 from Lance Modis.

Vergent

The above quote is from early June 2013. February is early for this sort of break–up, right?

Edit: Another Open-water-in-June quote from June 2014:

Ok, previous discussion about open water aside, what disturbs me most right now is summarized well in this image:

http://www.iup.uni-bremen.de:8084/amsr2/arctic_AMSR2_nic.png

In the quadrant between 80 N and 85N , between 150E and 165E, is an area of ice which is showing closer to 30% open water.

Considering that nothing lke that started showing up for closer to 30 days last year or the year before, I find that a bit disturbing.

I find that disturbing for two reasons.  First, I've found the DMI over all in two years of my following it, has tended to be more rather than less reliable. Second, it suggests profoundly unpleasant conclusions as to the state of the ice currently.

Add that to the various weather projections which have been getting discussed over the last week or so, it leads me to very pessimistic conclusions.

[Jim Hunt]

What's happening up there? Any theories?

What precisely is your point Vid? I've been following this sort of thing for quite a while now:

http://GreatWhiteCon.info/2014/09/santas-secret-summer-swimming-pool-revisited/

Winds blow. Ice moves. Satellites see "noise". Ask Wipneus!

https://forum.arctic-sea-ice.net/index.php/topic,382.msg45152.html#msg45152

Area actually decreased with the same rate, about 13k/day. Again the winds explain most of the changes

[Neven]

Vid, it could be that strong winds are causing (temporary) leads in a certain part of the Central Arctic during winter. It's also possible - and usually more probable - that the satellite sensor is thrown off by clouds or some glitch occurs. You see this a lot during Summer when large swathes of yellow, green and pink show up on the Uni Bremen sea ice concentration maps, only to disappear within a day or two.

Only when the different colours persistently stay in the same place for several days can you be sure there is open water (or a lot of melt ponds). Or at least, that's my interpretation of watching these UB SIC maps for several years now.

[viddaloo]

Yup. I know. That's why it's a 5–day vid.

[Neven]

In that case it could be leads opening because of the strong winds Wipneus mentioned in the AMSR2 thread:



This will probably increase the thickness/volume of the ice in that particular area (ridging, leads freezing over again).

[viddaloo]

What's happening up there? Any theories?

What precisely is your point Vid?

Allow me to expand a bit, as I've formulated my point rather short and clumsily:

By «What's happening up there?» I mean 'What is happening up there?'. Or with some added context: 'What do you people who frequent this forum believe may be happening up there?'.

Now, to the next sentence, I believe equally incomprehensible: «Any theories?». By that little enigma, I intend to request people who frequent this forum as to whether they have any ideas — not 'theories', strictly scientifically speaking — as to what may be 'happening up there' (see further explanation above).

In summary, I can see why you are confused. I should formulate more complete sentences where I also include some context to the questions. I should perhaps also explain that I would like people to answer said questions, they are not posed as 'statements' or any such thing, they are, in fact, questions, posed to the larger community, in hope of knowledgable answers.

[Jim Hunt]

[
By «What's happening up there?» I mean 'What is happening up there?'. Or with some added context: 'What do you people who frequent this forum believe may be happening up there?'.

Short but sweet? An old thread:

"Drift, Deformation and Fracture of Sea Ice"

[viddaloo]

"Drift, Deformation and Fracture of Sea Ice"

February is early for this sort of break–up, right?

[Jim Hunt]

A 2Mb vid for Vid:

[Edit - Now updated to February 17th]

[viddaloo]

I think... it on some level, is about fear.  I'll introduce my sumo wrestler metaphor here.

The "game" - net energy available in the environment - has been changing in more noticeable ways.  The weather is a symptom of that; the state of the ice is a symptom of that. 

We have already seen 6 months of absolutely extraordinary weather which has been very detrimental to the ice... to the degree that, in spite of a recovery last melt season, the ice at peak in April was no better off than at the start of 2012.  We have good reason to fear predictions of heat over the arctic.

Hyperbole aside, there are titanic forces at work energy-wise - my sumo wrestlers - and the mat has been progressively been tipping in favor of increasing melt.  One of these times, the "melt" wrestler will succeed in tossing his opponent off of the mat, this year, next, or whenever.  At some point the mat will tip so far in favor of melt, that any manner of supportive weather will fail, and we will see a catastrophic drop.

So, in view of that, I don't really find hyperbole that far out of place.  The way I look at it, it is just someone pointing out that this might be "it".

I find this analysis makes a lot of sense.

[Jim Hunt]

Some 3 Mb of SAR for Vid:

[jdallen]

My take-away is, over the last ten days or so, what we are seeing is the ice on the east side of the arctic reacting to the series of huge storms that raced north across the Atlantic to the Norwegian Sea after dumping upwards of 175CM (yes, that much) on parts of the eastern seaboard.

Coincidentally, they also pulled in train, huge amounts of moisture and heat from the ocean off of the U.S. coast.  SS Temperatures there are running as much as 8C above normal.  Some of that is what is keeping my parents snowed in in Scituate, MA.  They live about two blocks uphill from where CNN etc. were taking a bunch of the storm pictures they broadcast.

I wish we had a better sense of the snow over on the pack.  Increased precipitation is both a big positive heat transfer, and once down, inhibits ice formation.

(Further bit - that ice image looks rather "crunchy".  Lots of small interstitial leads rather than big ones? Or is it mostly/actually just differences in ice reflectivity?)

[viddaloo]

The above quotes from June 2013 and 2014 are instructive, and perhaps less conservative?

Many polynyas opening up in the CAB.

...an area of ice which is showing closer to 30% open water.

Considering that nothing like that started showing up for closer to 30 days last year or the year before [about July 1st 2013 and July 1st 2012, respectively], I find that a bit disturbing.

Considering it now shows up in February on very rotten ice, I find that extremely promising for a smashing melt season! 

[Jim Hunt]

Here's February 20th 2014, but what's a week or so between friends?

[jdallen]

Here's February 20th 2014, but what's a week or so between friends?

Very familiar; I'm more concerned about this year's weakness to the east and the ESS than the broken ice in 2014 NE of Svalbard.  I think that may be more crucial to the melt season, as it will have a more direct effect on MYI currently in the Beaufort and along the western extent of the CAA.

We may yet see an ice-free N pole in August.

[jdallen]

Cryosphere Today - 2/9/13 vs 2/9/15

In terms of extent, very similar at a gross level.

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=02&fd=09&fy=2013&sm=02&sd=09&sy=2015

[jdallen]

A bit of additional food for thought.

In four images, why I think significant additional thickening of the pack between now and mid April will be a serious up-hill climb for the arctic.

[viddaloo]

Some 3 Mb of SAR for Vid:

Reading both Danish and English I should be able to one day figure out what those pretty images are supposed to tell me about the ice, even though neither DMI nor ESA seem to have made any effort at explaining or guiding first–time users. I'm thinking it would be a terrible shame if all that expensive equipment and all that heavy data processing went down for years on end without any one human being on this planet being able to understand their end product plots or being willing to admit as much. For now I'm guessing the open water leads we are talking about are either dark, light or fifty shades of grey:



That's a pretty safe assumption, as that covers all of the info in the plot. I comfort myself with the knowledge that I now have some general idea about how heavy the satellites are, what programs they're taking part in, where in French Guiana they were launched from on what date and what scientific back history that kind of remote sensing has etc etc, the only thing I don't know the first thing about is how to interpret their main product, the ice maps. In other words the very first thing I myself would tell the end users if I was spending billions of their tax Euros in order to upload and distribute sea ice plots.

I find this amazing but intriguing. My long–term goal is to accidentally stumble upon a beginner's guide before I die. Then, of course, with a smile on my face! 

[nukefix]

I find this amazing but intriguing. My long–term goal is to accidentally stumble upon a beginner's guide before I die. Then, of course, with a smile on my face! 

Google is your friend

http://www.tos.org/oceanography/archive/26-2_dierking.pdf
http://www.sarusersmanual.com/ManualPDF/NOAASARManual_CH20_pg417-442.pdf

[viddaloo]

thx, nukefix! 

Icelook feb15: Average extent 6^th lowest in 30 days, average volume will be 6^th in 26 days, and p1k (Piomas minus 1000) will be 4^th in 5 days. The pendulum, in other words, is still swinging north. It may turn south during next week, but that's too early to tell yet. The implications of such a turn would be increasingly later dates for the estimated crossing from 5th to 6th lowest for both annual average volume and extent: They may be postponed back to April again. Volume may go light blue, but leave pink for the pre–2010 years. Refreeze is now slower than last year, has been for two days, that's why the pendulum is starting to slow down to zero.



[chart faq]

[viddaloo]

According to IJIS, this latest daily delta of –58225 km² was the biggest February melt since 2010. Also, my PIOMAS estimate algorithm reports the first ever February volume drop since 2007.

[Jim Hunt]

I've just updated my February 2015 AMSR2 animation. Scroll back or click here.

[Jim Hunt]

In associated news I arrive hotfoot from the ASIB where the latest "Shock News!" from the Arctic has just been reported:

IJIS Arctic Sea Ice Extent Lowest Ever!

[jdallen]

I've just updated my February 2015 AMSR2 animation....

It looks like the Atlantic side is pulsing to the frequency of storms rolling north along the US Eastern Seaboard and then onwards to the Barents.  No accident that, I expect.

[Jim Hunt]

It looks like the Atlantic side is pulsing to the frequency of storms rolling north along the US Eastern Seaboard and then onwards to the Barents.

I just made a YouTube video to help bring the shock news to the masses:



Please feel free to tell your friends.

[Jim Hunt]

Stop Press!!!

The NSIDC daily extent for February 17th has now been revealed to be 14,303,570  km², which is also their lowest ever reading for the day of the year (if my spreadsheet is to be believed at least).

[BornFromTheVoid]

With the daily extent for both NSIDC and IJIS now lowest on record for the time of year, we might expect a rebound to be on the horizon.
 
However, the outlook shows a strong ridges developing over western Russia and up into Alaska/western Canada, which could feed some milder air into the Arctic over the next 10 days. Somewhat similar to the very mild pattern we saw during much of last winter.

2 days out


4 days out


6 days out


8-10 days out