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Jim Hunt

Enjoy the coffee Neven.

Once you're back at your keyboard I'll be very interested to discover the reasoning behind your "The minimum will probably be reached around that time" statement.

There's still time for more cyclones!


Hi all, I have been lurking for a few years reading the blog.

Isn't DMI already showing Arctic Ice Volume down to 2011 levels and already lower than the 'Rebound years'?


Though as you point out PIOMAS shows 2015 at a higher volume? (Though extent and area are both down compared to the last two years).


Will look forward to your analysis when you post it.


John Petroff

Cold air should be moving into the Beaufort Sea and Canadian Archipelago this next week. Curious if freeze up begins early or at least the decline stops for both extent and volume.



Sam Carana posted an update on the Sea Ice extent with a map from arctic-roos.org showing it dropping below 2012 line.

Could you comment on that please?

Here's the link: http://arctic-news.blogspot.ca/2015/09/arctic-sea-ice-collapse-threatens-update-8.html

Alais Elena

It is a mistake of some kind.


@ John P,

It would appear that an early freeze up has come going by the extent data for the 6th of September.

Hans Gunnstaddar

Looks like 4.5 million sq. kilometers extent is about it. That puts it 4th lowest unless something dramatic occurs like a hurricane. My guesstimate of 4.7 in the polls was just a tad off.

My guesstimate for next melt season is 3.7 followed in 2017 by a new record at 2.8


Big calls... but you have to live bold !!


DMI show just short of 6 million km2. Lower than the last two years but quite a bit better than 2011.


NSIDC put it at about 4.5 million km2

ADS actualy show 4.37 million km2

Near their 2007 and 2011 minimum extents.

Norsex somwhere between 5 and 6 Million km2
(Befor their error starts to show.)So hard to tell where it is.


Air temp above 80 N have been pretty cold in August and September.

Is there a known reason for such a difference between DMI Extent and the others?


Interestingly The old DMI gives an ice extent level about the same as 2008 and 2011 levels. So the respective datasets all give a low level of extent, around 4th or 5th lowest relative to their own past data.



BillV asked:

Is there a known reason for such a difference between DMI Extent and the others?

Assuming this isn't a rethorical question, the answer is "Yes".

And the "yes" means that each organisation is using it's own private standards.

NSIDC uses a mean figure of the 5 past days. ADS-Jaxa use a mean of only 2 past days.

We don't know really which standards the Dansks are using. But, for example, on their charts "the arm" still is almost entirely present. So, that alone could explain a 1 million square km difference.

Let's say they are a bit over cautious and concervative in Danmark. :-)


Taras wrote:

Could you comment on that please?

Nonsens like that shouldn't be commented. It's clearly a mistake, and we only can state Sam Carana doesn't check his home work before delivering it.


Thanks Kris,

Not exactly 'rhetorical' and DMI state on their site:

"The total sea ice extent can differ slightly from other sea ice extent estimates. Possible differences between this sea ice extent estimate and others are most likely caused by differences in algorithms and definitions"

Which is pretty clear I guess.

But I have wondered if there was a definate reason. And if a community interested in Arctic Ice like this might be more aware of it.

Anyway (unfortunately) it does not change the downward trend that all these data sets are showing in ice extent over the last 30 years.



John Christensen

Hi Kris and BillV,

DMI (And e.g. ROOS) includes the coastal areas in their measurements, which are excluded in most other SIE measurements, because historically the satellites were having problems identifying ice in coastal areas correctly.
Those SIE numbers, DMI and ROOS, are therefore probably more accurate if you want to know, how much ice there is in the Arctic, but other measurements excluding coastal areas are probably more comparable between recent years and the 80s and 90s.

Regarding the remaining slush of the MYI arm: It is still there.
However, some charts use a higher concentration threshold for showing ice, so while DMI will show ice with very low concentrations, e.g. Cryosphere Today only shows ice, where the concentration is 30-35%, even if their legend includes colors for lower concentrations.


@ Bill V

    In trying to be critical I could say, according to your source, that there seems to be some sort of a possible recovery of types in the surrounding months of August... but the truth remains that all months show long term decline!

The follow up question is: "..is this decline accelerating?" ("How do we go about proving and/or disproving that?", is the actionable request!!!)

Is there a known reason for such a difference between DMI Extent and the others?

Billy, I answered a very similar question on the forum recently:

Why is the DMi arctic sea ice extent so much higher than everyone else's?


My answer is here: http://forum.arctic-sea-ice.net/index.php/topic,143.msg60794.html#msg60794

Basically they are using OSISAF input data, not being sea ice concentration data, that is not meant to be used for the purpose of calculating extent.

Just by eyeballing the graph you can see something suspect. Looking at the grey (mean) line, notice the steps at some of the first of the months? Those are tell-tale indications of application of monthly ocean filters, designed to filter "false ice". Other extent sources use the same filters (originating from ice experts from NSIDC) but nowhere it is so visible in the graphs! This is a clear indication that the OSISAF data (on which the DMI graphs is based) contains a lot of this "false ice", probably the reason why they end up with such large extent numbers.

DMI (And e.g. ROOS) includes the coastal areas in their measurements, which are excluded in most other SIE measurements

This is incorrect, all SIE calculations that I know of (with one exception) include most of the coastal ice. That includes NSIDC (multiple extent calculations), ADS Jaxa (formerly known as IJIS), Bremen, Hamburg, ROOS and Cryosphere Today (it is sea area, just added to be complete).
The one exception is the DMI graph based on OSISAF sea ice concentration that has the coasts masked out. DMI calls this graph "old":

In the coastal region ice may be falsely detected due to the "land spillover" effect. All these calculations include measures to deal with that (with variable success).

Cryosphere Today only shows ice, where the concentration is 30-35%, even if their legend includes colors for lower concentrations.

For the record: the Cryosphere Today Area is calculated using a threshold of 0%. The DMI graph discussed here "thinks" it uses 15%.

John Christensen

Hi Wipneus,

Given the difference of about 1.0 MKM2 of SIE in summer and winter between DMI and other extent metrics, and this explanation on DMI ("The plot above replaces an earlier sea ice extent plot, that was based on data with the coastal zones masked out. This coastal mask implied that the previous sea ice extent estimates were underestimated. The new plot displays absolute sea ice extent estimates. The old plot can still be viewed here for a while."), I had assumed that e.g. JAXA had stayed with a more confined definition, so thanks for correcting that.

Regarding CT: Yes, the area calculation is based on all ice, but I was referring to the visual representation of ice, where DMI SIE allows us to view all concentration levels, while CT does not visually show concentrations below 30-35%.


Wipneus thanks very much for the explanation (and the link to the earlier one on the forum).

Reading the DMI site I had thought others were masking coastal ice and, as DMI were not, that explained the difference.

But their 'old' masked extent data gives lower totals than other data sets. maybe 3.5 million km2 today. So I wondered about this.

Thanks for clarifying that other data sets also don't mask coastal Ice.


Hi John Christensen,

regarding your comment

"Regarding the remaining slush of the MYI arm: It is still there."

I do note that the naval research labratory site show this present still for their Beaufort sea depiction


But mostly just as very thin ice


John Christensen

Agreed BillV.

DMI has yet another tool, where they even forecast ice thickness or concentration for the next four days:


As you see they still forecast little change for the remainder of the MYI arm, but that it will be compacted towards the general pack, as the gyre has started slowly.

Colorado Bob

New Study — Risk of Significant Methane Release From East Siberian Arctic Shelf Still Growing

Large plumes of methane bubbling up from the Arctic Ocean sea-bed, saturating the water column, venting into the air, adding significantly more heat forcing to an already dangerous, fossil fuel-based, accumulation of greenhouse gasses in the Earth’s atmosphere. It’s a nightmare scenario. One in which human-forced warming, already at 1 C above 1880s levels, is further amplified through the feedback release of ancient carbon stored over the past 8 million years of Northern Hemisphere glaciation. And a recent study by the now famous Semiletov and Shakhova team provides still more reason for appropriate concern that such an event may be in the works.


Jeff Dillon

For an interesting take on the status of Arctic ice from the perspective of research oceanographer Jim Swift, who just reached the North Pole: https://scripps.ucsd.edu/expeditions/arcticgeotraces/amundsen-basin-of-the-arctic-ocean/

"At 7:47 am ship’s time Saturday, September 5th, USCGC Healy became the first US ship to reach the North Pole unaccompanied by another icebreaker. I am not certain of this, but Healy may also be the first ship of any nation to reach the pole from Bering Strait unaccompanied. It was also a milestone of sorts for me, because there have been three scientific crossings by surface ship from Bering Strait to the Pole – 1994, 2005, and 2015 – and I was on all three, doing similar work each cruise (and thus learning about ocean change in this remote part of the World Ocean).

My informal observations of the Arctic Ocean sea ice we have been traversing continue in the same vein as during the past two weeks: much of the ice appears to be first-year ice and passage through it has mostly not been difficult. "


Jeff Dillon quoted:

... from the perspective of research oceanographer Jim Swift...

For sure Jim Swift ia a man of science, nevertheless he (and his fellow companions) missed the scoop as well as the most worrying important:

There was a seal near the ship at the Pole and people saw bear tracks on the way here, so the ecosystem we associate with the Arctic Ocean – a simple food chain from phytoplankton & algae, to zooplankton, to Arctic cod (a small fish that lives under the ice), to seals, and finally to bears – is active even at the Pole.

Seals and their Icebear preditors shouldn't have any business in the center Arctic, at more as 1500 km from their natural habitats. Because the ice field is to dense thus the distance from one air hole to the next one is to long to allow seals to breath and evolve. And of course, where no seals are there won't be icebears either.

So, if seals are appearing in the center Arctic, even at the Pole, it means the ice has been fragmented that much already that seals are able to live and feed there. And icebears have been forced to follow their dinners into an rather icebear unfriendly environment - over 1500 km away from their natural habitat.

Making me repeating myself in saying 2015 even has been even worse as 2012.

It won't be a good nighty night sleep for me...

Alais Elena

That is a very telling observation, Kris. Thanks for pointing that out.


Robert S

Your comment, Kris, aligns with my observation that we are seeing state changes in the Arctic system - state changes which are not (yet) reflected in single variable measures such as ice extent or volume, but which will ultimately impact those measures. The interesting question now for me is how to integrate the current ice state into models, as well as to run scenarios of future ice states... but I'm a model geek.


Hi Jeff thanks for the link of Jim Swift's. Really interesting stuf.

Kris, they may not have thought of it as a scoop. Although rare, sightings of Seal and Bears are not unknown.

His comment about the ease of getting there through first year ice is still a worry though.

"Stirling (1990:65–66) reports that “Polar bears or their
tracks have been reported, albeit infrequently, by various
explorers almost as far north as the pole,….[but] This is

"Todd and others (1992) list bird and seal species sighted
at the North Pole by themselves and others, but no polar
bear sightings are known at or near 90˚N. Their list includes
animals at the Pole and very near it—snow bunting
(Plectrophenax nivalis) (May 1987), northern fulmar
(Fulmarus glacialis) (August 1991, July 1992), blacklegged
kittiwake (Rissa tridactyla) (July 1992), ringed
seal (July 1992), and small fish (5–8 cm), the latter swept
up onto the surface as the ship crashed through the ice.


Remko Kampen

Losing faith in the PIOMAS output. I can't see very well why this year's volume wouldn't simply be the lowest. I'll bet Nanuk knows.

Kevin McKinney

I'm about ready to call the 8th the minimum in JAXA--today's update will do it for me if there's no increase.

The 2015 minimum extent value (JAXA flavor, of course) would then be 4,358,918 km2, which (unsurprisingly to most here) would be 4th lowest, behind 2012, 2007, and 2011.

Of course, I've got no money riding on it--it probably won't be completely 'safe' for another week or so. We'll see--which seems like my constant refrain in matters Arctic.

Susan Anderson

Interesting and useful discussion, thanks.

Don't know how it will affect events further north, but two observations.

The northeast US has often been 10-15 C above average for weeks. Ocean temperature is finally dropping off Boston.

And being an extreme weather buff, I've been following Kilo, and checked Etau which just devastated Japan with heavy rain, and it appears Kilo is now heading north towards the Bering Sea.

This shows current overall NH circulation (water vapor):

I'm also wondering, seems to me the melting season is extending.

Susan Anderson

Correcting my information, seems a lot of the energy from Kilo is being absorbed by the Kamchatka Peninsula. Tanada comment on other article made me look at Nullschool, which if your computer has good bandwidth, provides an excellent visual here:

(for those not familiar with it, you can move it around, zoom, and click on "earth" to get different parameters)

G man

Susan=[The northeast US has often been 10-15 C above average for weeks]This would've put Boston (avg 80F/24C for Aug)btwn 93F-102F throughout Aug+! Perhaps you meant 1-1.5C. That would still be 2X-3X what recent lower tropo satellite data show for Aug in the far NE.

Wayne Kernochan

Delurk: I live in the area -- she meant 10-15 degrees Fahrenheit. However, on Tuesday and Wed. of this week it was 20 degrees F or 11 C above normal in Boston, setting a record both days.

Susan Anderson

No, I meant three weeks or so but you're right, in Fahrenheit it's been in the 90s (32+ C),when it's normally in the 70s (21+ C), and not every day, and I miscalculated.* I should have stuck to 10 C or more. And nights have been even warmer compared to what used to be normal. I was not talking about averages but what might affect current conditions in the not so far away north. (what's a thousand or two miles among friends, after all ...)

We're not that far from Greenland oceanly speaking.

Also, in the years since I came to Boston, average has already crept up and was anecdotally thinking of the whole time I spent here rather than the 90s and oughts. I also spend a lot of time in New Jersey, where it has been obscenely hot for longer and more consistently, but the time I measure against was even farther in the past.

C = 1.8 x F

Susan Anderson

I'd best mention for clarity that 10 degrees F = 18 degrees F which is added to 32 which is freezing point.

Hans Gunnstaddar

C x 1.8 + 32 = F

So if it's 22C, then it's 71.6F


Does look like we're at the minimum unless there's serious winds or temperature anomalies that kick up. Don't see much forecast in in the next 7 days from http://cci-reanalyzer.org/Forecasts/ NCEP GFS


UltraVerified wrote:

Does look like we're at the minimum ...

Of course.

According to the temperatute anomalies for the Arctic at Reanalyser --> Arctic temperatures will be above avarage, except for the very Arctic center. Meaning it probably will be something like a stall for the next week, or better, there would be only small dayly 'upticks'.

For Baffin Bay temperatures would be slightly above average too. Whereas it would be a different story for the Greenland mainland where temperatures are expected to be highly above avarage. Meaning the big floating glaciers such as Ilulissat and Helheim would further be prone to extensive calving events.


I'm about ready to call the 8th the minimum in JAXA--today's update will do it for me if there's no increase.

The 2015 minimum extent value (JAXA flavor, of course) would then be 4,358,918 km2,

Kevin, I think you are right about calling the minimum, but the minimum value on JAXA was 4,279, 543 sqkm on the 8th; which puts 2015 in 4th position on the scoreboard behind 2012, 2007 and 2011 (by a whisker!).


High pressures seizing Beaufort-Chukchi means big drop of temperatures and Ekman sinking. Refreezing over those regions is inminent, only a couple of days of strong compacting winds over Laptev-ESS side, and that's it. I call it.
Minimum was Sep 8, extremely close to 2011, next season prospects are negative for the Arctic sea ice.

I'll bet Nanuk knows.

Of course, he knows, he has the script! ;-)

I'm about ready to call the 8th the minimum in JAXA--today's update will do it for me if there's no increase.

I totally agree, Kevin. Thanks for calling it. Only hard-core compaction via an Arctic Dipole (high over American side, low over Siberian side) can prolong the melting season now. On the conditions that there's enough compaction potential, of course.

But there's none of that in the current forecast.

Frankly, I can't wait for next year's melting season!

PS traveling home tomorrow.


@ Remko,

A weird September 12 Arctic Sea Ice Extent seems to illustrate strange activity.


Strange or not, Sep 13 new Jaxa min. Third lowest, below 2011. The couple of days of strong compacting winds did it. I eat my own words.


Correct: New extent minimum ( according to JAXA 13 09 2015) : 4,268,045 sqkm. 2011 minimum was 4,269,199 on 9th Sept. This double dip looks very much like 2010!



What we observe is the strange back and forth clockwise counterclockwise circulation of the main Gyre, same as every summer since 2013 Maximum. This years circulation was clockwise on a few more occasions than 2014, less than I imagined. In 2013 it was perhaps -----nil---- over all equal clockwise and counterclockwise gyres. What we see is how sea ice will eventually completely go: 'melting in place'. Not very exciting, slow like AGW; a 1 mile per hour train crash on 25,000 miles track.

This said my own a few weeks ago words predicted the minima to be later than usual, as it appears to be so, on JAXA 50,000 km2 apparent melt today, it is not really a melt, is the Gyre turning as it did in the not so long ago past with some melting from the very warm Arctic Ocean surface water. Now is really when we realize there is a change, especially dynamically. This winter looks bleak for sea ice, clouds from perhaps the strongest El-Nino in recorded history will slow the refreeze accretion in darkness, if a reverse strong La-Nina returns come May 2016, the March 2016 Maxima will appear grand and extensive with very thin solar ray vulnerable sea ice, if so, next years minima will be very small, despite the gyre turning more often than not, not at all.


For what it is worth DMI shows a distinct drop in ice extent for the last two days.


Kevin McKinney

"Kevin, I think you are right about calling the minimum, but the minimum value on JAXA was 4,279, 543 sqkm on the 8th; which puts 2015 in 4th position on the scoreboard behind 2012, 2007 and 2011 (by a whisker!)."

I wish! Sic transit gloria, and all that!

Although there may be a glimmer of hope, in the form of a revision. They do sometimes do that, I've noticed (and actually I'm pretty sure that's what led to the discrepancy between the number I typed and the number Phil (correctly) gave later.)

Certainly, today's sharp drop looks a tad suspicious. No time to check the weather setup right now, though.


Kevin, " today's sharp drop looks a tad suspicious"

not in the least bit! Like deep throat said but with a met twist "follow the weather" the Gyre is normal for a while.......

Kevin McKinney

Down to 4,257,003.


Colorado Bob

In 2014, an international research team led by Semiletov set sail to the Arctic Ocean on the Oden icebreaker science vessel. The researchers were the first to closely examine the waters of the outer West Arctic continental shelf at depths below 50 meters, and it turned out that carbon emissions in the shelf zone are much more intense than expected. Up to several hundred grams of methane per square meter are emitted daily, which shows that the underwater Arctic permafrost has been degrading severely. About 700 such “methane holes,” each up to a kilometer in diameter, have been found in the shelf.


Susan Anderson

Thanks Hans Gunnstaddar for cleaning up the mess I made by failing to proof my correction of my correction. I thought I'd best hide my ignorance for a few days, but some good may have come of it for me personally at least.

Firstly, I've been viewing those addictive water vapor animations and the various communication areas between the middle north Atlantic and Pacific and polar regions and now have a better idea of what is in the way of direct transfer of energy.

Secondly, in terms of what I was trying to say and or think (if you could call it thought) it was to reflect on the change as also including a general lengthening of the warming season at both ends, which may or may not give us a few more days of slight melt before the "official" minimum. This is possibly not as consistent with the far north, as the dropoff in daylight has not changed.

Probably not connected to my thoughts about Boston's north shore water not really cooling until late September or October and how that might be reflected further north, today I noticed some hot spots at the northern end of Greenland, after an absence of melt a couple days back (haven't checked daily).


Those are cool satellite image clips, Susan, but be careful. Those water vapor clips show cold high cloud tops, not the total precipitable water content of the column of air. The precipitable water content in dark subtropical areas is actually higher than it is in bright white polar areas. Because water vapor is a powerful greenhouse gas, it has a strong effect on the radiation balance.

Clouds and water vapor hold in heat in the dark months so increasing amounts of vapor advected from warm subpolar oceans into the Arctic is an important factor in polar amplification of global warming. That's why I expected the "blob" to cause sea ice volume to drop over the past year.

Susan Anderson

Thanks D, for the informative translation of a broader perspective. Yes I know water vapor is only one way of looking at a much bigger and more complicated pattern, and of course daily observations are severely limited as well.


Susan & D,

sitting in Paris under a considerable column of "precipitable water" is one thing. Looking at the 300 knots jetstream at 250 hPa ( see http://earth.nullschool.net/#current/wind/isobaric/250hPa/orthographic=-10.91,55.35,1068 ) makes you wonder what is more important these days. During last nights twisters and rainstorms, three people were killed in France.

Susan Anderson

Thanks, Nullschool is a favorite. I fiddled with closer to the surface, a more broken pattern. Fascinating.

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