1. Does the data with adjustments for NZT7 get passed through a homogenising process or can one take the raw data, add in the adjustments and reproduce their graph.

The raw data are available in the NIWA CliFlo database. It’s free, but you have to register to get a login. The homogenising adjustments for their new NZT7 (as opposed to the old and now defunct 7SS) are documented on their website here. the spreadhseet containing just the adjusted data is here.

2 has anyone analysed the validity of the NZT7 adjustments, if so, is that analysis available.

There is some work going on in this area, but as we don’t have the sources of taxpayer funds available to NIWA, it’s slow going.

1. Does the data with adjustments for NZT7 get passed through a homogenising process or can one take the raw data, add in the adjustments and reproduce their graph.

2 has anyone analysed the validity of the NZT7 adjustments, if so, is that analysis available.

http://flay.jellybee.co.uk/2011/01/dealing-with-denialists-delingpole-part.html

Your organization has achieved a positive result and I think you should be proud of that, but you should limit your representations of success to reality.

Thank you. I apologise if I appeared to go beyond reality; it was unintentional. Perhaps the ego takes a while to forgive those who trample it; those slights to our scientists and cynically incorrect citations were deeply felt discourtesies which have not been followed by an apology. These were public scientists behaving badly.

You ask why would the NIWA throw out the old series unless it was faulty. I think that’s explained very well here:

and you link to my press release of 11 Oct 2010. Tactical error or not, the series contained real errors and could not be justified because: 1) the (unpublished) methodology was too subjective; and 2) the actual workings had been lost, so the precise reasons for the adjustments could not be replicated in answer to our questions.

However, NIWA did not admit that (which would have been the truthful, simple course) but chose to obscure it and work toward reconstructing the series. That’s annoying, coming from public servants!

You may not be aware that the original graph has been used for many years as the official graph. NIWA cited it constantly on their web site, in environmental hearings, court cases and in advice to the government of the day. When they suddenly declared it “unofficial” to the High Court, it surprised everyone. It seemed to be a cynical manoeuvre to avoid taking responsibility for the graph’s deficiencies.

Again, an unacceptable strategy from our public servants.

This is the crux of the issue.

1) NIWA tout the 0.91C/century obtained from the linear trend as being representative of NZs temperature when clearly an extrapolation of that trend back 100 years leads to an unrealistic prevailing climate as will extrapolating that trend 100 years into the future .

2) The trend is selectively obtained as the quote alludes because if data for say 50 years prior to the start of the 7SS is included, the 0.91 slope would be no longer valid.

3) If variations in time of NZ temperature are “not completely uniform” then why is a linear trend applied and not some other statistical best fit e,g. EMD.

4) The downward adjustments to the raw data are the origin of the trend so “unequivocal” 0.91C/century warming is purely an artifact of the adjustments.

5) The 0.91C/century trend is inconsistent with the longer-term SH trend, the reason for that is most likely as for 2) above.

6) If the NZTR is detrended to account for the normal warming since 1850 as a result of solar variation and astronomical cycles and therefore internal climatological variation (for which there is ample scientific support), the trend since 1960 is decelerating rather than accelerating and could even be cooling, but application of a linear trend as the first and only statistical step will not reveal the inherent trend.

“But now, para 7(a) of NIWA’s Statement of Defence: http://tinyurl.com/23eplfy

states that “there is no ‘official’ or formal New Zealand temperature record”.

In para 8(b) it says the NZTR is not a public record for the purposes of the Public Records Act, using the exemption of “special collections” defined (in para 4(b)) as non-public records used for “research purposes”.

In para 4, NIWA denies it has any obligation to use the best available data or best scientific techniques, while conceding that it has statutory duties to pursue excellence and to perform its functions efficiently and effectively.

The juxtaposition of these conflicting stances leaves NIWA looking decidedly awkward. Should it go all out to defend its most famous product, or throw the NZTR under a bus? ”

They took a line of defence that ultimately made it awkward to continue to hold onto the old series. A tactical error perhaps. Since Salinger’s original calculations had been lost they were forced to perform a new analysis. This is unfortunate, but ultimately to everyone’s benefit. Your organization has achieved a positive result and I think you should be proud of that, but you should limit your representations of success to reality.

You say that NIWA is guilty of impeachable acts. I agree. But what acts?

I did not imply, but stated outright, that the new graph demonstrates no significant warming after about 1960. NIWA agrees with this, giving the explanation that you educe in your quoted extract from the review, of altered air flow. But you also describe this as “patently false.” You present a contradiction.

I made no allegation of faking records—those who did should set the record straight. I referred to little warming after 1960, and that is true. The evidence for that is in NIWA’s new graph. In a graphical sense, they “said” it.

By the way, I’m looking forward to comments from our independent scientists, who can help we amateurs understand the science in NIWA’s review, including the statements you quote on wind flow. Until then, I’ve no idea whether they’re correct or even reasonable.

Please remember that I’m not taking issue with NIWA over the conclusion of warming over the 100 years of the series. We (our scientists) have to examine the series. If they’re happy with NIWA’s work, we’ll go quiet, I promise.

But they have swapped one set of adjustments for another without explanation or apology. That is wrong.

http://www.niwa.co.nz/__data/assets/pdf_file/0010/108928/OverView-7Stn-Series-web.pdf

“Although a linear trend has been fitted to the seven-station temperatures in Figure 2, we know that the variations in time are not completely uniform. For example, a markedly large warming occurred through the period 1940-1960. These higher frequency variations can be related to fluctuations in the prevailing north-south airflow across New Zealand. Figure 3 shows such a comparison, where the Northerly Flow Index is calculated from the Chatham Islands minus Hobart pressure difference (the reverse of the more commonly used Trenberth Southerly Index (Trenberth, 1976)). Again, there is very strong agreement between the seven-station temperatures and completely independent surface pressure measurements. Temperatures are higher in years with stronger northerly flow (more positive values of the Index), and lower in years with stronger southerly flow (more negative values of the Index). One would expect this, since southerly flow transports cool air from the Southern Oceans up over New Zealand.

The unusually steep warming in the 1940-1960 period is paralleled by an unusually large increase in northerly flow during this same period. On a longer timeframe, there has been a trend towards less northerly flow (more southerly) since about 1960. However, New Zealand temperatures have continued to increase over this time, albeit at a reduced rate compared with earlier in the 20th century. This is consistent with a warming of the whole region of the southwest Pacific within which New Zealand is situated.”

The representations you have made to the press have caused some outlets to report that scientists in New Zealand have admitted to faking temperature records and that new records show no warming. This is a charge of dishonesty and is itself untrue. Would you be willing to set the record straight?