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Tor Bejnar

The years go by fast, but it looked like substantially ice-free (< 1million sq. km.) would first appear about 2020, per the animation. (I'm making the assumption that the 30-days open water divide is the equivalent.)

Susan Anderson

Terrific animation, thank you. I've been hot on the case of that Antarctic thing (see below), and this neat NYTimes Magazine (worth one of monthly 10 free visits) features especially Eric Rignot, who is bothered about it. There was that amazing Greenland feature a couple weeks back as well, but I will only include the recent link:
http://www.nytimes.com/2015/11/15/magazine/the-secrets-in-greenlands-ice-sheets.html

For a shortcut on the Zwally here's a borrowed extract:

This study stopped at 2008, so recent information was not included.
http://arstechnica.com/science/2015/11/study-concludes-antarctica-is-gai...

Another scientist (and more at the link):

Eric Rignot, who has worked on similar Antarctic studies, has been fielding a lot of questions about this one ... “I am afraid I have some rather harsh words about it,” he wrote. Rignot said the data just aren’t precise enough to support the paper's conclusions.

“Zwally's group is the only one pushing its interpretation beyond the realm of the inherent uncertainty of the data. Accumulation of snow in East Antarctica is 10 centimeters water equivalent per year. To detect changes in accumulation of 136 gigatons (with no error bar), or 10 percent, Zwally et al. needs to detect changes of the order of 1 centimeter. Current technology such as ICESat cannot detect any change smaller than 20 centimeters. Radar altimetry (used for the earlier period) is closer to 40-50 centimeter noise, but nobody really knows. There is no way to detect changes in East Antarctic accumulation at the 10 percent level, not even 50 percent level, with those kinds of error bars,” ...

“The Zwally group’s findings are at odds with all other independent methods: re-analysis, gravity measurements, mass budget method, and other groups using the same data.”

Chris Reynolds

Thanks Neven, very sobering.

Hans Gunnstaddar

Would be nice if animation could be controlled, i.e. slowed down or stopped at certain years, but very illuminating none the less.

If there is good predictive data on arctic methane emissions, it would add a lot to see the increase in those emissions added as an orange mist.

AbbottisGone

http://nsidc.org/arcticseaicenews/files/2015/11/Figure4a_.png

Where has all the multi-year ice gone?

AbbottisGone

https://robertscribbler.files.wordpress.com/2015/11/november-16-temperature-departures.jpg?w=600&h=493

Thought Perth had been a bit hot lately!!

P-maker

AbbottisGone,

it "Melted From the Bottom, now it's gone!"

See also: https://www.youtube.com/watch?v=RubBzkZzpUA

As you will see in the video (around 0:20 ), there is plenty of snow up there, so it must be darn cold. Hence, it can only be bottom melt at this time of the year...

John Christensen

P-maker,

I was amazed by the crevasse - though it did not look very cold..

John Christensen

Abbottisgone,

The Cryosat image does not look very accurate and seems to ignore the areas of thicker ice. Also, the star shape of the ice seems to be erroneous.

The US Navy and DMI have thickness charts that resemble each other reasonably well (DMI with more generous estimates than hycom):

http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictn_nowcast_anim30d.gif

http://ocean.dmi.dk/anim/index.uk.php

P-maker

Dear John,

please accept todays' first English lesson:

It's called cleavage, if your are referring to that pretty young woman in the video.

It's called a crevasse, if you are on a glacier.

On Arctic sea ice, we call it leads. Leads may lead anywhere, but they hardly help getting rid of multi-year ice at this time of year.

Bill Fothergill

@ P-maker

cleavage/crevasse tee-hee

I live about 100 metres from a pub called the Cleave - named after a well-known nearby geological feature. During the Millennium celebrations, a former Bond-girl who lives nearby was serving ale, and the pub consequently - but temporarily - changed its name to "the Cleavage".

Moving swiftly on the subject title of this post: - Following hard on the heels of the record breaking October temperature anomaly posted by UAH, Gistemp has just posted its first - but it won't be its last -anomaly that is in excess of 1 degree C.

"Pause" for thought?

John Christensen

I was merely trying to make a glaciological reference, so that my note would go undetected by Neven, but I am sure that is ruined by now.. ;-)

I probably should have used 'gorge' or 'couloir' - the French have great words..

AbbottisGone

..all I'm saying is I live in Perth, WA(yes, one of those mega-hotspots found on the second graphic I posted from the blogroll given on this site) and we haven't had a record temp. in the last few days for November but pretty close enough for us all to exchange raised eyebrows at every social exchange if you catch my drift...

AbbottisGone

The temperature hit 39.4 degrees shortly before noon, less than a degree shy of the 40.3-degree record set in 1913 and again in 2003.

Read more: http://www.watoday.com.au/wa-news/busy-perth-to-bake-in-38-degree-scorcher-20151114-gkyyw8.html#ixzz3rnfdD0qq

EconDemocracySV

Here's how to slow down the image, use the tool at http://ezgif.com/speed

I find the image already striking, almost scary..but I agree with the earlier comment that the years fly by so thought I'd share this gif speed changing tool so others can use. -EconDemocracy

Kris

In accordance with the ADS-NIPR standards, yesterday 18 Novembre 2015 [9,0 km²] just dived under 18 Novembre 2007 [9,4 km²]

Tor Bejnar

Unfortunately, the gif is 256MB in size and http://ezgif.com/speed requires a gif to be 16MB or smaller. It slows down 1990 and 1991 very nicely!
I managed to get screen shots of 2012 and 2019-31. 2030 looks vaguely like the 30-days-per-year area is half the 2012 area. They are posted on the forum at http://forum.arctic-sea-ice.net/index.php/topic,1112.0.html (post #1064).

Bill Fothergill

@ Kris

A slight typo there.

The Nov 18 value for 2007 was approx* 9.64 million sq kms as against 9.6 million sq kms for the same date this year. (* For whatever reason, I can't open the CSV in order to get the more precise value stored therein.)

Kris

Bill Fothergill wrote:

A slight typo there

Even worse, bad a calculation. Looks like Saturn [The Bringer of old Age] has hit me severely.

Saturn must be responsible too for the forgotten remark, namely there has been a small downtick yesterday. Albeit we can't assume the melting season already would have started, can we?

Neven
Albeit we can't assume the melting season already would have started, can we?

No, let's not assume that. :-P

But, as alluded to in the previous blog post, the (very) positive AO has resulted in an ice growth hiatus, just like it did in 2013 (though less pronounced).

Kris

... and a downtick again at ADS-BIPR, [defying Saturn] minus 0,013422 km² yesterday. And so 2015 is closing in to 2012 now.

Insomma, despite the record lows in Alaska, the gain on the Bering Sea side can't compensate for the losses at the Barents Sea side and Hudson Bay. Incidentally, according the the Climate Reorganiser Alaska is heading again to another "heat wave" next week ...

AbbottisGone

Is sea ice thickness abnormal for this time of year?

Neven

Compared to what? What dataset?

AbbottisGone

@ John,

I must have missed your links days ago sorry:

They are projections, yes? The multi-year ice would seem to be fine according to them, yes?

AbbottisGone

"Compared to what data-sets?": all of them in relative speaking I suppose.

I have to go but will get back... stoked you answered in-between my posts, cheers!

EconDemocracySV

Tor,
I right-clicked on the image, chose "view image" on firefox, and then saved to my desktop; the size is 2.7MB for me, not 256MB. Just tried a direct right-click-to-save in case anything strange, got same 2.7 MB size.

Is there a larger size elsewhere? If so, just use this 2.7MB instead, and then you can slow down the whole thing I suspect. (Btw how do you ask for email notifications of replies to comments here?)


@Tor

Neven

The original was 3.2 MB, which makes the page load slow for some people, so I tried to make it smaller, but didn't get it lower than 2.7 MB.

Btw how do you ask for email notifications of replies to comments here?

Unfortunately, I don't believe there is such a function, like there is in Wordpress and Blogger, which is really handy.

Tim

WRT to reducing your carbon footprint: Americans who want to install residential solar PV systems should take note that 2016 is the last year for which the 30% residential tax credit is guaranteed. Installers will be working on my 6.2 kW capacity system tomorrow. I live in a fairly favorable location for solar (College Station, TX - good latitude, but number of cloudy days is greater than east TX, New Mexico, Arizona, or So. Cal. If you live in Phoenix or San Diego and can possibly afford to do this, it is a financial no-brainer - far better than any low-risk long term investment you can find.

Tor Bejnar

Thanks, EconDemocracySV for the guidance. I copied the GIF from Neven's post to my computer (iMac): not only was it 2.7 MB, but the individual year images were right there to view!
(Whether I paste the copied file or input the link into the GIF speed changer, it downloads it as a very large GIF and only shows a slowed down 1920 and 1921, [not '90-91 as I previously reported - I'd just had surgery and was under the influence ...].)

AbbottisGone

Dear Tim,
Look at 14min19sec of this video: https://www.youtube.com/watch?v=FQhKDrJ0DFw

"Ya gotta think big!" (Classic/ Rolled Gold: Did Trump inspire or copy we all wonder in unison, lolol!!)

A-Team

The animation consists of 181 frames. To keep the file size down, the authors saved in 'optimize' gif mode, which means two things: first, only the (very small) change between successive frames is saved in the later frame. The lossless LZW compression used clobbers the blank areas of these change-only frames.

Second, to make the optimized animation play smoothly, it's been incorrectly defaulted to 0 milliseconds delay between frames so it will play as fast as your CPU will allow and fool the eye with the gutted out intermediate frames. This is a bug in the gif standard as it can totally hog a visitor's CPU as it loops. The option is over-ridden in good animation software which will require a minimum frame delay of 10 ms or more.

You can de-optimize the animation with a single Gimp command, or on a mac simply view in Preview which does this by default (for capturing a frame or two of interest).

Scientific journals do not use animated gifs so much but more commonly .mov which don't run on their own but have a slider that allows you rapid back and forth.

The original GIF89a spec doesn't loop. A loop counter was added later by Netscape Navigator 2.0 though most animated gif loop indefinitely. You can still set the loop count in ImageJ but Gimp only offers once or indefinite.

The gif spec really needs to be fixed. It would not be rocket science to add a speed controller and step-through/save frames for viewers.

AbbottisGone

The latest sea ice extent figures for the Arctic seem to be flatlining...does anyone know why?

Neven

AiG, my hunch is that it's because of low pressure areas dominating the Arctic (expressed by a highly positive Arctic Oscillation that had the same effect in November 2013) keeping the cold in the centre of the Arctic and winds pushing the ice inwards at the edges (for instance on the Atlantic side of the Arctic where there's a lot of room for expansion).

This doesn't mean all that much in itself. A lack of expansion might well mean the core is getting thicker. And the effects of a positive AO may be different from January onwards, etc.

But that is what I think is causing the hiatus, I mean the slowdown in growth. But growth will resume at a pace similar to the average, either soon or a few weeks from now.

Bill Fothergill

@AiG

If you want to see a real slowdown* in growth at about this time of year, take a look at the 2006 figures. (*I now try to avoid using the terms "hiatus" or "pause", as these have been suborned for nefarious purposes - or is that some kind of dolphin????)

I know it's too soon to be significant yet, but, over the last 4-5 days, there is a divergence developing between the ADS and NSIDC regrowth rates. It will be interesting to see how that pans out.

John Christensen

Regarding the lack of growth of Arctic ice these past days, I would not put the positive AO as a reason, but rather as a consequence of the primary reason.

The AO is closely interlinked with the jet stream, but what is currently causing the strong winds from west to east along the Siberian north coast is the unusually early and strong cold in Siberia.
As you see on weather maps the jet stream moves south of the Siberian cold, so the winds are caused by the Siberian high and not the jet stream.
It is then correct that the Arctic Ocean is dominated by low pressures countering the Siberian high and it would seem like this situation could stay stable for a while, unless something will disrupt the strong Siberian high.
North Atlantic moisture north of the jet stream path will move into Barents from eastern Scandinavian peninsula and then into Kara and across into the central Arctic and Laptev - the seas where we are seeing the reduction in sea ice coverage in the past week.

DMI has a great forecasting tool showing the surface current and ice convergence level, where you see this situation causing ice to move east (From Barents/Kara towards central AO and Laptev) and ice compacting across the western Arctic (Viewed from the Canadian side):

http://ocean.dmi.dk/anim/index.uk.php

We will see what this means, but at least it helps building thicker ice in the central Arctic and the inbound moisture is not as warm as if it had arrived directly from the northern Atlantic..

jdallen_wa

To amplify a bit on what John Christensen said - I've been watching the forecast using climate reanalyzer, both looking ahead in the current time frame, and playing back last year at this time. (http://cci-reanalyzer.org/Reanalysis_daily/)

I find it useful to run the animation(s) to look for patterns - first temperature anomalies, then temperature, lastly precipitable water. By looking at reanalysis (recently Nov. 2014) and comparing that to the current forecast, I think it gives me a qualitative sense of how heat is moving in the system.

There are gross similarities between what I see currently forecast and 2014, which as John points out, has North Atlantic moisture moving across NW Europe into the Barents and Kara. On the western side, there are similar intrusions of heat into high latitude into Alaska - which appear a bit further east than they were last year, and not as persistent.

Where it differs, What struck me most about near term weather is the focal point of the circulation, which does seem to diverge from last year.

It seems like the focus of circulation has shifted south and slightly west, centering generally on northern Greenland and the area around Ellesmere Island. It implies to me some sort of influence by the Greenland ice cap, by way of supporting more persistent cold temperatures which is becoming a dominant force to controlling circulation, rather than a more central polar pressure system.

The effect appears to be one of constant flushing of cold air out of higher latitudes, with the effect of compressing the pack west as John suggests, exchanging that air for much warmer flow from the south.

I'd hazard some of what we are seeing might be attributable to El Nino; watching the circulation, you can follow plumes of moisture crossing Mexico and flowing from there across the SE USA, then along the Gulf Stream path into Europe, finally dumping out in the Barents and Kara.

Kris

Neven wrote:

... keeping the cold in the centre of the Arctic and winds pushing the ice inwards ...

Albeit the daily Reorganiser charts are showing quite the opposite? Showing since months almost the entire Arctic in an "over heated" state. And some borders [Bering Sea, NW Canada ecc...] quite a bit colder as usual? Addirittura, yesterday our other tool, Ogimet showed spots of -1 ºC and -2 ºC near the central Arctic!

So, whatever it could be, I'm afraid we really don't know much about the reason why.

John Christensen

Talking about the jet stream path: What an amazing swirl it makes across Europe; north-east across northern Scandinavia, then south-west down into central Europe, before it moves east again in a massive S shape.
It certainly moved the Siberian high to the east, as I had questioned a couple of days ago.
Let's see if the low off the coast of Norway will move south again or east into Barents.

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