NSIDC: satellite sea ice sensor has “catastrophic failure” – data faulty for the last 45 or more days

http://gbailey.staff.shef.ac.uk/researchoverview_images/dmsp.jpg
The DMSP satellite is still operating, but the  SSM/I sensor is not

Regular readers will recall that on Feb 16th I blogged about this graph of arctic sea ice posted on the National Snow and Ice Data Center sea ice news page. The downward jump in the blue line was abrupt and puzzling.

nsidc_extent_timeseries_021509

Click for larger image

Today NSIDC announced they had discovered the reason why. The sensor on the  Defense Meteorological Satellite Program (DMSP) satellite they use had degraded and now apparently failed to the point of being unusable. Compounding the bad news they discovered it had been in slow decline for almost two months, which caused a bias in the arctic sea ice data that underestimated the total sea ice by 500,000 square kilometers. This will likely affect the January NSIDC sea ice totals.

Map of sea ice from space, showing sea ice, continents, ocean
Figure 1. High-resolution image Daily Arctic sea ice extent map for February 15, 2009, showed areas of open water which should have appeared as sea ice. Sea Ice Index data. About the data. Please note that our daily sea ice images, derived from microwave measurements, may show spurious pixels in areas where sea ice may not be present. These artifacts are generally caused by coastline effects, or less commonly by severe weather. Scientists use masks to minimize the number of “noise” pixels, based on long-term extent patterns. Noise is largely eliminated in the process of generating monthly averages, our standard measurement for analyzing interannual trends. Data derived from Sea Ice Index data set.

—Credit: National Snow and Ice Data Center
Graph with months on x axis and extent on y axis
Figure 2.
High-resolution image
Daily total Arctic sea ice extent between 1 December 2008 and 12 February 2009 for Special Sensor Microwave/Imager SSM/I compared to the similar NASA Earth Observing System Advanced Microwave Scanning Radiometer (EOS AMSR-E) sensor. —Credit: National Snow and Ice Data Center

Dr. Walt Meier of NSIDC had planned to do a guest post here on WUWT, but this evening, with the magnitude of the problem looming, he’s asked to defer that post until later. I certainly can’t fault him for that. He’s got his hands full. Hopefully they have a contingency plan in place for loss of the sensor/space platform. I applaud NSIDC for recognizing the problem and posting a complete and detailed summary today. I’ve resposted it below in its entirety. Note that this won’t affect other ice monitoring programs that use the  Advanced Microwave Scanning Radiometer (EOS AMSR-E) sensor, which is on an entirely different platform, the AQUA satellite.

UPDATE: 2/19 Walt Meier writes with a clarification: “One detail, though perhaps an important [one]. I realize that it is bit confusing, but it is just one channel of the sensor that has issues. And it isn’t so much that it “failed”, but that  quality degraded to the point the sea ice algorithm – the process to convert the raw data into sea ice concentration/extent – failed on Monday.” – Anthony

From NSIDC Sea Ice News:

As some of our readers have already noticed, there was a significant problem with the daily sea ice data images on February 16. The problem arose from a malfunction of the satellite sensor we use for our daily sea ice products. Upon further investigation, we discovered that starting around early January, an error known as sensor drift caused a slowly growing underestimation of Arctic sea ice extent. The underestimation reached approximately 500,000 square kilometers (193,000 square miles) by mid-February. Sensor drift, although infrequent, does occasionally occur and it is one of the things that we account for during quality control measures prior to archiving the data. See below for more details.

We have removed the most recent data and are investigating alternative data sources that will provide correct results. It is not clear when we will have data back online, but we are working to resolve the issue as quickly as possible.

Where does NSIDC get its data?

NSIDC gets sea ice information by applying algorithms to data from a series of Special Sensor Microwave/Imager (SSM/I) sensors on Defense Meteorological Satellite Program (DMSP) satellites. These satellites are operated by the U.S. Department of Defense. Their primary mission is support of U.S. military operations; the data weren’t originally intended for general science use.

The daily updates in Arctic Sea Ice News & Analysis rely on rapid acquisition and processing of the SSM/I data. Because the acquisition and processing are done in near-real time, we publish the daily data essentially as is. The data are then archived and later subjected to very strict quality control. We perform quality control measures in coordination with scientists at the NASA Goddard Space Flight Center, which can take up to a year. High-quality archives from SSM/I, combined with data from the earlier Scanning Multi-channel Microwave Radiometer (SMMR) data stream (1979–1987) provide a consistent record of sea ice conditions now spanning 30 years.

Data error sources
As discussed above, near-real-time products do not undergo the same level of quality control as the final archived products, which are used in scientific research published in peer-reviewed journals. However, the SSM/I sensors have proven themselves to be generally quite stable. Thus, it is reasonable to use the near-real-time products for displaying evolving ice conditions, with the caveat that errors may nevertheless occur. Sometimes errors are dramatic and obvious. Other errors, such as the recent sensor drift, may be subtler and not immediately apparent.  We caution users of the near-real-time products that any conclusions from such data must be preliminary. We believe that the potential problems are outweighed by the scientific value of providing timely assessments of current Arctic sea ice conditions, as long as they are presented with appropriate caveats, which we try to do.

For several years, we used the SSM/I sensor on the DMSP F13 satellite. Last year, F13 started showing large amounts of missing data. The sensor was almost 13 years old, and no longer provided complete daily data to allow us to track total daily sea ice extent. As a result, we switched to the DMSP F15 sensor for our near-real-time analysis. For more information on the switch, see  “Note on satellite update and intercalibration,” in our June 3, 2008 post.

On February 16, 2009, as emails came in from puzzled  readers, it became clear that there was a significant problem—sea-ice-covered regions were showing up as open ocean. The problem stemmed from a failure of the sea ice algorithm caused by degradation of one of the DMSP F15 sensor channels. Upon further investigation, we found that data quality had begun to degrade over the month preceding the catastrophic failure. As a result, our processes underestimated total sea ice extent for the affected period. Based on comparisons with sea ice extent derived from the NASA Earth Observing System Advanced Microwave Scanning Radiometer (EOS AMSR-E) sensor, this underestimation grew from a negligible amount in early January to about 500,000 square kilometers (193,000 square miles) by mid-February (Figure 2). While dramatic, the underestimated values were not outside of expected variability until Monday, February 16. Although we believe that data prior to early January are reliable, we will conduct a full quality check in the coming days.

Sensor drift is a perfect but unfortunate example of the problems encountered in near-real-time analysis. We stress, however, that this error in no way changes the scientific conclusions about the long-term decline of Arctic sea ice, which is based on the the consistent, quality-controlled data archive discussed above.

We are actively investigating how to address the problem. Since we are not receiving good DMSP SSM/I data at the present time, we have temporarily discontinued daily updates. We will restart the data stream as soon as possible.

Some people might ask why we don’t simply switch to the EOS AMSR-E sensor. AMSR-E is a newer and more accurate passive microwave sensor. However, we do not use AMSR-E data in our analysis because it is not consistent with our historical data. Thus, while AMSR-E gives us greater accuracy and more confidence on current sea ice conditions, it actually provides less accuracy on the long-term changes over the past thirty years. There is a balance between being as accurate as possible at any given moment and being as consistent as possible through long time periods. Our main scientific focus is on the long-term changes in Arctic sea ice. With that in mind, we have chosen to continue using the SSM/I sensor, which provides the longest record of Arctic sea ice extent.

For more information on the NSIDC sea ice data, see the following resources on the NSIDC Web site:

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241 thoughts on “NSIDC: satellite sea ice sensor has “catastrophic failure” – data faulty for the last 45 or more days

  1. A note to commenters here. On the previous thread on this issue, a few posted commentary that was boorish to say the least. So here are the ground rules for this post: no discussions of “tabloid”, “conspiracy”, or bashing of Dr. Meier.

    Posts that have such commentary will be wholesale deleted. – Anthony

  2. Will NSIDC issue a correction to the media?

    “Arctic sea ice coverage was at its sixth lowest January extent since satellite records began in 1979, according to the National Snow and Ice Data Center. Average ice extent during January was 5.43 million square miles.”

    This was released in a number of news outlets –

    http://www.examiner.com/x-219-Denver-Weather-Examiner~y2009m2d18-January-was-seventh-warmest-for-globe

    And was also part of the larger NOAA January report –

    http://www.noaanews.noaa.gov/stories2009/20090218_globalstats.html

  3. Its sad to see F13 degrade. Having personally helped build the SSM/I sensors its a bit like having family get sick. We can take solace in the fact that the original mission life was just 3 years and it worked for over 4 times its design life. Hopefully there are still other sensors available to replace the missing data.

  4. Bravo Anthony! Your original statement “Something odd is going on . .” has suddenly become “Houston, we have a problem.”

  5. It’s not that I like to repeat myself but I did question the december flatness (and slight drop) several times already. In view of this important piece of information, will they review, as a minimum, the past 6 months data?

    REPLY: I’m sure they’ll go over everything, because much of the data is now in question. – Anthony

  6. I noticed that some Canadian cities have disappeared off the national temperature map on the right. As an Australian, I had always thought that there were friendly relations between the US and Canada.

    REPLY: If the data isn’t reported from the station, the plot is not made- Anthony

  7. To say that Dr. Meier has his hands full is an understatement. I still wonder why it took so long for anyone to question the gradual appearance of oddities in the visual representation of ice extent until this late date, e.g. the growing number of gray areas.

    What I am wondering about now, from that last paragraph in today’s explanation, is why, if AMSR-E data is so much more accurate, it can’t be used. Why can’t the newer data from AMSR-E be spliced onto the previous data? I hope that in a future post he can go into more detail about this.

    I do notice that their representation of current AMSR-E data shows ice extent near 15 million km². I assume that JAXA also uses this data; however, their latest early number for 18 Feb puts ice extent at 14.185 million km², so I guess they’re filtering the data with their own algorithm.

  8. So although they have consistent data far 30 years, they are now recognising that the data provide “less accuracy”. The question is how accurate are that 30 years of data. Can the statement “the scientific conclusions about the long-term decline of Arctic sea ice” be relied on, since they are based on less accurate data?

  9. Anthony,

    Thank you for this revelation.

    In mid December, I noticed that sea ice growth had flatlined and thought that strange since it had been very cold in N Canada and N Russia. I wrote to NSIDC on December 21 and received the reply below from David Korn at NSIDC. I still am not sure why the sea ice would not have grown when there was no sunlight and it was darned cold. That is obviously highly subjective on my part … but still.

    If the mid December levels are indeed accurate (they may well be) then growth rates have little to do with air temperatures but can only be wind and or ocean currents.

    The scientist was careful NOT to blame “climate” and said it was a short-term “weather” occurrence.

    I remain highly skeptical about sea ice measurements. Your revelation is most interesting. Makes one wonder a lot.

    Clive Schaupmeyer
    Alberta

    REPLY FROM NSIDC Dec 22, 2008.

    Thank you for contacting NSIDC. I forwarded your question to one of our
    sea ice experts and here is his response:

    “NSIDC scientists are quite certain that the almost complete lack of increase in ice extent since about December 10 is real. Satellite-derived ice extent from the SSM/I (Special Sensor Microwaver/Imager) used to create the time series on our website was checked against extent based on the AMSR (Advanced Microwave Sounding Radiometer) instrument. AMSR shows the same pattern. This gives us independent confirmation. Past 10 days has seen a very unusual atmospheric pattern. It has been very warm over the Arctic Ocean, and wind patterns have favored a compact ice cover. While the lack of increase in ice extent is certainly quite unusual, we would not read too much into it right now at it appears to be weather related versus climate related. It will be interesting to see what happens over the next week.”

  10. It is good to see an error acknowledged and steps taken to correct it.

    John Egan’s comment is important and I hope that the correction is issued when available. My own sense is that the sea ice people are not “on the team” but rather trying to bring real data to the discussion. That’s vital and so is error correction.

    We need good data and, thankfully, when errors occur there is at least one group of scientists who are willing to deal with the errors.

  11. This is why I WOULD believe data from NSIDC in the future, whereas before I had my doubts. This is a most enlightening phenomenom. So does the extra 500,000 put the line back up “normal” maybe someone can re-do the graph to what it should/would look like corrected. BTW if it does really melt again I would trust NSIDC to truly report the results and corrections ect..

  12. Re Previous it is however a bit of a worry that cryosphere today puts this on top of their web page (see below in parenthesis) It shows a bias towards any mention that ice may be close to normal especially in light of recent NSIDC problems. This is one site which I would have trouble with just becaue of this. They should just put the data up and not put comments like this. It actually does a disservice to their “global warming” cause.. but on the light side, being a skeptic I applaud it! LOL

    “February 15, 2009
    In an opinion piece by George Will published on February 15, 2009 in the Washington Post, George Will states “According to the University of Illinois’ Arctic Climate Research Center, global sea ice levels now equal those of 1979.”

    We do not know where George Will is getting his information, but our data shows that on February 15, 1979, global sea ice area was 16.79 million sq. km and on February 15, 2009, global sea ice area was 15.45 million sq. km. Therefore, global sea ice levels are 1.34 million sq. km less in February 2009 than in February 1979. This decrease in sea ice area is roughly equal to the area of Texas, California, and Oklahoma combined.

    It is disturbing that the Washington Post would publish such information without first checking the facts.

  13. RE: My post above and the reply from NSIDC

    The reply said, “It has been very warm over the Arctic Ocean”

    I know oceans are way different than land, but the mean temp for December at Alert was -37°C and the December mean was -42°C at Eureka. I checked one inland base in Siberia (Dzalinda) and the temps around mid December were -40 and -50°C. Land is not ocean. Fine. But golly why would it be “very warm over the Arctic Ocean” in that same period when the surrounding arctic lands were bloody cold? I don’t get it.

    Maybe “very warm” is -30°C ☺ I am most skeptical about sea ice data.

    Thanks Anthony. Good stuff. Best wishes,

    Clive Schaupmeyer
    Alberta

  14. well, it took two days but they have come clean.
    really this is no problem but with the hipe of co2 etc. it becomes a big deal,
    I am glad not to be in there shoes as to get things back on line.

  15. VG (23:03:42) :

    “This is why I WOULD believe data from NSIDC in the future, whereas before I had my doubts.”

    In the future, just as in the past, errors in data processing and hardware systems will inevitably occur. Which reminds that no measurement technology is infallible, nor should it be considered unreliable. For greater accuracy, considering the weight given to sea ice by MSM and policy makers, field measurements could be of great value. As noted in recent sea level measurements, in-situ data sets often conflict with satellite measurements. And in the past, NOAA satellites have had significant calibration problems yielding entire records unusable.

    Again, thanks to the NSIDC staff for addressing this issue openly. And to their volunteers who, apparently are charged with maintaining the website but are not compensated for their time.

  16. Congrats to Sven in the last thread about this, in spotting the trend was higher than normal compared to 2 other graphs since the start of the year.

    I personally only look at the JAXA graph but it pays to look at multiple I guess to be able to pick up on anomalies of this sort.

    I wonder if Anthony’s original blog entry and comments later made them look more closely to help them spot the failing sensor problem more quickly or whether it was already being investigated? If the former then I retract my statement that this was not worth commenting on, it certainly was!

    Regards

    Andy

  17. Dr Meier, if you’re watching, I’d like to add no personal criticism at all. How could I? You have done nothing wrong.

    But I would like to make a point: in the world of the Internet and especially in the field of climate science, an anomaly in a reading from a satellite is news and it is worth investigating even if the anomaly turns out to be nothing.

    In this case, it pointed to something rather severe.

    I don’t ask for an apology (nor I think, would Anthony). But I would like an acknowledgement that Anthony was correct to bring this to everybody’s attention. It is in no-one’s interest to have bad or doubtful data in the record, I’ll think you’ll agree.

  18. Argh, that’s a blow for me – I just loved to check their plots from time to time to see how ol’ good arctic was doing…

    I guess we “only” have JAXA, ROOS and cryosphere now. It’s always better to have multiple sources to guess trends…

    Concerning the CT post, I totally agree with them of course. They should not tolerate that a journalist uses fake numbers and cites them as a source, whatever the bias. It’s a question of reputation.

  19. I also want to add my voice in thanking Dr. Meier for the oneness of this discourse.

    Errors have happened, will happen again. It is the sign of a true scientific discipline that errors are acknowledged openly, and corrected. Let us hope that other data providers are as open as this.

    It is not surprising that the error was not caught before it became large. When most of the publicly funded climatologists and technicians on all levels are biased towards AGW then human error in not questioning acceptable to their theory data can enter as a bias in not checking thoroughly. Let us hope this will be a warning bell for all people dealing with data.

  20. So was there really a noticeable pause in ice growth from December 12 to 19 caused by an anomalous atmospheric pressure pattern, or was that an early indicator of the sensor malfunction ?

  21. let’s hope the other satellite(s?) will continue to work this summer,
    helping to prevent cruiseships from being stuck,
    or prevent others from stupid ideas like kayaking through the recovering ice.

  22. Anthony. I do not wish to belabour the point about the missing Canadian cities on the National weather map, but I look at the map everyday to get an idea how patterns of warm and cold move around over the American continent. I cannot recall ever seeing the Canadian stations missing. That is why I mentioned it. I did not think that Canada or the US had seceded from each other!

  23. Dr Meier, I look forward to your posting here. I’m glad that we seem to be gradually cracking the issues that have led to so much irresponsible reporting on scary non-existent Arctic melt scenarios – at least, with regard to data integrity. I hope to see issues of media science reporting integrity, following on the heels of this.

    Everyone, if you want some basic understanding of the Polar regions and the questionable Steig Antarctica paper and its 10-year genesis, enjoy Warming Antarctica by Paintwork and the rest of the page. We are all still learning.

  24. Clive (23:21:02) :

    Since water has vastly greater thermal capacity than air the air temperature can safely be reckoned to depend on water temperature over any reasonable expanse of ocean (as we know well in the UK). Therefore although land air temperatures are indeed cold enough to freeze brass monkeys, let alone water, I’d guess that the arctic ocean could be “warm” due to currents, etc. and thus lead to less sea ice forming.

    Good work all round on this story.

  25. On February 16, 2009, as emails came in from puzzled readers, it became clear that there was a significant problem

    Kudos to ICECAP and WUWT. Citizen scientist bloggers discovered and reported the erroneous readings. That is pretty cool. Thanks to the Internet, science is becoming a more public undertaking, a less esoteric and hidden away in laboratories process. That’s the trend, anyway, and it’s a very healthy one, IMHO.

    Thank you, Anthony, for being a leader in this new wave, this new gestalt of science.

  26. In the description of the sensor systems, they are described
    as passive. I wonder why they don’t use a Multi Frequency
    Synthetic Aperture Radar? SAR systems are very good at
    seeing density differences regardless of weather, and with
    the addition of CCD (coherent change detection) processing
    they could yield some incredible animations. With Interferometric
    Synthetic Aperture Radar and CCD processing you could watch
    the ice grow and retard in 3D.

    Sorry, this is a link to Wikipedia, but you’ll get the Idea!

    http://en.wikipedia.org/wiki/Interferometric_synthetic_aperture_radar

  27. From NSIDC “We stress, however, that this error in no way changes the scientific conclusions about the long-term decline of Arctic sea ice, which is based on the the consistent, quality-controlled data archive discussed above.”

    For sure, when the error is this way… doesn’t change anything for them.

  28. Do step changes in the past data suggest a change in Artic weather, as originally thought, or does it now indicate problems with the satellite intrumentation?

    I know from exerience that equipment that suffers a catastrophic failure usually have a history of periodic problems leading up to that failure.

    It may also be worth checking the algorithms to see how they handle problematic sensors.

  29. There is lesson here for all of us. Whenever doing a calculation if the answers are what one expects one tends to accepts them without checking; if they are not what you expect you check them. In this case NSIDC were expecting lower areas of Arctic sea ice and accepted the values for a long time. If the error had gone the other way, and showed higher areas of sea ice, we can be sure they would have been checked much sooner.

  30. I would like to thank NSIDC and Dr Walt Meier for his candid explanation. Kudos.

    I shall be watching the mainstream media with interest to look for erroneous reports of massive ice shrinkage beyond summer norms from now on with a better and more informed perspective.

  31. Would there be any reason to suspect that increase in cosmic rays is going to lead to increased sensor erratica and/or failure?
    i.e. – should we expect spaceborne sensors to show increased rates of failure?

  32. “However, we do not use AMSR-E data in our analysis because it is not consistent with our historical data. Thus, while AMSR-E gives us greater accuracy and more confidence on current sea ice conditions, it actually provides less accuracy on the long-term changes over the past thirty years. There is a balance between being as accurate as possible at any given moment and being as consistent as possible through long time periods.”

    It’s of course understandable that using as many different data sources as possible enhances QA abilities and general data reliability within this field of science – thus in Meier’s obvious interest to keep the DMSP based data collection going.

    Otherwise the statement is odd – very odd.

  33. “on February 15, 1979, global sea ice area was 16.79 million sq. km and on February 15, 2009, global sea ice area was 15.45 million sq. km. Therefore, global sea ice levels are 1.34 million sq. km less in February 2009 than in February 1979. This decrease in sea ice area is roughly equal to the area of Texas, California, and Oklahoma combined.

    It is disturbing that the Washington Post would publish such information without first checking the facts.”

    I remember that recently there was a discussion about the way coastlines have been redefined and this has led to a reduction in the area counted as sea ice. Has anyone come up with figures to compensate for changing definitions?

  34. Off topic (sorry) but I think important.

    One of the alarmists’ oft’ repeated claims is that methane can provide a positive feedback mechanism. The earth warms: methane is released from the permafrost and elsewhere: methane is a GHG: more warming occurs: more methane is released….

    The earth emits radiation in the long-wave band between 4 and 50 microns with a peak at around 12 microns. Methane absorbs radiation in a narrow band around 7 to 8 microns. Almost no radiation in this band escapes at present so extra methane would have negligible warming effect.

    Am I missing something or is this correct?

  35. Neo-

    While it may have been related to sensor malfunction, there is no question that there was a very strong and stable Southerly airstream through and to the West of the Norwegian Sea, which brought unseasonably warm air North, for a considerable period. This was caused by a stable High over North West Europe and Scandinavia, holding off a deep low in the Greenland area.

    Perhaps a combination of both?

    I am pleased that the (rather obvious in terms of effect on data) malfunctioning has been recognised, but sad that we may have lost an important data source. All good wishes to Dr. Meier and his colleagues in their endeavors to overcome this problem.

  36. I’ve noticed sea level charts have been updated:

    I was wondering if this will be commented on soon.
    Normally sea levels spike at the end of the year, and then drop at midyear. Can we expect a drop in the months ahead?

    On the side, Ipersonally I wouldn’t mind if Anthony limited the comments to 500 words or something. I wonder how many really long comments actually get read. On this thread though, readers seem to be keeping them short.

  37. I was certain that it was a mistake that they would find and kindly fix. Otherwise, the graph would be a proof of James Hansen’s tipping points, if not death trains. ;-)

    More quantitatively, the sea ice anomaly has never been decreasing for 1 month even by 30% of the amount/rate that was shown on the blue graph line. Such a tripling of the record rate of decrease would be a 5-sigma effect or so.

    The null hypothesis that it was a fluke would be ruled out according to the conventional statistical criteria of verification in science.

  38. i am wondering what other sensors are degrading. Could it be more of the same for other systems. There is also a possibility of feed back as well..

    There is a feeling that technology is stable, when it isnt as stable as it seems.

  39. I’d like to apologise for the cheap shots I took in the recent-related thread.
    But with the shenanigans we’ve seen from other circles, e.g. hockey stick, Antarctica, etc., I admit I got carried away, and the last time I shot from the hip without thinking. But no excuses.

    With the media, institutions, bloggers, etc. diligently watching climate data, I’d still like to see institutions exercise far greater care in verifying data before making it public. The NSIDC’s disappearance of 1 million sq. km of ice should have thrown up a red flag. I still think they have to be more careful. It really does get down to their integrity.

    All too often do the media run with “alarming news”, and then ignore subsequent corrections. This leads to public disinformation and bad policymaking. Personally I’m tired of paying through the nose for policy that’s based on junk data and panicked populations. For some of us, the nerves are getting a raw.

  40. I stopped looking at the NSIDC data a long time ago because I stopped trusting it…and maybe unfairly so.
    But Leon makes a good point about the statement:

    “There is a balance between being as accurate as possible at any given moment and being as consistent as possible through long time periods.”

    So someone please tell me if my distrust is unfair.
    It is openly admitted that the data is not accurate.

  41. The extent of corruption of data will turn out to be vastly greater than has thus been revealed. That’s just the way of incidents like this. First limited hangout, then later, full revelation.

    It became clear to those simply watching the weather that the trend of world temperatures had turned in late 2007, but officialdom said nothing. Later it would be revealed that they perfectly well knew that a cold turn was in process but continued to realize false warnings of global warming just as inaccurate. I find it humorous that when officialdom scares the populace with AGW these days, the appeal is always to 2007 data.

    What is the answer? The same as it has been since the Renaissance. Go to the sources. Quit listening to experts whether they are dressed in Medieval frocks or White lab coats. Examine data for yourself and make your own conclusions. If you made it thru high school physics and math, you probably will come to more accurate conclusions than listening to the politically influenced science establishment.

    I find little credence in protests that while the Arctic land mass is very cold the Arctic sea is very warm. Please.

  42. The AMSR-E chart from NSIDC shown in the post above has Arctic sea ice extent close to 15 million km2.

    Yet the Jaxa website which is also using the AMSR-E data as well is only showing a little over 14.18 million km2. An extra 700,000 to 800,000 km2 would put the sea ice extent well above normal right now.

    So there still seems to be some problem.

    http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

  43. “However, we do not use AMSR-E data in our analysis because it is not consistent with our historical data. Thus, while AMSR-E gives us greater accuracy and more confidence on current sea ice conditions, it actually provides less accuracy on the long-term changes over the past thirty years.” I think what he really means here is that the new, AMSR-E data, calls into question the accuracy of their old, SSM/I data. It would be interesting to see a graphical overlay of concurrent data to see what the problem/difference is. Why are they so reticent to embrace a new technology with,”greater accuracy and more confidence on current sea ice conditions”?

    One must always remember, just because your a paranoid don’t mean them B*$tards ain’t plotting against you.

  44. They have stated that they want to maintain consistency for the purpose of analyzing the long term trend. This was the reason given for not switching to an available more accurate sensor on a different sattelite. There is a problem with this approach in that eventually all the sensors of this type will fail. So a switch is inevtible. They may as well get on with it in order to have some data instead of a hole. Certainly new sattelites will not include an outmoded sensor array just so their data can look consistent. Somebody help me out with this concept.

  45. From the NSIDC statement: “We stress, however, that this error in no way changes the scientific conclusions about the long-term decline of Arctic sea ice,….”
    .
    By “long-term” I assume the reference is to the full satellite record which goes back about 30 years. Of course, that’s hardly long-term at all when we’re talking about climate. As I understand it, if you really look at the long-term records (e.g. over the last few centuries) then the current melting is nothing at all unusual. A previous large melting peaked around 1922 and there was a lot of media interest (e.g. the opening of the NW Passage), just as there has been in recent years.
    .
    Just as in 1922, we may be close to the peak of the melting and may see significant ice growth over the coming years. Or we may not. That’s why the whole question of climate change is so interesting….
    Chris

  46. The satellite data goes back to 1972, or 37 years.

    I don’t know why they chose to restate the old records back to 1979 only. Perhaps because the trend from 1974 to 1979 was for increasing sea ice extent and 1979 was the peak.

  47. So — does this mean that the content of Anthony’s first post on the problem really was “news” worth blogging about?

  48. “Lubos Motl (03:39:01) :
    would be ruled out according to the conventional statistical criteria”

    This only makes sense.

  49. Several Posters have mentioned Cryosphere

    I check this site regularly to watch the ice extent. Does Cryosphere use the NISDC data to formulate their graphs?? Or .. are they using a different source??

  50. Not only was the astonishing error worth blogging about, but it appears that Anthony’s (and others) blogs brought a halt to extremely bad data gathering from deteriorating equipment. The kudos go to Anthony; Dr. Meier is the one who should be grateful.

  51. Leon Brozyna (22:49:26) :

    What I am wondering about now, from that last paragraph in today’s explanation, is why, if AMSR-E data is so much more accurate, it can’t be used. Why can’t the newer data from AMSR-E be spliced onto the previous data? I hope that in a future post he can go into more detail about this.

    Probably a good analogy is the USHCN network. As older manually read max/min thermometers in tired Stephenson Screen boxes are being replaced by new electronic MMTS sensors, those provide a more accurate, less error-prone data source. Being replacements, their data stream is spliced onto the older max-min data stream and overall quality is improved, life is wonderful, and everyone won. Yay!

    Except for one thing.

    As discovered by surfacestations.org (one of the great creations in citizen science in my book), the MMTS sensors are often located closer to buildings, the plastic shield elements may crud up faster than the Stephenson Screens, and the net result is an erroneous climate warming signal.

    We may have been better off to keep the old system or at least put the MMTS sensors inside the Stephenson Screens and use a wireless link to get the data inside. Given issues with my wireless weather station, I’d insist on keeping a copy of the data on the transmitter side!

    What should be done with the AMSR-E data, and almost certainly is, is to compare its data with the older sources and investigate discrepancies. This doesn’t need to be done in realtime, but should be done so that data that might help explain issues is still around.

    I’m sure things are exciting at the NSIDC this week. :-)

    BTW, I’m strongly in favor of having realtime but questionable data available along with brief and detailed statements about potential sources of error.

  52. Bill Illis you have made a good point.

    Why is there such a large discrepency in same (?) AMSR-E data that both NSIDC and JAXA are publicly reporting?

    Further, it would appear NSIDC/AMSR-E data for February 2009 is very close to 1979-2000 average for Artic sea ice extent.

    Could it be that recent and significant downward trend in Artic sea extent from 2002 is mainly due to instrument error, and that error went undiagnosed because the scientists were expecting a downward trend to fit the AGW hypothesis.

    It would seem that instrumental accuracy and has been sacrificed for scientific consistency. That must be a first in physical science.

  53. Many years ago I knew a man that worked building roads for a country in South America. He was paid by the foot. It was a very poor country so no one had a tape measure. My friend, however, did have a length of pipe that he told the inspectors was 20′ feet long. Actually, it was only 19′ long. At the end of each day this faulty measuring device was used to determine how much money the road building company had earned.
    I wonder if they are still using that old piece of pipe down there in the interest of consistency.

  54. Wow! Inaccurate data because of faulty measuring equipment. Hey Anthony! Maybe you should investigate if that could be a problem in other areas as well. ;)

  55. VG-

    Note that Mr. Will stipulated

    ** Global ** sea ice levels

    The Arctic is but one part of the global sea ice total.

    According to some sites, the Antarctic sea ice extent is very large this year.

    I suspect that the sum of Arctic and Antarctic sea ice levels for Jan 2009, are very equivalent to the combined (global) total for 1979.

  56. It is more than a little problematic that they didn’t know the sensor was not functioning and that news stories were published on bad data. It was easy to see the data was diverging from what was typically expected, yet for over six weeks no one noticed? Was no one looking … The divergence was enough that it should have tweaked their natural curiosity. Couple that with the data blanks that were showing, the warning signs were there that something was going awry.

    I sure would hope that the news stories that were released on bad data would be corrected by noting the failure, but, will the news media give the same space and prominence to correcting the error. It seems the news stories are all written about the worst data, data that supports the AGW hoax, and other data us discarded because it may diverge from the desired result. This is what science has now become.

    I am not ragging on anyone, but isn’t science all about maintaining that razor edge of curiosity when things don’t turn out as expected, or when they do?

    Frankly, I think they may want to fix their internal organization problems at the same time. They generated their own credibility problems.

  57. Newbie here – sorry if my question brings obvious answers by the educated ones.

    Isn’t the AMSR-E historical data available somehow and can’t it be used to establish a correlation to the SSM/I data? From that point, apply the correlation factor and start using only the AMSR-E sensor… Or am I missing something?

    I also applaud the very open statements about the sensor issue but I question the “(…) we do not use AMSR-E data in our analysis because it is not consistent with our historical data” part. If its data isn’t consistent, find out where it is (after all, if both sensors were measuring the same thing, data should be correlated except for a few questionable portions). Any oddity may then be arguably blamed on sensor issues (be it drift or malfunction).

    Sensors and measuring equipment always needs to be replaced eventually, so it’s always a good idea to calibrate multiple measuring instruments together and correlate them to each other. This way you can eventually replace any defective sensor/measuring device with another, start applying the correlation factor and then only use the new sensor to keep your data accurate. I don’t understand why this cannot be done here – or at least why the excuse is to keep using defective sensors instead of more accurate (and hopfully non-faulty) ones.

  58. First, I applaud Dr. Meier for owning up to this and initiating a thorough investigation of the problem. I hope a resolution is possible in the near term.

    I read though the post at the NSIDC news page (reproduced by Anthony above), and found this passage to be most troubling:

    “Some people might ask why we don’t simply switch to the EOS AMSR-E sensor. AMSR-E is a newer and more accurate passive microwave sensor. However, we do not use AMSR-E data in our analysis because it is not consistent with our historical data. Thus, while AMSR-E gives us greater accuracy and more confidence on current sea ice conditions, it actually provides less accuracy on the long-term changes over the past thirty years. There is a balance between being as accurate as possible at any given moment and being as consistent as possible through long time periods. Our main scientific focus is on the long-term changes in Arctic sea ice. With that in mind, we have chosen to continue using the SSM/I sensor, which provides the longest record of Arctic sea ice extent.”

    I really don’t understand this. It makes NO sense to continue to use substandard instrumentation when a more reliable and accurate sensors are available. Does this mean that the absolute numbers associated with sea ice extent and area are not meaningful? I suppose it’s like having a miscalibrated thermometer which reads 75 F when it’s really 65 F. You can’t change it for a more accurate instrument because your long term trends are biased by the miscalibrated thermometer! At this point, if the SSM/I is dead, then they may have no choice…

  59. If scientists scrutinized a data anomaly as if it were a tiny mole beginning to look suspicious, this would not have happened over such a long period of time. However, I do not encourage the science community to hold onto data before publishing it raw. We are all well-trained in detecting differences and have no sponsor to please. While some of us have our pet beliefs and agendas, this is balanced out by other common folk who remain delightfully curious and questioning. So dear Dr. Meier, please do not decide to “scrub, rinse, and repeat” before you post raw data. You need us. We work for very low wages and most have medical coverage elsewhere.

  60. ok dr meier you earned a bonus point of respect with me with your forthcoming explanation of the satellite error and the reasons for using this data…i would like to hear more about the accuracy of the techniques as to 15% sea ice extent and watts up with using this cutoff and how is it determined…i also think dr meier’s explanation vindicates there was something to blog about…excellent work mr watts…

  61. Ray (22:42:36) :
    It’s not that I like to repeat myself but I did question the december flatness (and slight drop) several times already. In view of this important piece of information, will they review, as a minimum, the past 6 months data?

    And the answers still the same, the flatness was real and isn’t even unusual at this time of year. There are several independent sources for that.


    REPLY: I’m sure they’ll go over everything, because much of the data is now in question. – Anthony

    “Much of the data” isn’t in question, more hyperbole like your headline, where does the quotation about “catastrophic failure” come from? At least two organizations are continuing to use the SSM/I data without obvious difficulty so “catastrophic” is obviously an exaggeration.

    REPLY: You know Phil, you really ought to read more carefully before you jump to conclusions and make accusations. The headline is directly from NSIDC’s own article, and is in the body of text here, which is why it’s in quotation marks. For an Princeton academic you should know better. An apology is in order. – Anthony

  62. Guess that explains why the site doesn’t appear to be being updated since they ‘corrected’ the initial misreporting.

    Sad news. Maybe we can use Stimulus funds to put another Bird up. :)

    Also explains why the sea ice extent they reported appears to have mirrored 2008 so much 500K makes quite a difference in the chart.

  63. Dr. Walt Meier of NSIDC
    “Some people might ask why we don’t simply switch to the EOS AMSR-E sensor. AMSR-E is a newer and more accurate passive microwave sensor. However, we do not use AMSR-E data in our analysis because it is not consistent with our historical data. Thus, while AMSR-E gives us greater accuracy and more confidence on current sea ice conditions, it actually provides less accuracy on the long-term changes over the past thirty years.”

    His comment reminded me of the classic discussion of ‘accuracy’ versus ‘precision’.

    accuracy – The ability of a measurement to match the actual value of the quantity being measured.

    precision – The ability of a measurement to be consistently reproduced.

    I took his statement to mean that the exact value of ice extent (accuracy) was less useful than the repeatability (precision) in looking for long term trends. If you have good precision in your data, it is easier to detect trends or external influences.

    As we have seen here at WUWT in an earlier thread on Arctic ice, there is a ‘circle’ at the pole that is not covered by a given satellite. If your goal is to monitor the changes at the edges of the ice, consistently leaving the ‘circle’ out of the total probably does not affect the precision, but would affect the accuracy of the actual value of total ice. Leaving the circle out of the total DOES become important if you switch satellites, and the diameter of the ‘circle’ changes. As covered in that earlier thread, comparing satellite 1 to satellite 2 data affects the apparent trend, unless you know to correct for the size of the ‘circle’. Similarly, switching sensors would require ‘adjustments’ to previous data to allow an on-going comparison. And we all know the hazards that can arise from that slippery slope of adjusting historical data.

    As noted by others, I applaud the efforts to obtain and publish quality data, and wish Dr Meier and his colleagues all the best in resolving this problem.

  64. I don’t know if someone already asked but what about the Antarctic sea ice?

    Do they have 2 different satellites: 1 for the arctic and 1 for antarctica, or is it the same satellite and was Antarctic sea ice data also wrong the last 45 days?

  65. so does this affect ijis or not? if it does, then the ice will be looking better than all but 1 of the past 7 years and about equal to that (2003)…….

    in addition to that, if you check out the graphs on this page:

    http://arctic.atmos.uiuc.edu/cryosphere/

    and add 500,000 to them, you will have a fairly unimpressive “downtrend” over the past 30 years.

  66. in fact, that would bring the ijis data to just above 2003, or the highest it has been for this time of year since the ijis graph began….it would also give this year an excellent chance of surpassing the high ice extent reached that year….

  67. Oops, I guess this is worth blogging about!

    I can’t think of a better example of why great websites like this, and the hard work of Anthony and the WUWT crew, are desparately needed. How long would the data drift (failure) gone unnoticed? How long would it have taken the AGW crowd to start using it to push their agendas? Another hockey stick in the making -and just as accurate.

    Great job Anthony!

  68. Clive (22:54:23) :
    Anthony,

    Thank you for this revelation.

    In mid December, I noticed that sea ice growth had flatlined and thought that strange since it had been very cold in N Canada and N Russia. I wrote to NSIDC on December 21 and received the reply below from David Korn at NSIDC. I still am not sure why the sea ice would not have grown when there was no sunlight and it was darned cold. That is obviously highly subjective on my part … but still.

    If the mid December levels are indeed accurate (they may well be) then growth rates have little to do with air temperatures but can only be wind and or ocean currents.

    Obviously it has to be cold enough but beyond that the actual extent is strongly dependent of drift and wind. Once the basin itself is covered with ice the growth has to be into the oceans where influx of warmer water can stop advancement of the ice.

  69. The good doctor made another mistake… he forgot credit WUWT readers and Anthony for bringing the error to his attention.

  70. Hmm, as a former “icepik” with the Coast Guard International Ice Patrol, I wonder if it’s time to go back to the good old days of human observation by ship and plane.

    There’s a reason the the Ice Patrol still tracks icebergs by plane ratrher than relying on satellite data.

  71. As a person with more than 30 years experience in remote earth sensing I wanted to comment on some back stage things that customarily go on in the day-to-day business. Our company supports NASA, NOAA, and the Not-to-be-Named other alphabet soup organizations with both on-orbit and ground based systems used to collect, transmit, transport, and array spacecraft-derived data.

    Launching satellites is way cool so almost all of the organizational management attention is focused on launch activities, maybe 85%. Ten percent might be devoted to building the spacecraft. That leaves only a tiny bit of attention to turn towards actually operating the spacecraft and a miniscule amount of that goes to analyzing the derived data.

    Among the worker bees Rocketeers are the stars of the business. Troglodytes, like my team, sitting in the darkened control rooms and serving as payload controllers are not glamorous at all. They monitor health and safety of the spacecraft, not the quality of the data. They spend all day looking at screens of data and responding to alarm conditions and developing work arounds for failed pieces of the system. (And there are always lots of failed pieces)

    The scientists who are the recipients and actually are looking at the data are not at all part of the system and are effectively on their own. None of them got to their position by being programmatic hotshots able to deal with the intricacies of planning, budgeting, executing, overseeing and managing complex programs. They are usually not at all interested in those details and do not have the staff, expertise, time, or money to worry about ash and trash details like “is the sensor working properly?” They work in locations far from the payload controllers, don’t have access to the telemetry, and certainly don’t have a detailed understanding of how things work.

    Lastly, almost all of the software on the systems still being used today are extremely unwieldy concantenations of uncommented multiple patches made by generations of programmers many of whom aren’t even alive today.

    It ain’t always a pretty picture.

    Cheers, John

  72. Dave (07:15:02) :
    I don’t know if someone already asked but what about the Antarctic sea ice?

    Do they have 2 different satellites: 1 for the arctic and 1 for antarctica, or is it the same satellite and was Antarctic sea ice data also wrong the last 45 days?

    It’s the same satellite in a polar orbit. The antarctic isn’t affected, if you compare the SSM/I and AMSR-E maps they are virtually identical, one reason being that there’s hardly any sea ice left to ‘miss’.

    mark (07:16:15) :
    so does this affect ijis or not? if it does, then the ice will be looking better than all but 1 of the past 7 years and about equal to that (2003)…….

    No because they use AMSR-E.

    in addition to that, if you check out the graphs on this page:

    http://arctic.atmos.uiuc.edu/cryosphere/

    and add 500,000 to them, you will have a fairly unimpressive “downtrend” over the past 30 years.

    Why would you do that?

  73. I reckon it’s news after all.
    I guess this extends my list of examples from the other day about just why it’s important for funny-looking items in publications used to support AGW to be investigated in a public manner – though again, this problem is obviously not a “poster” example as NSIDC were apparently looking at the oddity already and would have likely found the cause just as fast without outside prodding. But the same certainly couldn’t be said for equally unbelievable kinks in a Mann, Schmidt, or Steig graph, even if the underlying causes were as honest a defect as this sensor failure.

  74. Accuracy vs precision…..hmm.

    If the measuring device has a linearity scale degradation, I fail to understand how it can be used to determine long term trends unless the error and uncertainty is a known value.

    RSS still has a step change in their data in 1992. It sticks out like a sore thumb, yet has not been corrected; its trend is still notably higher than UAH.

    Is there a comparison of data between the two satellites for say the last 5 years?

  75. Frank wrote:
    ” First, I applaud Dr. Meier for owning up to this and initiating a thorough investigation of the problem. I hope a resolution is possible in the near term.”

    Must be a sign of the times. I always used to think it was a responsibility to own up and to correct things. Now we are expected to congratulate people for doing that.

    That it took 45 days or more to find out something was “catastrophically” amiss to me shows there’s something organisationally wrong. The NISDC in my view is a managerial mess.

    Have they know QM system?
    Aren’t their instruments calibrated and checked?
    Have they been blinded by a previous belief?

    I don’t feel compelled to congratulate anyone for admitting this “Catastrophic failure”. If my boss found out I’ve been screwing things up for 45 days, I’d be happy to get off with a reprimand.

    Speculating – had the error been in the other direction (contrary to prevailing climate doctrine) it would have been discovered in 45 minutes, and not 45 days.

  76. Phil. (07:01:26) :

    “Much of the data” isn’t in question, more hyperbole like your headline, where does the quotation about “catastrophic failure” come from? At least two organizations are continuing to use the SSM/I data without obvious difficulty so “catastrophic” is obviously an exaggeration.”

    Phil., please see the posted message from the NSIDC “News” site (reproduced by Anthony above, for your convenience):

    “The problem stemmed from a failure of the sea ice algorithm caused by degradation of one of the DMSP F15 sensor channels. Upon further investigation, we found that data quality had begun to degrade over the month preceding the catastrophic failure.”

    Also, who are the two organizations still using the SSM/I data? Links?

  77. Karl Heuer (06:32:52) :
    VG-

    Note that Mr. Will stipulated

    ** Global ** sea ice levels

    The Arctic is but one part of the global sea ice total.

    Yes he stipulated global sea ice from CT, but as CT posted their global sea ice values which showed Will to be wrong I’m not sure what your point is?

    “our data shows that on February 15, 1979, global sea ice area was 16.79 million sq. km and on February 15, 2009, global sea ice area was 15.45 million sq. km. Therefore, global sea ice levels are 1.34 million sq. km less in February 2009 than in February 1979.”

    According to some sites, the Antarctic sea ice extent is very large this year.

    Well I’d ditch those sites then because they’re wrong!

    I suspect that the sum of Arctic and Antarctic sea ice levels for Jan 2009, are very equivalent to the combined (global) total for 1979.

    Fortunately we have the data so we don’t need your suspicions!

  78. @Frank K (06:47:36):

    “I suppose it’s like having a miscalibrated thermometer which reads 75 F when it’s really 65 F.”

    See, once you know whether the miscalibrated thermometer is consistently either +10 F above whatever “real” value you arbitrarily use as a reference or about 1.15 times this reference value (i.e. 75/65=1.15 or so), then you can reliably use that miscalibrated thermometer. I guess this ties back to the “precision” vs “accuracy” issue that another poster mentioned.

    If the AMSR-E results can be mathematically related (i.e. correlated) to the SSM/I values – which is an exercise I haven’t done – then it should be possible to match both sets of data so that the AMSR-E sensor can now be reliably used.

  79. Oh how I wish all the folks involved in “the great global warming debate” were as classy and professional as Dr. Meier.

    Let me add a defense of his choice not to use the AMSR-E data. The NSIDC is a raw data source. I’d like to be able to view the data from the two separate sources and draw my own conclusions.

    Someone should merge the two data sets and I think a good normalization procedure can be devised. However, this is a separate task and should be kept clearly separate from the two raw data sets. Otherwise, there is risk of the kind of errors Mann made (pun intended).

  80. Leon Brozyna (22:49:26) (and Pierre)

    In electronics, you always hope that when something fails, it fails “hard” and does not become intermittent or “drift”. These types of failures are much harder to spot, and diagnose.

    I believe that since there are very few platforms to measure against, it is harder to spot this kind of drift until, in this case the sensor failed “hard”. After all, could one tell if the AMSR-E was reading high, or DMSP reading low?

    The problem is compounded by the remoteness of the sensor. You can’t exactly waltz out to it and check the calibration, although I sure that the owners would like the capability to do that.

    Dr. Walt Meier and NSIDC deserve the round of applause that they are receiving from most on this site for their openness and the care that they are taking in correcting the data. After all, I’m pretty sure that their satellite is nowhere near a BBQ pit :-)

  81. [j/k]
    So, according to the satellite info, we really WILL have an ice free North Pole this summer!
    [j/k]

    Thanks for every bit of work by everybody on this, as it is fascinating to follow.

  82. “However, we do not use AMSR-E data in our analysis because it is not consistent with our historical data. Thus, while AMSR-E gives us greater accuracy and more confidence on current sea ice conditions, it actually provides less accuracy on the long-term changes over the past thirty years. There is a balance between being as accurate as possible at any given moment and being as consistent as possible through long time periods.”

    That’s scientific gibberish, imo, except that without even looking at AMSR-E data or having read “Bill Illis (04:32:26)”, it’s possible to reasonably predict that the AMSR-E data says something different from what the NSIDC prefers – and probably prefers purely on subjective grounds.

  83. How about looking at what the conditions were like in 1922?
    Monthly Weather Review, Volume 51, Issue 3 (March 1923), page 142
    DISTRIBUTION OF ICE IN ARCTIC SEAS, 1922
    You can compare the description with Sea Ice Extent in the summers of this century using maps Cryosphere Today. For locations, see here and here.
    Selected excerpts:
    “In July the whole west coast of Nova Zembla was clear, and in August Franz Josef Land was probably accessible by open sea.”
    “[In summer] Some sealers circumnavigated Spitzbergen, a feat that is not possible in most years.”
    “[...] and though the east coast of Greenland does not appear to have been clear of ice, open water touched the coast in about latitude 74° N.”
    “On the Newfoundland Banks … July was clearer than usual”

    What is listed as exceptional in 1922, is the rule(!) in this century.

  84. yeah phil….never mind, i wasn’t keeping the different sources of data clear. i got confused. it will be fun to see the NSIDC data corrected……500,000 is a lot of movement in the graphs i have grown to love!

  85. Steve in SC (05:06:45) :

    This is perfectly logical to maintain the same data record as long as possible. If you can imagine the difficulty of digitizing the data, programming the image recognition to identify ice & edges based on different levels of contrast, brightness, saturation, refraction, clouds, etc., you can’t switch sensors and hope to duplicate results of another method. Accuracy in this sense is a misnomer. You develop all of these routines to get a program that matches observations as best you can, and it’s probably reasonable to draw conclusions from the data, but proving “accuracy” would be enormously difficult since you really can’t observe the whole arctic to verify what is ice and what is not.

    So you pick a method and stick with it so the results are repeatable year to year and day to day and hopefully are adjusted for sensor anomalies. Changing sensors would be like using a camera with a green filter for 30 years then switching to an IR filter. It isn’t going to operate the same, nor will your analysis programs. If there is a switch, you need both data sets to overlap for a long time to get the ability to correlate the new data to the old data. The newer stuff is probably more “accurate” due to higher resolution (pixel wise) and higher resolution (more bits per pixel), and probably a different sensor (wavelength). No two technologies are going to match data pixel for pixel, not even close.

    These are all things that are commonly done with industrial vision systems used in automation. They work great if everything stays the same. Change the lighting, the part surface finish, color, get the camera dirty, change the angle, zoom, move it slightly, see a feature that wasn’t there before, whatever, and you have to re-train everything. Small changes like this can throw off a recognized part area or distance by a huge percentage if it is a small area or only a few pixels. It is anything but easy to set up.

    Now try that on a planet area that is dark and cold half the year, bright and dark once a day each in the summer, has clouds, different areas per pixel, different angle of incidence of the sun every day…

    The data can be saved if they can deconstruct a new sensor sensitivity curve every day since degradation started. That might allow them to take the data, apply the curve to boost the signal where it was before degradation, and end up with reasonably decent data to feed the old recognition routines… The folks at NSIDC are going to be busy for a while.

  86. othercoast (08:03:25) :

    I reckon it’s news after all.
    I guess this extends my list of examples from the other day about just why it’s important for funny-looking items in publications used to support AGW to be investigated in a public manner – though again, this problem is obviously not a “poster” example as NSIDC were apparently looking at the oddity already and would have likely found the cause just as fast without outside prodding. But the same certainly couldn’t be said for equally unbelievable kinks in a Mann, Schmidt, or Steig graph, even if the underlying causes were as honest a defect as this sensor failure.

    Again I’m reminded how misinformation takes on a life of its own. The original, incorrect story gets the above-the-fold headlines and the corrections get buried in page 17 next to the community announcements.

    Anybody remember when the New York Times ‘discovered’ the north pole was ice free and declared this a sign of impending doom from global warming? How much fanfare did that get, and how many people missed the story about how the pole itself is often ice free during the summer, even during the coldest years?

  87. Points of interest.

    1) This episode demonstrates that the “sceintific community” now includes the scrutiny conducted on the internet. Experts and novice contributors, in many fields from around the globe, are providing a level of scrutiny never seen.
    This is an enormous benefit to science.

    2) The lesser scrutiny provided by the establishment sceintific community and their institutions and publications have not served as an adequate check and balance.

    3) The soon to be corrected sea ice trend by the NSIDC will reflect other sources which show sea ice to be nearing the average of the last 30 years contradicting the projected calamity anticipated by Hansen et al.

    4) Many goverments are in the process of adopting sweeeping policies derived from the earlier projections of massive sea ice loss from human caused global warming .

    5) The media must convey the updated science and trends which contradict the projections, urgency and need for many of those costly policies.

    6) Any and all additional unfounded alarms of imminent disaster by AGWers must be responded to with the critisism they deserve.
    With perpetrators being held accountable in every forum possible.

  88. DR (08:04:40) :
    Accuracy vs precision…..hmm.

    If the measuring device has a linearity scale degradation, I fail to understand how it can be used to determine long term trends unless the error and uncertainty is a known value.

    Perhaps you should first find out how the device is used?

    RSS still has a step change in their data in 1992. It sticks out like a sore thumb, yet has not been corrected; its trend is still notably higher than UAH.

    And UAH has a annual deviation from RSS during the austral summer, probably due to their treatment of the antarctic sea ice, this leads to a lower trend than RSS, it also sticks out like a sore thumb.

    Is there a comparison of data between the two satellites for say the last 5 years?

    Yes many. Happy hunting.

  89. However, we do not use AMSR-E data in our analysis because it is not consistent with our historical data.

    I read this as simply meaning that it’s better to accumulate as long a record as possible using the same instruments. Once the data stops being collected from this source then everyone has to process multiple data sets and use various methods to adjust between them. If NSIDC changes their data source they’ll have to formally adopt one adjustment method and hope it correctly minimizes differences between the data. As their graph with data from both sources shows, they do have very similar data from AMSR-E, but someone has to rigorously prove equivalence before they should consider cutting their data set short.

    You’ll also note that they mention how old their satellite and its sensors is. They know their bird is aging, so they know they won’t have to collect this data for much longer. Without knowing the expected lifetime, I expect it is no more than a few years and certainly not as many decades. They may as well collect their data while it is flowing. They and others will in the meantime figure out how to best process all the data.

  90. Anna v,
    “I also want to add my voice in thanking Dr. Meier for the oneness of this discourse.

    “sorry that “oneness” should be “openness”. Something wrong with my dictionary click.”

    Actually, I liked the original. It is Zen-like. Oneness. As in, we are all in this together. We need accurate data to make good decisions . . .

  91. othercoast (08:03:25) :

    I reckon it’s news after all.
    I guess this extends my list of examples from the other day about just why it’s important for funny-looking items in publications used to support AGW to be investigated in a public manner

    It’s always been my contention and personal and professional experience that the real “peer review” begins after publication, when everyone and their mother can take a shot at what’s been published, using whatever faculties and experience they have to do their own “due diligence” – at least for the purpose of trying to enhance their own understanding of reality, as well as for trying to see what is best to do overall.

    Not that Anthony is anyone’s mother, but I think his work also tends to strongly verify the usefulness of this approach, which I would also classify as a Classical vs Faux Liberal m.o., one which therefore rejects taking the words of “experts” as the “given truth” then simply repeating the words as comforting or propagandistic memes. Imo, why even presume that you have something to add to the discussion if that’s all you are going to do?

  92. I hope this will answer once and for all whether or not bloggers- who now serve as the only independent voices on AGW issues- should or should not point out when things look questionable: The answer is, “Yes.”

  93. bluegrue,
    What was unusual in the 1920′s regarding the Arctic is unusual in the early years of this century, as well.
    The only difference is that AGW fear mongering has confabulated to make normal weather fluctuations be part of some great cliamte apocalypse.

  94. It still seems to me that the real point at issue is being missed here.

    The real issue is Quality Control in published data.

    Surely anyone with a brain cell looking at the data being published would have been put on notice that 1 million Sq Km of ice disappering in such a short timescale was worthy of investigation.

    Had they done an investigation (and sensibly held off publishing the data pending the said investigation) then all this could have been avoided.

    As others have said this may well have been going on for some time and questions have reasonably been asked. That appropriate analysis has apparently not been conducted should cause the NSIDC to re-evaluate its policies.

    All government agencies should look at the quality control issue much more seriously. This is not an isolated case – in fact it is wholly reflective of the very lax approach that is taken in this area and it would not be tolerated in private industry.

    If we are to try and understand the impossibly complex climate system we should at the very least ensure we have good accurate data being provided by government funded agencies.

    It is unacceptable IMHO that these bodies take Quality Control so lightly.

    See especially the post by

    John S. (07:52:23) :

    which says it all for me.

  95. Re arctic ice flatline: I recall anecdotal evidence at “SC24″ of high latitude NH clouds in December. At the time, I noted that these could impede cooling and explain the pause in growth.
    Re Dr. Steig: More transparency on his part would be a welcome improvement, but I would not automatically lump the esteemed Dr. Steig with others in this field.
    Re sensor failure: I worked in aerospace in the early days. Sensor failure is rather more subtle than some posters here realize, evincing itself only gradually, usually in the worst possible direction and, of course, at the worst possible time.
    Re Dr. Meier: An insider’s look at this subject would be most beneficial. Dr. Meier has probably had a look at the range of misunderstandings here and can give us useful insights.

  96. Phillip Bratby (22:52:12) :

    So although they have consistent data far 30 years, they are now recognising that the data provide “less accuracy”. The question is how accurate are that 30 years of data. Can the statement “the scientific conclusions about the long-term decline of Arctic sea ice” be relied on, since they are based on less accurate data?
    A good analogy would be with taking the temperature for the past 40 years with one thermometer and then using a more accurate one for the past 10 years. You cans still see the trend by looking at the 40 years of data even though the raw numbers aren’t as accurate.

    However, is there no correlation between the two measurements? If there is, why not correct the old data to match the more correct data source and then use that going forward? We have seen a lot of other measurements manipulated, supposedly to correct them, so why not in this case?

  97. “Dave (07:15:02) :

    I don’t know if someone already asked but what about the Antarctic sea ice?

    Do they have 2 different satellites: 1 for the arctic and 1 for antarctica, or is it the same satellite and was Antarctic sea ice data also wrong the last 45 days?”

    Good question, Dave. I suspect the NSIDC satellite is a polar orbiter so it could conceivably pass over the south pole.

  98. In a lab situation, if one gets a instrument that is newer, more accurate, and more precise, one would do a calibration.

    That is, run both instruments for a period. Figure out a transform that converts the data from the old instrument to the same baseline as the new instrument. Once a decent calibration has been performed, one has essentially dramatically improved the accuracy of the older instrument – and the older data. Not the precision – the old instrument will still produce data with a larger scatter. But the average of the calibrated data from the old instrument should be hitting the baseline of the new instrument.

    This allows apples-to-apples comparisons and would seem to allow combination of the two instruments for climatological purposes. This is precisely the same (Missing!) step in changes at all of the surface stations.

    Is this something where there is sufficient data to make a calibration attempt publicly available?

  99. J. Peden wrote:
    “it’s possible to reasonably predict that the AMSR-E data says something different from what the NSIDC prefers ”

    Except that the graph in Dr. Meier’s post shows that the AMSR-E sea ice extent
    was virtually the same as the SSM/I sea ice extent until sometime in January.

  100. Scrutiny.

    To me thats the key. The guys putting this data out are allowing it to be subjected to scrutiny.

    Those of us who look at it are allowed to ask questions about it and challenge the data. Those challenges and questions should not be seen as a challenge to the personalities of those that put this data out there, but a robust questioning of the systems used. Those questions should be used to make the system of producing that data more reliable, enhancing our scientific knowledge.

    This seems to have happened here. The guys putting the stuff out found it difficult to question their own results. So others raised the questions for them. Interesting how we can sometimes not question ourselves, and then when someone does it for us, we realise that we were only fooling ourselves. This isnt a criticism of anyone, I have been there myself, many times. I try not to let it happen now, but we build up our view of the truth of the world, and occasionally that gets challenged. First we defend our view of the truth, then defend it irrationally, but after some thought we have to cave in and accept the new reality. Our new world view that we make up becomes better than the previous one.

    But this can only happen if we allow what we believe to be true to be subject to scrutiny, and are willing to be criticised for it.

    This example is a case of the system working.

    Now get that sensor fixed! (Or something).

  101. I’m glad to see that Dr. Meier has had a change of heart and decided that this issue actually is worth blogging about. I’ll look forward to reading his thread. I think it will be very useful (in a positive way) to see his world through his eyes. This crew may be a bit rowdy at times, but, for me at least, it goes a long way when such individuals in positions of authority take a little time to share insights, perspectives, etc. That’s certainly in the spirit of this blog.

  102. Seems as though the blind faith placed on satellite data may be a little misplaced, as I have suspected all along (see John S. ‘s post above). What’s needed is a weather satellite survey – http://www.satellitestations.org ? Maybe these things are crashing into each other more often than we have heard about.

    Seriously, in such a harsh environment, it’s surprising that there aren’t more frequent sensor and other equipment failures. When it’s impossible to manually examine and test equipment, maintenance must be a nightmare.

    Despite the billions spent on them, the satellite data must still be independently verified by other methods, such as ground weather stations and (didn’t know about these) ice patrol boats. The importance of the surfacestations.org project cannot be overestimated. The condition and accuracy of the ground weather station network is going to have a profound effect on the future for all of us, everywhere.

  103. Why not use both sensors? Then you have a comparison between the two, and could possibly build a more accurate historical chart.

  104. Dr. Meier,

    My perception is that you are now caught between “a rock and a hard place.” Specifically, (a) you are starting to believe that published data for which you have at least some responsibility is likely to be erroneous, and (b) people on both sides of the AGW issue are clamoring for explanations. I’ve been in a similar situation. My advice (for what it’s worth) is to take a deep breath and before making further public announcements, do the best job you can to ascertain the full extent of the problem. As you investigate the problem, you must, of course, keep your employer informed of your progress. But if you try to respond to everyone with a dog in the “AGW fight”, (a) your “wasted-time” meter will go through the roof, and (b) you’ll end up having to explain prior explanations. When you’re pretty sure you have characterized (a) the hardware/software problems, if any, and (b) the effects those problems had on published data, then and only then go public with a complete explanation. I for one would welcome such an explanation. Furthermore, as Anthony Watts via his WUWT blog/E-mails/personal communications was apparently what tipped you off to a potential problem, I believe it would be appropriate to post that explanation on WUWT.

  105. Just an untrained observer here. As someone who works a great deal with financial data at my job, I can relate to the difficulties of getting timely, accurate data, no matter if it’s collected manually or through online feeds. There’s so much that can go wrong from point a to b to c and so on. Many of our clients complain that we don’t publish quarterly reports until weeks after the quarter end, but that’s how long it takes to review the data, contact the data source (Fidelity, Charles Schwab, etc), get it corrected, review it again, etc, etc. We do however, show up-to-the-minute data on our secure client website, and unfortunately data problems can and will happen.

    I wonder if, collectively, we’ve become spoiled by the internet, the information age, and the *perception* of real-time data from all types of sources available at our fingertips. Really the only way to completely avoid publishing bad data is to release retroactively, weeks or months later if necessary, only after it’s gone through intense quality control measures. But people want it now, they don’t want to wait 3-5 weeks. So you win some, you lose some. The best compromise is to publish it now, put a disclaimer with the report, and make continued efforts to correct the data weeks or months down the line, along with written explanations of any noticable problems or changes.

    I think all of us here want the same thing: the truth. This planet is the only home we’ve got, and we want, we need to know what’s going on (or watts up with) it. Thanks to Dr. Meier for posting here and keeping us updated on the issue.

  106. Pierre Gosselin (04:14:53) :

    “There is a balance between being as accurate as possible at any given moment and being as consistent as possible through long time periods.”

    So someone please tell me if my distrust is unfair.
    It is openly admitted that the data is not accurate.

    To be fair Pierre, Could be more accurate != inaccurate.

    I say well done NSIDC & Dr. Meier for the open manner in which they have conducted themselves.

    I look forward to a guest post from Dr. Meier after all this is sorted out.

    DaveE.

  107. “On the main page of http://nsidc.org/arcticseaicenews/ “no data available” is still showing. That is simply the last large format image they produced.”

    Anthony

    Compare that to the one you saved. The downward slope is changed and the line is longer. You don’t mean that you didn’t save the last image they produced a couple days ago?

    REPLY:
    Yes I did keep that image, you can see it here:

    It appears their automation is still running, producing images. As I said, that is simply the last large format image they produced. But I see your point, this image may be bookmarked. I’ll email Walt. Thanks for the spot. This is just one more reason why they should put timestamps on the images as I originally suggested. – Anthony

    REPLY#2 and it is fixed now, 30 minutes later. – Anthony

  108. John H. (08:40:24) :

    “Points of interest.”

    Excellent points. But meeting points 5) and 6) will be extraordinarily difficult unless “citizen science” on the order of this event presses for it. To that end we have excellent resources. This and other skeptic sites, manned by informed, intelligent people must continue to monitor institutional science for anomalies. And with coherent email campaigns to institutional supervisors and sponsors – build a record of scrutiny that nudges MSM to report “glitches” and “hiccups.”

    What will be telling is if MSM covers the retractions/anomalies stories at all. They may be surprised to find an enormous public appetite for the “warming may not be man-made” angle. Reversals of this sort are fascinating to readers, evoke excitement and sell advertising. However, if sales is not their goal, we can assume that the AGW agenda is. And no submission of contrary fact will cause them to waver.

  109. bluegrue (08:25:08) :
    How about looking at what the conditions were like in 1922?
    ……………

    What is listed as exceptional in 1922, is the rule(!) in this century.

    Agreed. What those who love to trot out 1922 as an exemplar of previous arctic warming always leave out is what was happening at the other end of the arctic. In September 1921 a US-Canadian party landed on Wrangel island to try and claim it, it was unreachable due to ice for two years and all but one of the party died. The Russians also tried to get to Wrangel using ice-breakers but failed, finally made it in 1924. An ice bound Wrangel island throughout the summer is certainly not commonplace this century.

    Photo dated Aug 18, 2008

  110. An investor to a company: “May I please see your latest & audited financial reports”

    The company to the investor: “No – we don’t believe in external auditing – our processes was ‘peer reviewed’ some years ago and all our staff has an appropriate academic degree – we audit ourselves now”

    The investor to the company: “Hmmm – but what about segregation of duties within the company – how do you make sure people don’t review their own work?”

    The company to the investor: “That doesn’t matter, our boss is the smartest guy on board and he settles all disputes and pick up errors as we go along.”

    The investor to the company: “See you later”.

  111. Phil. (09:31:20) :
    [snip]

    REPLY: Phil – no more posting privileges for you until you address your comment about the headline. – Anthony

    “Much of the data” isn’t in question, more hyperbole like your headline,

    That statement is correct “much of the data” is not in question.

    where does the quotation about “catastrophic failure” come from? At least two organizations are continuing to use the SSM/I data without obvious difficulty so “catastrophic” is obviously an exaggeration.

    Again as per the statement that at least two other organizations are continuing to use SSM/I without obvious difficulty the sensor has not “failed catastrophically”. Therefore your source was clearly exaggerating (that their software may have failed catastrophically is another matter). Since I asked where the quote came from I was clearly not attributing it to you.

    REPLY: You know Phil, you really ought to read more carefully before you jump to conclusions and make accusations.

    I did neither.

    The headline is directly from NSIDC’s own article, and is in the body of text here, which is why it’s in quotation marks.

    Because it’s a quote doesn’t mean it’s not an exaggeration.

    For an Princeton academic you should know better. An apology is in order. – Anthony

    As above there is nothing to apologize for, however you should apologize for releasing information given you in confidence and remove it forthwith.

    So the comment’s been addressed and you can restore the posts now.

    REPLY: Phil your arrogance is astounding. I’ll add that because of the source, you have no expectations of privacy. Perhaps you should find another venue. – Anthony

  112. Richard deSousa (09:36:10)

    Good question, Dave. I suspect the NSIDC satellite is a polar orbiter so it could conceivably pass over the south pole.

    I tend to think that any satellite that passes over one pole would have to pass over the other.

  113. The reason to continue to use the less accurate data is the same reason we count sunspots using the old methods and not from satellite observations — that’s the consistency.

    If we counted every sunspeck and fleck and tried to somehow correlate that to the 1800s’ data the comparisons between now and then would be meaningless, always subject to the additional error margin of the correlation. The same is true for the ice extent.

  114. HOW DO THEY CALIBRATE THAT THING, ANYWAY?

    negative = 50K sq km of the Sahara?
    positive = 50K sq km of Teddy Kennedy’s cocktail ice for a night?

    But, seriously, how do they know that their measurements correspond to reality? And how often do they run calibration tests to ensure it’s functioning properly? Or do they just do perimeter measurements to find the edge? But then that wouldn’t pick up chunks floating close together.

    So, doews anyone know about that?

  115. As for Cryosphere, a quick look shows that their “old (ssmi)” data are in as bad shape as NSIDC, however their other map versions seem OK, so presumably they are based on AMSR-E data. One wonders at which point they changed over for their area data?

    Changing satellite sensors is always a difficult procedure, so it should be started as early as possible, in order to get the longest possible parallell run for calibration. Even so some of the difference between the UAH and RSS temperature records is probably due to slightly different algorithms used for a sensor change back in the early nineties.

  116. jorgekafkazar (09:22:58) :
    “Re Dr. Steig: More transparency on his part would be a welcome improvement, but I would not automatically lump the esteemed Dr. Steig with others in this field.”
    Why wouldn’t you?
    He and Gavin Schmidt routinely hand each other the mic to add moderator-replies on realclimate.org.
    Also on realclimate.org, he actively deletes any text (even quoted) by “Jeff Id”, so he doesn’t have to answer the challenges. “Jeff Id” is a guy who showed that by using data that’s less freakishly weighted towards one small sliver of Anarctica, even Steig’s type of data processing would produce far less backwards-from-reality-trending data.

    Perhaps you’re right, though – lumping him in with the others ignores how quickly he’s apparently learned the AGWer methods of quieting dissent, and that the rectal data he presents in his papaer is likely the most separated from climate reality in recent memory.

    …incidentally, that’s the same realclimate.org that makes no mention of the sensor failure. Somebody commented about it, and GS’s response was that apparently, they have enough redundancy that it won’t be a problem for further data gathering – no acknowledgement of recent erroneous data. But you knew that.

  117. Pragmatic (10:18:06) :

    Regarding my John H. (08:40:24) “Points of interest.”

    I agree the 5) and 6) will be extraordinarily difficult.

    But the cat is out of the bag with the global internet use. Our mainstream media is slipping tinot irrelevency in advance of backruptcy for many of them.
    The real time and global benefits of the internet and widepsread scrutiny it enables will only grow.

    This episode is a marvelous demonstration.

    The MSM is scrambling at great speed and panic to adapt to the
    effects of online participation by the masses.

    They realize there is an enormous public appetite for the “warming may not be man-made” angle right along with all the other real time delivered news.
    Thier problem is profit is being left out of their loop. They can’t figure out how to replace the dwindling revenue as they become less needed and relevent.
    It’s all very fascinating to readers but with near limitless sources it’s increasingly hard for the MSM to be special and worthy of advertisers support.
    Their agenda is quickly becoming noisy racket as their business model weakens and weakens and weakens.

  118. Anyone who has ever supported a long-term legacy system can appreciate Dr. Meier’s pain at facing a major data conversion. However, having acknowledged that the newer system is indeed “more accurate” than their old systems which has now failed, there is really no choice. They must do the best they can to convert the old data to match up with the new data, providing transparency on how they did it and what choices they made and why.

    It is what it is. It won’t get any easier by continuing to wait.

  119. Phil. (09:31:20) :

    REPLY: You know Phil, you really ought to read more carefully before you jump to conclusions and make accusations.

    I did neither.

    That’s a wonderfully ambiguous statement, bravo. Clearly, you ought to read more carefully, I wondered why NSIDC used the word “catastrophic,” as I’d be inclined to save it for something that involves a debris field. I concluded it must be catastrophic to their data gathering and analysis programs. May I jump to the conclusion you didn’t read it carefully?

  120. Congratulations to NSIDC for researching the error, working out the likely effect and publicising the fact that there is an error with the data – rather than simply “adjusting” it.

    It is good to know that there are some honest scientists working in the climate field!

  121. Anthony, thank you for this site. Most of the contributors discuss issues objectively, so it does not become a rant.

    In particular, thank you for the recent exchanges with NSIDC and Dr Meier. The exchanges were candid, competent, and civil. And above all, the exchanges and the publication of the data (on this site) contributed to identification of a data problem.

    Thank you.

  122. Wow, I did not know I was going to stir things up like that with Phil. Sorry guys!!! (it’s not hard to say “sorry”!)

    As you all know, there will be an expedition to measure the thickness of the ice at some point. If we are to believe the data on the ice area and if in fact it did not gow last december eventhough it was quite cold in Canada and Russia, could it be possible that the thickness of the ice would increase though? The globe is cooling down from Gore’s minuscule fever, surely the ice recovery must also be in the tickness as well as extent.

  123. gary gulrud (09:57:57) :

    > OT: Volcanism Blog and Fresh Bilge report renewed eruption of Chaiten.

    Something else made me check, what was that? Oh well.

    Useful links:

    http://eruptions.wordpress.com/

    http://volcanism.wordpress.com/ says:

    There seems little doubt that what occurred today was a major partial dome collapse, generating pyroclastic flows that penetrated a long way south along the Chaitén river valley, almost reaching the town itself. A collapse such as this is a process rather than an event, and further collapses of the structure of the dome(s), along with the release of overpressurized gases, is continuing to generate further debris flows along the length of the valley. Hence the continuing danger to the town of Chaitén referred to by ONEMI in the bulletin above.

    Well, if we can’t watch Sea Ice….

  124. Just a thought for the producers and keepers of data:
    Where news about data and its global warming ‘effects’ have been released to the press, and the data then found to be in error, why not issue a press release about the error, and strongly suggest a published correction? Good journalists may well correct the record in print.

  125. Phil needs a lot more than just a timeout, he needs a little common sense to go with a dash of humility but I expect that is not going to happen in this lifetime.

  126. Anthony,

    Good job and thank you.

    It makes me wonder how long this has been going on (signal degradation) and if it would have ever come to light if you hadn’t asked a few simple questions. Even I, as a lowly novice, saw some “unconventional” anomalies in the daily graph.

    Not implying a conspiracy, just sloppy work and complacency. It almost seems as if many Alarmists so wish that the ice will melt that their minds are conditioned to simply accept what they wish to see without question.

    Trust but Verify…………

  127. the global sea ice trend that was flat for most of the time and started a downwards trend only after 2001.
    now it has again reached it’s 1979-2000 average (adding the 500000 km^2).

    why is this important ?

    firstly, it is generally important to look at the whole picture.
    but more importantly, in the past, the AGW crowd decided only to focus on the northern hemisphere anomaly while claiming the antarctic record sea-ice was some irregular local behaviour.

    now, as some people in the AGW crowd appear to try to regard the antarctic no longer as an outlier, if may become difficult for them to ignore 1/2 of the planet.

  128. Karl Heuer (06:32:52) : wrote:

    VG-

    Note that Mr. Will stipulated

    ** Global ** sea ice levels

    The Arctic is but one part of the global sea ice total.

    According to some sites, the Antarctic sea ice extent is very large this year.

    I suspect that the sum of Arctic and Antarctic sea ice levels for Jan 2009, are very equivalent to the combined (global) total for 1979.
    —————————————————-
    The people at Cryosphere today should have known exactly where George Will’s information was coming from since, right beneath their George Will comment, they have a link to the following article (excerpted) here:

    “One important detail about the article in the Daily Tech is that the author is comparing
    the GLOBAL sea ice area from December 31, 2008 to same variable for December 31,
    1979. In the context of climate change, GLOBAL sea ice area may not be the most
    relevant indicator.”

    Any 5-year old with a computer screen and a ruler can go to Cryosphere Today and see that global sea ice areas in December 1979 and December 2008 are indistinguishable.

    Since the George Will article actually came out on February 15th, I doubt that he could have done the comparisons of that date without using a crystal ball during the drafting of the piece.

    Yet the Cryosphere Today people still disingenuously show the 1979 – 2000 mean, when they could now show the full 30 year mean as the comparator. Also, as I gather from reading above in this thread, data is available going back to 1972.

    For people with an aparent concern for the planet, they sure as heck seem to prefer less ice over more ice. The monetary dichotomy of cognitive dissonance ??

  129. Three things really stand out for me on this:

    1) Once again the quality of data in what has to be the world’s hottest debate is suspect, with an apparent lack of quality control. A key missing point, just like the “warmest October on record” seems to be the absence of a common sense review. Its like taking a steadfast view that “the numbers never lie’ without considering that the input data may not be entirely correct. This seems to be a systematic problem in the climate world.

    2) It highlights the irony of Dr Meier’s wondering whether this was something worth blogging about. This example highlights the necessity of someone to review these types of data publications (dare I say audit them?), before, as you rightly pointed out Anthony, the press or others make major issues out of completely incorrect data and conclusions.

    3) And this point, which I just don’t get: the use of SSM/I sensor compared to EOS AMSR-E sensor data. The explanation given appears to make sense on only on the first reading. What Dr Meier basically is saying is that consistency is more important than accuracy. It appears though that SSM/I sensor data is a bit dodgy, but presumably it is at least consistently dodgy! This is almost unbelievable. The simple fact is that both consistency and accuracy are important, which means that both data sources need to be tracked and compared or calibrated.
    Would this be more difficult or expensive? I don’t know and don’t care. Unless tracking the ice is unimportant, then the inconvenience and cost are irrelevant. Tracking two data sources also serves as a cross-check, which would help avert the type of embarrassing data error that has occurred.

  130. “philincalifornia (15:42:30) :
    For people with an aparent concern for the planet, they sure as heck seem to prefer less ice over more ice. The monetary dichotomy of cognitive dissonance ??”

    Maybe if they got paid a certain $ amount per km2 counted, then we’d see the sea ice grow!

  131. Please have a look at this comparison between AMSRE (JAXA site) and SSM/I (NSIDC) This compares monthly averages back to 2002. In general the AMSRE data is smaller than the NSIDC and the only significant time it is larger is in Sept 2008 when it is 170,000 sq km larger. A difference of 3.5% larger compared to AMSRE area at that time.

    There seems to be no significant drift visible in earlier data. There is an obvious difference in the algorithms used to genereate the 15% sea ice areas.

    There are many warnings on all pages that reference the real time data e.g.
    “Daily images are also available. Monthly averages are considered more accurate indicators of overall trends. Please read Image Derivation and Interpretation Resources to understand the uses and limitations of these figures”

    To see a truly amazing video of sea ice download this AVI showing the whole polar cap in motion (Very big file but worth it!)

    http://polynya.gsfc.nasa.gov/animations/amsr/amsr_seaice_north_89v_hdtv.avi

    Mike

  132. Brute (15:21:52) :

    “It makes me wonder how long this has been going on (signal degradation) and if it would have ever come to light if you hadn’t asked a few simple questions. Even I, as a lowly novice, saw some “unconventional” anomalies in the daily graph.

    Not implying a conspiracy, just sloppy work and complacency. It almost seems as if many Alarmists so wish that the ice will melt that their minds are conditioned to simply accept what they wish to see without question.

    Trust but Verify…………”

    Ain’t gunna happen. This is all just too complex and technical to verify in general, and it’s a different matter from land temps where people live, pictures can be taken of reporting stations and UHI is a comparably simple subject.
    NSIDC stated sometime early February that they had noticed a decrease in ice, and attributed it to possibly being an unusual wind pattern. At around that time ice extent had dropped around half a million square kilometers below AMSR-E.
    I don’t claim dishonesty, and if there is some occasional instance of incompetency or irresponsibility going on that’s not really an issue. To the last guy, I’m sure they honestly believe in AGW and that the Arctic is Gore’s canary in the coal mine, so when they saw a half mil loss in a matter of days in February, they apparently didn’t think about that being unusual or unlikely.
    Likely there is only a small group of scientists working year round on all the stuff that goes into processing the telemetry from this satellite, and with the possibility that “it’s the weather” like reasons for making inferences guiding some of their work, I can’t place trust in, even hard working people who hold honest convictions.

  133. Quality Control really seems to be the issue based on some earlier comments, especially from the insider. I would like to know how often these systems are checked and calibrated, and what is the estimated uncertainty in their measurements.

    From John S. (07:52:23) comments, it seems those receiving the data have little to do with the quality of the data, and those who control the hardware/software and not giving quality an high priority:

    “They monitor health and safety of the spacecraft, not the quality of the data”

    Hopefully Dr Meir could enlighten us on this, although I understand he is in a difficult position if there are issues. If we need to spend more money for better climate data I am all for that. In fact, we should be doing a lot more on the measurement side than we are, as this site has exposed many such issues.

  134. “Klimate Kip (16:25:31) :
    Meanwhile…back in the REAL world…the poor dolphins are dying from sea ice extent!”

    Ya just gotta wonder… if the sea ice numbers were right… would these precious dolphins have to die?

  135. John H. (08:40:24) :

    Points of interest.

    1) This episode demonstrates that the “sceintific community” now includes the scrutiny conducted on the internet. Experts and novice contributors, in many fields from around the globe, are providing a level of scrutiny never seen.
    This is an enormous benefit to science.

    2) The lesser scrutiny provided by the establishment sceintific community and their institutions and publications have not served as an adequate check and balance.

    3) The soon to be corrected sea ice trend by the NSIDC will reflect other sources which show sea ice to be nearing the average of the last 30 years contradicting the projected calamity anticipated by Hansen et al.

    John,

    Your post is worth repeating, so I take the liberty of reposting (part of) it. Excellent appraisal of the implications of the episode. Congrats are in order to Anthony, Dr. Meier, and all concerned, but especially to Dr. Meier for evolving from questioning the relevance of A’s “blogging” to seeing Watt’s Up as a site for developing a real dialogue about science, one that is less controlled by intellectual self-interest and tunnel vision than traditional scientific institutions tend to become….I look forward tor reading his thoughts on the problems and promises of the present situation. Crisis is almost always also opportunity, and definitely so in this instance.

    Cheers,

    -psi

  136. Re: Phil’s 24 hour timout.

    Couldn’t your policy have a catastrophic failure, and Phil be sentenced to 24 years?

  137. For an [Name of University] academic you should know better. An apology is in order. – Anthony

    Errrrm, have I missed an update of the site policy? Since when is giving away personally identifiable data part of the escalation strategy? Do I need to worry about my e-mail being given away in case I misbehave?

  138. http://www.msnbc.msn.com/id/29038734/

    FEB 5 2009:

    “It’s warm everywhere in the Arctic. It’s anomalously warm,” said Julienne Stroeve, of the National Snow & Ice Data Center (NSIDC) in Boulder, Colo.
    Both December and January have been abnormally warm months, which impacts the cyclical re-freezing of sea ice over the years, because these are “two crucial ice-growing months,” Stroeve told LiveScience.”

    “While ice is still re-freezing, ice coverage area at the end of January was still 293,000 square miles (760,000 square kilometers) less than the 1979-2000 average, according to the NSIDC. This didn’t break the record low for January ice area (set in 2006), but it put January 2009 in the top six. Including this year, January ice area is declining by about 3 percent per decade, the NSIDC reported.”

    I guess we don’t believe this, should we believe the temperature claim either?

  139. “If we need to spend more money for better climate data I am all for that. In fact, we should be doing a lot more on the measurement side than we are, as this site has exposed many such issues.”

    The only problem with giving them more money is that they’ll just hire more alarmists to spread the hysteria…

  140. Mike Bryant (16:50:36) :
    “Klimate Kip (16:25:31) :
    Meanwhile…back in the REAL world…the poor dolphins are dying from sea ice extent!”

    Ya just gotta wonder… if the sea ice numbers were right… would these precious dolphins have to die?
    —————————–
    Somewhat reminiscent of the 500+ narwhals that died last November because they didn’t have an icebreaker in the region. Although quite tragic, I do note the irony in the fact that reports at the time described polar bears coming along and eating them !!

  141. @ Rathtyen (15:58:22) :
    “What Dr Meier basically is saying is that consistency is more important than accuracy. It appears though that SSM/I sensor data is a bit dodgy, but presumably it is at least consistently dodgy!”
    “Well, we, may have, oh, missed the, uh, bullseye, and, um, in fact we didn’t even hit the, er, target, but we did get a NICE grouping.” LOL!

    @Klimate Kip (16:25:31) :
    Don’t forget the whales.

    http://gukurup.wordpress.com/2008/11/24/arctic-whales-trapped-in-ice/

  142. @pft (16:46:25) :
    “Quality Control really seems to be the issue based on some earlier comments, especially from the insider. I would like to know how often these systems are checked and calibrated, and what is the estimated uncertainty in their measurements.”

    And, as I asked above, not just how often, but HOW they are checked and calibrated, like, how do they know that the result given corresponds to what’s really there. Perhaps there’s a hint at the link provided by pkatt (13:52:53) ? …maybe here?

    http://nsidc.org/data/docs/daac/nsidc0002_ssmi_seaice.gd.html#dataaccess

    http://nsidc.org/data/docs/daac/nsidc0002_ssmi_seaice.gd.html#3.

  143. I would really appreciate it if someone could please answer these two posts.
    I am dying to know.
    Thanks;

    Robert Bateman (02:39:56) :

    Would there be any reason to suspect that increase in cosmic rays is going to lead to increased sensor erratica and/or failure?
    i.e. – should we expect spaceborne sensors to show increased rates of failure?

    mercurior (03:55:13) :

    i am wondering what other sensors are degrading. Could it be more of the same for other systems. There is also a possibility of feed back as well..

    There is a feeling that technology is stable, when it isnt as stable as it seems.

  144. While I appreciate the analysis of the Arctic sea ice data and the satellite sensor error discussed here, it must all be irrelevant. After all, I read the news and know the ice is shrinking dramatically because of CO2. The few polar bears we have left are stranded on the small bits of ice left as they melt away into the tropical waters of the Arctic.

  145. There has been and are significant problems with the F15 satellite.

    http://www.ssmi.com/ssmi/ssmi_browse.html

    “Since 2006-Aug-14 UTC, SSM/I F15 22GHz(V) channel has been degraded by a RADCAL beacon. The interference has been characterized and removed; ocean products are now available.”

    “SSM/I F15 from August 14, 2006 to the present should not be used for climate work.”

    “Beacon Alert!!!
    The F15 beacon problem has gotten much worse, beginning January 15, 2009.
    Until further notice, do not use recent SSM/I F15 for research.”

    http://nsidc.org/data/docs/daac/f15_platform.gd.html

    “Also carried on board DMSP F15 is an experimental payload, called the Radar Calibration (RADCAL) beacon, that is used to transmit C-band data for the purpose of testing C-band tracking radar performance at Vandenberg Air Force Base. RADCAL also transmits Doppler data for the Naval Research Laboratory’s Coherent Electromagnetic Tomography (CERTO) experiment.

    The RADCAL beacon operates at 150 MHz and 400 MHz. On-orbit testing conducted in August 2005 confirmed that transmissions from the RADCAL 150 Mhz beacon produced interference in the SSM/I 22 GHz vertical polarization (22V) channel and that the 400 Mhz beacon interfered with SSMT-2 channel 4 performance. The SSMT-2 on F15 has since been declared non-operational due to an unrelated component failure. Thus, users of F15 SSM/I data should be advised that the 22V channel will be dramatically degraded during RADCAL beacon transmission, particularly with regards to snow classification and depth.”

  146. Oh yes the bears.
    I just saw, again, the World Wildlife Fund (WWFusa.com commercial on MSNBC using the polar bears and AGW to pitch for donations.

    “The ice is all vanishing the ploar bears are being stranded, mother bears are leaving their cubs, they’re dying and need saving, please donate ,,,,,”

    All very sad. Not the bears, they’re fine.
    It’s the the pathetic commercial and those behind it that is sad.

    It’s such a shamelsss display of blatant lying.

  147. Extending my last post to show that the current problem is in the 22v channel,

    http://nsidc.org/data/docs/daac/nsidc0080_ssmi_nrt_tbs.gd.html

    “On 16 February 2009, NSIDC noticed significant problems with the NRT brightness temperature product. Upon investigation, the problem was found to be due to an issue with the DMSP F15 SSM/I 22 GHz frequency brightness temperature fields. The problem began around 1 January 2009 and gradually worsened until it became noticeable in the sea ice product (NRT DMSP SSM/I Daily Polar Gridded Sea Ice Concentrations). NSIDC is working to correct the issue and provide reliable NRT brightness temperature data. In the meantime, F15 data since 1 January 2009 should not be used.”

    and

    “As of 02 June 2008, NSIDC has switched its SSM/I processing stream from the DMSP-F13 satellite to the DMSP-F15 satellite. This is due to a failing recorder on F13 which has been operational since 1995 and is expected to be decommissioned in the near future. For data continuity, F15 data has been acquired back to 01 January 2008. F13 products since 01 January 2008 remain and will continue to be produced until data quality degrades to an unusable level or the satellite is out of service.

    You may continue to use data from F13 or switch to the data from F15. In switching, you should be aware of the following differences in the satellite data:

    Interference with the F15 22 GHz channel from a radar calibration (RADCAL) beacon biasing the F15 brightness temperatures 10 K to 15 K higher than F13.”

  148. Just ask the residents of the Seward Peninsula and Pt. Barrow, Alaska if they no longer have to beat the Polar Bears off with shotguns. As for the rest of the uninhabited North, who’s there to know if the Polar Bears are going extinct?
    Ask the Inuit, Eskimos and other tribes.
    When in doubt, check with the locals.

  149. So they want your money? That says volumes about the status of the Polar Bear decline. What will they do with your money? Raise Polar Bears?
    There’s a reason why affected Alaskan residents have to fight off the Polar Bears. They stalk and eat anything, including residents. They are always aggressive and have no fear of man.
    So, who wants to raise these things?

  150. Yeh, but the ER doctor guy is really cute. And if he is shameless to boot, count me a warmer. Gettin warm already.

  151. I’m wondering how long it will be before the new Washington administration finds a way to shut this and other divisive sites down in the interests of Unity.

    REPLY: I’m already working on it. I’m getting an offshore co-lo site in Tuvalu. – Anthony
    ;-)

  152. From Cryosphere Today,

    We do not know where George Will is getting his information, but our data shows that on February 15, 1979, global sea ice area was 16.79 million sq. km and on February 15, 2009, global sea ice area was 15.45 million sq. km. Therefore, global sea ice levels are 1.34 million sq. km less in February 2009 than in February 1979. This decrease in sea ice area is roughly equal to the area of Texas, California, and Oklahoma combined.

    It is disturbing that the Washington Post would publish such information without first checking the facts.

    Cryosphere Today’s own graph clearly shows the global sea ice anomaly at the end of 1979 at the same level as the start of 2009.

    And the outrageous piece of cherry picking of one date, February 15 to ‘prove’ the opposite is one of the lamest things I’ve seen in the climate debate, which is saying a lot.

    One wonders why they don’t feel shame or embarassment at such blatant distortions of the facts.

  153. MattN (11:35:29) :

    Phil., you are a piece of work….

    Second that!
    *****************************
    Looking forward to Dr. Meier’s guest post.

  154. From Cryosphere Today,
    “and on February 15, 2009, global sea ice area was 15.45 million sq. km.”

    Now that’s really something.
    What are they doing using the the “data dropouts and bad data due to satellite issues” from NSIDC?

  155. http://www.guardian.co.uk/environment/2003/dec/11/weather.climatechange

    Paul Brown in Milan guardian.co.uk, Thursday 11 December 2003 02.12 GMT Article historyThe Inuit people of Canada and Alaska are launching a human rights case against the Bush administration claiming they face extinction because of global warming.

    By repudiating the Kyoto protocol and refusing to cut US carbon dioxide emissions, which make up 25% of the world’s total, Washington is violating their human rights, the Inuit claim.

    For their campaign they are inviting the Washington-based Inter-American Commission on Human Rights to visit the Arctic circle to see the devastation being caused by global warming.

    Sheila Watt-Cloutier, the chairwoman of the Inuit Circumpolar Conference, which represents all 155,000 of her people inside the Arctic circle, said: “We want to show that we are not powerless victims. These are drastic times for our people and require drastic measures.”

    The human rights case was announced at the climate talks in Milan, Italy, where 140 countries are trying to put the finishing touches to the Kyoto protocol, the first international agreement to reduce greenhouse gases. The backing of Russia, which is hesitating about ratifying the agreement, is required to bring the protocol into force. The US is trying to persuade the Russian president, Vladimir Putin, not to sign the protocol.

    The Inuit have no voice at the conference, since they are not a nation state, but Mrs Watt-Cloutier said: “We are already bearing the brunt of climate change – without our snow and ice our way of life goes. We have lived in harmony with our surroundings for millennia, but that is being taken away from us.

    “People worry about the polar bear becoming extinct by 2070 because there will be no ice from which they can hunt seals, but the Inuit face extinction for the same reason and at the same time.

  156. http://news.nationalgeographic.com/news/2000/12/122900inuits.html

    Global Warming Melts Inuit’s Arctic Lifestyle
    Lisa Krause (July 12, 2000)
    Traditionally, the 130 members of the Inuit community of Sachs Harbor, located on the western tip of Banks Island in the Canadian Arctic, supported themselves through age-old patterns of hunting, trapping, and fishing. Recently, however, members of the community have taken on a new role: climate-change observers.

    Here, 400 miles (640 kilometers) north of the Arctic Circle, global warming is not a theory that is debated among scientists, but a reality of everyday life. Sea ice is thinning, and disappearing. Indigenous animals are moving farther north. And melting permafrost has loosened the ground enough to weaken foundations and cause homes to lean. This, plus rising sea levels, threatens to displace an entire community.

    Surrounded by signs of change, in 1998 the residents of Sachs Harbor devised a plan to document the changes affecting their home and bring attention to the very obvious signs of global warming.

    Led by Rosemarie Kupatana, a Sachs Harbor resident, Inuit Observations on Climate Change is a community-based project developed in cooperation with the International Institute for Sustainable Development. Aided by project scientists, community members are working to produce a video that will record the changes threatening their home.

    SIGNS OF CHANGE CLOSE TO HOME

    Among the most alarming changes is the disappearance of native species. Caribou, long a staple of Inuit diet, are falling through once-solid sea ice. Polar bears are moving farther north, as are seals, who need the shelter of pack ice to give birth to their young.

    As traditional Arctic species move north, new species are moving in. Grizzly bears have been spotted in territory once dominated by polar bears. Salmon, never before caught this far north, are making appearances in fishermen’s nets.

  157. How do you get sea levels to rise dramatically in the Arctic, but here they have only risen 2″ in the last century?
    Why would there be a problem with Polar Bears moving farther north when the Inuit can load up on Salmon that have moved in behind them?
    Makes me wonder how long the Inuit have been around if during some of the past warming periods they saw the Caribou fall through the ice in the past?
    (seems like a daily dinner bonus…hey honey….it’s caribou stew tonight !!)

  158. By the way,
    Once again a huge ‘thank you’ to WUWT, and all of the other skeptics who endure the ad homs, the disparaging, the slander and vilification of the AGW promotion industry for showing yet another example of how a major tenet of AGW is flat out wrong.
    thefordprefect,
    I frankly wonder if there is any truth at all in the article you posted.

  159. Mannnn… the polar bears aren’t killing us anymore and now we have lots of fish… also the caribou are still hanging around. Actually, Sachs Harbour is part of Canada. Canada can no longer care for her own? Perhaps socialism was not a good choice for Canada.

  160. Mike Borgelt (05:04:44) :

    No, a shotgun slug would do the trick very well actually – just remember to not have bird shot anywhere near your ammo bag.

  161. There are similarly shaped areas of “missing” ice in the Antarctic pictures as well. Please see:

    The “upper left” ice field has an angular section of ice “missing” and the “left” ice field has a similar hard edge on the “top” that might be “missing” ice. Perhaps WattsUpWithThat can contact Dr. Meier and ask him to take a closer look at the Antarctic data (that seems to be taking a simlarly unusual loss in ice) as well?

  162. Philip_B (22:16:55) :

    Cryosphere Today’s own graph clearly shows the global sea ice anomaly at the end of 1979 at the same level as the start of 2009.

    And the outrageous piece of cherry picking of one date, February 15 to ‘prove’ the opposite is one of the lamest things I’ve seen in the climate debate, which is saying a lot.

    One wonders why they don’t feel shame or embarassment at such blatant distortions of the facts.

    You may want to have a closer look. I did not find the data, so I took the image, enlarged it and cut and pasted together the relevant parts. One day comparisons don’t prove a difference (the alleged “cherrypick” is the date of publication), but the data confirm the conclusion. Here’s 1979 and the last few years, blue is the sea ice area. Here is the collage:

    I’d be interested to get your definition of “at the same level”, Philip_B.

  163. hunter (05:37:54) :
    thefordprefect,
    I frankly wonder if there is any truth at all in the article you posted.

    Prove to me the statements made are false. They were 2 articles from 2 sources that were not blogs.

  164. bluegrue,
    The pooint is that
    1) the data source is no longer credible
    2) if it is correct, the actual difference is not significant, and is not indicative of anything like what Hansen & co. claim- that we are near a tipping point with a catastrophic end result.

  165. JUST ASKING….

    Error Analysis

    http://nsidc.org/data/docs/daac/bootstrap/index.html

    Under ideal winter situations when only thick ice and open water are present, ice concentration can be derived with Bootstrap technique at an accuracy of about five to 10 percent, based on standard deviations of emissivities as used in the formulation. Errors are higher in the seasonal ice region than in the central Arctic region because of higher standard deviations of consolidated ice in the 19 vs 37 GHz plots.

    Looking back at the figure showing the apparently enormous [and subsequently discovered to be erroneous] drop in sea ice, we se the magnitude of the drop is from about 14.5 to 13.8, or 0.7. (0.7/14.8)*100= 4.7%

    Am I missing something here, or would the addition of error bars obliterate all or most of any apparent differences between yearly averages (assuming the data isn’t corrupted to begin with)?

  166. Jeff (09:46:00) :

    Except that the graph in Dr. Meier’s post shows that the AMSR-E sea ice extent
    was virtually the same as the SSM/I sea ice extent until sometime in January.

    I agree, Jeff, and that’s all I meant – that there was probably something that Dr. Meier did not like at least right then in his above statement about AMSR-E, as derived simply from what he said right then in the quotation, without looking at anything else. I didn’t look, mostly because at first the graph wouldn’t download for me. I was just looking at words. As to what happens next, I just hope we don’t have to go through yet another round of Mannian reconstructions.

  167. hunter (08:53:59) :
    The pooint is that
    1) the data source is no longer credible

    Which data source would that be.

    I repeat part of my earlier post looking at 2 data sources:
    Please have a look at this comparison between AMSRE (JAXA site) and SSM/I (NSIDC) This compares monthly averages back to 2002. In general the AMSRE data is smaller than the NSIDC and the only significant time it is larger is in Sept 2008 when it is 170,000 sq km larger. A difference of 3.5% larger compared to AMSRE area at that time.

    There seems to be no significant drift visible in earlier data. There is an obvious difference in the algorithms used to genereate the 15% sea ice areas.

  168. So its official – we can no longer trust any of the data.

    i do not traduce the hard work of all involved – but we have been given data as fact and now we see how easy it is for that data to be so much junk.

  169. Again, thank you for Dr. Meier for listening and taking action. I look forward to reading your guest post.

    Anthony, someone commented about the possibility of restricting the length of comments. Please don’t. I learn so much from the longer, complex scientific comments. I wish I could add such relevant content myself, but my skills are limited to the tangible realm. If we do end up with another ice age, I’ll know which food crops to grow and how, and I’ll make sure we’re clothed and fed, that our homes are insulated properly and the flues draw.

  170. thefordprefect (03:24:29) :

    http://news.nationalgeographic.com/news/2000/12/122900inuits.html

    Global Warming Melts Inuit’s Arctic Lifestyle
    Lisa Krause (July 12, 2000)
    Traditionally, the 130 members of the Inuit community of Sachs Harbor, located on the western tip of Banks Island in the Canadian Arctic, supported themselves through age-old patterns of hunting, trapping, and fishing. Recently, however, members of the community have taken on a new role: climate-change observers.

    You’re data is outdated, see below. Apparently, as the polar bears moved north, they took 8 residents with them. Excuse me for being crass, but institute cap and trade for 122 people?

    Sachs Harbour is a hamlet located in the Inuvik Region of the Northwest Territories, Canada. Situated on the southwestern coast of Banks Island in Canada’s Northwest Territories the population according to the 2006 census count was 122 people.[1]

  171. What George Will wanted to say: “At the END of 1979 the size of the sea ice was equal to the size at the END of 2008″.
    What he said: “At the beginning of 1979 …. at the beginning of 2009″.
    The first version seems to be correct (an equal anomaly of about -0.5 million sq km).
    The second is wrong.

  172. the fordprefect,
    We know that the land stations are not reliable.
    That has been very well documented here.
    We now know that the ice data is not reliable.
    That is what this thread is about.
    We know that GISS data has not been trustworthy for quite awhile.
    The human interest story you posted is simply not credible, by the way.

  173. bluegrue (08:04:38) :

    You may want to have a closer look. I did not find the data, so I took the image, enlarged it and cut and pasted together the relevant parts. One day comparisons don’t prove a difference (the alleged “cherrypick” is the date of publication), but the data confirm the conclusion. Here’s 1979 and the last few years, blue is the sea ice area. Here is the collage:

    I’d be interested to get your definition of “at the same level”, Philip_B.
    ——————————

    Different Philip_B here, by the way..

    The Daily Tech article came out on January 1st so, using the exact same logic as Cryosphere, they chose the data at that time – which was probably December 31st, 2008 or maybe within a week prior to that. As you can see from your enlargement, but better still, from the lower red trace on the same graph, the levels of sea ice were identical at that time. This seems pretty newsworthy to me, and is probably why the article was written.

  174. hunter (12:30:15) :
    the fordprefect,
    We now know that the ice data is not reliable.

    comparison between AMSRE (JAXA site) and SSM/I (NSIDC) shows no significant drift between the two. Are you suggesting 2 satellites 2 different detectors are drifting simultaneously?

  175. Upon further investigation, we found that data quality had begun to degrade over the month preceding the catastrophic failure.

    Have they tried thumping it?

  176. HasItBeen4YearsYet? (09:32:59) :

    JUST ASKING….
    Error Analysis

    http://nsidc.org/data/docs/daac/bootstrap/index.html

    Under ideal winter situations when only thick ice and open water are present, ice concentration can be derived with Bootstrap technique at an accuracy of about five to 10 percent,

    This is sea ice concentration for a given location, not area or extent.

    It would be good, if Dr. Meier could address this aspect in his article, too.

    Here’s how I read this. The sensors have a resolution of about 25km x 25km, IIRC. Each of these squared makes up one grid point. The 5%-10% error refers to the error in sea ice concentration for each individual grid point. This error does not translate one to one to error in area, as only those grid points that are at the threshold to be counted as ice or water are affected. So yes, there is an error in the area, but it is far less than 5-10%, as most of the grid points counted as ice have much larger concentrations than the threshold value.

  177. MartinGAtkins (14:08:35) :
    Have they tried thumping it?

    Do you mean percussive maintenance? I can see it now; a robotic arm with a rubber fist fitted to all new satellites for just such an occasion. Of course it would need its own control system… maybe a Wii nunchuck?

  178. @ philincalifornia (13:36:56) :
    Sorry, you are confusing two articles here. In the passage, you have quoted above Cryosphere Today addresses an op-ed by George Will in the Washington Post on February 15, 2009, see below for more. The “Statement related to Daily Tech article of January 1, 2009″ is exactly that, addressing an article by Michael Asher entitled “Sea Ice Ends Year at Same Level as 1979”, published in Daily Tech on January 1, 2009.

    The op-ed by George Will, was published in the Washington Post on February 15. A copy of Will’s op-ed can be found here. He writes

    According to the University of Illinois’ Arctic Climate Research Center, global sea ice levels now equal those of 1979.

    “Now” as in “today, February 15, 2009″ or as in “this winter season”. Compare minimum extension and the point is made.

    It is disingenuous to compare transients as Asher does, as in this case the timing of sea ice increase and decrease within the season plays a major role. It weakened “Cryosphere Today”‘s argument to fall into the trap of doing a single day comparison, however mid-February happens to be near the annual minimum of global sea ice area. Compare the minimum values and tell me we are back to 1979 levels. Always keep in mind, this is area, not volume. 1979 was thick multi-year ice, 2009 is for large parts thin, one-year ice.

  179. @ Anthony
    As you can see above, once more I have managed to botch an HTML tag. There is a WordPress plug-in that gives readers a live preview of their post, so they/I can catch these errors much better.

    http://wordpress.org/extend/plugins/live-comment-preview/

    Could you consider to give it a try?

    REPLY: for the thousandth time, this website is free hosted on wordpress.com. They do not allow me to install plugins. People, I know you want preview but get over it. Not gonna happen until I move off to a dedicated server…and I’m not ready to do that. I have enough work as it is without adding server management to it. – Anthony

  180. bluegrue (15:05:50) :
    @ philincalifornia (13:36:56) :
    Sorry, you are confusing two articles here. In the passage, you have quoted above Cryosphere Today addresses an op-ed by George Will in the Washington Post on February 15, 2009, see below for more. The “Statement related to Daily Tech article of January 1, 2009″ is exactly that, addressing an article by Michael Asher entitled “Sea Ice Ends Year at Same Level as 1979”, published in Daily Tech on January 1, 2009.

    The op-ed by George Will, was published in the Washington Post on February 15. A copy of Will’s op-ed can be found here. He writes
    According to the University of Illinois’ Arctic Climate Research Center, global sea ice levels now equal those of 1979.
    “Now” as in “today, February 15, 2009″ or as in “this winter season”. Compare minimum extension and the point is made.

    It is disingenuous to compare transients as Asher does, as in this case the timing of sea ice increase and decrease within the season plays a major role. It weakened “Cryosphere Today”’s argument to fall into the trap of doing a single day comparison, however mid-February happens to be near the annual minimum of global sea ice area. Compare the minimum values and tell me we are back to 1979 levels. Always keep in mind, this is area, not volume. 1979 was thick multi-year ice, 2009 is for large parts thin, one-year ice.
    —————————————

    I didn’t confuse the two articles. I was fully on top of them both. We don’t know exactly to which point George Will was referring in his article. It would seem from his conclusion that it was likely to be December 1979 and December 2008. I agree that the use of transients is not the best method, but I myself was struck by the essentially exact match of sea ice levels in those two years.

    Can you point me to a good, real reference on ice volume, or is that statement just from a hypothetical or a model ?? Let’s face it when the planned studies on ice thickness and volume are completed (this year?) we know exactly what their “data” will say. I could probably write the abstract and preordained conclusions for them today, along with the newspaper headlines.

    Anyway, perhaps our initial disagreement is mooted by the fact that the sensors appear to have been dysfunctional for who knows how long ??

  181. Mike Borgelt (05:04:44) :

    Beat off polar bears with shotguns? A shotgun is likely to only irk a polar bear. A .50 cal Barrett semi auto rifle is more like it.

    Actually, yes, that is what they do. Use a shotgun to simulate a hive of bees attacking the bear (couple hundred shot hitting simultaneously), and the bears cut & run. I hear it’s quite effective.

  182. Can ANYBODY tell me if there is any substance to the increase of cosmic rays (as in the levels reported by the Neutron Monitors) causing increased damage/shorter life span of space-borne instrumentation?

  183. I have spent my entire life working with extremely sensitive instrumentation, from ion chambers. photomultipliers, gamma spectrometers, IR analysers, magnometers, gas chronometers, cryogenic neutron detectors, scintillation detectors, and on and on. All of these devices require rigorous programs to detect and correct for instrument drift. Without an effective program, received data is only so much DANGEROUS garbage. This might be excusable, if the error existed for minutes, hours or possibly days, but for weeks, possibly months or more, is incredible. It is indicative of systemic incompetence which would seem incongruous with the space program. It would be akin, to blaming the recent nuclear sub collisions, on compass drift. Try explaining to a cop that you were driving at 120 mph in a 30 mph zone due to speedometer drift. I find the laissez faire attitude of the scientific community incredulous. What if this had been a missile launch detection channel.

    I for one, will be demanding a full scale, transparent, investigation into what is going on and who is responsible. Dr. Walt Meier has much more explaining to do!

  184. Robert Bateman (20:04:12) Here in western Colorado, the DOW hands out shotgun shells with rubber shot. At 10 yds a round to the tush works well from personal experiance. Actually, just yelling and making a lot of noise usually works. I ran into problems with ‘relocated’ bears that had caused problems elsewhere in more populated areas. They are tagged and sent to the sticks. They learn that trash cans and birdfeeders are food sources, and seek them out. I was getting bears with two tags that didn’t care a wit about noise. I wondered if the DOW was hoping that someone out here would just shoot them so they wouldn’t have to deal with them anymore.

  185. philincalifornia (19:48:32) :

    We don’t know exactly to which point George Will was referring in his article.

    The op-ed was published on February 15. Any reader would have assumed that “now” is either today or this season, in the latter case it would have to be something significant like minimum extent or such. Why on Earth, should any reader not familiar with the data come to the idea, that “now” is meant to be the exact date December 31?

    but I myself was struck by the essentially exact match of sea ice levels in those two years.

    As long as there is an overlap in data range and a few weeks jitter in the freeze/thaw cycle, this is inevitable. Let me illustrate this with some made-up data, values for mid-month:
    Year X Year Y
    Sep 16 14
    Nov 17 15
    Dec 14 14
    Jan 10 12
    Feb 12 8
    Mar 14 10
    Year Y has lower maximum and lower minimum area. They still have exactly the same area in mid-December. The only difference is that year X had its minimum earlier. Would you consider this significant? Would you consider the description “area in year Y is at the same as the year X”? This is the kind of cherry-picking done by Asher, and possibly parroted by Will.

    Can you point me to a good, real reference on ice volume, or is that statement just from a hypothetical or a model ?? Let’s face it when the planned studies on ice thickness and volume are completed (this year?)

    Area is smaller, thickness is less (from declassified submarine data). Hard to miss the conclusion of volume loss. You won’t go anywhere without at least some modeling. There’s an essay on NOAA on the topic. Or you could just go for primary literature by a search on scholar.google for “sea ice volume”. Has Arctic Sea Ice Rapidly Thinned? in Journal of Climate looks interesting, keep in mind it’s from 2002 and only covers data up to 1997. It finds that in 2000 volume was comparable to 1950s levels (it was up during the 60s and 70s), but shows a deep decline during the last two decades (16% to 25% from 1987 to 1997). From my reading of more current data, this trend should hold in this century, too.

  186. Try explaining to a cop that you were driving at 120 mph in a 30 mph zone due to speedometer drift.

    It happens. Not to the egregious level you describe, but it happens. I was pulled over for doing 65 in a 55, when my speedometer read 56. Had it put on a dynamometer and the speedometer was off by 9 mph at 60 mph. Whether it was always that way, I don’t know. I would guess not since I hadn’t gotten pulled over a lot.

  187. bluegrue (08:47:36) :
    philincalifornia (19:48:32) :

    ….. Would you consider the description “area in year Y is at the same as the year X”? This is the kind of cherry-picking done by Asher, and possibly parroted by Will.
    ————————————

    …. and don’t forget the people at Cryosphere today who did exactly the same thing, before, apparently, removing their comment.

    Thanks for the links I shall read them. From the title of one, it looks like this will pertain to the Arctic only, and not global ice volume values.

    Since you seem to like the minima, is there a plot of global minima together with error bars and best fit trend line ?? 1972 – 2008 (2009?) would be good if the data back to ’72 is available. Surely someone would have done that plot, although your earlier comment about having difficulty finding data might imply that maybe that’s not the case.

  188. I don’t “like” minima, it’s just that minima and maxima are reasonable choices, if you want to compare sea ice in different years. What about shared work? You find the data for the global sea ice coverage used by Cryosphere Today for their global sea ice coverage plot in ASCII format and I’ll do the minimum hunt and trend line.

    BTW, why do you think that global sea ice coverage is a good metric for climate change? GCM’s show that we are to expect changes in the Arctic, but in the Antarctic the trend is undecided between models.

  189. Anthony,
    Can you explain the inconsistency in the AMSR-E data on the website? The chart above comparing AMSR-E data to the failing SSM/I data indicates close to 15M square KM. The chart normally posted in the margin shows around 14M square KM. Both charts indicate AMSR-E is source of data. Here’s the two hyperlinks.

  190. bluegrue (11:21:38) : wote:

    BTW, why do you think that global sea ice coverage is a good metric for climate change? GCM’s show that we are to expect changes in the Arctic, but in the Antarctic the trend is undecided between models.
    ——————————————-

    I’m not expert enough to think either way, but that’s my favorite graph on the Cryosphere site. I wish they would show the 1972 data to 2009 if they have it (and when they’ve fixed the 2008/9 problem – if they ever can ever retrieve the real data).

    Also, it would be nice if they would give additional mean lines to see the comparison between say 1972 – 2008, or 1979 – 2008.

    I’m also intrigued by the fact that if you were to plot the minima as I suggested in my previous post, by eyeballing, it looks like it would be essentially flat. I find this strange, given that most people, myself included, are in agreement that the planet is in a general warming trend as it comes out of the LIA and, as a scientist in a different field, I’m intrigued about what the explanation might be (conclusions that fit the empirical data, not models).

    Then of course, there’s the other elephant in the room, which is why do Cryosphere Today and, with respect, you to a certain extent want to steer the discussion away from, for example, a flat or flattish line.

    I suppose I could’ve just answered your question more directly by saying that I think global sea ice coverage is a good metric for climate change because I’ve been bombarded by the media with it for the past 5 – 10 years.

  191. BTW, why do you think that global sea ice coverage is a good metric for climate change?

    One obvious rational is that albedo changes are more closely tied to Ice cover than they are to ice volume. If the change in albedo is an important factor in the global heat budget it might be the best measure if as is often stated that the arctic ice functions as the canary in the coal mine and warns of subtle changes.

    Here is one project to get good field data on ice thickness/volume using ice penetrating radar to compare numbers to submarine data.

    http://www.javno.com/en/world/clanak.php?id=233610

    One question of course, is that since this is floating drift ice, you can never measure the same piece two seasons in a row so at best this ice volume data will be the basis for an “estimated volume”.

    It will also be interesting to see if the melt off leads to very fast ice build up due to rapid surface freeze followed by wave and wind stacking of the thin ice layers and then additional freeze on water opened up due to the stacking and compression of that relatively thin ice.

    Open water will obviously cool much quicker than water covered by thick multi-season ice, so the recovery of both surface area and volume might allow for very rapid recovery of ice volume following a large melt season.

    Larry

  192. I WONDER IF THE RECOMMENDATIONS NOTED HERE HAVE BEEN ACTED ON?

    http://www.the-cryosphere.net/3/1/2009/tc-3-1-2009.pdf

    5 Conclusions
    In situ sea ice data taken from the 2006 cruise aboard the
    Oden were compared with satellite data from the same period.
    Good agreement was found between ship observations
    of ice edge position compared to NIC ice charts derived from
    high resolution satellite imagery. Passive microwave imagery
    alone, however, provided less agreement with ship observations
    and, therefore, NIC ice charts, with a strong bias
    toward underestimating the area bounded by the ice edge using
    passive microwave.

    . . . . .
    . . . . .
    We recommend that with the available records from
    scatterometer and active radar data that are approaching ten
    years, that a reanalysis of the Antarctic sea ice extent, compared
    to the passive microwave record over the same period,
    may be a prudent approach to verifying, and perhaps correcting
    that climatology.

    NOTE TO bluegrue (14:28:25) : — bias doesn’t get avearged out.

  193. ….or, should I say, will they be acted on, as that paper is very recent – guess they have to fix the thing, first.

  194. Well, the butterfly has moved on. However, major melting in four spots along the Russian coast. And also west of Greenland, Hudson’s Bay and the Sea of Okhotsk. Oh, the horror!

    http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=02&fd=20&fy=2009&sm=02&sd=21&sy=2009

    Should we start a pool to guess when the two scientists at Cryosphere pull the plug on the current data stream?

    REPLY: A better pool would be to bet on when they’ll fix this statement under the images:

    “Note – these missing swaths do not affect the timeseries or any other plots on the Cryosphere Today as they are comprised of moving averages of at least three days. ”

    - Anthony

  195. @ HasItBeen4YearsYet? (23:20:35) :
    Thanks for the link to the paper. I’d like to add some more quotes to give a better context. The paper compares NIC ice edge data derived from high-resolution satellite images, passive microwave imagery of AMSR-E and ship observations. From the intro

    We also found that the NIC sea ice edge agrees well with ship observations, while the AMSR-E shows the ice edge further south, consistent with its poorer detection of low ice concentrations.

    From the conclusions

    We infer the passive microwave imagery has this resolution bias due to the low emissivities typical of wet snow covers and surface flooding, as well as low spatial resolution of small ice bands and low concentrations of dispersed small floes in the ice edge region. In areas of higher concentration in the interior pack, however, there is an indication that ship track bias to travel preferentially in the open water areas, as well the under sampling of a pixel (156 km2) by a single ship observation (1–3 km2) in highly variable summer conditions contributes to ship data under predicting ice concentration over the wider region. The result is a generally low overall correlation (R2=0.41) between ship estimates of ice concentration and passive microwave derived values.

    There is not only passive microwave bias to be aware off, it would have been nice, if you had not skipped that part. In the discussion they also note, that agreement between passive microwave and ship observation is much better in winter conditions than in summer conditions as reported in this paper.

    I never claimed that the error averages out, no idea where you got that from. As far as I am aware, sea ice area counts all grid points with an ice concentration above a threshold level. Grid points with concentrations near threshold level (above or below) are far less numerous than those with concentrations safe above that threshold. So a 5-10% error in concentration does not translate to a 5-10% error in area. That was my point.

    Bias was to be expected. As long as it is a consistent and not a time variable bias, it should have little influence on the trend in ice area. And yes, you may see an impact on the trend, when large areas become much thinner or more dispersed. This would result in less ice area reported.

    We recommend that with the available records from scatterometer and active radar data that are approaching ten years, that a reanalysis of the Antarctic sea ice extent, compared to the passive microwave record over the same period, may be a prudent approach to verifying, and perhaps correcting that climatology.

    I’m looking forward to the results.

  196. philincalifornia (15:27:42) :
    Are these charts good enough for you?
    NSIDC sea ice extent.
    They’ll give you trends for arbitrary months and both hemispheres, so you can compare apples to apples. The linear trends are reported including the error (not sure whether it is one or two sigma). Global data can be found following the “Access Data” link on this page.

    I suppose I could’ve just answered your question more directly by saying that I think global sea ice coverage is a good metric for climate change because I’ve been bombarded by the media with it for the past 5 – 10 years.

    Maybe you ought to lose that media filter and look either into the IPCC reports or primary literature instead. If you are willing to trust the short version as written by some pixels on your computer screen: Arctic sea ice loss is expected, Antarctic sea ice trend undecided amongst models, as e.g. increases in temperature lead to increases in precipitation (snow) and you have to factor things in like the Antarctic Circumpolar Current.

  197. Should we start a pool to guess when the two scientists at Cryosphere pull the plug on the current data stream?

    REPLY: A better pool would be to bet on when they’ll fix this statement under the images:

    “Note – these missing swaths do not affect the timeseries or any other plots on the Cryosphere Today as they are comprised of moving averages of at least three days. ”

    I took a brief look at some of the plots for the various basins and saw some suspcicious declines. It would be a good thing to review tomorrow morning before the work day begins.

    A fetch of one plot reported “Last-Modified: Sat, 21 Feb 2009 16:54:31 GMT” so maybe this afternoon or evening would be as good. OOPS – I just realized I didn’t submit this. A fetch just now reported Sun, 22 Feb 2009 16:54:32 GMT.

    P.S. Sorry about posting here, this belongs in http://wattsupwiththat.com/2009/02/20/sea-ice-sensor-degradation-hits-cryosphere-today/ of course. All: please post followups there.

  198. bluegrue (08:51:26) :
    philincalifornia (15:27:42) :
    Are these charts good enough for you?
    NSIDC sea ice extent.
    ———————

    They’re great. I know, I should’ve been able to find them myself, so thanks for saving me the trouble.

  199. James P (07:11:51) :

    I’d love to know if this affects the reported state of the Northwest Passage.

    I hear of record low temperatures in Alaska, but there is also this:

    http://www.canada.com/news/Northwest+Passage+unprecedented+melt+Experts/836501/story.html

    Does anyone, preferably on the ground, know what is happening?

    Your link goes to a September 25th column. I think Mark Serreze’s “It’s open” comment came weeks before.

    These folks were there, it was not an easy sail:

    http://awberrimilla.blogspot.com/search?updated-max=2008-08-15T19%3A16%3A00%2B01%3A00&max-results=50

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