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Jim Hunt

Thanks for the latest update Neven.

However let's not forget that there's been a slight difference of opinion between PIOMAS and CryoSat 2. According to the European Space Agency:

Measurements made during October and November [2014] show that the volume of Arctic sea ice now stands at about 10 200 cubic km – a small drop compared to last year’s 10 900 cubic km

Here's CryoSat 2 in Autumn 2014:

Click the image to see a high resolution animation over on the Arctic Sea Ice Forum

I Ballantinegray1

I'm very much in agreement with your closing statement Neven! Since the turn of the century the '2 year rebound' seems to be the measure? Maybe it's just playing the odds in a system where 'average' summer can bring us 2012 melts? Surely the odds are stacked toward the 'warm' or 'average' season and not 'cool'? Maybe the whole of the Arctic system is in flux and is responding to the huge volume losses over the past 50 years ( with the move to more 'open water' being the final straw?).
As for this year? Well Fram is still well and truly open for business so we continue to shed older ice in favour of late grown FY ice ( even if it is being compressed/over ridden on Greenlands north shore?) So the basin has not been 'static' over re-freeze with older, stronger ice being swapped for younger ,weaker ice. Beaufort has been fragmented and stirred and Nares has only recently arched shut.
As ever I'm looking forward to an interesting melt season to come but I'm even less hopeful of another year of consolidation and fearful of another downward jolt esp. if global temps remain high?

Werther

Thanks, Neven!

Not much to post on lately, waiting for sunshine to revive the MODIS tiles. I saw yesterday the Beaufort Sea is getting visible N of the Mackenzie delta. The enhanced picture shows the usual thin ice and loose floe distribution north of the fast ice. Soon the usual spring polinya over there may start to form.
The lack of winter power out there might help. Positive mean winter temp anomaly varies from +2dC (Toktoyaktuk region) to +4dC (Barrow region).

The whole stretch from Bering Sea through the Strait and well into the Chukchi Sea looks like it may settle for a surprising early melt season.

wayne

The dynamical meteorology change in the Arctic is rooted in Global Warming. But does not necessarily give the appearance of warming at times, especially in the summer, what is key to remember is extent numbers reaching all time lows at times during the yearly cycle. When this happens, it is an indication of the potential
for ever more greater minimas. PIOMAS volume changes does not reflect this potential, rather gives trends as a result of mostly summer weather dynamics ice pack expansion not compaction. This season so far had great influxes of warm cyclones from North Atlantic Northwards affecting roughly half of the entire Arctic Ocean pack, I suspect the volume less then projected, and I am not surprised if PIOMAS may be off.

If you manually drill sea ice in a very small area there can be significant differences in thickness. So any model not having a 1 meter resolution base would give erroneous results.

"Arctic-wide thickness losses are more difficult to document because of the sparse sampling in time and space. - See more at: http://www.realclimate.org/index.php/archives/2012/04/arctic-sea-ice-volume-piomas-prediction-and-the-perils-of-extrapolation/comment-page-2/#sthash.ifiqdF6B.dpuf"

Using the scant buoy data itself to integrate actual sonar ice depth gives the same problem as with manual ice observations.
A possible work around would be to actually scan a wider area of sea ice thickness before placing a buoy, in the hope of having a better representation of an ice field.

But I think we need calibrate ourselves with some aspects of ice data as presented, which is compare extent, likely JAXA with respect to Piomas, if the extent is near all time low (like now) and
Piomas trends the other way (like now) , there should be a bit of skepticism with respect to the PIOMAS volume projection.

VaughnA

I have been too swamped at work(high school teacher) to post much lately but have mostly managed to keep up with at least reading this blog....

The Climate Prediction Center

http://www.cpc.noaa.gov/products/predictions/multi_season/13_seasonal_outlooks/color/t.gif

forecast shows above normal temperatures over all/most of Alaska for the next six months and above normal temperatures along the Alaskan Arctic coast for an additional six months after that. If this plays out as indicated then the "surprisingly early melt season" Werther suggests will become a reality. Then warm conditions over northern Alaska would continue to be a source of warmth to spread northward during the summer into fall.

NCEP SST Analysis http://polar.ncep.noaa.gov/sst/ophi/ also shows warmer than normal water temperatures in the far north Atlantic pushing against the Arctic ice there as well.

Yes it should be an interesting melt season.

jdallen_wa

I'd say watch the peripheral seas.

There's not much thickness in the ESS, Kara and Barents. The Chukchi has some, swept in from the Beaufort. And of course, the Beaufort has MYI swept out of the central basin.

I think we could see a lot of "melange" - broken/pulverized younger ice around islands of older more durable. In the ESS/Laptev in particular, we see early breakup and melt - especially if Siberia gets hot and rainy, increasing river outflow.

If the peripheral seas clear quickly, the extra volume may become irrelevant, if MYI volume gets pushed out into seas which because of early melt have been driven by insolation to near 0 degrees or above. At one point last August, parts of the Laptev broke 4C....

The heat forcast for Alaska does not bode well for the Bering and Chukchi. They froze late, and may not get the chance to thicken particularly.

In short, we may have more volume, which is great, but I'm worried about the edges collapsing and letting the heat get to the central basin earlier.

Jim Hunt

Werther - You could always watch the Sentinel 1 tiles over on the Nares Strait thread on the forum whilst you wait:

http://forum.arctic-sea-ice.net/index.php/topic,176.msg44895.html#msg44895

Must be quietly becoming the most interesting thread on the planet.

The southern (and thus far only) arch has just been dislodged by strong winds.

Werther

Jim, hi,
Have you found an access to daily Arctic Sentinel-1 imagery yet? Maybe Wipneus has. I see DMI has been collecting some around Greenland since last October. The images do give an exciting lot of info on structure and movement of the ice. On first sight, the pixel when downloading them as jpg looks even smaller than in MODIS.

Combined with MODIS (which remains the leading source for me because I’ve been using them quite some time) and ASCAT (which provides a good, though less detailed, oversight) the SAR images will give much better handle on interpretation of ice quality next summer.

BTW the SAR images of Nares Strait are impressive; it looks like the ice out there is more mobile than ever.

Jim Hunt

Werther,

Senntinel images are available to all and sundry via:

https://scihub.esa.int/

You do have to register first. Personally I find the user interface rather painful! Wipneus has nonetheless been producing some very pretty images from the ESA S1A "quick looks":

http://forum.arctic-sea-ice.net/index.php/topic,176.msg42492.html#msg42492

Wipneus

Werther,

The resolutions of the Sentinel 1 products vary, with 10, 25 and 40 meters/pixels the most common. Far better than MODIS, usable day and night, clouded or clear skies. They tend to be a bit less clear due to the "speckle noise" common to SAR imaging. A Landsat 8 image taken under the best conditions will be better, but those conditions are rare.

One problem is the size: 1, 4 and 8GB single slice data products are an indication.

ESA seems to have problems at the moment with populating the public archive (that Jim pointed to). For Greenland most products after Jan 27 have yet to appear. DMI appears to get their data via a better route.

NeilT

Jim that interface is designed by people who simply don't want you to get the data unless you already know how to get the data.

Having worked at ESOC I'm not highly surprised but as a mere mortal I think I'll stick to places who actually want mortals to view their output....

Jim Hunt

Drifting slightly off topic, in a generally southerly direction, I bring news that a big chunk of ice shelf has recently calved in the Eastern Antarctic:

You will also note that the celebrated "Arctic Penguin" (AKA "Wipneus") has recently taken a trip to his ancestral home, and his trusty Raspberry Pi is now producing regional Antarctic area and extent data.


Arcticio

http://www.polarview.aq/arctic

has recent Sentinel-1 SAR imagery in reasonable file sizes.

Jim Hunt

Thanks for the tip Arcticio! That is MUCH easier to use.

There's even a southern hemisphere version:

which is the broken chunk of ice shelf I mentioned above on January 30th.

Cincinnatus

Someone said the Kara Sea has thin ice. It does not, it's been very cold there for 2 months and the ice has thickened. 2 years ago it retained some ice to August and it looks to do that this year too.

Werther

Kara Sea forecasts…

 photo Arctic detail Winter power Temp 1000Mb  0110 to 05022015 small_zpstxawr1wp.jpg
‘Winter Power’, mean temp anomaly on 1000Mb by NCEP/NCAR.

This detail represents the period 1 October – 5 February. Step is 1 dC, range is -2 dC near the basis of polu’ostrov Jamal (indeed, Kara region) to +5 dC around ostrov Wrangelja. The stubborn north Kara Sea icefield during summer ’13 came about after a winter with mean +2-+5dC anomaly in the Kara. Last winter (13-14) had +/-0-+4dC anomaly.
In my eyes, winter power may be a good proxy for mean Arctic ice accretion, but not for regional extrapolation into the melt season. Certainly not in peripheral seas.
I suppose there could be an effect near Severnaya Zemlya at 80dN, but at the Southern part, Baydaratskaya Guba, 70dN, summer weather will almost certainly overrule winter power, even though it had -2dC anomaly. Nevertheless, Rosneft will have a difficult task coming spring producing oil in the Pechora Sea.

Cincinnatus

In response to Werther, I was watching the Kara temperatures over the 2012/13 winter and it was easily colder there than previous winters. If the "official" Kara anomaly was +2-+5, then 2 observations about that: (1) official figure is wrong (insofar that the actual average was outside of their 90% confidence range), and (2) the 4 degree width of the anomaly shows they don't really know what was happening.
Of course, the anomaly could be that high if their baseline temperatures are falsely low. On that topic, on the Nares Strait thread there is a posting: http://forum.arctic-sea-ice.net/index.php?topic=176.msg44603#msg44603 which shows a ridiculously high Greenland anomaly. That angry red makes it look like Greenland is covered in molten lava, but as another poster pointed out, the actual temperature was -20C. Two things were happening here, (1) strong winds were blowing across Greenland, and (2) the baseline temperature for Greenland was taken as -55C -- thus the silly red color. But strong Chinook winds blow across Greenland all the time, so this event was not unusual. The silly red color was just an artifact of how they are measuring things, but you can bet it went into the calculation of how much the Arctic has heated up.
Similarly, the Arctic melt-off of 2012 was largely an artifact of the 15% threshold below which the water is deemed to be ice free. There was a lot of 5%-10% slush in those waters, and a large patch of ice north of Wrangel was ignored which then magically re-emerged as "old ice" at the time of the rapid re-freeze.
So my point is, this site and the posters here take the measurements as more authoritative than they should. Climate science is falsely precise with its blandishments, no other scientific discipline acts this way -- well, except for the medical sciences I suppose because of all the money that is in it. So I recommend you all take the published figures with lots of grains of salt -- elevate the uncertainties into your consciousness.

Neven

You don't like the colour red, do you? :-P

Uncertainty is not our friend, so if you don't mind, we'll keep comparing the numbers, however precise or imprecise they are.

Jenny E. Ross

Hi everyone,

FYI, here's a recent magazine feature article about Arctic sea ice that I wrote and photographed. (It was published in October, but I've just received a PDF I can distribute.) http://www.lifeonthinice.org/data/web/JERoss_ArcticSeaIce_OceanGeographic_201410_LowRes.pdf

Cheers,
Jenny

Jim Hunt

Hi Jenny,

Thanks very much. Beautiful! See also:

"Life On Thin Ice"

I hope that's OK with you? Any chance I could add one of your amazing photographs to that thread?

Werther

If the temperature reanalysis under supervision of NCEP/NCAR needs any re-evaluation, I’d suggest to do the homework on the raw data for a check-up. There are eight relevant, long time reporting Russian weather stations around the rim of the Kara Sea:
Malye Karmakuly (though on the Barentsz Sea side of Novaya Zemlya)
Amderma
Ostrov Belyy ( GMO im Popova)
Ostrov Dikson
Ostrov Golomjannyj
Ostrov Vize
Polar GMO im E.T. Krenkelj (Ostrov Kheysa)
Mys Zelanija

Good luck and let your inspiration be Christopher Bookers’ ridiculous Paraguay data flaw.

Speaking for myself, I’ve been fiddling with these temp data and SST’s intensively in the period October ’10 – January ’12, a period featuring ‘The Kara Bulge’. A 500Mb pressure dome resembling a bit the ‘Ridiculous Ridge’. A nickname I think VaughA introduced for the long lasting ridging over the Gulf of Alaska stretching South well down to the Californian Pacific.

There is nothing in the data that looked unrealistic to me. In fact, the relative warming in the Kara Sea in the period (appr!) ’05-’13 is in line with strong influx of Atlantic waters through the Barentsz Gate and the West Spitsbergen Drift during that period. As described by Årthun et al 2011.

The present ice extent in the Kara - and Barentsz Seas reflect a temporary dip in this influx. During summer ’14 it coincided with strong ridging on the axis Greenland-Scandinavia and mean Northern winds in the region Svalbard-Frantsa Yosefa. It is one of the factors that produced the ‘rebound’ in summer maximum extent as well as the ‘not so much melt’- volume effect in PIOMAS.

For a reminder; ‘winter power ’12-‘13’ showing +2-+5dC mean anomaly over the Kara Sea. Nothing indicates that ‘they have no clue’:

 photo Air temp 1000Mb anomaly 15092012 to 14022013 very small_zpsy2i32uyt.jpg


Jenny E. Ross

Thanks very much, Jim! It would be fine for you to add a photo, but I don't know how to provide one to you via this site. You can grab one from tweets I've sent in the past few days to publicize the article on my Twitter feed -- @LifeOnThinIce. Or please email me directly.

Cheers,
Jenny

wayne

The newish downward trend in sea ice extent goes back to the "santa storm" , a much forgotten event in populated areas because it caused rain instead of 3 feet of snow. http://eh2r.blogspot.ca/ Nevertheless there is a link between the heat it brought further North and less Sea ice extent. There hasn't been such a strong storm heading Northwards, but several smaller ones, not as warm, but enough to burry Boston. Al were and are l heading to the same Arctic locations. However none so massive as seen during recent twilights.
Darkness has set at the return of the sun.

VaughnA

Werther, no "The RRR ‘Ridiculously Resilient Ridge’ Returns to California By Christopher C. Burt" came from Weather Underground:

http://www.wunderground.com/

I have been hit with several subtropical deluges with temperatures running 5-12˚C above normal so there is only minimal snow on the ground below 5500ft. elevation. Even high elevations 7000ft+ have well below normal snow in this area.
In between these deluges it has been warm and dry. Today the temperature was 17˚C. about 7˚C above normal. The "RRR" has deflected much of the moisture along with warmth to Alaska and beyond during these dry warm periods.

Vaughn

Jai Mitchell

The term "Ridiculously Resilient Ridge" was first coined over at the California Weather Blog.

http://www.weatherwest.com/

Jim Hunt

Slightly belated thanks for the image over on the ASIF Jenny. Here's a slightly smaller version:

wayne

Well Jay , RRR is not an easy thing to understand unless you know where the coldest air is, from that point everything is clear. Remains to explain why the coldest atmosphere is not moving much, just like the RRR, and this I do http://eh2r.blogspot.ca/

Chris Reynolds

Jenny E Ross,

I've just read your article on the loss of Arctic sea ice and its implications. Very well written and researched, I wouldn't disagree with any of it.

Ghoti Of Lod

Article in Skeptical Science by Jennifer Francis the introduces the evil twin of the RRR - the "Terribly Tenacious Trough"

http://skepticalscience.com/warming-arctic-weird-weather.html

also see the published science behind the cute naming.

http://iopscience.iop.org/1748-9326/10/1/014005/article

where Francis introduces new ways to quantify the waviness of the jet stream. Chris you'll probably want to take the time to read this new one.

Jim Hunt

Ghoti - Don't forget the recent review paper by the likes of James Screen and Judah Cohen, as well as Jennifer Francis:

http://epic.awi.de/36132/1/Cohenetal_NGeo14.pdf

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