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Neven

The SIO has some more interesting info further down the page, which echoes what I have tried to convey in recent ASI updates:

The NSIDC time history for 2012 compared with previous years is shown in Figure 2. As noted in previous Sea Ice Outlook reports this year, sea ice extent in May started higher than several previous years and there were indications of increased thickness on the North American side. But late May and the first half of June had the Arctic Dipole (AD) Pressure pattern that is favorable for ice loss, resulting in a record trend in sea ice loss. At the end of June the AD was replaced by low sea level pressure. At this point, the sea ice loss showed more of a historical loss trend, but because of the low June value it has remained below the previous lowest value from 2007. The sea level pressure field for the second half of July and early August (Figure 3) shows that the low pressure centered along the dateline has persisted for most of the summer. This a a fairly typical historical summer pattern, if perhaps a bit stronger.

(...)

Except for early June, the weather was not particularly favorable for sea ice loss in summer 2012 as it was in 2007 and some other recent years. Given the lack of meteorological support and several indications that the sea ice was rather thin, we note that thermodynamic melting of thin, mobile sea ice is now a dominant process, justifying the low sea ice predictions in the Sea Ice Outlook.

Figure 3:

Neven

A tidbit on PIOMAS from the Lindsay/Zhang outlook:

In addition, the recently available IceBridge and helicopter-based electromagnetic (HEM) ice thickness quicklook data are assimilated into the initial 12-category sea ice thickness distribution fields in order to improve the initial conditions for the predictions.

What I'd love to know, is how much of these forecasts incorporated the effects of the recent cyclone.

crandles

The rules of the outlook contributions are that you use data up to 31 July only. So the answer should be not at all. (Even though it was well under way by the time the contributions are submitted and had been forecast for several days before that.)

I did throw in a mention of the cyclone which I don't take to be the same thing as using it to affect my statistical forecast. However, it is quite possible there is an effect on what forecasters do.

Neven

Thanks for that info, crandles!

BTW, if we combine the 4.24 million km2 from the ASI Blog poll with the 4.5 from WUWT, we get 4.37 million km2. Just above 2007.

Patrice Monroe Pustavrh

I have a problem with value of Bo Andersen. E.g. his value in pdf http://www.arcus.org/files/search/sea-ice-outlook/2012/08/pdf/pan-arctic/andersen.pdf he refers to his final values (He used Arctic Roos data) as 4.1 for Area and 5.6 for Extent. In text, he mentiones 2010 values. However, in prediction, it is mentioned that he predicts 4.1 for average extent. I am a little bit confused about that.

I Ballantinegray1

I voted in the NetWeather poll and certainly altered my original punt on receiving the heads up on the storm?

I'm sure folk who did not submit until the last moment also allowed for the damage they perceived the storm capable of? I'm sure none of us really got a handle on just how much damage the storm would do though? I'm still at a loss as to what the final account will be with the mixing and fragmentation?
to me it appeared to take all the 'at risk' ice but create a replacement for that fragile ice ready to melt out over the coming weeks?

Alberto Silva

WUWT predicting a minimum below 2007?

Wow, even the deniers are melting now that reality has hit them in their faces, ...

there is still hope for this planet and all its inhabitants!

Artful Dodger

Hi Alberto,

The WTFUP 2012 predilection is 4.5 while 2007 NSIDC monthly avg was 4.3 so your skepticism is restored.

Cheers,
Lodger

Charles Longway

Neven,
Still off topic from last week, but hidden in a shorter thread to avoid damaging the signal of the blog.
Please open a separate thread for discussion on actions. What we saw last week needs a response. Last year, in response to your denial critics, you said ‘the ice will protect me’ - and so it has. Now we need to protect the ice. People who come to know what we have learned of the arctic will do something to help. I think that we can be trusted to maintain the standard of excellence established in technical threads. Perhaps a single exploratory thread could test the water.

NeilT

If I recall correctly, when WUWT were doing their song and dance about the super ice growth in the Arctic, they were forecasting 5.5m or 5.6m on SEARCH

NeilT

Hit post without meaning to...

Should we not use this inconsistency to beat WUWT into silence every time they pop up???

Wipneus

Neven:

These projections are submitted by professionals as well as amateurs, such as our own Chris Randles and Larry Hamilton

You can add me to the list, second lowest: 4.0 +/- 0.7 10^6 km2

Steve Bloom

NeilT, the basic technique there is "lying and exaggerating for effect," so while they can be ridiculed it's unlikely they'll shut up.

Regarding WUWT, though, and speaking as someone who compulsively adds to their traffic count once a day because... must... watch... train... wreck, I have the impression that the tone there has been goosed somewhat in response to declining traffic. Tony's recent crash-and-burn on his so-called "paper" is more evidence to that effect.

Espen Olsen

Healy is where the "steamy" ice is, have a look :

http://icefloe.net/Aloftcon_Photos/index.php?album=2012&image=20120814-0501.jpeg

crandles

Hi Wipneus, nice to see you contributing. :-)

You wrote "A least squared regression yields a value of 3.98 +/-0.67 million km2". Does that mean the +/-0.67 does not take account of any uncertainty in the volume estimate?

I doubt that volume uncertainty remains much. At end of July we were 0.73 K Km^3 below last year but the cyclone is likely to have increased that difference. Working from latest volume data like this presumably reduces the volume uncertainty compared to just jusing volume projection from September minimum data.

Wipneus

crandles:

Does that mean the +/-0.67 does not take account of any uncertainty in the volume estimate?

I ignored it. The uncertainty from volume would be about 0.2 10^6 km2. Combining the two independent errors would result in 0.70 10^6 km2.

John Christensen

I have been mostly absent for the summer during this terrible loss of sea ice in the Arctic.

However, I cannot help noticing that the SIA summer minimums for '07, '08, '10, and '11 have all bottomed out around 3 10^6 km2.

This would seem logical in the sense that in early summer we have all factors working in unison to melt the ice: Sun radiation, increased backfeed radiation, warmer sea currents, and increased storms.

Howevery, could the flattening trend be an indication that at least now the decrease in direct sun radiation and related decrease in feedback even the score, so that the warm water still is thinning the ice, but the area remains somewhat intact?

Not many on this blog can be of that opinion, as I noticed that 81% believe that CT SIA will go below 2.8 10^6 km2.. (I have stayed in the 3.7% voting for a minimum of 2.9-3.0 10^6 km2).

I would see this as similar to the late winter high CT SIA numbers in recent years: The water is warmer, so will freeze later, but spring melting will only set in, when the sun is high enough in the sky, so there would be no reason for early spring melting to accelerate.

Comments?

John Christensen

'Early spring' being mid-March-mid-April..

DrTskoul

John,

You mean the famous "fat arse". This is partially true. You will probably have noticed that the beginning of the "fat arse" is earlier this year than others. There is a distinct probability that this the area will not go much lower than prior years. However, the ice cannot continue thining without showing in the area and extent metrics. Other people here (crandles, Chris "dosbat" Reynolds, Chris "torcher" Biscan) have noticed that and wondered when will the year be that the area/extent crashes. Maybe it is this year (and the storm has made sure that the probability goes up), maybe next year. Who knows. However, all metrics/statistics/empirical evidence, give a rather high probability that area will reduce lower than 2007/2011. The only thing we can do is watch, wait, and test our hypotheses against the real world. If we miss something that's good, we will learn something new. That's what the models do too, you put as much physics as you think is right, make a prediction, validate/invalidate, correct and go again at it. Healthy scientific approach...

DrTskoul

Has UNI Bremen hit a record already? At least the graph shows as much....Maybe I am crosseyed

DrTskoul

And let the compaction start!!

John Christensen

I agree; we are hovering just above 3 10^6 km2 about 10 days earlier than in 2007 and 2012, so it seems this year will be a good test of just how solid this bottom really is..

crandles

>" (I have stayed in the 3.7% voting for a minimum of 2.9-3.0 10^6 km2)."

Are you aware and considered that the smallest decline from 11 Aug (last data 3.113) to minimum is 0.28. So if we are luckly enough to get decline that is only equal lowest, then that puts minimum at 2.83.

As the area has been low during the past couple of months then the ocean should have absorbed a lot of heat and there should be a strong bottom melt season? Perhaps the holy nature of the pack means lots of heat was absorbed but efficiently used already in bottom melt to get the area down to what it is now?

Espen Olsen

Oden North of Greenland +/- 84 N:

A new sub "mountain" is discovered near The Lomonosov Ridge, it is about 1000 meter:

http://www.sjofartsverket.se/pages/39700/Multibeam.jpeg

Report from Oden:
http://www.sjofartsverket.se/sv/Sjofartssektorn/Sjofartsforskning/Polarexpeditioner-med-isbrytaren-Oden/LOMROG-III/8-augusti-20121/

Seke Rob

CT-SIA [to be clear on what is broached on] latest chart updates with a minimum projection line creeping up:

With how much still to melt in prior years from today: http://bit.ly/CTNHM2

The simpler version, with just the projection line and how much 2012 has already passed prior years [and how much still to go to pass the last 4 prior year minima that were lower than present day: http://bit.ly/CTNHMn

-30K km^2 needed to pass 2010. My worst case present possible minimum 2.64. No matter what all those FS visionaries, lower or higher than any previous record is at this time pretty much academic. The overall state of the Arctic: cow dung.

Kris

DrTskoul wondered:

Has UNI Bremen hit a record already?

First of all, UNI-Bremen has had corrected it's minima for 2007 and 2011, uplifting the values to about 4,6 millions km².

According to todays UNI-Bremen chart the record should be tied indeed, solely to UNI-Bremen standards of course.

OTOH, Arctic SIE according to IARC-JAXA
should be at 5.020.313 km2 on 15th of August.

Even taken into consideration the 15th of August Tokyo time might be midday 14th in Europe, 400.000 km² of difference comes a bit over as disturbing.

Well, what's in a record?

Artful Dodger

Over the past two days, UniHamburg KlimaCampus's (Beitsch et al) live SIO outlook has gone stark raving bonkers:

The September mean NSIDC SIE estimate updated on Aug 27 has dropped to 0.6 M km^2.

Project FTP folder, updated daily @ around 7:30 CET

Open the file "estimate.png" for the daily updated prediction of Sep avg SIE. Clearly, this is NOT your father's Arctic.

Seke Rob

... and +/- 0.1 M km^2 margin of error at that... well they could not put it at 0.6 of course: "stark, raving, bonkers", just a case of Nurse Ratched having botched a left-handed lobotomy [the expert was out :].

FrankD

Lodger,

The anomaly.png in that folder appears to be blank. On the assumption that the concentration data is used in their prediction model, I suspect they might have fed a zero into their calcs, causing it to...well, politeness forbids...

johnm33

Just when i was beggining to think i was a pessimist.
I was wondering if the typhoon down by japan would track north and found this
http://www.esrl.noaa.gov/psd/map/images/ens/allmaps_f048_nh.html
which i can't understand, here
http://www.esrl.noaa.gov/psd/map/images/ens/ens.html#nh
on
http://www.weathercharts.org/

Artful Dodger

Hi Frank,

Yeah, it's a funny correlation they've discovered (and they use for their estimate). They calculate the area of sea ice in one square in the Central Basin on the North edge of the Beaufort Sea, and divide that by another area to the NE of Greenland.

Funny, the Beaufort sea ice all gone, and eatin' into the Central Basin now...

All the old rules are obsolete now. This is not your father's Arctic

Cheers,
Lodger

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