# JAXA timing worst ever – switching Arctic Sea Ice software, right as the minimum is about to happen

It looks as if we are about to see the turn in Arctic sea ice, and if so it will be earlier than last year. But right at that same time, JAXA has decided to switch horses mid-stream.

They say timing is everything, and this timing couldn’t be more wrong. You”d think they would have waited until after the minimum had been recorded, so that there would be no questions or issues with the timing. But for some reason, JAXA has decided that now is the opportune time, right when everyone is watching. An update on their Arctic Sea-Ice Monitor page dated September 6th shows that they are switching from Version 1 to Version 2, and revising 2012. Of course the revision is for less ice:

In Sep. 2012 the arctic sea ice extent renewed the smallest record in observation history, but as the result of the version 2 using AMSR2 data of 2012, minimum sea ice extent became 3.18×106km2 which was 0.3×106km2 smaller value than Version 1 result using WindSat.

Here is what they display, on the plus side, at least they are keeping version1 in place until September 30th:

I have overlaid the two graphs, and it looks like all of the sudden about 250,000 square kilometers of ice has disappeared.

Note: I don’t have issues with their methodology, which is to remove uncertainty/noise related to the land mask boundary, which is always a good thing. But, the timing is certainly odd.

=============================================================

From their update page:

(1) Modification points according to the upgrade of AMSR-E data

With the version upgrade of AMSR-E Level 1 brightness temperature data, geolocation errors were improved from ±10km to ±1km.

The Version2 sea ice extent was calculated after the analyzing the arctic sea ice concentration derived from the upgraded AMSR-E brightness temperature data.

In addition, the other satellite observational data (1980, 1990, 2000 and 2010′ s average of SMMR, SSM/I and WindSat) was used to calculate sea ice concentration after adjusting the brightness temperature of each sensor using AMSR-E as standard data, and the adjustment of the sea ice concentration threshold which counts the sea ice extent was applied to consist with the AMSR-E sea ice extent.

The modified processing point due to the improvement of the geometric precision of AMSR-E Level 1 brightness temperature data is shown on description below.

(i) Cancellation of Land Expanded Mask

With version 1, sea ice can be falsely detected along coasts due to contamination of ocean pixels by the passive microwave emission of land (the false sea ice). To decrease this false sea ice, we applied the “land expanded mask” (See Fig.1).

By improvement in AMSR-E geometric precision and decreasing of the false sea ice, we stopped the land expanded mask in the processing of version2.

Compared to Version 1, Version 2 sea ice extent has increased.

(Reference) Principle of the land expanded mask

For the purpose of eliminating the false sea ice near the coast, Land Expanded Mask consider horizontally and vertically adjacent pixels as land when the 3×3 box centered on the land pixel.

(ii) Modified Land-Ocean Mask

Version 1 used the land-ocean mask which is provided for SMMR and SSM/I, but for Version 2, due to the AMSR-E geometric precision improvement, we made new land-ocean mask which is adjusted for footprint size of the 18GHz band of AMSR-E (IFOV: 16×27km) and applied to the analysis of sea ice concentration.

Compared to Version 1, the sea ice extent of Version 2 has decreased.

(iii) Utilization of Land Filter

In version 2, the false sea ice near the coast has decreased by the geometric precision improvement of the AMSR-E. But the false sea ice still cannot be removed completely, so we applied the land filter which Cho (1996) proposes. When at least one of 3×3 pixels was inspect as land, as the considering that the central pixel is effected by land spill over and has increased in sea ice concentration, central pixel will be replaced with the minimum value within the 3×3 pixels.

By applying this land filter process, sea ice extent of Version 2 has decreased in the melting period compared to Version 1.

(2) Release of AMSR2 observation data

After the observation halt of AMSR-E, the sea ice extent was calculated by WindSat in Verion 1, but in version 2, it was replaced by AMSR2 since July 2012.

In Sep. 2012 the arctic sea ice extent renewed the smallest record in observation history, but as the result of the version 2 using AMSR2 data of 2012, minimum sea ice extent became 3.18×106km2 which was 0.3×106km2 smaller value than Version 1 result using WindSat.

Furthermore, there is no modification in ranking of the successive sea ice extent due to the latest upgrade.

Fig.4 Arctic Sea Ice Extent during the minimum period

(Left:Ver.1, Right:Ver.2) – click to enlarge

## 144 thoughts on “JAXA timing worst ever – switching Arctic Sea Ice software, right as the minimum is about to happen”

1. MJBinNM says:

Of course they’ll compare current V2 extents with older V1 extents to show that it is indeed worse than we thought…

2. Kev-in-Uk says:

ready for supporting AR5?

They would not do this so that minima looks comparatively smaller, could they? Nah, our gov labs never skew the data on climate change issues, do they?

4. John says:

Anthony, question from the bleachers here… if they adjust this year’s model or data, would they not have to adjust all preceding years as well?

5. So the 2013 recovery is better than we thought?!

6. Eliza says:

Your all so naive here its beyond belief I have been shouting from the roof tops for years how these guys manipulate ice extent ALWAYS when it appears to be NOT going the desired way. CT etc are all the same they CANNOT AFFORD to lose this last precious icon of supposed AGW DMI and norsex both Scandinavian may be trusted.

7. it’s one of the AGW miracles, adjustments always going in one direction
as far as I’m concerned it’s a small step away from deception

8. So are they going to reduce the 1979- 2012 sea ice area by “0.3×106km2” ? And how many times have they done this since 1979? How do we know if they are measuring sea ice the same way as they were in 1979? Maybe the steady reduction in sea ice is simply the steady software/measurement method updates over the years.

9. Mark Bofill says:

Oh, don’t worry. They’ll adjust for it.
/sarc

10. Stephen Richards says:

If you scan the web you will note that no two ice extent measuring services give the same value and they vary by nearly 10^6 km².

11. In terms of data manipulation and distortion (and I agree with Anthony that it’s not happening here); when it does happen, it can only go on so long before it falls into the “give them enough rope” category.
You really can feel some of the people all of the time, as Lincoln said, but not all of the people all of the time.

12. At least they adjusted all the previous years too so the relative changes don’t look terribly messed up. (And didn’t do the GISS trick of cooling the past.) The percentage improvement from the 2012 minimum to 2013 might be significantly greater.

13. Steve Keohane says:

Funny how ‘corrections’ to climate related data are always in one direction, that is whatever makes the most dramatic change to prop up the ‘It’s worse than we thought’ meme. I remember going through the older CT images for NH ice and found they changed the sea edges by showing snow extent. This coincides with the step function at 2005. I found the sea area had diminished by pixel count the amount of the step, some 4-500K sq km.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.arctic.png

14. Frank K. says:

Ric Werme says:
September 6, 2013 at 9:47 am
I agree with Ric that it shouldn’t really matter as long as all previous years were consistently adjusted. Moreover, the increase in sea ice extent from last year will be quite obvious.

15. Louis Hooffstetter says:

omnologos says
“it’s one of the AGW miracles, adjustments always going in one direction.”
I agree. Does anyone keep track of these “one direction adjustments”? If not, perhaps we should encourage Anthony to set up a separate tab where we could track them. It might be enlightening to see just how many “one direction adjustments” to temperature data, ice data, tide data, weather station data, etc. have been made. It might be equally enlightening to see who made them and when.

16. Bryan A says:

So is this Climate Change or just Climate Data Change?
I wonder if Mikes Nature Trick could be used to Hide the Decline?

17. dbstealey says:

Eliza says:
“Your all so naive here its beyond belief I have been shouting from the roof tops for years…” &etc.
Eliza, some of us, probably most of us, are on the same page as you are. Note omnologos, Steve Keohane, Louis Hofstetter, Ric Werme, Harold Amblet, etc., etc. [sorry for all those I left out].
We all see that CT is diddling with the data. Arctic ice is rapidly increasing, as the data shows. Once again, the alarmist predictions have been shown to be 100% wrong.

18. AnonyMoose says:

It’s the start of the school year, and they have a fresh batch of interns with new ideas.

19. gaelan clark says:

If it is a land mass correction then shouldnt the correction be the same across the board…on all years the same amount of change?
I see variable changes, year over year, in the differences between the minima when they should all have the same step wise land mass correction.

20. Lawrence13 says:

These people are liars and should be put trial for mass public deception. Disgraceful what other purpose could there be but deception.

21. Alan S. Blue says:

Note that this has happened for the “1980’s average” and “1990’s average” as well. As far as I’ve been able to determine, they weren’t updated to become “apples-to-apples” either. With exactly the same issue – determining the land-sea boundary. (And then not re-evaluating every single photo.)

22. geran says:

JAXA was a source I thought I could trust–guess not.
Timing shows either corruption or incompetence, so no “explanation” will suffice.

23. Lawrence13 says:

Anthony
You increasingly have some ‘clout’. Have you emailed them?
REPLY: Thanks, but say what? Put it back? The horse has left the barn – Anthony

24. Dodgy Geezer says:

Look on the bright side. At least they did not adjust the ice extend downwards in 2007…

25. DaveF says:

Harold Ambler Sept 6 2013:
“You really can feel some of the people all of the time…..” (sic)
I wouldn’t advise it, Harold; you’ll get arrested.

26. george e. smith says:

Well it’s actually very simple. You see the earth has actually expanded, which is why the sea levels are going down, and when the earth expands, ice doesn’t expand, so the size of the ice relative to the blown up earth gets less.
Anybody who has ever studied the history of the world from the scratch marks on the main tunnel in the great pyramid of Giza, knows that those records of the history of the universe; which are precorded in those scratch marks, only make sense to historians if you know exactly where in the tunnel, the pyramid inch changes from one size to a new size.
So its the same thing with the JAXA ice; they probably adjusted their computer virus to bring it into accord with the pyramid inch.
So everything changes when it is more convenient.
I believe that at one time, the metre was exactly one ten millionth of the quadrant of the line of longitude passing through Paris; which is the way the French would do it.
And a nautical mile used to be the length of one minute of arc along the equator, making earth circumference exactly 21,600 nautical miles. Then they changed it to be exactly 1,000 fathoms, which is not 6,000 feet as the 4-H club lessons say, but is more like 6,076 feet which means a fathom is not 6 feet, but is 6.076 feet which is 6 feet and 0.912 inches; but then they decided that was too hard to remember so they changed one nautical mile to exactly 1852 metres.
Now I don’t know if that is the French metre that gose through Paris; but if not, they will change it again when it’s more convenient. Metrology is an exact science Climatology is not; so the pyramid inch is close enough for Climatology.

27. “You really can feel some of the people all of the time, as Lincoln said, but not all of the people all of the time.
To paraphrase Inigo Montoya, I Do Not Think He Said what you say He Said.

28. Owen in GA says:

There has always been a problem with interpretation of this data along shorelines in the arctic. There have been a number of times that visible images show clear water, but the ice extent showed solid ice along the shore which peters out a few tens of kilometers from shore. These corrections just clear up that issue. As long as they applied the same analysis technique to all the years in the dataset, it should actually be better data. If they didn’t then I would agree that it is shenanigans, but that doesn’t appear to be the case.

29. Jbird says:

They can adjust away all they want. Soon no adjustment in the world will be able to hide what will be occuring at both poles, winter and summer. All they will be able to do is postpone the inevitable.

30. BarryW says:

I concur on the change in extent. It’s just over 250k different. Interestingly, the melt is going to stop about the same time for both datasets (roughly two weeks).

31. Reg Nelson says:

I guess this means, for the foreseeable future, all published papers and presentations are only going to include data up to 2012, and sea level measurements will have to be adjusted up to account for the missing ice (water).

32. Pittzer says:

I’ve come to the conclusion that the biggest challenge Climatology faces is not one of pure science, it is one of engineering. The physical act of accurately measuring our atmospheric/planetary conditions and recording them properly befuddles us.

33. Mr Green Genes says:

I spotted it this morning (http://wattsupwiththat.com/tips-and-notes-2/#comment-1409330). I’ve been downloading their data for a long time so I compared all of it back to 2002. In general it seems to have made the lows lower (i.e. summer) and the highs higher. I agree with Anthony that the timing sucks but I also agree that if it actually means the data is more accurate then that is a good thing.
Interestingly, their long term historical data which goes back to 1978 (which I got by asking them for it) don’t appear to have been changed (yet), although the 1980s, 1990s and 2000s averages on their revised graphs are different, so I’m really not sure what’s going on there.

34. KNR says:

Never plan poker with these people , for you stand no chance against people with such ‘luck’ that ever adjustments , by lucky chance , ‘always’ result in them being able to claim ‘its worse than we thought ‘

35. Barbee says:

PEAK Season #’s look wonky. Didn’t you notice that when you did overlay?
I disagree w/ you-Ice was not lost at minimum-ice was gained at max.
& how could the both possibly be correct?

36. KevinM says:

UM…. did the 1980s average just get revised upward? How TF is that?

37. Man Bearpig says:

I think it must be pointed out to them that if they put the older plots along with V1 for the purpose of comparison with V2 then its like comparing apples with oranges. If they do not start from scratch or update the old databases then what they would show would be bordering on fr@aud.

38. stewart says:

Somehow this quote seems very appropriate: “Figures don’t lie but liars figure:.

39. Steven Hill from Ky (the welfare state) says:

Is anything real now? How would one know? What is real and what is fraud? I look for Obama care to start eugenics once again and someone will want to cleanse the world just like Hitler. We repeat the same history over and over. It all reminds me of the Nazi’s, this time they are world wide and through out society. Green Cars, Ban guns, Social medicine, Green Energy and total government control. Wake up people…..

40. Aphan says:

D’oh, others beat me to commenting on Harold’s quote. Darn! Was going to ask if that’s why Lincoln was such a popular president……:P

When I was a child my grandmother told me “A man with two watches cannot be sure what time it is.”
Later, in analytical chemistry class, my professor stressed the importance of making exact temperature measurements with a calibrated thermometer when calibrating volumetric glassware with the question “What do you expect to measure with a rubber ruler?”
Canonically, the measurements reported by the two protocols are incommensurable. Any effort to ‘harmonize’ the results is ad hoc and thus invalid.
It is a shame, they had a nice data set going…

42. Mac the Knife says:

Harold Ambler says:
September 6, 2013 at 9:46 am
You really can feel some of the people all of the time, as Lincoln said, but not all of the people all of the time.
Freudian Slip, Harold? I didn’t realize Lincoln was that ‘frisky’!
};>)

43. James at 48 says:

Version 2: Since we still can’t tell the difference between melt ponds and open water, and even get faked out at times by certain snow consistencies, what the heck, stop trying to winnow. Assume it’s all open water. DONE!

44. kramer says:

Of course the revision is for less ice:
Of course. They’ve revised ocean temperature data, they’ve adjusted land temperature data, and they even faked up to 80% of the ozone data.
I think Anthony should make a post that lists all of the climate science factors that were adjusted or revised by climate (and related) scientists and what the old and new results were and are. Some of them I am sure are valid such as the revised TSI data and it would good to list the valid adjustments as well.
Maybe it could be put it in the reference page (or pin it to the side) so it’s always easily accessible.
Just my two cents…

45. Steve Case says:

“I have overlaid the two graphs, and it looks like all of the sudden about 250,000 square kilometers of ice has disappeared.”
Why am I not surprised?

46. CRS, DrPH says:

Speaking of Abe Lincoln, I learned this today:
tycoon
PRONUNCIATION:
(ty-KOON)
MEANING:
noun: A wealthy and powerful person, especially in business or politics.
ETYMOLOGY:
From Japanese taikun (great lord or prince), from Chinese ta (great) + kiun (prince). Earliest documented use: 1857.
NOTES:
The word was used as a title for the shogun of Japan. Abraham Lincoln’s aides used the word as an affectionate nickname for him. Later the word came to be applied to powerful people in business.

47. davidmhoffer says:

I don’t have a big problem with this provided they use the same methodology across the entire data set, which it appears they have.
That said, the graphs pretty much track each other except for two rather sharp divergences in 2012. Small one at end of Nov and larger one at end of Dec. I’d be interested to know of any explanation as to why those exist.

48. I have been expecting the switch to the Japanese hosted replacement AMSR-2 from the stopgap US Navy WindSat data. They have been bringing systems up for some time.

49. Jeffrey says:

Anthony:
I’m more concerned about what seems to have happened to the winter maxima than the summer minima. Even though their technical changes seem to be about reducing counting of false ice, which should reduce extents, the winter maxima seem all to have increased substantially – more so for the 80’s than the others, and more for the 90’s than the 00’s. In fact, the 80’s totals seem to exceed the 90’s totals for the whole year by about the same amount. Suspicious, what?
But they have reduced the summer minima. Why should a change that reduces summer minima also increase winter maxima?
Again, suspicious, in that full-year ice totals now are shown decreasing steadily over the decades, better according with the warmist line than before.

50. Billy Liar says:

Harold Ambler says:
September 6, 2013 at 9:46 am
You really can feel some of the people all of the time, as Lincoln said, but not all of the people all of the time.
As Lincoln also said: “The worst thing about the internet is that not everything you read there is true”

51. rgbatduke says:

The new algorithm creates a downshift bias that is instantly apparent in the curves. In particular, it makes little difference in years with comparatively high sea ice at minimum, and a lot of difference in years with comparatively low sea ice minimum. This fairly obviously makes sense — if the entire arctic were ice coast to coast, the correction wouldn’t do anything at all. The more the coverage is marginal or broken up, the more opportunities there are for the correction to kick in.
The bad news for the new algorithm is that it is self-evident proof that their algorithm corrected or not is either terribly converged and hence inaccurate from the beginning or else has artifacts in it both before and after of unknown sign. There is no way a correction like this should have this large an effect unless coastal coverage is nearly fractal at minimum or unless there is a large systematic bias in the old way it was computed (which seems unlikely — nearly any averaging with sufficiently small pixel resolution for the average itself to be meaningful should not be seriously affected by repixellating the boundary. The two should scale like perimeter to area, that is, quadratically, and with anything like adequate pixellation only a small fraction of the pixels should be coastal in the first place. For example, if the entire water area were circular and the pixel size was $\Delta r$, the ratio of coastal pixels to open water (unaffected) pixels should be $2 \pi r \Delta r/\pi r^2 = 2r/\Delta r$. In general, the ratio of the coastal area to the interior volume should be proportional to $\Delta r / r$ where $Delta r$ is the size of the coarse grained area element (pixel) and $r$ is the length scale associated with the total area. For non-smooth surfaces the constant of proportionality might well be larger than 2, but it should not in general be as much as an order of magnitude greater unless the area itself is terribly resolved because $\Delta r$ is much too large to get meaningful results in the first place.
Let’s see if this is the scaling of the results above. At first glance this is unreasonable. To put it in simple terms, to lose 250,000 square kilometers from the perimeter of a 16 million square kilometers square with sides 4000 kilometers in length, you have to remove a strip of width 250,000/16,000 = 16 km in width from the whole thing. That is, we can estimate $\Delta r$ as being order of 10 km. Are the pixels used in the sea ice estimate really that large? That’s terrible resolution. But it is a lot worse than this — in order to lose this much, the area exposed to be lost has to be much larger, because not ever coastal pixel will suddenly convert from being covered with sea ice to not being covered with sea ice. In fact, if the previous resolution were close to adequate, the only places where one could lose pixels in a biased way is at boundaries between open water and sea ice right up to the coast, where the open water can reasonably shift a pixel one way or the other around the perimeter. If the prior granularity of ice on the entire boundary was one pixel (every other pixel sea ice and open water) and every sea ice pixel disappeared, it would only be half of the pixels that were formerly ice, so the pixel size would have to be at least twice the estimate above, some 30 km, and the entire coastal boundary would have to be covered by an alternating checkerboard of ice and open water 30 km to the side. Obviously this is almost certainly not the case — it would be surprising if the granularity were less than ten times this scale, exposing only 1/10th of the pixels to “sudden” conversion from sea ice to open water. Again, even if 100% of those pixels lost the conversion algorithm decision, this means we’re up to pixels hundreds of kilometers across where I would have expected them to be order of one kilometer across at worst. If the granularity of coastal ice-covered regions was order of as little as ten kilometers in size (where hundreds is a lot more reasonable) there is simply no way to lose 250,000 square kilometers of sea ice from any algorithmic conversion, even one biased to lose every contested pixel!
Unless, of course, my Fermi-estimate arithmetic sucks (entirely possible), but it is pretty simple stuff and enough to make me wonder if they’ve done sufficient common sense checking to ensure that their algorithm change produced a reasonable result or if the shift is the result of some artifact in the code. Or, maybe the pixels from which they make the estimate are huge AND there is a bias — that would do it too, but in that case they really need to include an error estimate per point in the original graph that is equally huge because the empirical resolution of the actual data is directly related to the number of pixels that can convert from a shift like this — the shift from a simple unbiased algorithm change SHOULD HAVE been on the order of the uncertainty in the curves themselves, and should not really have been systematic. To me it looks like the algorithm is taking lots of pixels that are square in the middle of coastal regions that are fairly solidly ice covered and just randomly flipping them to free in a way that would not make sense if one smoothed from the ocean side as well.
rgb

52. NZ Willy says:

I’ve always thought JAXA reports too low anyway. I prefer the DMI 30% chart, now sadly removed from Anthony’s Sea Ice page, but still at http://ocean.dmi.dk/arctic/old_icecover.uk.php . It looks like it’s reached minimum, maybe. The 30% chart is produced by DMI’s own people, unlike the 15% OSISAF chart which shows lots of spurious wobbles. Maybe DMI could be encouraged to keep it going.

53. Ted Clayton says:

The Land Expanded Mask, and Land Filter reference-images (dated 1996) appear to be an application of the well-known Convolution Matrix. These techniques are heavily used in image-processing, and DSP digital signal processing.
Very brief intro: http://stackoverflow.com/questions/2219386/how-does-a-convolution-matrix-work
As such, a close relative of what JAXA is doing here (convolutions are commonly used for “edge-detection”, in images) has already received intense scrutiny. The ups, downs and artifacts of the mathematical methodology have been extensively explored & characterized.
Indeed, the citation visible in the second Land Mask (image convolutions are also referred to as masks; the JAXA case may be a 2-D DSP function) is dated 1996 … so this has been around long enough to be a ‘known-known’, in the literature.
There is something resembling the Laws of Thermodynamics at work, with such digital operations. You can trade or convert one form of noise to/from another form … but entirely “disappearing” stuff you don’t like, usually breaks a fundamental principle.
The devil is in the specific side-effects of the specific manipulation employed.

54. And this, of course, is just an incompetence issue, nothing to do with intentions?

55. Greg Goodman says:

apparently both versions will be available until 30th Sept. But timing is indeed stupid. There was no urgency and blurring the lines just when everyone is focused on it not good.
It will lead to less confidence in JAXA.
They could hardly have not thought of this, so someone has a reason. Undoubtedly some loon at the Guardian will manage to compare this year’s V2 to last years V1 and claim another record breaking ice melt for 2013.
Then in two months when no one is interested any more there will be a discrete correction. (Or maybe not).
Alarmists now know the data and science is a lost argument so they are going for cynical misrepresentation and cash in politically before there’s time to correct it. eg 97% of lies…

56. Greg Goodman says:

“The Land Expanded Mask, and Land Filter reference-images (dated 1996) appear to be an application of the well-known Convolution Matrix. These techniques are heavily used in image-processing, and DSP digital signal processing.”
You can have “a” convolution matrix, there is not such thing as the Convolution Matrix.
While it does look a bit like a small 2D kernel what they are doing in not convolution (nor edge detection: gauss-diff kernel). They just take the lowest cell value if there is land in the frame.
All look rather kludgey, so good it’s being removed. Just should have been done later.

57. Ron C. says:

All the more reason to pay attention to the alternative method of estimating sea ice extent. The microwave sensors have always missed ice underneath melt water. National Ice Center (NIC) has the mission to ensure safe navigation of ships in icy water, and their analysts supplement the NASA products, with other data, especially satellite imagery and observations from vessels.
NIC charts show ice extent hovering around 6.0 M sq.Km for the last several days. The 8/10ths portion (packed ice) of ice extent is 4.6 to 4.7 M sq. Km. In 2012 the extent at this date was. 5.1 M, and the 8/10ths part was 2.8 M.
Over the past several years, the minimum has occurred on day 265 +/- 1 day (Sept. 21 to 23). For example, last year on Sept. 21, NIC showed ice extent at 4.2 M. Sq. Km., with the 8/10ths portion at 3.3 M.

58. kramer says:

@Jeffrey, yes your suspicions are confirmed:
Yeah, more BS adjustments that just ‘happen’ to go in their favor. I don’t buy it.

59. kramer says:

A blink comparator picture of version 1 and 2 would be nice.

60. Richard111 says:

Is it possible they hope this will prevent the coming ice age?

61. davidmhoffer says:

“@Jeffrey, yes your suspicions are confirmed:”
>>>>>>>>>>>>>>>
OK, now I have a problem with it. Thanks for drawing attention to the issue.

62. Latitude says:

They install two new things..that both reduce extent…and at the same time, jack up the past to make it look like more ice
…who’s crazy enough to think they didn’t do that on purpose?

63. NZ Willy says:

JAXA has been underreporting for a long time, I thought. I prefer the 30% DMI graph, which is honestly produced by DMI’s own staff, unlike the 15% OSISAF replacement. Maybe DMI can be lobbied to keep the 30% graph going.
The satellite data is much beholden to the orientation of its polarizing lens, which is turned to suit conditions at the pole of interest — causing the Arctic & Antarctic ice growth to appear to be anti-correlated.

64. Crashex says:

The winter maximums increase and the summer minimums decrease. All due to a land mask change? This change will further exaggerate the annual swings shown for the most recent years and “adjust” the minimums lower. The measurement methods and data analysis processes continue to make any current data comparison to historic data an apples vs. oranges endeavor.

65. rgbatduke says:

One other remark, after reading a few of the latter comments. Yes, the artifact could have been in the prior version, but even so the pixel resolution and bias have to be pretty staggeringly poor to have a 250,000 square kilometer (or more — Anthony is eyeballing and to my eyeballs it looks more like 300,000) effect.
The second comment is even simpler. Why doesn’t anybody ever bother to validate this at the local level? Surely one can afford to fly a plane along the coastline and take high resolution photos that allow the correct classification of every coastal pixel to be unambiguously resolved. In fact, the misclassification of water-covered ice can similarly be addressed by means of Monte Carlo sampling actual pixels from the interior volume. If I were writing ANY sort of classifier algorithm, I wouldn’t be just saying “oh, this algorithm sucks we need a new one” I’d be saying “lets get the actual precisely correct data and compare the algorithms available to see which one best approximates it”.
It doesn’t SOUND like this has been done, although I’m sure that there is a lot of literature out there beyond the mere announcement. If the algorithm has been verified by comparing its accuracy at actually getting the right answer as determined by looking at the crib sheet over a year or so, then while the disappearing ice is still puzzling and difficult to make sense of via scaling arguments, accurate as in agreement with direct observation is accurate as in agreement with direct observation. Accurate as in a supposedly “better algorithm” doesn’t mean anything at all without direct validation.
rgb

• Anthony Watts says:

@rgbatduke “…staggeringly poor to have a 250,000 square kilometer (or more — Anthony is eyeballing and to my eyeballs it looks more like 300,000) effect.”
My first eyball SWAG was 1/3 of a million, but I decided to be conservative- your estimate is probably closer.

66. Bill Illis says:

The changes increase the seasonal cycle of the ice extent.
The Feb/March maximum is up 300K to 400K (in all years but it varies some from year to year in terms of the change and the timing). And then the September minimum is lower by 300K to 400K (with 2012 having probably the biggest drop) .
It was not the right time of the year to bring this change in (but then, it would have been even worse doing in late-September for example).
They have been having problems with the data from the WindSat satellite lately which they were using and now they have just switched to AMSR2 satellite and revised all the data to what AMSR2 would have produced.

67. Friends:
rgbatduke said at September 6, 2013 at 12:46 pm

Accurate as in a supposedly “better algorithm” doesn’t mean anything at all without direct validation.

An important and irrefutable statement repeated here in case anybody missed it.
Richard

68. Ted Clayton says:

Greg Goodman @ September 6, 2013 at 12:29 pm protests:
“You can have “a” convolution matrix, there is not such thing as the Convolution Matrix.”
The relatively accessible Wikipedia note, in their intro: Computing the inverse of the convolution operation is known as deconvolution. https://en.wikipedia.org/wiki/Convolution
The relatively formal Wolfram also use “the”, extensively. http://mathworld.wolfram.com/Convolution.html
I’d have to see more of the JAXA literature/article, to say whether they are actually doing a matrix transform, or not. My first blush assumption was, they are.
It would be natural & effective, to use an edge-detection related transform (matrix) to deal with land-ocean interface effects.

69. EW3 says:

Hiding the incline !

70. mike says:

the timing makes perfect sense. Now the minimums for the summer will be lower so everyone (alarmists and recipients of grants) can report that the crisis is still upon us and therefore more money needed to stop catastrophe.

71. RACookPE1978 says:

RGB:
Adding to the “oddness” of this “correction” that you quantified by approximating the circumference is the following.
At this point in time – in the first weeks of September – the northern sea ice is at its minimum extent. As few km of the sea ice boundary as ever found during the year are now present, and almost all of the “borders” are ice-free completely. In fact, only the limited area around the Canadian Ellesmere Island channels, the Queen Elizabeth Islands, and a little bit more along the on the west side of north Davis Strait appears to be “touching” the coasts..
The entire coastlines of the Iceland, Franz Jospf Land, the Beaufort Sea, Chukchi Sea, Siberian Islands, Severnaya Zelmya, Svalbard, Siberia itself, and even almost all of the east coast of Greenland are completely ice-free.
So, if only 20%^ of the potential northern sea ice perimeter of a cap of only 3,600,000 km^2 is potentially wrapped around coastlines, how much wider must your “new and improved error band” grow? 3,600,000 km^2 of sea ice area (if a true circle) would only have a perimeter of 6700 km. If 20% of that length is now ice-bound against islands and between straits, then the 300,000 km^2 “growth” would be distributed in only a length of 1344 km, right?

72. george e. smith says:

Well I thought that everybody everywhere knows, that you can’t put the toothpaste back into the tube.
Take Coca Cola for example; well just “Coke” to most people.
It’s a formula that survived the great Pre-Cambrian extinctions; locked in a vault and maybe in the brain of just one person, who will be sure to pass it on to another, before croaking; like standing guard over the Holy Grail.
So some Ha’vid MBA genius comes up with a brilliant plan. Why don’t we change the shape of the Coke bottle; (well that in itself is going to screw up the whole of Optical Science; how the hell are we supposed to know now just what “Coke bottle” optics are any more).
But then we’ll come out with a different formula drink; everybody will love it; because we say so.
So we will call it “New Coke” or somesuch.
Well history records, that not everybody fell in love with “newcoke” Stuff tasted like hay that has already been once through the horse; ask Gail about that !
Well OOps, horse is out of the barn; genie is out of the bottle; toothpaste is all over everything; time to fire the MBA, and shovel this stuff back in again.
Well how are the yuppies supposed to know which one is real, and which one is faux.
Well we still have a ‘nother Ha’vid MBA; he says we label the original recipe “Classic Coke”, to distinguish it from the horse hay, once removed.
So outcomes “Classic Coke”.
Well we don’t want any “Classic Coke”. We want “Coke”; you know…Coca cola like we used to have. If it’s labeled “Classic Coke”, how the hell could it be the same as Coke, or else why would they not call it “Coke”. It’s gotta be different if they call it “Classic Coke”.
So now even the old geezer with the formula in his head, doesn’t have any idea what “Coke” is any more.
Well you see, these two excokemunicated Ha’vid MBAs are now washing test tubes at JAXA, and trying to recall from their Coke days; just how much ice are you supposed to put in that stuff ??

73. 3x2 says:

I have overlaid the two graphs, and it looks like all of the sudden about 250,000 square kilometers of ice has disappeared.

Why, one might believe that it’s IPCC report time again sometime soon.

74. Tom in Forida says:

rgbatduke says:
September 6, 2013 at 12:46 pm
“The second comment is even simpler. Why doesn’t anybody ever bother to validate this at the local level? Surely one can afford to fly a plane along the coastline and take high resolution photos that allow the correct classification of every coastal pixel to be unambiguously resolved.”
Of course one cannot go back to observe the 2012 coastline to validate whether the newer numbers are more accurate than the old.

75. wayne says:

” I agree. Does anyone keep track of these “one direction adjustments”? ”
Have you ever seen one in the opposite, in cooler or more ice direction? Not me. Why “keep track” when there are no opposites. This is one of the biggest reason I know this is not actual science, errors should always be symmetrical, both directions, you know, random errors, and this AGW “science” is not that, the real McCoy.

76. iamthor says:

Here are a few related gems to enjoy and to pass along . Looks like reality is biting a few behinds. And maybe Jack Frost too. See, if they could have waited only 16 more days it would have been totally ice free and this could have all been avoided.
http://www.powerlineblog.com/archives/2013/08/global-warming-expedition-foiled-by-ice.php

77. Auto says:

george e. smith says:
September 6, 2013 at 10:33 am
============
So nearly – good French red wine over the screen and keyboard.
Thanks!
Auto

78. rgbatduke says:

Of course one cannot go back to observe the 2012 coastline to validate whether the newer numbers are more accurate than the old.
No, so instead you run the new algorithm for a year or so while collecting data and then compare old algorithm and new algorithm to the actual data on at least a sampling basis. With anything LIKE a decent sampling, the issue would be closed — algorithm a would be better, b would be better, or it might well be back to the drawing board to work out c (this time with data in hand to play with while doing so). Perhaps they did this — I dunno. TFA doesn’t really say (that I saw, anyway).
rgb

79. rgbatduke says:

The entire coastlines of the Iceland, Franz Jospf Land, the Beaufort Sea, Chukchi Sea, Siberian Islands, Severnaya Zelmya, Svalbard, Siberia itself, and even almost all of the east coast of Greenland are completely ice-free.
Perhaps they weren’t classified as ice free in the previous algorithm? Although that seems as though it would be stupid misclassification of a distinct land/sea boundary problem, not a pixellation problem. That is the sort of thing that would make the kind of error that would drop the estimate by so much, if land glaciers were being misinterpreted as coastal ice or the like.
rgb

80. RACookPE1978 says:

rgbatduke says:
September 6, 2013 at 2:27 pm (replying to)
RACookPE1978 says:
September 6, 2013 at 1:17 pm
The entire coastlines of the Iceland, Franz Jospf Land, the Beaufort Sea, Chukchi Sea, Siberian Islands, Severnaya Zelmya, Svalbard, Siberia itself, and even almost all of the east coast of Greenland are completely ice-free.

Perhaps they weren’t classified as ice free in the previous algorithm? Although that seems as though it would be stupid misclassification of a distinct land/sea boundary problem, not a pixellation problem. That is the sort of thing that would make the kind of error that would drop the estimate by so much, if land glaciers were being misinterpreted as coastal ice or the like.

Ah, true, true.
But, at the point of maximum northern sea ice extent in March-April of 2010, 2011, 2012, and 2013 virtually ALL of these coastlines WERE covered with ice and snow on the land side, and surrounded by sea ice and snow on the sea side.
So,the “new” algorithm for sea ice extent designation by pixel MUST somehow either “convert” (at some day-of-year) a physical or designation change from a “pixel of land-covered-by-ice” to “a pixel of open ocean water NOT covered by sea ice,” The nice neat 3×3 theoretical matrices of sea ice and land ice in the story is missing a logic step of logical geography and time. Fill in 4x of the upper left hand blocks in the matrices above with 4x white, then 4x brown-covered-by-white, then 4x green-surrounded-by-white, then 4x green-surrounded-by-blue.

81. Ursus Augustus says:

V1->V2 is just fiddling at the edges really. The graph has bounced back about 50% of the perturbation from the mean of the past 30 to 35 years in only a year or two.
Now thats a comeback. Just more evidence of the utter hysteria created over AGW.

82. They are just expanding the extremes so the data from the next ten years as the global cooling sets in will still fit within the “normal” extremes. So the new larger extents out into the Pacific and Atlantic will still look “normal.”

83. Andreas says:

The same process as the surface station reorganization in the early 1990’s when the temperature measurement station numbers were drastically reduced and the temperature started rising rapidly…

84. Ian W says:

Does anyone know if any of these climate ‘science’ data repositories are ISO 9000-3 or ISO 8000 accredited? I thought that an ISO Quality Management System was a contractual requirement of receiving funds from government agencies. The behavior of these various repositories and climate metrics groups does not seem to be inline with the use of a QMS.

85. Eliza says:

Steve Keohane Adjusting sea edges NH ice,, so that’s what CT has been doing. Fortunately they could not do that for Antarctica and of course we can see the real picture

86. Jack Simmons says:

Why don’t they run both versions for a period of time; a year perhaps?

87. MattN says:

Why did the 1980s max jump so much? That’s rediculous…

88. Bill Illis says:

Here is a more clear chart of the changes between Jaxa’s new Version2 and Version1 (note this is probably about the fifth change in methodology from Jaxa actually).
The seasonal cycle has been amplified but the timing of the date which has the greatest change varies from year to year. (I’m not sure this is the final word on revisions).
http://s10.postimg.org/6sgr25au1/Jaxa_V2_Changes_Sep6_2013.png

89. Jimbo says:

On a related topic we need to keep a close eye on Professor Peter Wadhams of Cambridge University who is sure of something or other. Will he be our new Viner of the Arctic? Just 0, 2 or 3 years to go.
Independent – 27 June 2008
Exclusive: Scientists warn that there may be no ice at North Pole this summer
“…..It is quite likely that the North Pole will be exposed this summer – it’s not happened before,” Professor Wadhams said.”
Guardian – 17 September 2012
This collapse, I predicted would occur in 2015-16 at which time the summer Arctic (August to September) would become ice-free. The final collapse towards that state is now happening and will probably be complete by those dates“.
Financial Times Magazine – 2 August 2013
“It could even be this year or next year but not later than 2015 there won’t be any ice in the Arctic in the summer,”

90. But the historical was measured with JAXA 1, which means future measurements are not comparable to the historical. That does not sound like accuracy.

91. mogur2013 says:

Ursus Augustus says:
September 6, 2013 at 2:57 pm
“V1->V2 is just fiddling at the edges really. The graph has bounced back about 50% of the perturbation from the mean of the past 30 to 35 years in only a year or two.
Now thats a comeback. Just more evidence of the utter hysteria created over AGW.”
Yes, the good news is that it is a large comeback from last year. The bad news is that there is just as much hysteria on this site as most sites on either side of the issue. And just as many that have already made up their minds, and closed it to further evidence. There’s every bit as much paranoia, conspiracy allegations, and general wing-flapping here on this site, as any site dealing with this issue.
I respect Anthony’s initial presentation in this thread that the parameters are being adjusted at a seemingly inopportune time. And he gave credit to the fact that it may be an improvement overall to the data. But it has gone way downhill from there. Now, it is seemingly agreed to on this site that it is all a clever, premeditated ploy to distort the data for a political agenda. Anthony, really? You are egging on the fact that the adjusted data exaggerates this year’s ice melt, yet don’t qualify it with the fact that all melts are similarly reduced, and even say that you were being conservative in stating this year’s adjustment?
I haven’t even decided which side I am on. I used to be in the academic world and understand the egos of scientists, the drive to publish, and the value of shock to garner attention. I now see that this side is similarly handicapped. I guess I will have to keep looking to find opinions that are not stilted to either side.
I don’t really care if everyone here thinks that I am a troll, insane, stupid, or ‘a sheeple’ (that is a term for the closed mindedness on this site, btw). I just felt the need to say what I feel, and you can now get back to reinforcing each other’s paranoia and arrogance. I will simply keep seeking the truth, and I still respect Anthony greatly. I just wish he would stick to the real evidence and give up this moment of fame for a place in history where his battle for scientific reality proves damaging to all political hacks, not just the ones that disagree with him.

92. Go Home says:

Using calibrated eyeballs, it looks as if the mins got lower and the max’s got larger. So the net % change between max and min has now been MADE to be larger.

93. TomRude says:

One way or another Arctic sea ice will disappear… LOL

94. Gail Combs says:

Go Home says: @ September 6, 2013 at 6:07 pm
Using calibrated eyeballs, it looks as if the mins got lower and the max’s got larger. So the net % change between max and min has now been MADE to be larger.
>>>>>>>>>>>>>>>>>>>>
YUP. The better to SCARE the Chicken Littles… OH my the Ice is Melting, Its Melting!

95. David Ball says:

Incompetence or malfeasance, neither is acceptable.

96. TalentKeyHole Mole says:

Oh Dear!
[And the Band kicks in]
You’d be better off dead
Switchman’s sleep’n,
Train hundred and two
On the wrong track
And head’n for you.
[Choras; All Aboard!]
Drive’n that train,
High on Cocaine
Casey Jones is ready,
Watch yo’ speed
Trouble behind
And you know that notion,
just crossed my mind.
[Ending theme]
Trouble with you,
Is the trouble with me
Got two good eyes,
But you still don’t see
Come round the bend,
You know it’s the end
The fireman screams,
And the engine just gleams.
[Fini]
😀

97. Aussie Luke Warm of Ozghanistan says:

Mike’s Nature Trick lives on.

98. Louis says:

“You really can feel some of the people all of the time, as Lincoln said, but not all of the people all of the time.” Sorry Harold, that quote came from former San Diego Mayor Bob Filner, not Lincoln.

99. phlogiston says:

They are just taking the piss. What they are saying is, “you might have the facts and truth on your side, but we have the politicians, the MSM and the datasets in our hands, howjafeel?”

100. I don’t really care if everyone here thinks that I am a troll, insane, stupid, or ‘a sheeple’ says: at 5:58 pm
“I haven’t even decided which side I am on.”.-snip- I just felt the need to say what I feel, and you can now get back to reinforcing each other’s paranoia and arrogance.
——————-
Your indecision is not so apparent to this reader…

101. mogamboguru says:

No surprise here.
JAXA comes from the same people who for three years told the World that after the massive earthquake and Tsunami, Fukushima was finally safe…

102. Angech says:

Commentated at Lucia’s earlier on this. If they remove the ice at the sea land edge the overall volume should be lower at all times yet the winter maximums are larger. What gives? JAXA only running since 2002 so all adjustments prior must be very sus.

103. Angech says:

On a lighter note the recovery this year is still very evident and hopefully will continue and make a mockery of the warmest claims.

104. mogur2013:
Your post at September 6, 2013 at 5:58 pm
Is a very poor example of concern trolling.
I am sure you could have disguised your purpose much better if you had put more thought into your post before sending it. For example, you write this

The bad news is that there is just as much hysteria on this site as most sites on either side of the issue. And just as many that have already made up their minds, and closed it to further evidence. There’s every bit as much paranoia, conspiracy allegations, and general wing-flapping here on this site, as any site dealing with this issue.

Rubbish!
Whenever warmunists come here wailing about how Arctic ice will all be gone, I and others ask them why they care because the loss would have benefits (e,g, shorter and safer shipping routes) but no known harm.

That question we put to alarmists is not indicative of “paranoia, conspiracy allegations, and general wing-flapping”. And it is certainly not “hysteria”: it is an expression of being unconcerned. Furthermore, it is a request for ANY information which would justify alarmism and is the opposite of being “closed … to further evidence”.
As for having “made up … minds”, we know as certain fact that climate data are all frequently “adjusted”. The global temperature data change so often that it has reached the stage whereby if you don’t like the data today then don’t worry because it will be different next month (n.b. this is NOT an exaggeration). And the adjustments always alter the past to enhance the AGW-scare. If the adjustments were to correct discovered errors then they would not almost always enhance the scare: this is how GISS global temperature has been changed over the years
http://jonova.s3.amazonaws.com/graphs/giss/hansen-giss-1940-1980.gif
These data changes are NOT “paranoia, conspiracy allegations, and general wing-flapping”: they are documented facts.
And now we see large changes to Arctic sea ice data when Arctic sea ice loss is the final straw alarmists can cling to. Only a fool would not consider whether those changes are reasonable, justified and accurate.
But you come here and try to pretend that consideration of the Arctic data changes is “paranoia, conspiracy allegations, and general wing-flapping” of the same kind as promulgated by warmunists.
Your concern trolling is a classic fail, if only because it has encouraged my reply which explains the context of this thread to onlookers.
Richard

105. meemoe_uk says:

I was interested in sea ice a few years ago. I concluded that the teams that manage the data are the same ilk of people as Michael Mann and U of EA. The people who put Mann in his position would be crazy not to put similar agents in the satellite data teams. They’ve been finding excuses to lower the ice quantity for over a decade.

106. Mr Green Genes says:

Angech says:
September 7, 2013 at 12:17 am
Commentated at Lucia’s earlier on this. If they remove the ice at the sea land edge the overall volume should be lower at all times yet the winter maximums are larger. What gives? JAXA only running since 2002 so all adjustments prior must be very sus.

======================================================
I too (along with others) have puzzled over this. Maybe someone who understands the way the masking works (possibly rgbatduke who seems to have a good grasp of the subject) could comment on this thought I’ve had.
Is it possible that, during the winter months when a lot of the ice is up against land, the ‘old’ method of masking used to indicate parts of that ice as land, which has been improved using the new system?
Oh, by the way, as regards your last point, actually you can get data from JAXA which goes right back to 1978 if you ask them nicely. As I pointed out upthread, that data haven’t changed yet the Version 2 post 2002 data includes averages from the 1980s which have and I really don’t understand that.

107. Greg says:

” As I pointed out upthread, that data haven’t changed yet the Version 2 post 2002 data includes averages from the 1980s which have and I really don’t understand that.”
Apples and oranges. Understanding’s simple. It’s so that some bedwetter journalist-activist can use thier graphs to show the massive drop and keep the gravy flowing.
Later they’ll correct them like “oops” but the PR job will be done and Obahma will have used it to peddle climate change to the nation.

108. mwhite says:

Apparently this came from the mouth of James Lovelock
Referring to the arctic sea ice — “Ice is pure water so when it melts it becomes fresh water not salt water, which is lighter, so it floats on the surface of the sea and drifts downwards”
http://www.thegwpf.org/james-lovelock-global-warming-stalled/

109. SteveOak says:

They did something similar last year. Just as the (reported) ice level was to rise above the level of previous years, an ‘adjustment’ was made to the data that resuled in the (reported) ice level be reduced to a level not higher than previous years. This also resulted in the slope of the decrease from that point to the lowest point of the year having a decidely different shape than all previous years and the shape of the bottom of the curve being different from all other years as well.
I quite enjoyed calculus in college and have always had a keen eye for the comparitive slope of different functions. It is difficult to understand how the changes in slope I observed could correlate to a change of physical penomenon.

110. ferd berple says:

Such large changes from version 1 to version 2 indicates there is very high uncertainty in the result, for both version 1 and 2.

111. Patrick says:

In any kind of software versioning, in my experience, is that if you go from one whole version “number” to another whole version “number” there are usually significant, as well as and usually accumulative changes, included. Maybe not in “climate science”.

112. sunshinehours1 says:
September 6, 2013 at 1:59 pm
All the Jaxa differences are graphed here:
http://sunshinehours.wordpress.com/2013/09/06/jaxa-version-2-all-the-other-graphs-compared/
=================
WOW!!! These differences are unlikely to be a result of an unbiased algorithm. The algorithm has a much different effect the further back in time you go, suggesting that the algorithm is not constant over time in its effect. Reminds one of GISS adjusting the past to make it appear cooler.

113. Greg says:

http://www.ijis.iarc.uaf.edu/en/home/revision_v2.html
(ii) Modified Land-Ocean Mask
Version 1 used the land-ocean mask which is provided for SMMR and SSM/I, but for Version 2, due to the AMSR-E geometric precision improvement, we made new land-ocean mask which is adjusted for footprint size of the 18GHz band of AMSR-E (IFOV: 16×27km) and applied to the analysis of sea ice concentration.
Compared to Version 1, the sea ice extent of Version 2 has decreased.
===
So they are using a different and incompatible land mask for version2.
AMSR-E was launched on May 4, 2002, on NASA’s Aqua spacecraft. So all the pre-2002 data and their 1980s and 1990s averages are incomparable with the new processing.
If you go and dig they clearly state that there is a reduction, so why are they still presenting the data in the same file with the old averages.
This is just inviting misinterpretation and false conclusions. Comparable to Jones’ incarnation of “Mike’s trick” where he graphed different data together using the same colour.

114. Sleepalot says:

@ Sunshine hours, your graphs have different vertical axes: for the 1980’s 0.4 of difference = 26 mm on the screen, for 2013, 0.4 = 31 mm of screen.

115. Eliza says:

I reckon the turn has occurred and NH ice will now be normal or above for the next couple of 1000 years

116. Greg says:

“graphed ” should of course have been grafted. I frightened myself there, thinking I’d started using graph (a noun) as a verb.
Jones grafted different datasets together, applying a low pass filter after the graft to neatly blend the two together (Mike’s Nature trick TM). He then plotted the graph using the same colour, thus presenting the two as being the same thing.
Providing data in adjacent columns in the same file: initially decadal averages then individual years, implies that the they have at least been thoroughly cross-calibrated into a self-consistent time series.
This was previously the case for this same file but is no longer the case for v2.
That is a serious professional error at the least.
What they need to do is maintain v1 as long series and provide the better resolution v2 as 2002 onwards.

117. Ron C. says:

With the JAXA estimates of ice extent undergoing “adjustments”, it’s good to know that the National Ice Center is still on the job. NIC shows the smallest Arctic ice extent so far on Sept. 5, 2013 at 5.9 M sq. km., with the packed ice (8/10ths) portion at 4.7 M sq. kms. Since 2007, only 2009 and 2010 ran higher at that date.

118. Sleepalot I’ll fix the axis a little later today.

119. Greg says:

Ron C. says: “NIC shows the smallest Arctic ice extent so far on Sept. 5, 2013 at 5.9 M sq. km., with the packed ice (8/10ths) portion at 4.7 M sq. kms.”
Ron, I’ve seen you refer to NIC quite a bit but I can’t find a processed data “product” anywhere on NIC, just graphs and contour info.
Do you have a link to some usable data ? This looks like a good source.

120. Ron C. says:

@Greg
The main NIC products are the charts, and the numerical data are attached to them.
The Arctic Daily Ice Extent Archive shows graphs, and if you select a single year and month, the daily total ice extent number for each day will be displayed.
http://www.natice.noaa.gov/products/ice_extent_graphs/arctic_daily_ice_extent.html
To see a breakdown of that number you have to go to Products/Products on demand/Arctic Daily where detailed ice extent is shown in the two components: 8/10ths and Marginal Ice Zone. Unfortunately, to retrieve the numbers for any given day, you have to call up the chart for that day, using the Tools Box on the right side.
http://www.natice.noaa.gov/Products_On_Demand/pod.html
Perhaps researchers with credentials can access their database more conveniently, but I don’t qualify.

121. Ron C. says:

For those who want to know more about NIC ice charts:
“Arctic charts include information on sea ice concentration and edge position as well as (since about 1995)information on ice type. The charts are constructed by analysts using available in situ, remotely sensed, and model data sources. Data sources and methods of chart construction have evolved since 1972 resulting in inconsistencies in the data record; a
characteristic shared with most operational products. However the arctic-wide charts are the product of manual interpretation and data fusion, informed by the analyst’s expertise and by ancillary products such as climatologies and ice information shared by foreign operational ice services. They are therefore often more accurate, especially since the addition of synthetic aperture radar to data sources in the mid 1990s, than are the passive microwave derived sea ice data sets commonly used by researchers. This is especially true for ice edge location because of its operational importance. NIC provides charts free of charge on their Web site.”
“Often a wide marginal ice zone of 40% to 60% is not detected in passive microwave (this was noted anecdotally in earlier studies by the authors comparing passive microwave with ice chart and other analyses), and this appears to be the case here. Also, the NIC partial ice concentration for multiyear shows that thinner types are present in higher concentration near the edge, and passive microwave can fail to detect thinner, younger ice.”

122. Ron C. says:

@ Greg
I did a little more searching re your question, and found a source for a csv file.
http://nsidc.org/data/masie/index.html
It appears to provide ice extent numbers by region for the last 30 days. I don’t know where the archives are.

123. kramer says:

I didn’t read through this entire thread so this may have been said already. — I’m assuming the ice breaks up more in the summer and so could the new software be just discarding the broken up ice better?

124. george e. smith says:

Well what little I know about computer software, I always believed that computers do exactly what you tell them to do, except for occasional cosmetic rays going through your memory chips.
So I think it is incorrect to blame these differences on software; which after all merely tells the computer to do what you want it to do.
So if the results are different, then clearly it is the algorithms they changed, and not the software; in which case, they are no loger calculating what they previously were calculating, so when the change the algorithms, they should start the clock all aver again, as they clearly are calculating something different from what they used to calculate and plot.
Now I can see the software guys rewriting the computer code, to calculate the result more efficiently; but they should be able to do that anyhow, while still keeping the same algorithms they used to use.
So they need to come up with a new name for their graph, if they are using a different algorithm.

125. Argonaut says:

Global warming may be bad science, but the paranoia on this site is unbelievable. Like a pack of eighth-grade school girls. Or college profs after grants.
They’re being as transparent, the author agrees and the change is in the tenths of percent. Get on with some real topic.

126. mogur2013 says:

richardscourtney says:
mogur2013:
“Your post [is] a very poor example of concern trolling.
I am sure you could have disguised your purpose much better if you had put more thought into your post before sending it.”
Okay, you think I am trolling, disguising my purpose, and didn’t put much thought into my post. I simply refer to your own post, “we know as certain fact that climate data are all frequently ‘adjusted’. The global temperature data change so often that it has reached the stage whereby if you don’t like the data today then don’t worry because it will be different next month. And the adjustments always alter the past to enhance the AGW-scare.”
These data changes are NOT ‘paranoia, conspiracy allegations, and general wing-flapping’: they are documented facts. And now we see large changes to Arctic sea ice data when Arctic sea ice loss is the final straw alarmists can cling to. Only a fool would not consider whether those changes are reasonable, justified and accurate.”
I agree that we should consider whether they are reasonable, justified and accurate, but where is your documentation that they aren’t? I don’t disagree with you, I simply question your commitment to unbiased truth. My post that you chose to tear apart wasn’t directed at you, only the general tone on this thread. And I was happy to just leave this site to pursue less biased opinions, but your personal attack on me justifies at least an attempt at rebuttal. I am sure your ‘onlookers’ overwhelmingly approve your trashing of my post, but of course, that merely reinforces it.
What happened to honest dialog? The best to you in your endeavors, and I sincerely hope that the ‘experts’ are wrong.
A phony ‘concern troller’,
Gary Seymour