IJIS

[OldLeatherneck]

Due to todays number from IJIS we are now having a minimum at a guaranteed third place as 2011 minimum was eclipsed by 1154 km². I think we can rule out the possibility of beating 2007.

I'll be dipped. I thought it was done. Guess the season had a few more dents to cause before it stopped bouncing.

A week ago, I was dead certain that 2015 would go below 2011's annual minimum. Two or three days ago, I was almost equally certain that 2011 no longer had any chance of eclipsing 2011.  It is almost impossible to predict what will happen in mid-September when the re-freezing forces are competing with the melting forces for dominance.  Will 2015 have any more significant losses in the next four or five days.

[Espen]

Due to todays number from IJIS we are now having a minimum at a guaranteed third place as 2011 minimum was eclipsed by 1154 km². I think we can rule out the possibility of beating 2007.

I'll be dipped. I thought it was done. Guess the season had a few more dents to cause before it stopped bouncing.

A week ago, I was dead certain that 2015 would go below 2011's annual minimum. Two or three days ago, I was almost equally certain that 2011 no longer had any chance of eclipsing 2011.  It is almost impossible to predict what will happen in mid-September when the re-freezing forces are competing with the melting forces for dominance.  Will 2015 have any more significant losses in the next four or five days.

[jdallen]

Due to todays number from IJIS we are now having a minimum at a guaranteed third place as 2011 minimum was eclipsed by 1154 km². I think we can rule out the possibility of beating 2007.

I'll be dipped. I thought it was done. Guess the season had a few more dents to cause before it stopped bouncing.

A week ago, I was dead certain that 2015 would go below 2011's annual minimum. Two or three days ago, I was almost equally certain that 2011 no longer had any chance of eclipsing 2011.  It is almost impossible to predict what will happen in mid-September when the re-freezing forces are competing with the melting forces for dominance.  Will 2015 have any more significant losses in the next four or five days.

<insert amused laughter here>

Yes, absurdly volatile.  Now that it's back down to a virtual tie with 2011, two more drops like the last one plus a little extra take us to 2007.

It's at the whim of the weather, and impossible to call for at least another week, if not more.

(Edit/PS: noted elsewhere, this year reached its record by brute forcing of heat. There hasn't been any export to speak of through the Fram for months, Nares is stalled, and the Beaufort gyre has been anemic. Reports from the Healy < or was it Polarstern?> indicate vast stretches of the Arctic north of 80 are covered with ice so rotten it is unsafe to stand on. In view of that, I'm not sure the current numbers prove we are better off than we were in 2012.)

[magnamentis]

@jdallen your thought go into the right direction IMO. the next big drop ( and it will be a drop i'm sure ) will come again as a surprise of course, or did anyone expect 2007 or 2012 to happen what happened. looking at the predicted wind pattern in about 4-5 days i'd say if that becomes true that relatively warm air will run over the entire eastern part of the arctic at relatively high speeds and over hundreds if not thousands of km and consider the wave building that can be expected and all the mixing with warmer waters from the depth, such a surprise is still possible, be it a relative late low in extent as well as 2-3 days of relative steep losses. must not be, who knows but i repeat myself by saying that there is a huge amount of energy in the system that sooner or later will surprise us. to some extent this entire year was a succession of surprises, be it early max, relative low max, summer temps, strangely persistent ice way south ( hudson etc. ) and still at the end we were always ending at the lower end or below what has been predicted.

[Espen]

IJIS:

4,257,003 km²（September 14, 2015）down 11,042 km² from previous.

[seaicesailor]

...this year reached its record by brute forcing of heat. There hasn't been any export to speak of through the Fram for months, Nares is stalled, and the Beaufort gyre has been anemic.

Spot on. The NH is very warm, record hot, and this year there has been a lot of transfer of this heat, from Winter to Summer. Should we get this plus export, we can see how a 1 million km2 min extent season can be. Not good.

[Espen]

IJIS:

4,359,080 km²（September 15, 2015）up 102,077 km² from previous.

[oren]

T H E   E N D

[Espen]

IJIS:

4,391,720 km²（September 16, 2015）up 32,640 km² from previous.

[Espen]

IJIS:

4,412,057 km²（September 17, 2015）up 20,337 km² from previous.

[CraigsIsland]

...this year reached its record by brute forcing of heat. There hasn't been any export to speak of through the Fram for months, Nares is stalled, and the Beaufort gyre has been anemic.

Spot on. The NH is very warm, record hot, and this year there has been a lot of transfer of this heat, from Winter to Summer. Should we get this plus export, we can see how a 1 million km2 min extent season can be. Not good.

100% agreed.

We got lucky this year- less Fram export but a lot of other variables doesn't make this season any better than years' past!

[jdallen]

...this year reached its record by brute forcing of heat. There hasn't been any export to speak of through the Fram for months, Nares is stalled, and the Beaufort gyre has been anemic.

Spot on. The NH is very warm, record hot, and this year there has been a lot of transfer of this heat, from Winter to Summer. Should we get this plus export, we can see how a 1 million km2 min extent season can be. Not good.

100% agreed.

We got lucky this year- less Fram export but a lot of other variables doesn't make this season any better than years' past!

My understanding is, typical Fram export in past years ranged from 5-10,000 KM2/day.  If we had had Fram export, this year we would have blown past 2007 by a very wide margin - several hundred thousand KM2 - and at the higher end, flirted with 2012.

[Espen]

It is a new regime Fram is dead

[Espen]

IJIS:

4,502,176 km²（September 18, 2015）up 90,119 km² from previous.

[Espen]

2015 must be the year with the smallest amount of Sea Ice below 75?

[Espen]

IJIS:

4,558,903 km²（September 19, 2015）up 57,727 km² from previous.

[Espen]

IJIS:

4,592,293 km2（September 20, 2015）up 33,390 km2 from previous.

[Espen]

IJIS:

4,592,870 km²（September 21, 2015）up 577 km² from previous.

[Espen]

IJIS:

4,627,917 km²（September 22, 2015）up 35,047 km² from previous.

[Espen]

IJIS:

4,704,361 km²（September 23, 2015）up 76,444 km² from previous.

[Espen]

IJIS:

4,755,283 km²（September 24, 2015）up 50,922 km² from previous.

[Espen]

IJIS:

4,758,781 km²（September 25, 2015）up 3,543 km² from previous.

[Espen]

IJIS:

4,737,804 km²（September 26, 2015）down 20,977 km² from previous.

[Lennart van der Linde]

For the record: it seems 1000 km2 got lost somewhere...

[jdallen]

IJIS:

4,737,804 km²（September 26, 2015）down 20,977 km² from previous.

The current behavior of the numbers seems to me to be consistent with the CAB rapidly icing back up followed by a much slower battle between the residual summer heat in peripheral seas and and the expanding edges of the ice.

[Espen]

IJIS:

4,800,485 km²（September 27, 2015）up 62,681 km² from previous.

[Espen]

IJIS:

 4,881,060 km²（September 28, 2015）up 80,575 km² from previous.

[Espen]

IJIS:

4,968,229 km²（September 29, 2015）up 87,169 km² from previous.

[Espen]

IJIS:

5,033,109 km²（September 30, 2015）up 64,880 km² from previous.

[Espen]

IJIS:

5,069,941 km²（October 1, 2015）up 36,832 km² from previous.

[Espen]

IJIS:

5,053,825 km²（October 2, 2015）down 16,116 km² from previous.

[Tor Bejnar]

Continuing this (daily) rate, 2015 will be in 1st place within a fortnight! 

[Espen]

IJIS:

5,100,042 km²（October 3, 2015）up 46,217 km² from previous.

[Espen]

IJIS:

5,179,899 km²（October 4, 2015）up 79,857 km² from previous.

[Espen]

IJIS:

5,315,653 km²（October 5, 2015）up 135,754 km² from previous.

[Espen]

IJIS:

5,463,199 km²（October 6, 2015）up 147,546 km² from previous.

[Espen]

IJIS:

5,607,279 km²（October 7, 2015）up 144,080 km² from previous.

[Espen]

IJIS:

5,754,297 km²（October 8, 2015）up 147,018 km² from previous.

[jdallen]

IJIS:

5,754,297 km²（October 8, 2015）up 147,018 km² from previous.

I am fascinated by how fast extent is rocketing up, as compared to 2007, 2011 and 2012.  I'm as yet at a complete loss to understand how it's happening, and what it implies about the heat exchange that is taking place.

[kingbum]

IJIS:

5,754,297 km²（October 8, 2015）up 147,018 km² from previous.

I am fascinated by how fast extent is rocketing up, as compared to 2007, 2011 and 2012.  I'm as yet at a complete loss to understand how it's happening, and what it implies about the heat exchange that is taking place.

My suspicion is that the ozone levels are low allowing heat to be lost through a hole or weakness but I don't have any hard numbers to back that up yet

[jdallen]

IJIS:

5,754,297 km²（October 8, 2015）up 147,018 km² from previous.

I am fascinated by how fast extent is rocketing up, as compared to 2007, 2011 and 2012.  I'm as yet at a complete loss to understand how it's happening, and what it implies about the heat exchange that is taking place.

My suspicion is that the ozone levels are low allowing heat to be lost through a hole or weakness but I don't have any hard numbers to back that up yet

That would be kind of a stretch, as the heat can only leave as fast as it's radiated, which is directly dependent on the reservoir of heat at the surface, which is locked pretty solidly at around 270K or so.

As I think about it, I'm wondering if the rapid increases are due to precipitation.  My hypothesis is, increased precipitation has produced snowfall, which on falling into water which is below 0C, is providing moderately substantial base for prompt freezing at the surface.  I'll be looking for evidence to support or refute this.

[Espen]

IJIS:

5,893,819 km²（October 9, 2015）up 139,522 km² from previous.

[Quantum]

IJIS:

5,754,297 km²（October 8, 2015）up 147,018 km² from previous.

I am fascinated by how fast extent is rocketing up, as compared to 2007, 2011 and 2012.  I'm as yet at a complete loss to understand how it's happening, and what it implies about the heat exchange that is taking place.

My suspicion is that the ozone levels are low allowing heat to be lost through a hole or weakness but I don't have any hard numbers to back that up yet

I might be completely wrong but I suspect the explanation is much simpler. In the laptev and the beaufort there was some ice rubble left from the melt season. This rubble was multi-year but had such a low concentration even on the AMSR2 it was not visible (before being covered by new ice). However if you have a look at the MASIE archive charts you can see the ice remants in both the beaufort and the laptev here:

ftp://sidads.colorado.edu/DATASETS/NOAA/G02186/latest/4km/

Compare the speed of refreeze in the laptev with the east siberian. Both show new ice towards the coast, but the laptev refreeze dominates completely. Also notice how there is still open water well into the bay in the laptev which is counter-intuitive. However no ice survived in that bay. Any remaining ice rubble no matter how small (and it was small) will guarantee the temperature of the surrounding water is at freezing point, so the process should be much quicker than expected. If ice rubble survives in the Hudson we may see a similar process later (although it looks unlikely)

[jdallen]

IJIS:

5,754,297 km²（October 8, 2015）up 147,018 km² from previous.

I am fascinated by how fast extent is rocketing up, as compared to 2007, 2011 and 2012.  I'm as yet at a complete loss to understand how it's happening, and what it implies about the heat exchange that is taking place.

My suspicion is that the ozone levels are low allowing heat to be lost through a hole or weakness but I don't have any hard numbers to back that up yet

I might be completely wrong but I suspect the explanation is much simpler. In the laptev and the beaufort there was some ice rubble left from the melt season. This rubble was multi-year but had such a low concentration even on the AMSR2 it was not visible (before being covered by new ice). However if you have a look at the MASIE archive charts you can see the ice remants in both the beaufort and the laptev here:

ftp://sidads.colorado.edu/DATASETS/NOAA/G02186/latest/4km/

Compare the speed of refreeze in the laptev with the east siberian. Both show new ice towards the coast, but the laptev refreeze dominates completely. Also notice how there is still open water well into the bay in the laptev which is counter-intuitive. However no ice survived in that bay. Any remaining ice rubble no matter how small (and it was small) will guarantee the temperature of the surrounding water is at freezing point, so the process should be much quicker than expected. If ice rubble survives in the Hudson we may see a similar process later (although it looks unlikely)

Your observation has merit.  More information gathering is indicated.

For my point, my thinking was that snow in the water would provide nucleation for rapid freezing. 

More of it, due to higher humidity, could form plaques quite rapidly, in time frames on the order of hours.  In this lies an interesting twist to the heat transfer.  The freezing takes place via transfer of energy out of the atmosphere rather than out of the water.

Now the heat that produced the moisture may have come from arctic seas, so it may still represent net transfer out of them, but it seems trying to track the movement of heat has become more complex than ever.

[Espen]

IJIS:

5,975,898 km²（October 10, 2015）up 81,979 km² from previous.

[werther]

JDAllen, hi,
to form an opinion on your remarks on rapid extent growth, I checked some NCEP/NCAR data.
Above is 1000Mb Temp anomaly for 1-7 October. It is much above FI same period 2011. DMI by the way shows the same. My guess is last week was the timeframe for massive heat release in the peripheral seas around the CAB.
Pressure pattern looks right for the refreeze pattern suggested by Quantum. Looking at MODIS, a lot of the refreeze in the Chukchi sector is nilas and pancake ice. Nothing strong yet, simply because mean temps aren’t low enough.

[jdallen]

JDAllen, hi,
to form an opinion on your remarks on rapid extent growth, I checked some NCEP/NCAR data.
Above is 1000Mb Temp anomaly for 1-7 October. It is much above FI same period 2011. DMI by the way shows the same. My guess is last week was the timeframe for massive heat release in the peripheral seas around the CAB.
Pressure pattern looks right for the refreeze pattern suggested by Quantum. Looking at MODIS, a lot of the refreeze in the Chukchi sector is nilas and pancake ice. Nothing strong yet, simply because mean temps aren’t low enough.

That fits generally with my thinking as an alternative to precipitation based expansion of SIA/SIE.  Are we sure the temperature anomaly is driven by local oceanic release, or imported heat?

[werther]

Am I sure? Ah, don't know. Some particulars about the pressure pattern, on sea level as well as on 500Mb, make me wonder whether there's a teleconnection. As the troposphere in the Walker Cell is responding to the accelerating ENSO event, who knows? I used to struggle on the Rossby Wave pattern and the height of the troposphere/500Mb level. I suppose both enhance poleward transport of heat. I haven't done much work on that of late. Nevertheless, I propose that current behaviour in the Pacific Basin fit right into the story.
If so, part of the current heat pulse over the Arctic Ocean is driven by accumulated heat released into the polar night. But part of it could relate to heat transfer from the Pacific. A strong El Nino might have unforeseen effects.

[Espen]

IJIS:

 6,037,585 km²（October 11, 2015）up 61,687 km² from previous.

[Espen]

IJIS:

6,127,490 km²（October 12, 2015）up 89,905 km² from previous.