Nicks in the myths of time

Baby stars, as seen by the Hubble telescope

I want to revisit some false arguments fabricated ages ago by our critics: time-worn errors which need re-rebutting, because they are still surfacing. These smooth myths, one might say, are nicked all over with imperfections. And mists cover everything.

The main spurious argument holds that the Climate Science Coalition says there’s no reason to adjust the raw temperature readings. That is false: we think there are good reasons for adjustments. What we actually say is that NIWA has made changes but refuses to reveal what they are.

A related myth is that NIWA has given us everything we asked for — simply by releasing the net arithmetical adjustments to each station. The reality is that, first, a net change isn’t enough because there could be multiple changes at a station. Second, the number by itself is useless; any reviewer needs the reason for each change. This is what NIWA has refused to tell us, yet both bits of data are required for any independent assessment of the accuracy of the temperature record.

To be fair, NIWA eventually agreed to “recreate” the list of reasons, but after many months they haven’t delivered it.

We can’t disagree with the changes — we don’t know what they are

Our critics hector us to create our own version of the NZ temperature record, arriving at whatever adjustments we think best, and publish it. That’s not a bad idea, but it is a myth that this might answer the questions we’ve put to NIWA. How could it? Only they can describe the changes they made. Isn’t that self-evident? The call for us to create our own Schedule of Adjustments deliberately mistakes what we have said.

We don’t disagree with NIWA’s changes because we don’t know what they are, so there’s no reason to provide another version. When their changes are revealed, we may or may not disagree with them, but we will, of necessity, stop asking for them.

These myths arise from a misinterpretation of the paper we published last November, Are we feeling warmer yet?, which questions the official national temperature graph produced by NIWA (available on their web site).

NIWA’s undocumented changes are the sole source of warming

Our paper shows simply how the adjustments made by NIWA to the raw temperature readings are not documented and yet those changes alone are responsible for the warming trend seen in the graph, because there is little trend in the raw readings. So we asked NIWA for the adjustments and why they made them. They eventually admitted that they couldn’t tell us what they are because they no longer had them.

In an email to me dated February 4th this year, James Renwick said:

Yes, the “original worksheets” used by Jim Salinger for his PhD study in the late 1970s have indeed been misplaced, or possibly destroyed. However, the original data upon which his calculations are based are still in existence. We are in the process of re-creating Jim Salinger’s work, and of documenting the adjustments necessary to the various stations – as we indicated in a media release in December. We can check our overall result against the Salinger NZ time series, to see if we get the same answer.

You’ll notice the message is ambiguous about exactly what was lost or not lost. Four days later he clarified his meaning with this message to me:

I think you misunderstood my mail last week – the original SOA [Schedule of Adjustments] isn’t gone, it was published in Jim Salinger’s PhD thesis, and has been used in NIWA for many years. What’s “gone” are “the original worksheets”, i.e. Jim Salinger’s working notes from this PhD study. But the results (the SOA, etc) are in his thesis.

Which provides no real clarification. Because, despite the fact Dr Renwick claims the “results (the SOA, etc)” are “in” Salinger’s thesis, NIWA has never provided a separate description of those results. More significantly, scientists in the Coalition, who finally obtained a copy of the thesis to study, cannot extract from it a proper SOA. They cannot understand what Salinger did!

The simple truth

Gareth Renowden, at Hot Topic, does not understand that important aspect of the Coalition’s research nor the deficiencies we found in the thesis. He said this to me the other day:

You attempt to defend the indefensible, and sophistry will get you nowhere. It’s quite clear what you meant. Had you examined the station histories, you would have found ample justification for the corrections that were made — but that didn’t play to the narrative you wanted to establish, which was that warming was an artefact of the adjustments rather than a physical reality.

No, it is not sophistry but the simple truth. Gareth seems determined to believe what he likes, whatever I say now. For notice that we did examine the station histories and found them unremarkable:

Have the readings in the official NIWA graph been adjusted? It is relatively easy to find out. We compared raw data for each station (from NIWA’s web site) with the adjusted official data, which we obtained from one of Dr Salinger’s colleagues. Requests for this information from Dr Salinger himself over the years, by different scientists, have long gone unanswered, but now we might discover the truth. What did we find? First, the station histories are unremarkable. There are no reasons for any large corrections. But we were astonished to find that strong adjustments have indeed been made.

Anyone can do the same: go to the Climate Database web site, download the station histories, examine them — then disagree with us if you like, but first examine the histories!

Publish the methodology — we dare you!

Anyone can similarly obtain a copy of Salinger’s thesis: go to Wellington, apply at the VUW library for the single copy they hold, don’t expect to take it home, because they won’t let you, and have a look at it. Then publish the description of the methodology you will no doubt find therein! We dare you!

To repeat it yet again, NIWA have never described the methodology required to replicate the seven-station series. None of the citations they have given in press releases, on their web site or in answers to questions in the Parliament describe precisely what Salinger did and why.

It is a myth that the Coalition “knows” everything required to replicate Salinger’s work.

For those who disagree

Here is a challenge: using only the references on this NIWA web page, but starting with the “raw” data downloaded from the Climate Database, produce and publish the official version of the NZ temperature series.

Bet you can’t do it.

Oh — and Salinger’s so-called “methodology” has never been published in a peer-reviewed journal. There has to be a reason for that.

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13 Thoughts on “Nicks in the myths of time

  1. Flipper on 22/08/2010 at 7:45 pm said:

    Nice piece Richard.
    As always, Renowden will love you for that. However, one imagines that when the NZCSC application for review is heard in the High Court, VUW will be required, by court order, to produce the Salinger thesis . ( I dont think copyright trumps court proceedings but will bow to an authority on that.) The matter will then become one of public review and, under cross examination, produce a situation where Renwick, Wratt et al will not be able to use Renowden as a “diversionary tactic” to hide their malfeasance. Bring it on. It should be fun.

    Incidentally, I was silly enough to take a peek at Hot Topic the other day. What a waste of time. I had not realised that those AGW ” religious” zealots/cultists took themselves quite so seriously. They are flying the names of discredited folk (Schneider et al) as if they were the battle pennants of a crusade.
    The Flat Earth Society would be proud to welcome them as members.

  2. Huub Bakker on 22/08/2010 at 9:37 pm said:

    Much as I would like to reproduce the Seven Station Series, I have not yet been able to find a list of stations included in it. I could compare all the possibilities but presumably this has already been done or is mentioned somewhere on the NIWA site.

    Downloading the SSS spreadsheet from the NIWA site is unhelpful since it is a composite after adjustments have already been made.

    Do you know where I can find the station list?

    • Yes, good question. You need the station ID numbers, which NIWA don’t seem to provide. I’ve got it around here somewhere. I’ll get back to you tomorrow.

    • Huub,

      NIWA provide a document titled The NIWA “Seven-Station” Temperature Series, dated 9 February 2010, which gives the station IDs (NIWA calls them Agents) for all the weather stations involved in the seven-station series. It turns out that about 32 individual weather stations contributed.

      You can download the pdf from http://www.niwa.co.nz/__data/assets/pdf_file/0017/101834/7-Station_Temperature-Series.pdf
      or http://tinyurl.com/254akhc

      Curiously, I notice the link to this document at http://www.niwa.co.nz/news-and-publications/news/all/2009/nz-temp-record/seven-station-series-temperature-data
      is shown under the heading “Schedule of adjustments” (which is what attracted me to it).

      But it provides only the numerical adjustments — there are no reasons given for any of them.

      Still, good of them to make this info available, even if it took pressure from ACT and the Coalition to make them do it.

    • Huub,

      About Ken. We’re old friends. I suggest you ask him:

      1. Have you (finally) worked out your own SOA from NIWA’s raw data and what are they?
      2. Have you read the post above, and have you noted the parts explaining how the methodology is inadequately described and not used by anyone?
      3. Have you asked NIWA to describe the adjustments they made to our temp record and what did they answer?

      And then welcome him back to the Climate Conversation. It’s nice to hear from him again.

  3. Huub, the NIWA site has a link to their database. All the raw data is there.

    You need to register and can then download all you want and play with it to your hearts content.

    If you want to have a go at working out your own adjustments (which are necessary to get a record over time – don’t beleive anyone who clai9ms otherwise) there is a link on the NIWA site to publications which include methodologies for doing that.

    You will have to make subjective decisions about which method to use in each case and it will take a lot of work. But if you do this honestly I am sure your results will be similar to NIWA’s.

    • Huub Bakker on 23/08/2010 at 11:03 pm said:

      Ken,

      As a Professional Engineer with a PhD in Process Control, I have looked on with interest as questions are raised in New Zealand, Australia, the USA and elsewhere about the temperature record. I can see the necessity for making adjustments as well as the subjective decisions that need to be made along the way. What has surprised me has been the nature and magnitude of many of the adjustments as well as the uniform unwillingness of the various climate-monitoring organisations to publish the specific reasoning behind the individual adjustments. From where I stand I can see no legitimate reason for not publishing them and good reasons to do so. Surely not every single climate-monitoring organisation finds itself without documentation describing the adjustments!

      Imagine my interest then when I read about the First Differences Method and its ability to objectively remove the effects of Time-of-Observation, site moves, equipment changes and other such step changes. I have implemented this on the seven centres noted in the Seven Station Series and can now see some of the issues in using this method. However, in light of the lack of an SOA there seems no other means of validating the SSS and the New Zealand Temperature Record. Certainly using an alternative method of creating a temperature series will provide a useful test.

      I’m grateful to Richard for finding the station list for me and will attempt to replicate the SSS although I will also attempt to use as many of the neighbouring stations as possible since the FDM does not handle small numbers of stations very well.

      As for doing this honestly, I’m doing it blindly at this stage, which amounts to the same thing! 🙂

    • Good to see you accept the need for adjustments, Huub. Some local people have been trying to pretend they were not necessary – for their own political reasons of course.

      However, if you haven’t already I suggest you check out the paper the NIWA site refers to. Several different methods were used for calculating adjustments – average nearby station data was only one of them. And of course that would not be appropriate in every case.

      Also, be a bit careful of Rchards data on the stations – check the NIWA database. I have found some difference between his data and the official NIWA data and suspect he has obtained some of his from different sites or sources (eg. monthly temperatures instead of annual, or old data which has since been removed).

      What do you intend to do with your results? Any plan for inviting peer review? For publishing?

    • Huub Bakker on 24/08/2010 at 6:56 pm said:

      Ken,

      I have downloaded all my data directly from the NIWA database and I see that there are one or two corrections made this year. I have found in the climate debate that it pays to get as close as possible to the source. It was the station ID’s that I was particularly after as there was no way to tell which stations to include otherwise. Richard pointed me to the paper on the NIWA site and I am now following that.

      I’m somewhat surprised that my initial picks are so different from NIWAs. I chose the oldest station as a base and then looked for any stations within a 10km radius, picking the ones that were closest and provided the necessary coverage over time. I know that some stations are more reliable than others but I don’t know how to find that from CliFlo; the descriptions as 1:Climat (Standard) etc don’t tell me much.

      When I have something that looks reasonable (i.e. I’ve got all the data correct, located the possible step changes, have applied the FDM method correctly and don’t have any obvious errors) I thought I’d see if I could get it posted on the blogosphere somewhere. I don’t have the time, inclination nor pedigree to write it up as a proper paper and I’ve found that the blogosphere provides lots of comments, much of it useful. 🙂 I will, of course make all my code available if that is the case.

      I’m sticking with annual data at the moment but, from the comments on the ClimateAudit post (http://climateaudit.org/2010/08/19/the-first-difference-method/) there is utility in using the monthly data since it essentially gives you 12 estimates of annual differences albeit with more noise. Too much work at the moment though.

  4. Quentin F on 23/08/2010 at 3:23 pm said:

    Did anybody attend the climate debate at the University of Auckland on Aug 19th (I think)? Salinger was there, according to the information I received. I couldn’t go unfortunately.

  5. Quentin F on 24/08/2010 at 3:25 pm said:

    I suspect the whole record is flawed anyway, going on how the rest of the world’s data seems heading that way.

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