Sea Ice News – Volume 3 Number 11, part 2 – other sources show no record low Arctic ice extent

This is my shocked face.

MASIE and IMS are the same thing – MASIE takes its sea ice data from IMS. So you can’t count it twice. It’s also misleading of you to mention MASIE / IMS without saying that it currently has 2012 as lowest on record for the time of year (lower than 2007) – it just hasn’t set a new record yet.
Finally, the melt season is not over yet. Will you put up a new post with equal prominence if/when MASIE also shows this year as a new record?
REPLY: MASIE/IMS – They are two different products, done by two different agencies, showing two different numbers. If they were identical numbers you’d have a point. As for showing it, actually I’ll do better than that, I’ll include MASIE in the WUWT sea Ice Page so we all can watch it. – Anthony

Don’t worry these figures will soon be adjusted to compliance with the “record low.”
/sarc

Why not ask an Eskimo?

I have said it many times on this blog before and I will repeat myself.
Please wake me up when something interesting happens at the North pole.
Perhaps finding the pot of gold at the end of the rainbow and even Santa’s grotto.
Otherwise the ice will do as the ice will do.
And there is no doing anything about it.
Kindest Regards

I’ll make a few points for clarification on the post above. First, MASIE and IMS are the same product. MASIE is simply a repackaging of the IMS data in easier to use formats. IMS is produced by the National Ice Center (NIC), using similar sources and methods as they use for their daily interactive maps. So all three of the examples provided are closely related and not independent measurements.
The passive microwave estimates all show a record low for the Arctic. These aren’t completely independent either – they all measure microwave emission, but there are difference sensors (SSMIS, WindSat, and for the first time AMSR2: http://www.eorc.jaxa.jp/en/imgdata/topics/2012/tp120825.html, which is pretty exciting), and there are different processing methods as well. There can always be potential errors in data, especially in near-real-time, so having multiple sensors showing consistency provides confidence that one sensor doesn’t have an error, which has happened from time to time. When it does, we go back and reprocess and correct the errors.
I worked at the National Ice Center for a couple years and have collaborated with them many times since, so I’m familiar with their methods and their focus. Their mandate is to map as much as ice as possible as accurately as possible each day and week in support of ships (particularly DoD ships) operating in and near ice-covered waters. They work hard on getting today’s data analyzed and then tomorrow they start over. They are not concerned with the past. If they can detect more ice today than yesterday, then they map it. If they lose a sensor, they do the best they can with what they have left. If they make an error, they don’t go back and correct it -it’s on to the next day. NIC doesn’t discuss climate or climate change because that is not their purpose and from my experience working there, they just don’t have the time – they’re focused on the here and now.
The charts are produced manually, so there is subjectivity in the analysis that we don’t have in our fully automated processing. This means that there can even be inconsistencies in adjacent regions if they were analyzed by different people.
They have created an archive of their weekly ice charts, which is archived at NSIDC: http://nsidc.org/data/g02172.html. There was some attempt to homogenize the charts (at least remove regional discrepancies) during the production, but they do not produce a consistent timeseries. MASIE, though it only goes back to 2006, has similar issues of consistency.
The folks at NIC do a great job at what they’re focused – navigational support. MASIE is an excellent data set and we at NSIDC find it very useful looking at specific details about the ice (e.g., is the Northwest Passage open or not), but the NIC products are not applicable to studying climate-scale changes.
Walt Meier
NSIDC
REPLY: Walt, respectfully, MASIE says 4.7, IMS says 5.1. If MASIE and IMS are the same product, how can they show different numbers? In your “repackaging” don’t you manage the IMS data to your methods in some way, resulting in a different end number? The differences in the 4.7/5.1 would seem to suggest you drop out some IMS data.
IF IMS products are only useful for navigation, why give a total extent value?
As for “usefulness in studying climate” no data set just a few years old can be useful for trends. They can however be useful for absolutes. For example you cite the new AMSRE2 data in that context. At just over 30 years old now, SSMI data used by NSIDC/CT is just barely above the threshold for a climate capable data set.
I suppose NSIDC would be a lot more believable to me if Serreeze wasn’t so focused on making pronouncements.
I’ll point out to readers that this year, WUWT, Meier, and Stroeve, all came to the same conclusion for September minimum in the ARCUS forecast – 4.5 million sqkm, something that suggests we aren’t as “breathtakingly ignorant” as director Serreze claims. – Anthony

Hi, Anthony,
i agree with you that the data gathering methodology is certainly suspect, but it is interesting to me that there are several sources catching this extremely low amount. I still would be surprised to see a “real” record low show even on the alternate sources.
But here’s the kicker… does that mean we’re a-roasting? I don’t think so. Global average temps are sliding now +.28C, which is not much at all, and the cumulative anomaly from January to July was just +.001C (Dr Ryan Maue, Weatherbell.com) which is basically nothing. Further, the history you occasionally post yourself indicates periods that were quite ice-free in the Arctic within the last century, and we had cold winters then and hot summers then, as now.
i think that there are certainly more questions than answers in reality. I think there is an assumption that Sea Ice in the Arctic has a direct relation to the severity of northern hemisphere winters, when most likely the opposite is true, since the rapid and deep cooling happens over land areas, and not over water. I am not sure how much heat loss takes place above the Arctic circle – I mean, sure it’s dark there during the winter – at least having no direct sunlight, but how does even solid sea ice compare in heat loss to land areas? I don’t know that – no one talks about that in “pop climate” circles…
I guess we’ll only really know when it’s all done. Keep up the good fight!

NIC products are not applicable to studying climate-scale changes? We use Al and Hansen for that part. 😉

c’mon folks, we need sensational headlines to go with the constant push for CO2 revenue-raising:
27 Aug: Washington Post Ezra Klein’s Wonkblog: Brad Plumer: Could a carbon tax help the U.S. avert the fiscal cliff?
With the United States facing the expiration of a slew of tax cuts in 2013—the dread “fiscal cliff”—there has been plenty of interest in offbeat tax-reform proposals. And one idea that a few economists keep knocking around is a fee on carbon emissions. After all, if we need to raise revenue, why not just tax global-warming pollution?
A new paper from the MIT Global Change Institute lays out how a carbon tax might work in practice…
According to MIT calculations, a modest carbon tax, on its own, wouldn’t get the United States close to that longer-term mark. It might make sense as a more economically efficient way of raising revenue. But the tax would either have to be hiked dramatically or combined with other clean-energy measures in order to make a significant dent in tackling global warming.
http://www.washingtonpost.com/blogs/ezra-klein/wp/2012/08/27/how-a-carbon-tax-could-help-the-u-s-avert-the-fiscal-cliff/

Paper finds Arctic sea ice extent 8,000 years ago was less than half of the ‘record’ low 2007 level
http://hockeyschtick.blogspot.com/2012/08/paper-finds-arctic-sea-ice-extent-8000.html

So, not being a trusting person … I went to the sources.
Masie is reporting 4.7 million square kilometres of ice, and NSIDC SII 4.1 million square kilometres. Nasie has 4km resolution, SII 25km resolution.
Back in 1963, surveillance satellites used in the Cold War could find an object 2 feet wide on the ground. Now the best we can do to monitor ice is either 25km or 4km resolution.
Anyway, let’s say that the 600,000 square kilometres of ice that the SII can’t see is less than its reported 15% ice extent. 7.5% for assumption. And, let’s say it is half the thickness of its lowest reported thickness of 0.5 metres. So, 0.25 metres thick (25cm or 10 inches).
So, 600,000 km2 X 7.5% is 45,000 square kilometres of ice 25cm thick. A square kilometre is 1 million square metres. So, 45 billion square metres of 25cm ice is 11.250 billion cubic metres of ice, or about a trillion cubic feet. Seems like a lot of missing ice to me! Compare: The BP oil spill in the Gulf of Mexico was 0.00078 billion cubic metres of oil (780,000 m3 of oil vs 11,250,000,000 m3 of “missing” ice). That’s only 14,423 BP oil spills of ice missing from the SII data set! The proven oil reserves in Saudi Arabia are about 27 billion bbls, which is about 4 billion m3 of oil or about 1/4 of the missing ice.
I go ice fishing on a lake in Canada every winter. It is 15 square kilometres and the ice gets close to a metre thick. So, 15 million m3 of ice in that lake is a rounding error in the missing ice world of the NSIDC. I’ll have to tell my buddies next winter to forget taking the ice auger, that lake is ice free according to the US government! We can just go and drop our lures and catch some fish!
Anyway, the MASIE site breaks down the ice by region. For example, the Beaufort Sea shows 300,700 square kilometres of ice, which is a huge drop from a couple of weeks ago. The steep drop indicates something other than temperature melting the ice, perhaps this “famous” storm. The Chukchi sea has its second highest sea ice extent in the most recent 5 years (which is what is graphed on the site). In contrast, Hudson’s Bay is showing its highest extent in 5 years at 67,400 km2 of ice. And the Central Arctic, which is where the thick ice is, is showing over 3 million km2 of ice extent. The Central Arctic is almost exclusively north of 80N. At 82.3N, the northernmost reported Canadian weather station shows a daytime high of -1C today, so it looks like the melting season has ended there. It was a whopping 3C over the weekend and below zero last week as well. The ice there is 4.5m thick, so it is unlikely to completely melt any time soon. November mean daily temperatures average -20C, and by the end of the first week of September Alert Nunavut won’t see anything exceeding 0C until the end of May.
But, isn’t this all to do about nothing? Natural variations in sea ice extent account for all of this. We only have 30 (or 43) years of satellite measurement of sea ice extent, during which time the instrumental record of temperatures shows a cyclical high, although for North America the 30’s were significantly warmer and parts of the 50’s were close. If ice extent gets under 3 million square kilometres, then it’s an event. Until then, no one should be excited.

“What was the Earth like before there was an Arctic?”
How do sea shell fossils exist at 2500 feet in the Oregon coast range?

I find it a bit odd of reports Arctic shipping took advantage of the worst Arctic storm in living memory.

There was less arctic ice for a period of over 400 years when the vikings were farming Greenland.
If this current situation continues for 400 years then I might start to get concerned.

No, it was meant for you here. hth.
REPLY: Hope this helps…uh no, there’s still no Tony T. nor forecast you refer to. – Anthony

Dave says:
August 27, 2012 at 4:09 pm
Why not ask an Eskimo?
————————————
That’s too easy and doesn’t require the expenditure of 10^7’s$ to support the apparatchik.

owl905 says:
August 27, 2012 at 5:15 pm
No, it was meant for you here. hth.
REPLY: Hope this helps…uh no, there’s still no Tony T. nor forecast you refer to. – Anthony
That’s about as swift as your IMS=MASIE responses. Go check your notes on how the funk in the Solar Cycles will put an end to the warming Tony. Or parrot another weak response, your choice.

REPLY: Ah, a smartass who speaks in tongues, noted for future bit bucketing. – Anthony

I think the neglect of people to talk about the Medieval Warm Period when talking about Arctic ice is sinful.

Here in the center of South America sub tropics 4C at the moment about -20C off scale it sure the hell is warming up!
http://wxmaps.org/pix/sa.00hr.html

On the discussion of the comparisons between PM sensors and NIC products, note that they’re talking about area (I.e., weighted by concentration). There is a well-known bias in PM area estimates due to surface melt and weather. However, this is much less of an effect for extent, which is a simple ice or no-ice threshold. There can sometimes be larger discrepancies in rare cases like this year with the sparse ice regions, but PM and NIC extents generally are pretty close, especially when accounting for the fact that NIC maps all ice.
Walt Meier
NSIDC

Just for grins, lets look at this situation the way scientists would have 35 years ago, before climatologists became perpetual government lobbyists mostly interested in trying to secure their grant-dependent paychecks (and when I was in graduate school). We have now a way to measure ice extent (NSIDC) that goes back a number of years, and for the last several years there is also a new and different way to measure ice extent (MASIE). The two methods disagree to the tune of around 0.6/4.1 or 0.6/4.7 — depending on what is chosen for the denominator — say, approximately, 13% to 15%. This is great, because now we can go back to all the past NSIDC measurements and put 13% to 15% error bars on them. Not only that, we can compare the MASIE and NSIDC measurements over the last few years and see whether their difference is mostly random, mostly constant (which suggests bias) or somewhere in between.
Of course scary ice-shrinkage graphs are going to look a lot less frightening with these sorts of error bars attached to the data points, so there’s no point holding your breath waiting for the science establishment to produce them …

The NSIDC methodology seemed good enough for the http://wattsupwiththat.com/2012/06/01/sea-ice-news-volume-3-number-6-sea-ice-outlook-forecasting-contest-for-2012-is-online/ with the “4.9 million square kilometers” for the ARCUS submission.
REPLY: But we aren’t allowed to compare to others and ask questions. Check -A

The melting is great news, scientifically. This is the first time so much melts since we’ve had satellites to measure ice. So this means a wealth of interesting data to study in the years to come.

Tez says:
August 27, 2012 at 5:13 pm
“There was less arctic ice for a period of over 400 years when the vikings were farming Greenland.
If this current situation continues for 400 years then I might start to get concerned. ”
Greenland, especially southern Greenland where the farming Vikings were, is not part of the Arctic Ocean where the floating ice (or lack thereof) being discussed in this post is located. I don’t recall reading anything about floating Arctic Ocean ice during the Vikings-farming-Greenland period. I would greatly appreciate a link.
————————————
Tez, you must be a long-lived alien for I’m fairly certain none of the rest of us expect to be around to share your concern in 400 years.

Jean, Mann’s mood is not described by any witness. It is interpreted by Anthony.
Regarding the fascination with sea-ice for warmists, it’s a two-edged sword.
On the one hand it is an indication – observable evidence – of what they fear and lament. It bothers them.
On the other hand, it is, for them, an easily observable, fast-moving metric that may wake the populace to the anti-CO2 emissions cause. It is also a thumb in the eye to skeptics that have been promising that 2007 was the year that would begin to see sea-ice rebounding back to previous levels; that recovery is nigh.
And I think for them there is a kind of morbid fascination with watching a train wreck in slow motion. Certainly for myself, the idea that I could see a North Pole free of ice within my lifetime – well, I’d be dead if it didn’t energise me in some way. This is an event that won’t have occurred in the history of human civilization, and perhaps not for millions of years, and it is on a grand scale. Rarer than a blue moon, and as big as a continent: the decline portends an awesome event, regardless of belief or otherwise in AGW.

Walt Meier :
“There may be some slight differences in numbers….”
If Walt thinks 0.4m KM is a “slight difference” then he should not have a job in a scientific discipline.

I never understand the warmists. On the one side they say they are alarmed by the “catastrophic” global warming, but at the other side they are happy that the polar ice is melting. Now, what do those guys really want: warming or cooling?
DISASTER !!!!

mortis88 says:
August 27, 2012 at 4:16 pm
ummm, Philip, “begging the question” means that there is an obvious, unanswered question. Wiki is a horrible reference tool
My tuppence ha’penny worth, Pocket OED:1925, Petitio principii, begging of the question, from the Latin, begging of the principle! A classic example is as said previously, upon the discovery of the so called “hole” in the Ozone Layer, “how do you know it hasn’t always been there?” An important question so far unanswered in 50 years! Current data suggests this is a regular oscillating occurrence. Then again awkward questions of detail are best swept under the carpet, better to creat panic & fear instead, sarc off!

D. Cohen says:
August 27, 2012 at 8:19 pm
Of course scary ice-shrinkage graphs are going to look a lot less frightening with these sorts of error bars attached to the data points, so there’s no point holding your breath waiting for the science establishment to produce them …
————————————–
The NSIDC Arctic Ice Extent graph at the top of this post normally has error bars for the 1979-2000 average included on the graph.
http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png
For some reason Mr. Watts prefers to remove the error bars when he shows the graph in WUWT.

The BBC ran this yesterday and interviewed some Oxford ‘expert.’ He claimed that ‘they’ had forecast this for years. He also predicted zero ice in summer at sometime in the future. Where have we heard this before? However, there was no mention of differences between the various survey methods.

Surely the main point here is not the absolute quantity of ice but the change over time? As long as NSIDC uses the same method of measurement now that it used in 2007 and back to 1979 it is perfectly correct for it to say that NSIDC’s measurement of the extent is at NSIDC’s lowest level since NSIDC started its index.
In which case it really does not matter what measure you use provided it is consistently the same. The “absolute” figure is only really important when comparing methodologies (or when determining the end point when the ice has all finally disappeared). For instance it is possible for there to be a record low in extent without there being a record low in area – as that is dependent on how spread out the ice floes are.
Trawling the different measurement regimes to try and find a figure that is higher than NSIDC’s and then say “there, I told you the sea ice is not at its lowest extent” is just blatant bad science, statistics and journalism frankly.
You are comparing apples with oranges and saying “there, I told you fruit are red not orange”.

This might be good for the skeptic cause again as the warmists totally exaggerate and are caught out once again re: other graphs and probable increase next year ice extent NH back to normals etc. The whole discussion is actually pointless as global temperatures have NOT increased since 2002 and as you point out Antarctica has been above anomaly most of the time so no correlation whatsoever..

I am suffering from AOS.
Acronym Overload Syndrome
Please provide a UGOAART.
Useful Glossary Of All Acronyms Referred To.
.

From Bill Irvine August 28, 2012 at 5:17 am:

Please provide a UGOAART.
Useful Glossary Of All Acronyms Referred To.

Go to toolbar at top of any WUWT page. Go to “Resources”, click on “Glossary”.
If the acronym is not there, you can ask for it with the comment box below.

With regard to previous sea ice around the arctic, I remember reading a book called 1421 a few years back which told of a huge Chinese fleet which explored the world at that time. Some of the claims are more believable than others but IIRC among them is that a remnant of the fleet sailed up the west and round the north coast of Greenland and managed to produce maps at the same time.
Obviously that is not possible today, but appears to have been then, perhaps more evidence of the medieval warm period and, if true, would certainly have allowed farming in southern Greenland.
If nothing else it was an interesting read, especially the discovery of America pre-Columbus.

@stephen richards says, August 28, 2012 at 1:10 am

I never understand the warmists. On the one side they say they are alarmed by the “catastrophic” global warming, but at the other side they are happy that the polar ice is melting. Now, what do those guys really want …

Control [in a variety of guises].

The grey bar in the NSIDC chart is the standard deviation (x 2), NOT ‘error bars’. A standard deviation shows the spread of data around the mean. Error bars show the range of possibility for an estimate.
That NSIDC show 2 standard deviations from the mean is a testament to how much the ice coverage has receded. Right now, the NSIDC 2012 value is 7 or 8 standard deviations away from the 1979 to 2000 average. In purely statistical terms, this is a huge departure.

This is anecdotal, but I overflew the Arctic Ocean many times during the mid-1960s. One year, 1964, I spent about 35 days, from August into early September, flying sorties out of Eielson Air Force Base, Alaska. Back then, there was much more sea ice on the Arctic Ocean than the satellites depict for current times. Of course, back then, there were no satellites monitoring sea ice on the Arctic Ocean. On sorties we flew out toward Novo Sibersk and Severnaya Zemlaya the ocean was covered in sea ice from a few tens of miles off shore from Point Barrow. We could see leads in the pack ice, but it was pretty much solid by the time we got around 100 NM off shore. By the time we flew our last sortie, in early September, the sea ice had noticeably move in toward the shorline at Point Barrow, maybe no more than a mile or two off shore. The day in the first week of September, when we departed Eielson AFB for home, a heavy wet snow was falling.
Now, I’m citing all of this from memory, but in that period much or North America was experiencing very cold winters. I am certainly not a believer in human caused global warming, but over seven decades of casual observations, The trend has been from colder winters to, frequently, milder winters. BTW, I am old enough to remember the infamous Blizzard of ’49. It came over the area I lived in as freezing rain severe enough that it downed power lines and broke many, many trees. It was close to a week before power was restored. Back then we kept warm with coal-fired furnaces and burned candles for light. The ice was a long time melting.

Philip Bradley says:
August 27, 2012 at 3:41 pm
Anthony, some one pulled me up for the mis-use of the phrase ‘begs the question’ a few weeks ago.

You should have highlighted that someone’s pedantry.

Theo Goodwin says:
August 27, 2012 at 5:07 pm
Sorry, it means arguing in a circle.

Here’s what one researcher found:

For example, if we search the NYT index for recent uses of “beg the question”, we find that out of the first 20 hits, 15 use “beg the question” to mean “raise the question” — and of the five that don’t, four are usage articles berating people for misusing the phrase!
Turning to the broader and more erratically edited range of material indexed by Google News, a check of the first 50 of the 127 current hits for “beg the question” turns up 49 instances meaning “raise the question” and one lonely usage column . . . which makes this amazing assertion:

But for me, all this raises a more important question. You see, for all the people I’ve heard bemoaning others’ misuse of “beg the question,” I’ve never actually heard someone misuse it.
So all the friends who told me I should do a column on “begs the question” because the term is so widely misused — well, it looks like those people were begging the beg-the-question question.

In other words, nobody (or hardly anyone) uses the term to mean “assuming the conclusion”. This is probably because of the terrible, awkward, and outdated translation of this meaning into English.
My advice to you is to let it go. The new meaning is well understood by everyone – even you. You only cause confusion and problems when you comment on it.

Anthony, I’m afraid you failed to read the manual. “While operational analyses are usually the most accurate and timely representation of sea ice, they have errors and biases that change over time. If one is interested in long-term trends in sea ice or how it responds to changing climate forcing, generally, it is best not to use an operational product, but rather one that is consistently produced and retroactively quality controlled. The NSIDC Sea Ice Index monthly ice extent, and the satellite passive microwave data sets upon which it is based, is one example. The Sea Ice Index gives a daily image of extent as well as monthly products. However, these daily images are not meant to be used for climate studies or for inferring anything longer than seasonal trends. Satellite data are not quality controlled quickly enough; and for reasons explained in the Sea Ice Index documentation, the daily ice edge position can be off by tens of kilometers or more from the ice edge that an analyst would draw. Reasons include known errors in thin ice detection, bias in summertime concentration estimates, and the relative compactness of the marginal ice zone. See Partington et al. (2003) for an assessment of operational versus satellite-derived ice concentration.”
You are using this product in a way specifically called out by NSIDC as incorrect and fallible.

Norman says:
August 28, 2012 at 8:24 am
Over at Sketptical Science Daniel Bailey posted a map of Arctic ice in August of 1938. It seems the sea ice extent has been dropping rapidly the last few years. From his souce of the map you can look at sea ice extents for many years and various months.

And I can show maps from 1600 showing open water. Doesn’t mean it’s accurate.

From barry on August 28, 2012 at 7:33 am:

The grey bar in the NSIDC chart is the standard deviation (x 2), NOT ‘error bars’. A standard deviation shows the spread of data around the mean. Error bars show the range of possibility for an estimate.

Maybe terms got blurred over time, during the age of quick spreadsheet graphs, but the short Wikipedia Error bar entry says something somewhat different:

Error bars are a graphical representation of the variability of data and are used on graphs to indicate the error, or uncertainty in a reported measurement. They give a general idea of how accurate a measurement is, or conversely, how far from the reported value the true (error free) value might be. Error bars often represent one standard deviation of uncertainty, one standard error, or a certain confidence interval (e.g., a 95% interval). These quantities are not the same and so the measure selected should be stated explicitly in the graph or supporting text.

I’m trying to figure out exactly what they are showing. Two standard deviations is 95%, they’re working with daily measurements (smoothed with a 5-day trailing average), it looks like they’re showing the range that 95% of that day’s measurements fall in. But the reported measurements have an amount of uncertainty to them. Is that worked into those bars as well?

“Ask an Inuk”, please, or ‘one of the Inuit’ (the collective noun). You could also ask one of the Yupik or Aleuts. “Eskimo” (people who speak a different language) is considered by many to be an epithet.
“In Canada and Greenland the term Eskimo is widely held to be pejorative and has fallen out of favour, largely supplanted by the term Inuit. However, while Inuit describes all of the Eskimo peoples in Canada and Greenland, that is not true in Alaska and Siberia….Alaskans also use the term Alaska Native, which is inclusive of all Eskimo, Aleut and Indian people of Alaska…”
– http://schools-wikipedia.org/wp/e/Eskimo.htm

So when there is a number of measurement available, the one chosen is that which gives the most alarming results, not that which is likely to be the most robust. A bit like using the latest version GISSTEMP to measure the global average temperature change.

From Mark Harmon on August 28, 2012 at 8:49 am:

You are using this product in a way specifically called out by NSIDC as incorrect and fallible.

Strange, some scientists don’t pay heed to NSIDC’s admonishments. For example, on PIOMAS’ home page it says:

For the ice volume simulations shown here, sea ice concentration information from the NSIDC near-real time product are assimilated into the model to improve ice thickness estimates and SST data from the NCEP/NCAR Reanalysis are assimilated in the ice-free areas.

Yet you follow that NSIDC link and it clearly says:

These data are not suitable for time series, anomalies, or trends analyses. They are meant to provide a best estimate of current ice and snow conditions based on information and algorithms available at the time the data are acquired.

So PIOMAS uses data that is stated as ‘not fit for purpose’, that is incorporated into the PIOMAS model’s “sea ice volume anomaly” results, presented as a time series, with trend analysis. Yet alarmists everywhere are quite happy to report the PIOMAS figures as accurate and fully scientific.
Really, you have to figure out what NSIDC product is suitable for analyzing extent (or area) trends. NSIDC says to not use their daily Sea Ice Index numbers, use monthly. And even then, there are caveats.
http://nsidc.org/data/docs/noaa/g02135_seaice_index/

Data Sources
All Sea Ice Index images and data are derived from daily or monthly gridded sea ice concentration that come from two sources: The Near-Real-Time DMSP SSM/I-SSMIS Daily Polar Gridded Sea Ice Concentrations (NRTSI product) data created at and distributed from NSIDC with data set ID NSIDC-0081 and the Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS Passive Microwave Data (GSFC product) created at the Goddard Space Flight Center (GSFC) and distributed from NSIDC with data set ID NSIDC-0051. The NRTSI product is available at a daily temporal resolution, and the GSFC product is available at a daily and monthly resolution.
…
The GSFC product is more tightly quality controlled; and for this reason, NSIDC considers it the final authoritative SMMR, SSM/I, and SSMIS passive microwave sea ice concentration record. However, NSIDC does not receive this product from GSFC until roughly a year to a year and a half after the data are acquired. We use the NRTSI product to fill the gap until the final GSFC product data are available. NRTSI data are processed at NSIDC like GSFC data are processed at Goddard, but the brightness temperature data source for the two products is different along with other small differences. (…)

Elsewhere it is mentioned that NRTSI numbers are replaced with GSFC numbers.
So don’t try to infer much of anything from the daily Sea Ice Index numbers as there’s too much uncertainty. (Heck, you have to wait several days after they come out for them to be “set”.) Monthly is better for just about anything.
But in either case, you might have to wait until the numbers are more than 18 months old to say anything definitive, as the Goddard numbers are the final say. Maybe quite a bit longer, the NH daily GSFC-only final file (versus the NRTSI-only “provisional” file) ends on the last day of 2010, nearly 21 months ago.
But what if you needed the most accurate reliable info on the sea ice now? Like if you wanted to a quick spot check on a report of tremendously low ice? You’d use MASIE.

From manicbeancounter on August 28, 2012 at 11:57 am:

So when there is a number of measurement available, the one chosen is that which gives the most alarming results, not that which is likely to be the most robust. (…)

Oh, you should love the latest NSIDC NRTSI daily numbers (year, month, day,10^6 km^2):

2012 08 20 4.33489
2012 08 21 4.33137
2012 08 22 4.29062
2012 08 23 4.19043
2012 08 24 4.08920
2012 08 25 3.97332
2012 08 26 3.94326
2012 08 27 3.85419
Wow, practically three times the loss from 8/26 to 8/27 as from 8/25 to 8/26. The loss is accelerating! How alarming!

WUWT is one of two blogs I read to start every day here in the antipodes (sic).
From the discussion thread above and to quote “I decided to no longer use the phrase because it is so widely ‘misused’ ” sums up the issue quite neatly in terms of English usage. Unlike basic mathematical formulae languages evolve. If it didn’t then there would be a lot more f’s in the language than p’s. While there is some historical value in pointing out how a phrase may have been used, or what it meant it is currently accepted usage and meaning that defines what is says today. Asking your grandmother what “being gay” meant in her day will give a difefrent answer than asking someone a lot younger. The phrase may be ‘misused’ through a historical lens but for most the ‘new’ meaning is clear .
Respectfully,
James

Smokey says: August 28, 2012 at 11:27 am
“You can not produce one iota of scientific evidence showing that human CO2 emissions have anything to do with Arctic ice levels. Because there is no such scientific evidence.”
“Without evidence, your opinions are based entirely on true belief, not science.”
“Neither belief is based on science.”
Where is your scientific evidence that sea ice extent is natural? Show me your science please? I have asked you several times now, but why are you refusing to show it to us. Apparently we are missing something.
Why do you still keep providing the same link you also used in a previous blog that says nothing, absolutely nothing, about current sea ice conditions to be a natural phenomenon not caused by man or by the same conditions which were there 6000-7000 years ago?
Do you even know why there was less sea ice 6000-7000 years ago?

kadaka,

NSIDC does not have error bars on the time series plot shown in the “Daily Image Update” and the daily time series plot (usually labeled “Figure 2”) because we strive to keep the images concise and easy to read. Plus, the error bars would be quite small compared to the total extent values in the images….
For average relative error, or error relative to other years, the error is approximately 20,000 to 30,000 square kilometers (7,700 to 11,600 square miles), a small fraction of the total existing sea ice. For average absolute error, or the amount of ice that the sensor measures compared to actual ice on the ground, the error is approximately 50 thousand to 1 million square kilometers (19,300 to 386,100 square miles), varying over the year. During summer melt and freeze-up in the fall, the extent may be underestimated by 1 million square miles; during mid and late winter before melt starts, the error will be on the low end of the estimates. It is important to note that while the magnitude of the error varies through the year, it is consistent year-to-yea. This gives scientists high confidence in interannual trends at a given time of year.
http://nsidc.org/arcticseaicenews/faq/#error_bars
The gray area around 1979 to 2000 average line shows the two standard deviation range of the data, which serves as an estimate of the expected range of natural variability.
http://nsidc.org/arcticseaicenews/faq/#stdev
Scientists use standard deviations as a way to estimate the range of variability of data. In the context of climate data like sea ice extent, it provides a sense of the range of expected conditions.
http://nsidc.org/arcticseaicenews/faq/#standard_deviation

For the 1979 to 2000 mean, the error bars would be the relative error of 20,000 to 30,000 sq/km.
The 2 standard deviations shown is about 2 million sq/km at September minimum.

I wish this new measurement tool was around 30 years ago, so we could compare the data now to the data then using the same tool. I wonder if it would show, using this method, that the current sea ice is the lowest recorded.

The marginal zone in that one depiction is huge. Frighteningly huge.

So Meier has pretty much totally trashed MASIE. So why the heck do they even bother with it?

The latest MASIE (Aug. 27) is down to 4.5 million.

kadaka (KD Knoebel), Thank you for the reference. Using the Acronym finders on line sometimes produces amusing results thanks to the predilection of other disciplines for generating their own jargon.

Gail Combs:

What will be interesting is what all these far flung chunks of ice will do to the upcoming winter freeze. The Mean Temperature above 80°N has already fallen below 0°C.

As somebody else has mentioned, the Arctic sea is still absorbing a lot of sunlight so even though the air is below freezing in some areas, it is not everywhere in the Arctic and the sea may not be below zero, particularly at mid and lower Arctic latitudes. At 78 degrees north (mid Arctic) the sea is still seeing 19 hours of sunshine.
Every year the total area and extent of sea ice continues to reduce well into September even though “average” Arctic air temperatures may be as low as -8c to -10c.
I have no scientific basis for the following, other than past observations of ice melting in a tub of water, but it seems to me that breaking up ice and spreading it around a larger area of water will tend to increase the rate of melt? The more fragmented the ice the greater the surface area of ice that is exposed to water. Smaller ice cubes melt quicker than larger ones.
Where has the ice gone? I conjecture that it has been blown out into the open sea by the storm where a larger proportion of it than in past years has melted – but we shall see when the sea ice grows again as it will tend to start forming around existing bergs.
I would count myself as a AGW “sceptic” simply because I distrust models and prefer evidence from the real world. I am fully willing to accept that evidence when it is clear and unambiguous. To me it is abundantly clear from many sources that we are seeing a very rapid loss of sea ice consistently for all the years we have records.
Whether this is part of a natural cycle or caused by anthropogenic global warming is still open to some argument, but the longer it goes on the less likely the “natural cycle” theory – particularly if it continues even after the AMO moves into a cold phase. However this sea ice melt is fully consistent with predictions resulting from the AGW hypothesis. The “warmists” are definitely winning this one!
Deniers are definitely on defensive here. If I were one I would stop posting on this, undertake a tactical retreat and only return if the evidence starts to point in my favour again!

I would like to thank Walt Meier for his professional, timely and courteous responses on this thread.

In your March 31, 2010 post entitled “Arctic Sea Ice about to hit ‘normal’”, you put a lot of faith in the Danish, Norwegian, NORSEX, and JAXA calculations—to quote you:
The Danish Meteorological Institute shows Arctic ice extent at the highest level in their six year record. … Source: DMI Ice Extent
The Norwegians (NORSEX) show Arctic ice area above the 30 year mean. … Source: NORSEX Ice Area
And the NORSEX Ice Extent is not far behind, within 1 standard deviation, and similar to NSIDC’s presentation. Note that is hit normal last year, but later. … Source: NORSEX Ice Extent
And JAXA, using the more advanced AMSR-E sensor platform on the AQUA satellite, shows a similar uptick now intersecting the 2003 data line. … Source: IARC-JAXA
Can you comment on what those sources tell us today?
Thanks.
Chris Kennedy
Anchorage, Alaska

Richard Carlson said on August 28, 2012 at 7:29 pm:

So Meier has pretty much totally trashed MASIE. So why the heck do they even bother with it?

He didn’t trash it, just pointed out that MASIE and the NSIDC Sea Ice Index are separate things for separate purposes.
It’s like the difference between a flashlight and headlights. If you’re walking around outdoors at night, you use a flashlight to identify what’s there. If hurtling down the highway in your car and you need to know what might be ahead, you use headlights. Sure, what looked like it might be a possum in the road can turn out to be an old shopping bag, but you need to know something is there while driving, thus headlights. When casually walking around, use the flashlight and know for sure what it is.
MASIE is a fine resolution operational-type product, suitable for more-urgent tasks like keeping your boat away from sea ice. False positives aren’t an issue as you’re avoiding hitting ice. The SII is for careful thoughtful results when the speed of obtaining results is less important than the definitive accuracy of them. Headlights versus flashlights.
That said, one doesn’t need a flashlight to verify a freaking tree fell onto the road. For such a dramatic loss with such a record low, MASIE should have picked it up just fine.

Smokey says:
August 29, 2012 at 11:59 am
Phil. is clearly fixated on my comments. That’s what happens when you exist in your own bubble of belief in manmade runaway global warming.
On the points under discussion there are many, many responsible “sceptics” who don’t agree with you but don’t necessarily think that “runaway global warming” is likely.
Finally, Phil still cannot understand that if CO2 rises after temperature rises, then CO2 is an effect of temperature. Rising temperature causes rising CO2, but people living in a CO2=CAGW belief bubble cannot seem to understand that basic fact. The chart Phil posted shows conclusively that even on very long time scales, temperature leads CO2.
You don’t seem to understand the processes by which rising temperatures cause increases in CO2. You certainly seem not to understand that a 1 deg rise in temperature is NOT going to result in a 100ppm rise in CO2. To get a 100ppm CO2 rise requires a temperature increase of several degrees and several hundreds – if not thousands – of years so that CO2 can be ‘dug out’ from the deep ocean.

Is there any way mw can tell surface water from open water?

Records are fun, but it’s the trend that matters.
If I had to pick a turning point it would be when WUWT predicted 4.9 for ice extent this year. So much for Anthony’s “sea ice is recovering” theory. That was the “horse meet water” moment. I’m unsurprised he refuses to drink.
REPLY: Your statement works both ways, one of the most interesting aspects of this years storm induced breakup is that it allows for open surface water that normally would not be exposed to release LWIR into space. Lets see what happens in the refreeze. Also, look up 1922. – Anthony

Yeah, that big storm and consequent smaller ones over the same area sure did a number on the ice. A quick rebound (refreeze)in extent would not surprise me one bit in the Chukchi Sea and East Siberian Sea with the ice(albeit low concentrations) still floating around.

Phil.,
The fact that CO2 allegedly haven’t been this high in 500,000 years is immaterial to the debate. The debate revolves around whether CO2 causes CAGWism, and there’s no evidence it does. The earth has been Co2 starved for the past 500,000 years. More CO2 is generally better for life. See co2science.org.

Greg Beasley, I gather that data is now pay-walled. The Defence Department that funded it thinks it can persuade us to pay for it…

The best part is when you discount the satellite record as being too short a time period (only 33 years.. though for UAH, or RSS sat temps that’s OK)… and in the same post wax on about how MASIE and IMS, which have been up for last than 10 years… shows different numbers.
Funny.
Meanwhile, NSIDC is not the only place to go for long-term ice data… they’re simply the latest to show a record because of how they average out the days. Others have seen this coming for over a week.
http://neven1.typepad.com/blog/records/
9 records have been broken so far this year (in order of record broken):
Uni Bremen
Arctic ROOS Area
Cryosphere Today
Danish Met Inst.
Arctic Basin area (also put out by Cryosphere Today)
IJIS (Japan)
Arctic ROOS Extent
NSIDC
and today
PIOMAS – Volume
…….
http://neven1.typepad.com/.a/6a0133f03a1e37970b0177446fc134970d-pi
…….
Face it fellows, the Arctic is a shadow, quite literally, of it’s former self.
When it walks like a duck, talks like a duck, flies like a duck, quacks like a duck, waddlies like a duck, swims like a duck, dives like a duck, fishes like a duck, and paddles like a duck. It’s a duck!

A few years back Steve Goddard at The Register learned about the dangers of trying to interpret NSIDC charts without a full understanding of them. The Editor at The Register, and Steve Goddard, added retractions to that web page, stating that NSIDC got it wrong and that Goddard’s alternate interpretation was off the mark.
http://scienceblogs.com/islandofdoubt/2008/08/26/how-to-admit-youre-wrong/
In any case, why wast a lot of time on charts when you can see the melt down for yourself?
Watch this from space, there is more open water to come this year:
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?project=aeronet&subset=Resolute_Bay.2012241.terra.2km

From Phil. on August 31, 2012 at 3:42 pm:

Unfortunately it’s Smokey who doesn’t understand it!
“CO2 levels up to twenty times higher caused no global harm” he says, of course that was when there was no life on land. Considering that the rain would have the pH of vinegar not too surprising. Only 15% O2 in the atmosphere not too healthy either!

Water normally combines with carbon dioxide from the air to form a weak carbonic acid solution. Atmospheric CO₂ concentrations of 350ppm would yield a 5.6pH solution from distilled water left exposed to air.
At 25 times a 400ppm concentration, the pH would be 4.9.
Common distilled vinegar, aka white vinegar, runs about 2.4pH. With the logarithimic nature of the pH scale, that’s around 320 times the acidity from a CO₂ atmospheric concentration more that 25 times current.

Once land plants developed the CO2 levels dropped to near contemporary values, we had the development of land animals, coincidence? (Late Devonian extinction)

Comparing the graph from Smokey with the timeline of life on Earth, land animals were present with CO₂ levels about five times contemporary values, far in excess of the IPCC’s absolute worst case scenario by 2100. Indeed, after lowering to current levels for between around 330 to 270 million years ago, CO₂ levels then significantly rose, only lowering to “worst case” about 50 million years ago, and to about current levels around 35 million years ago when grasses evolved and grasslands expanded.
Yet despite the CO₂ levels being so far in excess of current amounts, even in excess of “worst case” from around 260 to 50 million years ago, life went on. Go figure.
Thank you for providing this display of your scientific knowledge, it was quite enlightening.

“A new record minimum of the Arctic sea ice extent”
http://www.eorc.jaxa.jp/en/imgdata/topics/2012/tp120825.html
Happened on Aug. 24, four weeks earlier than 2007’s minimum, and it happened despite a very slow starting melt season. And it’s still dropping, with at least 2 or 3 weeks left in the melt season.

oops, ims close to a new record!!!
http://www.natice.noaa.gov/ims/images/sea_ice_only.jpg

MASIE is down to 4.0 mil sq/km, a bit higher than other indices, but this value is lower than previous records for NSIDC, IJIS and Arctic ROOS extents. So I think that’s MASIE down for the record books.
http://nsidc.org/data/masie/
IMS looks like its inevitable to break the record soon. I wonder how WUWT will comment. I guess it will suddenly be remembered that weather isn’t climate. But will the full 33 year trend rate a mention? Or the longer-term data sets and the trends they reveal?
No, if we start looking back in time I guess we’ll forget again that weather isn’t climate and pull out a few years in the 30s.
Once you know the steps, the dance isn’t that hard.

And to boot, the accelerated loss has happened since global warming has stopped:

Let’s see, warming from 1998 to present is 0.53C/decade for Arctic ocean sea surface temps. And that’s also the trend for the whole satellite period.
http://vortex.nsstc.uah.edu/public/msu/t2lt/uahncdc.lt
Perhaps some of the warming expected from increased GHGs has gone into melting the NH sea ice (and global glaciers), as well as into the deeper oceans as postulated. Surface temps are a one-dimensional view of where the heat may go in the system.
But NH sea ice is probably not in equilibrium with the warmer temps there, so even if temperatures stopped going up in the Arctic, summertime retreat would probably keep going for a few years. There’s little doubt now that the pack has been markedly thinning over the years.

Jean Meeus says:
August 27, 2012 at 11:10 pm
“Today though, looking at the NSIDC extent graph, he [Mann] seems happy, declaring it ‘official’.”
I never understand the warmists. On the one side they say they are alarmed by the “catastrophic” global warming, but at the other side they are happy that the polar ice is melting.”
————————————————————————————————————–
I don’t understand that, either. Several sites I’ve been to, warmists are gloating about this years melt. Happy as all get out about the new low, despite their “concern” about the shrinking ice cap. The only thing that would probably make them happier is if hundreds or thousands of dead polar bears were now appearing.

Most recent three values for the MASIE daily index in square kilometers
4,027,497.41
3,935,061.38
3,863,517.58
ftp://sidads.colorado.edu/DATASETS/NOAA/G02186/masie_extent_sqkm.csv

Checked Realclimate. They posted an article about this but no mention whatsoever of the Super Cyclone breaking up the ice which contributed to the loss. No mention whatsoever of the Super Cyclone in the first 75 comments, either. They’re acting like the cyclone never happened.

They don’t mention attribution at all, just give figures. They do link to the NSIDC announcement I linked above, which mentions the cyclone.
When news of the cyclone first arrived at WUWT, brought by visitors from Neven’s blog, it was downplayed as just another storm, with a frequency in summertimes of 1 in 4 years, as a couple of posters put it. Now that records have been broken, the storm is cast here as a ‘supercyclone’. Suddenly the storm is no longer ordinary.
But if storms like this do come once every four years, then why haven’t we seen retreat nearly as extensive as this summer’s over the last several decades?
Because there has been a long-term decline in sea ice, pre-conditioning the pack for such events. Summer weather conditions in 2007 were even more favourable to sea ice retreat than this year’s, and that year, to saw a record-breaking minimum – a combination of the long-term trend and weather patterns for that year.
It aint the storm, it aint the weather, and it aint even the long-term trend that makes a record-breaker. It’s a combination of trend and weather. And it’s just a number. What really matters is the trend. And the metric that really matters for analysing sea ice change in the Arctic is not extent or area, it’s volume. Area and extent changes, even year on year, are indicators.

REPLY: Sorry, but it IS the weather, Every year near maximum ice melt time, weather is in fact the biggest factor on Arctic sea ice. Always has been, always will be. This year weather in the form of a storm had an even bigger impact than usual. Get over it. – Anthony