Wherein we rebut Points 7, 8 & 9
In What Mullan actually says on 7 November I answered the Hot Topic post Danger Dedekind heartbreak blah blah of 5 November, in which Mr Gareth Renowden, presumably advised by Dr Brett Mullan, principal climate scientist at NIWA, had levelled criticisms at the recently published reanalysis of the NZ temperature record. I set out to identify clear, falsifiable statements that Gareth Renowden (or Brett Mullan) was making. There were nine debating points, which you can find in What Mullan actually says. We promised every one would be rebutted.
Point 7
Dedekind tries [sic] hand wave away the 11SS as having been “thoroughly debunked elsewhere”, but doesn’t link to any debunking. The fact is that the raw station data from rural sites with long records that require no adjustments show strong warming. In other words, the warming seen in the 7SS is not an artefact of site changes or urban warming. That is an important matter, and should have been addressed in dFDB 2014.
Debating point 7. The 11SS is an important record and has not been debunked.
Rebuttal
UPDATE 15 Nov 2014 1845 NZST
- Fixed the typo in the last paragraph. Now shows 0.28°C/century warming.
The 11SS is an embarrassment. It was thoroughly debunked as long ago as June 2010 in New Zealand Climate Crisis Gets Worse. That article comments:
“It is almost impossible to avoid the conclusion that NIWA’s political urge to prove a warming trend overcame its professional urge to apply objective scientific principles in constructing a sound and defensible temperature series.”
This is supposed to be a collection of sites that required no adjustments between 1931 and 2008, because there were no significant site or environmental changes.
In fact, every one of the eleven stations underwent changes, some of them huge. Six of the sites didn’t even exist before WW2. Tauranga moved across the harbour to Mount Maunganui. Molesworth’s 1994 change was terminal—it went out of existence. Queenstown’s environmental problems were so bad that Salinger wouldn’t attempt homogenisation in 1992.
The 11SS is a very useful corroboration of the 7SS if confined to the 45-year period that the eleven stations all existed. From 1949 to 1994, the eleven stations did indeed require no adjustments and, revealingly, showed a temperature rise at the rate of 0.18 0.28°C/century.
Point 8
Brett Mullan’s 2012 paper Applying the Rhoades and Salinger Method to New Zealand’s “Seven Stations” Temperature series (Weather & Climate, 32(1), 24-38) deals with the correct application of the methodology described in Rhoades and Salinger’s 1993 paper.
At the very least, dFDB 2014 should have addressed the existence of Mullan’s paper, and explained why the application of RS93 in that paper is not preferable to their interpretation of it.
Debating point 8. The de Freitas et al. (2014) paper should have discussed the relevant literature, including Mullan (2012).
Rebuttal
Mullan (2012) is not relevant literature.
In our paper we are at pains to make clear that our aim is to follow RS93 exactly when performing our reanalysis, and that is what we did. Mullan (2012) suggests possible modifications to RS93 (using very long time periods) based on certain samples from the 7SS. It does not address an interpretation of RS93, but sets out the author’s personal perspective on what RS93 should have proposed.
Criticising or modifying RS93 in any way was not within our purview, so Mullan (2012) has no relevance to the journal paper.
Point 9
Dedekind makes much of the fact that the paper does refer to one paper on SSTs around New Zealand — but skips over the essential point: that the SST evidence confirms that warming is occurring faster than they calculate.
Debating point 9. SST around New Zealand is warming faster than the 0.28°C/century shown in the de Freitas et al. (2014) paper.
Rebuttal
SST reconstructions are even more fraught with raw data problems than land-based records, especially in the Southern hemisphere. This is well known (Trenberth et al., 1992). There have been numerous attempts to improve this situation, but none have been successful to the point that anyone could state that a reanalysis of NZ land-based temperature records could be right or wrong based on SST reconstructions such as ERSST.
In our paper we draw attention to Folland & Salinger (1995), mentioning the difference, but we would never make the mistake of assuming SST trends are gold-standard records – especially in this part of the world. Indeed, the Hadley Centre (including Dr Folland) has now officially recognised that its previous assumptions regarding pre-WW2 adjustments to ship records have been mistakenly based.
We would also add that NIWA’s 0.9°C/century was as far above F&S (95) as ours was below it, yet NIWA at no stage withdrew their work due to incompatibility with an SST reconstruction.
Views: 185
>”Mullan (2012) is not relevant literature.”
No series. No citation by NIWA. NIWA cite Mullen et al (2010) ‘Report on the Review of NIWA’s ‘Seven-Station’ Temperature Series’ in regard to the 7SS:
https://www.niwa.co.nz/our-science/climate/information-and-resources/nz-temp-record/seven-station-series-temperature-data
But if Mullan (2012) is relevant (supposedly), what was Mullan et all (2010) all about?
Very different approaches. M12 was a response to the revelations of the NZ Climate Science Coalition Statistical Audit of the NIWA 7-Station Review (2011) that showed NIWA’s M10 definitely did not follow RS93. M12 then attempts to “modify” RS93 in ways that, Brett Mullan hopes, justifies M10 – but impossible to do if neither M10 nor M12 follow RS93.
>”From 1949 to 1994, the eleven stations did indeed require no adjustments and, revealingly, showed a temperature rise at the rate of 0.18°C/century.”
But ,,,,,but,,,,,,
[Renowden] – “The fact is that the raw station data from rural sites with long records that require no adjustments show strong warming”
0.18°C/century is “strong” warming?
Amending for update:
>”The 11SS is a very useful corroboration of the 7SS if confined to the 45-year period that the eleven stations all existed. From 1949 to 1994, the eleven stations did indeed require no adjustments and, revealingly, showed a temperature rise at the rate of [0.28°C]/century.”
But ,,,,,but,,,,,,
[Renowden] – “The fact is that the raw station data from rural sites with long records that require no adjustments show strong warming”
[0.28°C]/century is “strong” warming?
>”The 11SS is a very useful corroboration of the 7SS”
>”New Zealand Climate Crisis Gets Worse”
http://quadrant.org.au/opinion/doomed-planet/2010/06/nz-climate-crisis-gets-worse/
Barry Brill:
What NIWA called a 77-year period is in fact a 40-year period, and the graph of that period appears as:
http://quadrant.org.au/wp-content/uploads/2010/06/Brill-2.jpg
The genuine ESS graph has a very different shape from that of the impostor on the NIWA website. It is boring. One can see at a glance that the overall warming/cooling trend is close to zero. In fact, the warming trend rate is 0.28°C per century.
End quote.
As I recall, de Freitas et al (2014) states, approximately, “Our analysis, which uses updated measurement techniques and corrects for shelter-contaminated data, produces a trend of 0.28 °C per century.
Q.E.D.
Barry at Quadrant:
“The selected starting-point of 1931 achieves its exceptionally low reading of -1.32°C from just three stations – Queenstown, Palmerston North and Hamilton”
Hamilton, Ruakura
C75731 2101 Nov 1906 – Feb 1997
C75733 12616 Nov 1996 – Feb 2007 Automation of site
C75734 26117 Dec 2005 – present Small site shift
https://www.niwa.co.nz/our-science/climate/information-and-resources/nz-temp-record/temperature-trends-from-raw-data
Ruakura !!SS anomaly is effectively 2 halves centred at 1970 and flat after 1970.
1970 – 2009: 0.049 C warming @ 0.012 C/decade, 4 decades.
1931 – 1970: 0.532 C warming @ 0.133 C/decade, 4 decades.
Apparently there were no site changes Nov 1906 – Feb 1997. But anyone visiting Ruakura Research Station cannot fail to notice the massive trees and large buildings at the facility. They are not native trees but exotic. The station has been in existence since 1901. Here is a picture ca. 1905:
http://christchurchcitylibraries.com/heritage/photos/disc1/img0092.asp
The trees and buildings I refer to are not there. Here’s the station now:
http://www.agresearch.co.nz/about-us/where-we-are/pics/ruakura.jpg
Big trees and buildings.
CliFlo data for Ruakura 1931 – 1970:
1931 12.5
1932 12.9
1933 13.4
1934 13.3
1935 14.1
1936 12.8
1937 12.6
1938 14.1
1939 12.6
1940 12.2
1941 12.6
1942 13.2
1943 12.8
1944 13.1
1945 12.5
1947 12.7
1948 12.9
1949 12.6
1950 13.1
1951 12.4
1952 12.7
1953 13
1954 13.3
1955 14
1956 14
1957 13.2
1958 13.5
1959 13.1
1960 13.2
1961 13.4
1962 14.1
1963 13.1
1964 13.1
1965 12.8
1966 13.2
1967 13.5
1968 13.3
1969 13.1
1970 14.1
0.56 C warming @ 0.14 C/decade, 4 decades.
Except there were large spikes 1935 (14.1) and 1938 (14.1) which are identical to 1970 (14.1) and typical of 1970 – 2009 at Ruakura. Also typical of the current 7SS regime 2000+.
In other words, there was a cool period between 1938 and 1955, both of which are similar to the present. But was there any effect from the obvious site changes 1931 -1970, trees and buildings?
I think there would have been.
>”But was there any effect from the obvious site changes 1931 -1970, trees and buildings? I think there would have been.”
Maybe not given the 2013/14 photo and map of the NIWA Ruakura site on page 8 pdf here:
http://www.gns.cri.nz/static/pubs/2014/SR%202014-001.pdf
Interesting though was this “Climate records have been collected from this location since 1906”.
Station 2101
1907 13.7
1908 12.8
1909 13.6
1910 13.7
1911 12.6
1912 12.1
1924 14.2
1925 13
1926 13.2
1927 13.5
1928 14.2
1929 13.2
1930 12.4
1931 12.5
Now Station 26117 (same site different instrument – AWS):
2007 14.1
2008 14
2009 13.1
2010 14.3
2011 13.4
2012 12.5
2013 14.8
Are we feeling warmer yet?
Current 30 year average of Ruakura monthly data from NOAA:
http://www.climate-charts.com/Locations/n/NZ9300000C757310.php#data
vs 1907 NIWA CliFlo Ruakura monthly:
18.2, 18.5, 17.3, 14.5, 11.4, 9.3, 8.6, _9.8, 11.4, 13.1, 14.9, 16.8, Mean 13.65 (30 year current average)
17.5, 17.8, 17.7, 15.2, 10.6, 7.9, 9.3, 10.9, 11.6, 12.8, 15.3, 17.8, Mean 13.70 (1907, NIWA)
I’m struggling to see the climate change.
[Renowden/Mullan?] – “Brett Mullan’s 2012 paper [M12] Applying the Rhoades and Salinger Method to New Zealand’s “Seven Stations” Temperature series (Weather & Climate, 32(1), 24-38) deals with the correct application of the methodology described in Rhoades and Salinger’s 1993 paper.”
[Renowden/Mullan?] – “….from 1992 onwards the 7SS was compiled [Mullan et al (2010), M10] using RS93 methods properly applied.”
Self contradictory:
Correlation and weighting comparisons for Masterton 1920, ‘Statistical Audit’ SI vs M10 vs M12:
SI (monthly), M10 (annual), M12 (monthly) correlation comparison
Thorndon
0.73, N/A, 0.79
Albert Park
0.58, N/A, 0.67
Christchurch Gardens
0.68, N/A, 0.97
Taihape
0.88. N/A, 0.78
SI (monthly), M10 (annual), M12 (monthly) weighting comparison
Thorndon
0.24, 0.00, 0.21
Albert Park
0.09, 0.00, 0.11,
Christchurch Gardens
0.18, 0.00, 0.48,
Taihape
0.49, 0.00, 0.20
Maybe the authors would like to speculate why their estimate for NZ warming is so much less than the global average?
First and foremost, the average warming is what it is, formed out of the observations adjusted by the sensible, peer-reviewed mathematics of Rhoades and Salinger. There is no other reason. Second, perhaps you might in turn speculate on why NIWA’s estimate is so much more than the global average?
AIDE MEMOIRE: NIWA: 0.9°C. Global: 0.6°C. dFDB: 0.3°C.
As to what climatology might have been responsible (which I’m sure is the actual focus of your query) you’ll note it wasn’t the purpose of their paper to investigate why the temperatures moved. They set out just to establish what the temperatures were. Still, there is an answer to your query from a very highly placed source. David Wratt actually answered it not too long ago: he said New Zealand temperatures are expected to be mediated by the ocean we’re in, so they will go neither too high nor too low. As that expectation must be based in observation (he being a scientist and everything), it means the ocean has been doing its mediating for quite a while. Hence, we have experienced less warming than the global average.
I hope you ponder why NIWA’s record of the past is 50% higher than the global average, given Dr Wratt’s forecast of moderation. The facts show that our actual temperatures have indeed been moderate, but it seems that not much moderation was in evidence when the ‘official’ NZTR was being adjusted—as we’ve just proved.
Maybe Simon would like to speculate on why NIWA’s measured Hamilton Ruakura 11SS data since 1970 is completely at odds with BEST’s Hamilton warming?
NIWA: 0.049 C/decade 1970 – 2009 (+0.184 C total)
BEST: 0.107 C/decade since 1960 (+0.535 C total)
BEST: 0.213 C/decade since 1990 (+0.426 C total)
Just where did BEST find all that Hamilton warming that NIWA didn’t measure Simon?
Now NZ since 1990,
NIWA: 0.064 C/decade since 1990 (+0.15 C total)
BEST: 0.241 C/decade since 1990 (+0.554 C total)
Again, where did BEST find all that NZ warming that NIWA didn’t measure Simon? That is the era of AWS, bare minimum adjustments, and reference stations, is it not?
Correction:
Hamilton
NIWA: 0.049 C/decade 1970 – 2009 (+0.184 C total)
BEST: 0.107 C/decade since 1960 (+0.567 C total)
BEST: 0.213 C/decade since 1990 (+0.490 C total)
>”….the observations adjusted by the sensible, peer-reviewed mathematics of Rhoades and Salinger. There is no other reason”
That mathematics including UHI/sheltering adjustments, of Hansen.
RC,
“That mathematics including UHI/sheltering adjustments, of Hansen.”
True. No response from Simon just yet. Perhaps he’s taking time for speculation, I mean reflection. 😉
Correction #2
Hamilton
NIWA: 0.012 C/decade 1970 – 2009 (+0.048 C total)
BEST: 0.107 C/decade since 1960 (+0.535 C total)
BEST: 0.213 C/decade since 1990 (+0.426 C total)
I’ll get this right eventually – BEST just gets more wrong (are there degrees of wrong?)
Presumably Sir Peter Gluckman has asked for a please explain from NIWA.