Of mountains, molehills, and noisy bumps in the sea-ice record

Note: This is a follow up post to this one: Claim: Antartica record high sea ice partially an artifact of an algorithm I’d actually planned to write a rebuttal like this, but a wonky T-1 data line took all my time today, so the honor goes to Pat and Chip – Anthony

Molehill of Antarctic Ice Becomes a Mountain

By Patrick J. Michaels and Paul C. “Chip” Knappenberger

In science,…novelty emerges only with difficulty, manifested by resistance, against a background provided by expectation. Initially, only the anticipated and usual are experienced even under circumstances where the anomaly is later to be observed. –Thomas Kuhn, The Structure of Scientific Revolutions (1962)

One of global warming’s “novelties” is that satellite measurements show the extent of ice surrounding Antarctica is growing significantly, something not anticipated by our vaunted climate models.

Thomas Kuhn would predict “resistance”, and today we see yet another verification of how stubborn science can be in the face of results don’t comport with the reigning  paradigm.  The paradigm, in this case, is that our climate models are always right and any counterfactuals are because something is wrong with the data, rather than with the predictions.

“Resistance” means that peer-reviewers aren’t likely to find much wrong with papers that support the paradigm (and that they will find a lot wrong with ones that don’t).  Further, the editors of scientific journals will behave the same, curiously avoiding obvious questions.

Perhaps as fine an example as there is of this process appeared June 21 in the journal The Cryosphere, which is published by the European Geosciences Union.  It is a paper called  “A spurious jump in the satellite record:  has Antarctic sea ice expansion been overestimated?”, by Ian Eisenman (Scripps Institution) and two coauthors.

As shown in our figure, the increase in Antarctic ice extent has been quite impressive, especially since approximately 2000.

Not so fast.  Eisenman et al. write that “much of the expansion [of Antarctic ice] may be a spurious artifact of an error in the processing of satellite observations” [emphasis added].

Wow, that would be really something, knocking down one of the glaring anomalies in global climate, and adding credence to the models.  Eisenman et al. note

In recent years there has been substantial interest in the trend in Antarctic sea ice extent…primarly due to the observed asymmetry between increasing ice extent in the Antarctic and rapidly diminishing ice extent in the Arctic (e.g. Cavalieri et al., 1997) and the inability of current models to capture this (e.g. Eisenman et al, 2011).

No doubt working from the premise that the observed increase in Antarctic ice just can’t be right, Eisenman et al. would appear to have finally verified that hypothesis.

Until you look at the numbers.

Then you are left questioning the review process—at all levels—relating to this work.

The key finding is that there was a processing error in the data.  Microwave sensors that are used to estimate ice extent (and also lower atmospheric temperature) wear out in the harsh environment of space, and new satellites are launched with fresh equipment.  But each one doesn’t send data with the exact same statistical properties, so a succeeding sensor is “calibrated” by comparison with an existing one.

Eisenman et al. found that there was a change in the intercalibration between instruments in December, 1991 when the data were reprocessed in 2007.  Apparently this wasn’t immediately obvious because there is so much “noise” in the data.

Indeed, Eisenman et al have located the needle in this haystack, showing the step-change between the two data sets:

Please take a look at the y-axis.  You will see that the value of the “step” change is about 0.2 times 106 square kilometers, or 200,000 square kilometers.

Wow, that’s a lot!  After all, Eisenman et al. tell us that this shift explains “much” of the increase in Antarctic sea ice.

Hopefully readers caught on before going this far.  If the reason that the shift was undetected is because the data is so noisy, how important can it be?  Now, have a look at the overall ice extent, shown in our first figure.

The y-axis is in millions of square kilometers.  The change since the turn of the century is about 1.3 million square kilometers, a mountain of ice  The step change is about 200,000, a molehill.   That doesn’t sound like “much” to us.

But, hey, if you don’t look too close—and we are sure are greener friends (or the reviewers) won’t (or didn’t)—you might believe that everything is ok with the reigning, model-based paradigm.  In fact there’s “much” that is wrong with it.

As Kuhn wrote, “Only the anticipated and usual are experienced even under circumstances where the anomaly is later to be observed.”


Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.

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July 22, 2014 7:35 pm

OK. If he’s right, the 2014 difference would be +0.85 million of square kilometers instead. Big whoop! Why does this garbage get published? (Oh……..never mind.)

Chris B.
July 22, 2014 7:36 pm

“But, hey, if you don’t look too close—and we are sure are greener friends…”
“…and we are sure OUR greener friends…”
FTFY. Good write up otherwise. Thanks guys.

mark l
July 22, 2014 7:45 pm

Bingo! Obfuscation, half truths, and scare mongering work well when opposing voices are silenced. The problem isn’t the facts, it’s the well known control of the message. The good news is it’s hard to hide the truth over time.

July 22, 2014 7:48 pm

Wouldn’t this then appear as a step around 1991? My eyes aren’t as good as they used to be, but I just don’t see it.

Mac the Knife
July 22, 2014 7:54 pm

Are you sure Michael Mann didn’t fudge the data for that 1st Figure? ‘Cause it sure looks like a full blown hockey stick comin’ on! };>)

July 22, 2014 7:54 pm

Also look at the time of the step change. December 1991, so that’s about the beginning of 1992. Now look at the first figure, the anomaly plot. This step change doesn’t seem to explain much at all. After all, this would not change the ramp we see starting about 2011, only the vertical position will be slightly adjusted. There is still a ramp, and the models still can’t explain it!
Furthermore, for the anomaly plot, since the step change occurs in the data from which the mean is calculated, the mean will change. So the actual change to the anomaly plot for the period since the step change will be less than 0.2 million sq.mi.

July 22, 2014 8:10 pm

Why is the second graph only plotted through 2005?

Bill Illis
July 22, 2014 8:15 pm

I dare you to find the step change in the data.

July 22, 2014 8:19 pm

Are we calibrating pixel level imagery at the base of this issue?
The devil is in the details.
What are those sensors referenced anyhow?
One might be surprised to know…

July 22, 2014 8:20 pm

One can’t help but feel that the purpose of this paper is to create a talking point: “There has been no recent sea ice extent records set”. No matter there appears to be no observable discontinuity. No matter that the bulk of the increase in sea ice has occurred long after the discontinuity was identified. No matter that the claimed discontinuity is small.

July 22, 2014 8:22 pm

Dang those annoying satellites… 🙂

July 22, 2014 8:43 pm

They believe the satellites when they measure the arctic, but then they don’t believe them when they measure the antarctic? Religious zealots.

July 22, 2014 8:48 pm

There is bias here. There is corruption. There is dillusion. But not a Scientific paradigm. Don’t use Kuln. It only excuses them.

July 22, 2014 8:50 pm

What about depth? Is Antarctic depth increasing with extent?

July 22, 2014 8:50 pm

After the Kaya identity nonsense, I really can’t be bothered to get in to another discussion here.
MIchaels and Knappenberger speculate about what the referees said and speculate about what their biases might have been.
But The Cryosphere publishes reviewer’s comments, so we can check whether the speculation is correct:
I’m sure that regulars at WUWT that will see some names they will have fun with.
Here are some extracts from what the reviewers said:
‘While the resulting trend will clearly be reduced in magnitude in comparison to v2, it may be that the trend is still statistically significant.’
‘I agree that you have made a compelling case for a discontinuity across the Decem- ber 1991 sensor transition. But I disagree that there is reason to suggest “the actual Antarctic sea ice cover may not be expanding at all.” … It seems to me that it is not unlikely the real trend is much less than believed at present, but even after adjustment the upward trend is still robust.’
‘This paper contains solid and important science and I congratulate the authors on their vigilance. It is certainly important to know that the uncertainties in the ice area/extent timeseries might be larger than thought … However, doesn’t Figure S5 in the supplementary material show that whatever the source of the Bootstrap issue, there is no doubt that Antarctic sea ice is increasing in both area and extent? … The clearly significant increases in all 3 datasets are not accurately reflected by the paper text, abstract, or title. … With the eyes of the climate change lobbies (on both sides) watching this debate, it is very important that papers’ titles, abstract, and conclusions accurately convey the facts. Very few journalists will check the content of the paper before reporting its title, and no-one should be expected to examine the supplementary figures of a paper.’
‘I would strongly advise sticking to robust statistical arguments, not arguments about what “should” be happening.’
‘This paper should be published and brought to the attention of the data-processing community so the problem can be properly addressed. The scientific community also needs to know about the discrepancy in Antarctic sea-ice trends revealed by this work.
In addition to the paper and the supplementary material, I have read four posted com- ments and one posted review of this paper. I agree with the central theme that runs through all five commentaries: the authors need to apply the v2-v1 offset (correction) to the v2 time series and calculate whether the resulting trend (1979-2013) is significant or not. Then they can decide whether the title of the paper is appropriate or not.’
I won’t be back to participate in this thread. The level of the comments so far indicates to me I wouldn’t get much out of it.
But have fun with Cowtan, Foster, Steig et al.!

July 22, 2014 9:07 pm

So lets say the ice extent was x in 2007 but should have been x – 200,000.
And in 2014 the extent was y but should have been y – 200,000.
The increase is still y – x.

July 22, 2014 9:33 pm

These whackos really do think we are all stupid.

July 22, 2014 9:40 pm

I skimmed the paper. I don’t think their claim is that there’s just a one time step change. If you read the paper, section 3 Results and discussion says:
…Version 2 has slightly lower values before 199 and slightly higher values afterward. This is associated with a substantial difference in the 1979-2004 trend
In other words, the step change identifies when the change took place, but also implies that it affects the entire record. In other words, the error (if there is one) shows as both a one time step change and ALSO as a change in trend across the record as a whole.
On the other hand, they also say they don’t know which one is correct. I note also that they only looked at 1979 to 2004. Given the time and effort that went into this paper, you’d think that they could have gone up until the current time? I mean, why drop the last decade’s worth of data?
Once you have the algorithm written to do this type of comparison, crunching the numbers right up until the end of 2013 is a few extra key strokes and a few seconds of super computer time. On that basis, while they may have identified an issue that suggests returning to a calibration exercise of some sort may be prudent, at the same time, I smell a rat.

July 22, 2014 9:45 pm

See Figure 1A in the paper. Quite clear that they are claiming a change in trend across the entire data set. BUT:
They’ve run Bootstrap v2 out to 2013 while they cut Bootstrap V1 off at 2004. Why wouldn’t they run Bootstrap v1 to the same point in time as v2?
Not only do a I smell a rat, I’m starting to think it is a really big rat.

Jim Clarke
July 22, 2014 9:46 pm

Thanks, JK. It sounds like the reviewers and commentators, aside from cheering the authors for their magnificent contribution to science, said much the same thing as Patrick and Paul: “It looks like the ice is still expanding and your headline and verbiage convey a different message that isn’t factual. You should actual be accurate when you report this.”
But the authors and the publisher ignored this sound advice and published the paper with its inaccurate message anyway! So what is the point of peer review? It seems like every scientist on both sides of the climate change issue is completely aware of the insignificance of this ‘finding’, but the authors ignore that fact, willfully misleading the general public and the MSM, building another climate change myth in the process.
Is there anything in the CAGW camp that is not built on a myth? We have the myth of constant relative humidity, the myth of the tropical hot spot, the myth of the hockey stick, the myth of the 97% consensus, the great myth of “…there is no other way to explain the warming of the late 20th Century…”, the myth of the highly tweaked (or is that twerked) global surface temperature record, the myth of heat hiding in the deep oceans, and so on. Now they are trying to build the myth of “It’s not ice…its an algorithm.”
Even a lousy theory will have a few facts that appear to support it, but the CAGW theory appears to be standing on myths ‘all the way down’!

Alan Robertson
July 22, 2014 9:47 pm

JK says:
July 22, 2014 at 8:50 pm
Nice flounce.

July 22, 2014 9:51 pm

OK, now I am looking at Figure 1B….
In this one, v1 is actually run out to 2013 just like v2. Now I see why they didn’t run the numbers all the way out to 2013 in Figure 1A. If you look at Figure 1B, it is clear that the trend of v2 is higher than v1. But, it also looks to me like v1 is accelerating faster than v2. Curiouser and curiouser…

Dave Wendt
July 22, 2014 10:07 pm

So they are claiming a significant step change at the end of 1991, but looking at the CT anomaly graph 1992 and 1993 seem to be mostly in seriously negative range (-1Mkm2 to -.75Mkm2) then moving just as strongly into positive anomaly in ’94 and ’95. I don’t have the ambition at moment to check to see if the calibration error they claim is legit, but if it is true, it will just add to the crescendo of other recent stories which indicate that the oh so “settled” science of the climate is grounded in baseline datasets that no one should be betting the rent check on, let alone the entire world economy. It would seem that everything we supposedly “know” about temperatures, ice, sea levels, weather “extremes”, and virtually everything else significant is based on data that is made up, estimated, adjusted, homogenized, fiddled, or just basically F’d up. It seems to me that before we sell the world down the river to save itself from the climate we ought have something a little closer to actual facts to hang our hats on.

Pat Michaels
July 22, 2014 10:28 pm

There is a reason I wrote that there were problems in the reviewing process “at all levels”. The authors who let this thing go had to have had one last look at it. But they signed off. They did this despite indications that running everything after 2004 would invalidate the result. The editor had to have had one last look at it, after seeing the peer reviews. But he signed off.
If I were Eisenman’s Department Chair, I would have him in the office tomorrow, to explain how he could publish such a misleading paper. I would also advise that this wasn’t a good idea for an Assistant Professor at a tier-one research university. I would have the coauthors subject to inquiry, also. If I were Copernicus, the publisher, I would have the editor in the office to explain.
And then I would seriously consider retracting the paper.

The Engineer
July 22, 2014 10:49 pm

The obvious question arising from this paper is – Why havn’t you done the same “correction” to the arctic sea-ice area, which may then be larger than previously thought ??

July 22, 2014 11:54 pm

So in my simple minded terms, this is saying that we thought that the sea ice anomaly was about equal to two times the the area of California plus Nebraska. But now we found that we were wrong about adding Nebraska.

July 22, 2014 11:56 pm

Very visible ice jump there has been not in 2000 but 2007. During the great solar minimum.

July 23, 2014 12:02 am
July 23, 2014 12:05 am

Maybe I am not getting the context of the Knappenberger context properly, but I would disagree, or not fully agree, at least.
A scientific explanation for anything is the best explanation for something at a given time in light of the then available evidence. – so things may change, but for what we take as granted at any point in time, there are usually good reasons. I had to think of the Neutrino controversy immediately when reading this, where for a while many people jumped the gun and already peddled, or at least liked the idea that neutrinos might be faster than light, after all. Now, these things were very well understood when the claim was made, so you would have been justified to book your money on the “novelty” being wrong – and so it was. There is no reason to be light on novelties, they will succeed, if there is meat to them.

Dr. Paul Mackey
July 23, 2014 12:09 am

I like this post – it has numbers in it. So you can see, and judge order of magnitude of any effect. The previous post “Claim: Antartica record high sea ice partially an artifact of an algorithm” – the press report – is noticeably dovoid of any numbers or indication of scale, apart from the graph, but has terms like “significant effect”. This hand waving non-specific reporting marks the press release as sensationalism and not science.

July 23, 2014 12:11 am

Jim Clarke says CAGW is built on myths:
Add in the fact that sealevel rise is around 1.6 mm / year according to a compilation of tide guage data, whereas with the GIA adjustment, the satellite number gets moved to 3.2 mm / year.

M Courtney
July 23, 2014 12:31 am

I like this quote from Steig’s review.

if the resulting trend is indeed still significant, as Holland suggests, then this needs to
be stated clearly. It doesn’t follow that the title needs changing though: it is correctly
posed as a question, and an important one.

The classic tabloid press trick of stating something you know is false (or unproven) as a question.
“Will eating lettuce give you cancer?”
“Have aliens visited us already?”
“Can we persuade you to be interested in this idle speculation?”
If ever proof were needed that Steig is a pseudoscientist… voila.

July 23, 2014 12:48 am

Expect activists on “climate change” to say from here on that “the denier meme of increasing Antarctic sea ice has now been “debunked”. ” Sigh…….

July 23, 2014 1:06 am

We should abandon observations and just use models. Models are so much better and fit into our post modern science world. After all we have those great Nobel Laureates like Michael Mann and Kevin Trenberth to show us the way. What could possibly go wrong!
I think I detect a flaw somewhere.

Ron McCarley
July 23, 2014 1:14 am

After noticing that the authors stopped in 2005, why do I feel that phase 2 of this study is just around the corner, that is, explaining away the remaining discrepancy? After all, they state that the 2007 and 2013 IPCC reports can’t both be correct, but the data shows that there was a distinct rise between these two reports. Am I missing something?

Stephen Richards
July 23, 2014 1:27 am

JK says:
July 22, 2014 at 8:50 pm
It’s crap and you know it. What purpose does this paper serve other than to open the door to another bunch of tax payer’s hard earned money. What does this contribute in return on investment for the taxpayer? It’s a piece of egregious spinning.
But glad to see to are leaving and taking your models with you.
à dieu JK.

July 23, 2014 1:55 am

This is a nice post, and nice to see the numbers all here too. I just skimmed the paper. It sounds like they’re talking about the 1979-2005 trend, not the change since 2000. When I fit the first plot in this post visually with a ruler during 1979-2005, I get a trend that’s not that steep. Maybe a few tenths of a tick during 25 years, say maybe 0.3, hard to do by eye. The step change in the second plot is 0.2 over the same time period. So it seems like it actually would have a pretty noticeable influence on the 1979-2005 trend, although not on the 2000-2013 trend. Am I missing something here?

Greg Goodman
July 23, 2014 1:56 am

It is true that 0.2 in 1.3 does not constitute “much of”.
Neither do they identify the problem, They present no evidence that it is the current value which is wrong. It is just an attempt to _suggest_ that the inconvenient Antarctic data is not reliable.
One would hope that the newer version of the algo is an improvement ( though I suppose that may be unwarrented in climate science ).
This raise the obvious question of whether a similar error is visible in Arctic data since that uses the same satellites and same algo. Curously they do not report on that. But of course they do not want to suggest Arctic sea ice data is unreliable since that has been a poster of AGW.
They are simply trying to “dis” the Antarctic data because it is inconventient. Unfortunately this makes the Arctic data equally unreliable but they avoid mentioning that.
The other obvious omission is “prevelent” argument. Bootstrap is “prevelent” but the other main algo is “NASTEAM”. They are clearly aware of the alternatives since they note BOOTSTRAP as “prevelent”.
The most obvious cross check would be to see what the NASA algo produced.
. Both of these steps are so obvious, especially in the face of the totally inconclusive result they are publishing, that it amounts to scientific malfasance.

charles nelson
July 23, 2014 2:34 am

Whilst some Warmists are frantically coming up with reasons why the increasing sea ice extent is happening; melting ice sheet/fresh water run off etc etc…other Warmists are saying ‘it isn’t happening’…..
Boys….we’ve got them on the run!

July 23, 2014 2:44 am

“By July 15, ice extent had fallen to within 440,000 square kilometers (170,000 square miles) of that seen in 2012 (the modern satellite-era record minimum) on the same date, and was 1.54 million square kilometers (595,000 square miles) below the 1981 to 2010 average. However, ice concentration remains high within the central Arctic Ocean, particularly compared to 2012.”

July 23, 2014 3:06 am

Since the Antarctic Ice Extent Anomaly hit it’s 35-yr record earlier this month, I’ve noticed many days of where the National Snow and Ice Data Center (NSIDC) satellite images were really funky.
One day there was a HUGE grey triangular pattern in the North-East quadrant of the NSIDC “Southern Hemisphere Sea Ice Extent with Anomaly” photo (which I interpreted as missing satellite data) but what struck me as strange was that this missing satellite data (which was probably about 500,000 KM^2) seemed to have been subtracted from the NSIDC’s Antarctic Sea Ice Extent Anomaly graph…
Then one day, all the Antarctic Sea Ice disappeared with only the orange Ice Extent mean line showing. Later, the sea ice extent reappeared, but it seemed to have shrunk…
Did anyone else notice this?
Now we get this paper saying that the Antarctic Ice Extent may (or may not) have faulty calibration issues….
CAGW grant grubbers love to adjust the data when it doesn’t fit their hypothesis… We saw this with the “new and improved” HADCRUT4 data and with all the shenanigans NOAA continues to pull with US land temp data (past temps lowered/recent temps increased).
Why is it “flawed” climate data is always “fixed” in a way that supports the CAGW hypothesis? Just given the law of averages, it would seem that at least occasionally, erroneous data would be unfavorable to The Cause… but, alas…

Alan the Brit
July 23, 2014 3:13 am

As with much, it wouldn’t mount to a hill of beans, as some of you in the Colonies might say! With our scientifically knowledgeable half-witted (polite) PDRofEU Climate Change Commissar, Ms Connie Heddegard, saying stuff like…..”even if Anthropogenic Climate Change Theory turns out to be wrong, isn’t it better that we use less of everything?”. The writing is on the wall for us, it demonstrates to me at least that it is a scam, a means to an end, an expediency, to justify oppression of the populous & suppression of truth……..something like to accuse Vladimir Putin of peddling from time to time, making them rank hypocrites, imho!

richard verney
July 23, 2014 3:14 am

First, i do not consider a discrepancy of 0.2 in 1.3 to be insignificant, or constitute ‘not much off’. Many here would argue that the failure to account properly for UHI leads to a 0.1 to 0.2 degC biasis in the ‘homogonied’ observed temperature anomaly rise of about 0.9degC. There is not an order of magnitude difference between these two .
Second, I consider that the post by JK was fair comment, and was a useful input. On the whole (apart from the point that M Courtney says: at July 23, 2014 at 12:31 am), the reviewers did not do a terrible job.
Third, the issue with the publication of the paper is what Pat Michaels says: at July 22, 2014 at 10:28 pm, but that is something rather different to the position that he took at the outset of the article, namely “Then you are left questioning the review process—at all levels—relating to this work.” So there is at least some merit in the comment made by JK.
Fourth, if there is problem with the data, as long as the original data is kept and available for all, I do not see that it is wrong to ‘correct’ identified ‘errors’ in the data provided that the full reasons for the correction are properly set out ,so that other may check and verify the legitimacy and the correctness of the correction and comment upon its implications.
Fifth, it does appear that the authors of the paper may well have identified a potential error, how that pans out is a different matter, as davidmhoffer says: at July 22, 2014 at 9:51 pm is alluding to.
Sixth, the main problem here is the somewhat misleading title and abstract (for which blame lies on the authors and editor) and the superficial way that the paper has been report in MSM, it being known, by those writing the paper, that it would get the superficial gloss that it has received in the press and thereby a short term PR success achieved.
Seventh, it still remains the case that Antarctic ice is expanding, and this does not fit easily with the AGW (let alone the cAGW) meme. Should, over the coming years, there be an expansion in Arctic ice then AGW will be ‘treading on thin ice’ indeed!

July 23, 2014 3:27 am
Crispin in Waterloo
July 23, 2014 3:55 am

To me the estimated 200k is high. Eyeballing the chart I see 150k max.
It so happens that the jump in the data coincides with a pronounced period of cold, or shall I say it in a way that indicates a continuum – cooling – that continued for more than a year. It was, very unusually, a period of drought in the middle on the Southern African 19 year drought/rain cycle. It should have been very wet at the time this “step change” was wrought.
The implication is that there is nothing wrong with the data, the instruments are calibrated correctly, there was a rise of a miserable 150,000 sq km in sea ice cover in a single summer and it persisted throughout the warming to 1997. Thereafter the extent continued to increase with an acceleration starting at the solar minimum in 2005.
The data is not ‘noisy’ it is ‘data’. The fact that the area of sea ice fluctuates from year to year does not make the data ‘noisy’. I am not convinced they have extracted a ‘signal’ from the ‘noise’. Even if the cause of that bump up is a calibration issue that went uncorrected (but who says the new reading is wrong and the old one right), it is 150,000 in 15,000,000 or 1% of value. That’s definitely in ant fokker territory, which is to say, insignificant.
The general claim is as spurious as the step change: if the popular notion that Antarctic sea ice is expanding is incorrect, show us the data, after correction, to 2013.

July 23, 2014 4:09 am

Alarmist use all the data that supports their conclusion. And adjust the rest.

Crispin in Waterloo
July 23, 2014 4:20 am

I just looked at the red and blue chart again. The Antarctic sea ice area expanded from 1987 to 1997 during which time the global temperature rose. There is no step change at all.
It is presently expanding at a faster rate than before. That is what the data shows. The rest is noise.

Paul Vaughan
July 23, 2014 4:24 am

Bad eye-sight??
“Please take a look at the y-axis. You will see that the value of the “step” change is about 0.2 times 106 square kilometers, or 200,000 square kilometers.”
It appears to be less than half of that.
Also, a very well-known natural step change happened around then.
Greg Goodman points out some steps around then:
Was there a change in what the satellite could see (caused by something else)?
Was there a natural step?
Whatever it was, it was less than 0.1.
It looks like 0.075.
(0.2 suggests bad eye-sight — or lack of carefulness.)

July 23, 2014 4:35 am

These Scientists should just launch a new satellite every year. That way they can explain away the ever increasing ice on the new satellite.

July 23, 2014 4:53 am

richard verney says;
“First, i do not consider a discrepancy of 0.2 in 1.3 to be insignificant, or constitute ‘not much off’.”
Something nobody seems to have considered yet: Ice area is measured against the average for 1979-2008 (30 years). Weare now told that the figures for 1992-2008, 17 of those 30 years is 200 000 km2 too high. This means that the average is also 17/30 x 200 000 = 110 000 km2 too high. So actually the net discrepancy is only 0.09 out of 1.3, or about 7%.
Perhaps not insignificant, but not much off either.

July 23, 2014 4:59 am

Um, that 0.2 looks to be based on the range of the peaks (about reaching the 0.1 line each side).
IMHO, we have two ‘wiggle ranges’ displaced to each side of zero. The “delta” between them ought to be the delta in the midlines – that is about -0.05 to +0.05 or about 0.1 (or 1/2 of the 0.2 you get from the range of the edges).
To be really accurate would take a stronger analysis than that with actual data…

Bill Lee
July 23, 2014 5:18 am

Data in the same sentence as climate models? Say it ain’t so, wait a jot, let throw some bones so I can predict a response … sheesh!

July 23, 2014 5:21 am

The range of the polar vortex at the height of 26500 meters. Visible lock over Australia and South America in the areas of stronger ionization by GCR (according to the Earth’s magnetic field).
The increase in the galactic radiation due to low solar activity.

July 23, 2014 5:26 am

“and we are sure are greener friends (or the reviewers)”
Should be
“and we are sure our greener friends (or the reviewers)”

July 23, 2014 5:44 am

That “rapidly diminishing ice extent in the Arctic” has been expanding for the last 3 years, and much of the decrease of the previous couple of years had nothing to do with global warming.

John Of Cloverdale WA, Australia
July 23, 2014 5:44 am

My apologies to the great Bobby Darin (RIP):
Now, there were two climate guys castin’ their eyes
Both in the same direction
You’d never guess that one little yes
Could start a new temperature collection.
Homogenization… that’s the name of the game!
And for each data set… it’s played the same!
Mother Nature is a clever girl
She relies on natural climate cycles
But Ya take two satellite sets with no cares
Pretty soon you got a sea full of rubbish.
Homogenization… that’s the name of the game!
And for each data set… it’s played the same!

July 23, 2014 5:58 am

is anyone else sick and tired of “the science is settled”….
..immediately followed by the past 30 years of science was wrong again

July 23, 2014 6:21 am

Assuming the the “step” represents an “error” is a mistake. The step might represent an error, or it might represent a true event.
We see almost identically shaped graphs in the transition from El Nino to La Nina events. Virtually identical – even using the same colors. It could well be that something happened in the Southern Hemisphere in 1992 that changed the long term pattern of ice extents.
However, because the authors of the paper were operating under the assumption that Antarctic Ice cannot be increasing because the models say it cannot, they completely overlooked what could have been a major finding in our understanding of climate.
In reality the paper is about creating a cheap headline to support a belief in models over observation. It is religion, not science.

Richard M
July 23, 2014 6:35 am

Once again, a comment from the owner of the data:
“The trend in extent in the Antarctic sea ice has been shown to be positive in different publications,” he said. “It is even more positive now than ever, and the Eisenman et al paper is providing a misinformation instead of a resolution.”

July 23, 2014 7:13 am

“The sea ice extent showed basically no trend in the earlier period because the inter-annual changes in extent were more uniform and the errors were large,” Comiso said. In recent years, he said, the longer record and better quality control has yielded a more trustworthy dataset — and one that shows more extensive ice cover.
“The trend in extent in the Antarctic sea ice has been shown to be positive in different publications,” he said. “It is even more positive now than ever, and the Eisenman et al paper is providing a misinformation instead of a resolution.”
Eisenman and his colleagues are now working to find the elusive error. It’s tougher than it seems.”

DD More
July 23, 2014 7:43 am

Notably, our 1964 estimate is substantially higher than the
estimates within the passive microwave record (Fig. 4). Even
within the wide range of uncertainty in the Nimbus I estimate,
the extent is higher than the monthly September average
of any of the years of the passive microwave record
(1979–2012). Even taking into consideration variation over
the month and using the highest and lowest daily extent values
during September, the Nimbus I value is clearly on the
highest end of the estimates. This suggests that the Antarctic
sea ice was more extensive during at least one year in the
1960s, and the small increasing trend during the 1979–2012
period may reflect long-term variability as the ice cover recovers
from a relatively low level back to possibly higher
1960s conditions.
The total Antarctic extent for September 1964 is estimated to be 19.7×106 km2,
From a paper making a manual investigation of September 1964 photos from the Nimbus I weather satellite.

July 23, 2014 7:50 am

Actually, it looks from the graph that the step change the paper claims to have identified is .02 x 10^6, not .2 x 10^6. It only goes from the bottom of the blue on the vertical dotted line up to the zero line. From there the red area increases steeply, but only AFTER the step change.
This change is taking place at a single point in time, correct, when it was decided to shift from the old satellite’s data to the new one’s data? Surely they didn’t average the two over some overlap period. If the step change is at one point in time, it is .02. x 10^6 = 20,000 sq km.

July 23, 2014 8:05 am

At 100% in September will be a new record of ice.

Two Labs
July 23, 2014 8:24 am

Didn’t read all the comments, so sorry if this has been pointed out already by another statistician, but I question whether the break shown at the end of 1991 in the second chart would qualify statistically as a “step shift.” If you look closely, there is a gradual increase between the beginning of 1987 and the beginning of 1993. The authors didn’t mention actually testing the data statistically for a shift. Did they?

July 23, 2014 8:28 am

It’s all about the grant money and justifying your job. You have to publish *something* to keep your job. Otherwise, where would Walter Meier and others be employed ?

Les Johnson
July 23, 2014 9:07 am

A supposed error in Antarctic ice? Nope, not according to the man in charge at NASA.
The climate scientist who maintains the data set, Josefino Comiso of the NASA Goddard Space Flight Center in Greenbelt, Maryland, says he is confident that the current data set is correct. Comiso says that he inadvertently introduced a mistake into the record — known as Bootstrap — at some point after 1991, but corrected it when he updated the file in 2008.
Comiso actually published his finding, and fixing, of the error. In other words, there is no exageration of antarctic ice extent.
Comiso, J. C. & Nishio, F. J. Geophys. Res. 113, C02S07 (2008)
Eisenman should have been aware of this, at the very least contacted Comiso, who “owns” the data.
All Eisenman has done, is to rewrite Comiso’s 2008 paper, which detailed the step change in 1991, and the correction in 2008.
Sloppy, sloppy work on Eisenmans, the reviewers, and the editors parts.

July 23, 2014 9:13 am

Clear typo. “Eisman” should be “EisMann”

Billy Liar
July 23, 2014 11:01 am

Greg Goodman says:
July 23, 2014 at 1:56 am
Two words of advice: spell checker 🙂

Ron C.
July 23, 2014 1:13 pm

Some might be interested to compare MASIE results with NOAA Sea Ice Index, since NOAA is a typical reference for Arctic Ice news. Like the Antarctic measures, NOAA uses only passive microwave readings, while MASIE includes other sources, such as satellite images and field observations.
For comparison, MASIE shows about 700,000 Km2 more ice extent than NOAA both at maximum and minimum. This is usually explained by microwave sensors seeing melt water on top of ice the same as open water.
For the years 2007 to 2013 inclusive, each year MASIE shows higher maximums than NOAA, on average 5% higher. In each of those same years MASIE shows higher minimums than NOAA, on average 15% higher. The melt extent is more comparable: NOAA shows an average annual loss of 70.5 %, while MASIE shows an average loss of 67.5%.

Chris B
July 23, 2014 3:27 pm

Hey, the Arctic and Antarctic Sea Ice Extent anomalies are the same today except polar opposites as to sign. Arctic is -1.204 million sq kms and Antarctica is +1.204, according to Cryosphere today.. Go figure.

richard verney
July 23, 2014 5:31 pm

tty says:
July 23, 2014 at 4:53 am
My point was overly simplistic in stating that a 15% abberation is significant (being approximately the odds of not surviving a round of russian roulette and many would not pull the trigger because they are concerned by a 1 in 6 event), when in practice it depends upon context. Planet Earth would be measurably different if there was about 15% more land, or about 15% more land in the Southern Hemisphere, so when talking about ice extent, I don’t consider it to be insignificant.
You point out that if for some 17 years the anomaly was ‘erroneously’ assessed too high, then a correction for that will have a knock on effect in the calculation of the 30 year base figure, but without studying the underlying data for the 30 year period, I would not want to put a precise figure on it, especially as I would have thought that the authors of this paper made that correction.
If what Les Johnson says: at July 23, 2014 at 9:07 am is correct, then this would appear to be accademic. If he is right, it appears that the authors of the paper made a big c*ck up.

richard verney
July 23, 2014 5:49 pm

Richard M says:
July 23, 2014 at 6:35 am
But will MSM carry such an article?.
Did you note the bias? Wind and currents could explain why Antarctic ice has increased, but no suggestion that winds and currrents could equally explain why Arctic ice has (at alarming rate) decreased!
The paper increasinly looks sloppy/gone off at half cock. It should be an embarrassment to those concerned in the writing, review and publication of this paper..

July 23, 2014 6:32 pm

” Chris B says:
July 23, 2014 at 3:27 pm
Hey, the Arctic and Antarctic Sea Ice Extent anomalies are the same today except polar opposites as to sign. Arctic is -1.204 million sq kms and Antarctica is +1.204, according to Cryosphere today.. Go figure.”
So, I guess that means there is no ice anywhere today? (the way the msm writes this stuff up, it wouldn’t really surprise me to see someone spew that, semi-seriously)
Seriously, though, that’s just too weird.

July 23, 2014 10:47 pm

The increase of cosmic radiation at the South Pole by more than 5%. Apparent increase in the ionization of ozone in the region of the magnetic south pole.

Greg Goodman
July 25, 2014 10:05 am

” Arctic is -1.204 million sq kms and Antarctica is +1.204, according to Cryosphere today.. Go figure.”…. Seriously, though, that’s just too weird.”
Weird like a stopped clock being bang on…. twice per day. 😉

Greg Goodman
July 25, 2014 11:08 am

Version 2 Summary
Changes to this version include:
Adjusted tie-points to be consistent with the AMSR-E Bootstrap algorithm
Reprocessed entire SMMR-SSM/I time series
Important: Because Version 2 is inter-calibrated with AMSR-E, it is not compatible with Version 1 of this data set. Users should acquire the entire Version 2 data set in order to update their time series. This product is also not consistent with the NSIDC-produced Bootstrap Product, the DMSP SSM/I-SSMIS Daily Polar Gridded Brightness Temperatures. For further information on Version 2 data processing, see Enhanced Sea Ice Concentrations from Passive Microwave Data.
5. Summary
The new data set on ice concentration using an enhanced Bootstrap Algorithm is the
result of a dedicated effort to generate a consistent and accurate time series of ice cover
data. The project includes the use of the AMSR-E data set which is currently the best sea
ice data available as the baseline for creating a consistent data set. The time series
generated consists of SMMR data from November 1978 to August 1987, and SMM/I data
from July 1987 to the present. Similar data from AMSR-E were also generated from
June 2002 up to the present. The relatively long overlap of AMSR-E and SSM/I data
So there is a new version of the algorithm ( version 2 ) the effects of which were studied in depth and reported in full.
Did Eisenman et al even bother reading the on line doc before writing this paper ?? It does not seem so.

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