New Zealand’s changing climate and oceans: new Gluckman report out today

The Prime Minister’s science advisor, Sir Peter Gluckman, today released a new report looking at the probable impacts of climate change in New Zealand over the next 40 years. The report, New Zealand’s Changing Climate and Oceans: The impact of human activity
and implications for the future
(pdf) is:

… intended to update the public on current scientific understandings of climate change and ocean acidification. In particular, it focuses on how these changes are likely to affect New Zealand’s climate and industries at a regional level over coming years.

The timing of the report — which appears at first glance to offer a reasonable overview of our current understanding of likely local climate changes — seems a trifle odd. In a matter of months the IPCC will release the first part of its Fifth Report, covering the underlying science, and while we’ll have to wait until March next year for the Working Group 2 report on regional impacts, Gluckman and his team would have had a firmer foundation for their report with only a modest delay.

I’ll be reading the report carefully over the next few days, and will have more to say in due course. I’m particularly interested in exploring how Gluckman approaches the risks associated with local climate changes, and his take on how the wider international context will impact New Zealand.

See also: Peter Griffin, NZ Herald.

39 thoughts on “New Zealand’s changing climate and oceans: new Gluckman report out today”

  1. 0.9 C by 2040?

    That requires 0.33 C/decade starting right now for 13.4 C in 27 yrs time. Given ENSO-neutral NZ temperature has been stuck on the 2012 12.5 C level for about the last 50 yrs that appears highly improbable.

    Maybe the PMs Chief Scientific Adviser should get some better advice than what he was given.

    1. I think that you misread the report here Richard. The Report notes that we already have 0.8 degrees of warming and that this will rise to 0.9 by 2040. That’s 0.033 degrees per decade.

      1. Macro, see Table 1: Summary of projected changes (increases are relative to the 1980-2000 average)

        1980-2000 average is 12.56 C plus 0.9 is 13.46. 2001-2012 average is 12.68 but we are starting from ENSO-neutral 2012 at 12.5 so that’s 0.96 by 2040 starting this year. Actually 0.35 C/decade.

        I take it by your “0.033 degrees per decade” that you also find 0.35 C/decade highly improbable?

      2. My mistake!!

        I think Simon sums it up quite clearly
        I failed to see the note above the table – reading it rather quickly…

        But note also Richard this:

        “To date a rise of 0.8°C in global mean temperature
        has been observed since pre-industrial times, with
        two-thirds of this rise having occurred since 1975.”

        ie The 0.8 degrees of heating already is projected to become around 1.3 – 1.4 degrees above pre-industrial levels (taking the 1/3 of 0.8 off that occurred before 1975 and adding on the 0.9 degrees additional from today – not strictly accurate but a ball park figure).

        Thank you for helping me clear this in my own mind. Using two different means is rather confusing.

        1. The projection and context of the report is for NZ not global Macro.

          Salinger and Mullen (1995) identified a 0.58 C rise NZ-wide 1950 to 1975, those two years being “break points”. Between decades 1941–1950 and 1981–1990 the North Island rise was 0.8°C and 0.7°C for the South Island (according to Salinger and Mullen) but the temperature regime 1975–2012 has been little changed if any. The 1980–2000 average as used by the report as the reference level being typical of the entire period except for ENSO activity.

          The 50 year projection from 1990 (average of 1980–2000) is 0.18 C/decade, only a little less than the 0.23 C/decade over the 25 years 1950 to 1975 which at that time was a substantial climate shift. But as time passes after 1990 and the projected trend isn’t tracked by observations the required trend to reach the 2040 target becomes steeper and steeper and less and less credible, currently some one and a half times greater for 27 years than for the trend of the abrupt shift over the 25 years 1950 to 1975.

          What driver, evidently not active over the last 30 years at least, will suddenly kick in to achieve this Macro? And why does that driver necessarily increase the temperature, not decrease it? And should the possibility of a shift in the opposite direction be excluded from consideration (not mentioned in probabilities) of that driver (whatever it is) in reports such as Gluckman’s? I don’t think so.

          1. Richard also wants us to think that the only indicator of Global Warming is Surface Air Temperatures…. NZ’s Air Temperatures are strongly influenced by the fact that we are an island nation in a large ocean and subject to prevalent westerly winds which moderates both the maximum and minimum air temperatures. He might also like to talk to the people of my town, who at this very point in time are nodding their heads in disbelief at the continuing mild winter the warm sunny days and the warm nights we are presently experiencing. An 80 year old lady of my aquaintance remarked just yesterday how she used to fear the winters because they were so cold. Anecdotal I know – but a person under the age of 28 has never experienced a colder than average year.

          1. Are you implying that the prevailing NZ-wide average temperature at the time of the signing of the Treaty of Waitangi was about 10.9 C Gareth?

            1. No implications. The record is what the record is. What we read it into it — as you demonstrate so vividly — is another matter entirely.

            2. >”The record is what the record is. What we read it into it….”

              Exactly. But a linear trend such as the one on NIWA’a NZT7 (“What we read into it)” is not the most appropriate statistical representation of the record in terms of R-squared values so neither is projection of it in either direction.

              Statistically (for better R2), a better representation is a curve:


              The updates from that graph are 13.1 2010, 12.8 2011 and 12.5 2012. The curve is consistent with Salinger and Mullen’s work, a long cool period (cooler than 1800s), a shift, and a long warm period. Clearly, the 10.9 1840s backwards projected value and 13.4 2040s forwards projected values (Gluckman’s, not the linear trend. 0.98 C/decade gives 12.94 in 2040 – well short of Gluckman and barely above current level) are equally unrealistic.

              A similar linear vs curve comparison of HadCRUT4 over the last 100 yrs provides comparative R-squared values curve vs linear:


              And again, the long-term linear trend is not representative of the signal in the data. Zhen-Shan and Xian (2006) did an EMD analysis (intrinsic signal i.e. NOT “What we read into it” but what the signal actually is) of the China and global record (HadCRUT3) from 1880 – 2000. IMF4 revealed the oscillation as above but the residual (the long-term “trend”) is a decelerating curve reaching zenith in the China record (land only) around 2000 but lagged over a decade due to the oceanic thermal characteristics in HadCRUT3. Both long-term curves (China, HadCRUT4, and I suggest the NZT7) are in change-of-phase, positive-to-negative.

              The only error Zhen-Shan and Xian made was miss-interpretation/miss-attribution (“What we read into it”). The residual trend is almost the exact inverse of the CO2 curve:


            3. Blimey.

              We’ll cut to the chase, shall we? NZ was cooler 120 years ago. We expect it to get warmer as heat accumulates in the climate system. But as Gluckman points out, NZ is also vulnerable to what happens elsewhere. That’s where the immediate climate change impacts are expected and observed.

            4. >”NZ was cooler 120 years ago”

              Didn’t say it wasn’t but you don’t have to go back very far before that to find a much warmer regime than the early 1900s e.g.

              GHCN Dunedin/Auckland composite 1853 – 1863 13.88 °C average.

              The Gluckman report implies 13.46 °C average around 2040 i.e. about the same as mid 1800s.

            5. Rubbish. The raw absolute values from pre-1900 are readily available in NIWA’s CliFlo database or GHCN. and directly comparable to late 1900s/early 2000s raw absolute values from the same databases.

              The latest NIWA NZT7 values (2000s era) are basically raw CliFlo data.

            6. Sorry RC2, but you clearly don’t understand the first thing about homogenised temp series. But then given that you hang out at the home of terminal temperature misunderstanding, I suppose that’s inevitable.

              Please address further comments to the topic of the post, or they will not pass moderation.

            7. Gareth. The example I’ve given has nothing whatsoever to do with contiguous series compilation let alone homogenization methodology. It is simply a comparison of the indicative temperature regimes prevailing in one era compared to another using records of absolute temperature measurement typical of the country (the baseline being 0C or 0K). You do not need a contiguous series spanning 160 years to find the NZ average typical of one 10 year span to compare to another 10 year span 160 years later if both 10 year spans are reasonably typical of the respective eras..

              [Rest snipped – see my warning above.]

            8. Last time: this is nonsense, RC2. The only way you can compare temps on any timescale is if that data is homogenised (= made comparable). If you don’t understand that basic point, or are unwilling to try to understand why that is the case, then I am not going to discuss the issue further. Please restrict your comments to the subject of the post.

            9. Years later, after a disastrous loss at the courts and being told off by the judge, Richard C2 still proves eloquently that that he has learned absolutely nothing whatsoever about the core issue of the subject. Arghh, some souls are just not redeemable.

              He reminds me of those confused tinkerers in their sheds with their perpetual motion inventions, deeply convinced that the “bad conspiracy of science” is suppressing their superior insights… just one more tweak next week and “she’ll will run forever” and the world will come begging for it at the door…. 😉

            10. You could get a R-squared of 1 if your regression had 99 terms.This doesn’t prove anything if your model does not represent the actual underlying processes.
              I can recommend a good introductory statistics book for you: Understanding Statistics – Basic Theory and Practice by Grant Foster. It may help clear up some of your misconceptions.

            11. Yeah well Zhen Shan is a load of crock for a start – well debunked. It looks at Global Cooling from 1940 to 1970 (of which i’m sure you are well aware RC2) and concludes surprise! surprise! Air temperature doesn’t linearly follow CO2!! They conclude “The global climate warming is not solely affected by the CO2 greenhouse effect”. Completely ignoring the aerosol cooling and solar forcing. They compound their errors by failing to recognize that temperatures relationship with CO2 is logarithmic not linear. Not a particularly well regarded piece of research…. but you hang your hat on it RC if it makes you feel more secure.

            12. Your NZT7 “model” suggests that NZ’s air temperature will be 125 degrees Celsius in 2500.
              Please leave climate science to those who know what they are doing.

        2. I provide the graph so that Richard’s comments have some visual context. As the reader will appreciate, NZ being only a small part of the globe, it experiences much greater variability year-to-year than the global average — that is, more ups and downs. That will undoubtedly continue in the future.

          RC2 appears to want to read far too much into the NZ temp record. It is of course very interesting to NZ residents, but it tells us little about the existence or absence of the drivers of global warming – except in that it clearly demonstrates long term and continuing warming in our region that is consistent with the big picture.

          NZ’s climate is determined by the daily, weekly, monthly, seasonal and annual battle between the slow but steady warming-driven southward expansion of the tropics, and the cold continent anchored on the bottom of the planet. The details are determined by the patterns of heat movement in the southern oceans, the effect of diminished (but recovering) ozone over the South Pole, the distribution of sea ice around Antarctica, the behaviour of the Southern Annular Mode, and so on. Complex, variable, and endlessly fascinating.

          There’s no doubt that we face a warming future. We can argue about how much and when, but I don’t particularly want to speculate further until we have a clearer picture of how things play out in the Arctic. How the atmosphere behaves when one pole is warm and the other cold is not something I know a lot about…

    2. Richard C2: “…requires 0.33 C/decade starting right now….”

      You think this is ‘highly improbable’? What is your ‘highly improbable’ in numbers for you? P=0.1, 0.2? whats your take?

      Mind you that on the global record the Atmospheric warming has advanced and leaps and bounds interspersed with sideways or even downwards episodes (Climate Escalator).
      On the back of a prolonged sideways period of atmospheric warming, while Ocean Heat content resembling the vast bulk of the energy imbalance, has risen steadily, what are the odds of the next ratchet movement of atmospheric warming making 0.35 Deg/Centigrade look conservative? Got a take on that?

      1. The BEST trend since 1960 is 0.96°C/century ± 0.27°C.
        The NZT7 series to 2010 is 0.96°C/century ± 0.29°C.
        Two totally different methodologies accounting for weather station differences coincidentally come up with exactly the same answer.
        And to think that the Climate Science Cranks went to the High Court to argue that the NZT7 was invalid. I wonder if they ever paid up?

        1. And since 1990 Simon?

          >”The BEST trend since 1960 is 0.96°C/century ± 0.27°C.
          The NZT7 series [since 1910] to 2010 is 0.96°C/century ± 0.29°C.”

          That is NOT “exactly the same answer” Simon. The BEST trend since 1910 is 0.79°C/century ± 0.21.

          Both NIWA’s and NZCSET’s NZT7s are essentially identical over the second halves of the records (the reference level for Gluckman’s projection). The dispute is over the early period prior to the reference level but even then both series are in the same ball park. BEST is in La La Land, inconsistent with all studies of South Pacific climate e.g.. the 1950 – 1975 period in Salinger and Mullen up-thread and at its silliest at the start of the record in 1840 when apparently Hobart is the proxy for NZ.

          1. Richard C2, the question asked by Simon that I put to your here again was: have you guys paid up to NIWA for the cost that the court awarded against you in the case you brought against NIWA and that the court labeled ‘Prolix’? Or are you hiding your amateurish climate change denial vigilantism still behind the ‘charity’ you erected for the case?

            1. As I understand it, Thomas, discussions are continuing between the NZCSET trustees and NIWA re sheeting home the costs; perhaps Bazza Brill can enlighten us?

            2. I hope the tax payer will not have to carry some of the load in the end through the highly questionable ‘charity’ that the NZCSET was set up to be. Knowing the charity law applicable a bit, I would certainly hope that in the end the directors are personally culpable for causing the loss to their organization through their foolish actions.

        2. Simon, compare 1980 – 2012, BEST vs NIWA.(°C):

          1980 – 2000 (reference period of the Gluckman report)
          12.56 NIWA
          11.30 BEST (by eye)
          1.26 Diff

          2001 – 2012
          12.68 NIWA
          11.50 BEST (by eye)
          1.18 Diff

          BEST just isn’t a credible NZ series when compared to either NIWA’s NZT7 and CliFlo raw data or GHCN for the region over any part of their series.

          It gets bizarre in the 1800s. For example (there are others):

          13.88 GHCN Dunedin/Auckland composite 1853 – 1863
          10.50 BEST NZ output 1853 – 1863
          3.38 Diff

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