Christchurch coastal cock up: sea level “expert” de Lange clueless in NBR

IssacCordalBerlinWillem de Lange, the Waikato University coastal processes lecturer and one of the panellists nominated to review sea level rise advice relied on by Christchurch City Council, helpfully demonstrated the true extent of his climate expertise in the National Business Review last week [WebCite]. In an article titled Evidence doesn’t support rapid future sea level rise, written with Bryan Leyland, de Lange demonstrates just how slapdash his approach to the subject really is.

The piece is riddled with errors and misrepresentations. Here’s a selection:

  • The “recent” paper on sea level rise de Lange and Leyland (dLL) reference in their first paragraph is from 2010! The latest Royal Society of NZ climate info was published last month, and is presumably what dLL meant to refer to.
  • The rise in sea level around NZ over the last 100 years is 17cm, not 14cm, according to the RSNZ (page 28 here).
  • dLL claim that climate models are “flawed”, and have failed to predict current temperatures. In fact current global temperatures are more or less bang in the middle of model projections.
  • In discussing tidal gauge measures of sea level rise they refer to a denialist web site, not the primary sources.
  • They reference a textbook on sea level rise, but neglect to point out that it was published 15 years ago.
  • dLL state that the current rate of sea level rise measured by satellite is 3.2 mm per year, with “indications of recent decline in the rate”. In fact it is 3.4mm per year, and shows no signs of any recent slowdown. If anything, there are hints of an acceleration in the underlying rate.
  • dLL claim that satellite measures are “about twice the tide gauge rate”. They’re not. They’re in good agreement. From Trends and acceleration in global and regional sea levels since 1807, Jevrejeva et al, Global and Planetary Change, 2013 (pdf)
    There is an excellent agreement between the linear trends from GSL12 [latest tide gauge data] and satellite altimetry sea level since 1993, with rates of 3.1 ± 0.6 mm/yr and of 3.2 ± 0.4 mm/yr respectively.
  • The latest RSNZ projections are not “much more than anybody else” – they’re based on the IPCC’s AR5 and draw on the current literature. Larger projected future rises are widely used in planning overseas.
  • dLL state: All the observational evidence indicates that the sea level is likely to rise 0.1 to 0.2 m by 2100.” This appears to be nothing more than wishful thinking. The current SLR rate gives 30cm plus by end of the century as a minimum.
  • There’s strong evidence of increased and increasing ice sheet mass loss in Greenland and Antarctica, which will add significantly to the amount of sea level rise by the end of the century. If we’re lucky, that might only be a metre. If we’re unlucky, it might be a great deal more.

If this were de Lange and Leyland’s only contribution to the debate on how communities should cope with sea level rise, it might be possible to shrug it off as a slapdash attempt at propaganda from a couple of people with a long history of climate denial. But de Lange is getting involved with the Christchurch community’s efforts to deal with this most challenging of issues.

Do Christchurch ratepayers really want to pay for advice from an “expert” who can’t get his facts right, and who is apparently happy to put his name to rubbish? The council should immediately ask for his withdrawal from the panel.

Future sea level rise is a certainty. Dealing with it is going to be challenging for any coastal community. We need a national framework that covers realistic assessments of local risk, and provides a process that allows communities to adapt as equitably as possible as their coastline changes. Trying to ignore or downplay the problem is only going to increase the costs faced by ratepayers and taxpayers in future years. If we allow the process to be contaminated by the input of propagandists we simply set ourselves up for greater losses.

155 thoughts on “Christchurch coastal cock up: sea level “expert” de Lange clueless in NBR”

  1. That Business Review article is terrible, what a shoddy opinion piece. The “poisoning the well” alone should have disqualified it for publication. The text looks like it has been lifted from a Climate Change Denier talking point checklist. Do the authors have any expertise in Climate Change.

  2. >”The rise in sea level around NZ over the last 100 years is 17cm, not 14cm”

    Whatever is is it is that trend is not representative of fkuctuation that saw rates higher in the mid 20th century than in recent decades. This is typical of a number of tide guages globally. Beenstock et al found 65% of long running godd quallity TGs were either flat or falling. Only 35% exhibiting rise skewed the global average.

    NOAA has a 5 yr moving 50 yr trend analysis page. Here’s Auckland and Sydney:

    Variation of 50-Year Mean Sea Level Trends 690-002 Auckland II, New Zealand
    http://tidesandcurrents.noaa.gov/sltrends/global_50yr.htm?stnid=690-002

    Variation of 50-Year Mean Sea Level Trends 680-140 Sydney, Fort Denison 1 & 2, Australia
    http://tidesandcurrents.noaa.gov/sltrends/global_50yr.htm?stnid=680-140

    Recent 50 yr trends are LESS than 1 mm/yr.

    1. >”Beenstock et al found 65% of long running godd quallity TGs were either flat or falling. Only 35% exhibiting rise skewed the global average.”

      TIDE GAUGE LOCATION AND THE MEASUREMENT OF GLOBAL SEA LEVEL RISE
      Beenstock et al (2014)
      http://pluto.mscc.huji.ac.il/~msdfels/wpapers/Tide%20gauge%20location.pdf

      From abstract:

      “We therefore study individual tide gauge data on sea levels from the Permanent Service for Mean Sea Level (PSMSL) during 1807 – 2010 without recourse to data reconstruction. Although mean sea levels are rising by 1mm/year, sea level rise is local rather than global, and is concentrated in the Baltic and Adriatic seas, South East Asia and the Atlantic coast of the United States. In these locations, covering 35 percent of tide gauges, sea levels rose on average by 3.8mm/year. Sea levels were stable in locations covered by 61 percent of tide gauges, and sea levels fell in locations covered by 4 percent of tide gauges. In these locations sea levels fell on average by almost 6mm/year”

      1. Where precisely, journal-wise was that ‘paper’ published, Dixie? Why do you suppose the lead author and the third and fourth authors are, it seems, economists? What would you say the fact that it’s apparently been cited 4 times, according to Google Scholar, means?

        Reading those citation links is also, um, enlightening…

        1. Don’t worry bill – you will start a flood of gobbledegook and tosh the like of which you will have never seen before!
          Welcome back. 🙂

          1. Ta Macro!

            This just seems rather a, um, slender reed to be basing decisions that have real-world impacts on, particularly given the sheer weight of counter-expertise.

            And I certainly recall the (submarine) mountain of bafflegab that can be generated surrounding magical undersea volcanoes, for example…

            1. Ooops! Seem to have left a nebulous comment there!
              But completely off topic we were treated last night to an excellent talk by the Godfather of Coral Prof Charlie Veron. If you haven’t already heard him bill – I’m sure you will appreciate this. I don’t say enjoy – how does one enjoy hearing of the destruction of 20% of the GBR. 🙁

      2. Gee, Dixie, you’ve apparently returned but not answered my questions. I’m disappointed.

        My further question: no-one would have put this paper up to the sea-level panel being discussed, would they? I’d be, um, intrigued to see what they made of it.

  3. A sample of NZ TG data

    TAURANGA (SALISBURY WHARF)
    http://www.psmsl.org/data/obtaining/stations/1590.php

    PORT TARANAKI
    http://www.psmsl.org/data/obtaining/stations/996.php

    PORT CHALMERS
    http://www.psmsl.org/data/obtaining/stations/1643.php

    WESTPORT HARBOUR
    http://www.psmsl.org/data/obtaining/stations/1004.php

    From PSMSL: Obtaining Tide Gauge Data
    http://www.psmsl.org/data/obtaining/

    The IPCC’s SLR baseline is the average of 1980 – 1999 centred on 1990 i.e. their projections, as should any from MfE, GNS, NIWA, whoever, begin at 1990. But it is impossible to reconcile “global” projections with the local data above which certainly does NOT exhibit any “acceleration” from 1990.

  4. Pacific satellite SL paper:

    ‘Is anthropogenic sea level fingerprint already detectable in the Pacific Ocean?’
    Palanisamy et al (2015)
    http://iopscience.iop.org/article/10.1088/1748-9326/10/8/084024/pdf

    Vast areas of sea level FALL in the Pacific (see Fig 1). The finding was “NO”, an anthropogenic sea level fingerprint is NOT already detectable in the Pacific Ocean and that we would have to wait “decades” if it were ever to emerge from natural variation.

    In other words, Pacific SLR is a non-issue but may become topical again in around 30 years time if the IPCC speculation is revisited – if anyone is still interested then.

    And what you are effectively looking at in Pacific satellite sea leval (see Palanisamy et al Fig 1) is Indo-Pacific Warm Pool (IPWP) skew. There is NO typical satellite SLR rate in the Pacific. How can there be when much of Pacific satellite sea leavels are FALLING, and in some areas at a statistically significant of MORE THAN -4 mm/yr?

  5. RichardC: Please do not spam this discussion with meaningless linkage. Make an argument, and support it with references to the literature, or I will have no alternative but to put you in moderation. Remember, brevity and clarity are a virtue.

  6. If anybody wants to read De Lange’s own words on climate change, here is a sample:

    http://www.climaterealists.org.nz/node/150

    And what a complete load of tosh indeed!!!

    De Lange implies that the observed increase of the CO2 concentration in the atmosphere is caused by rising ocean temperatures and the outgassing of CO2 from the oceans and not from fossil fuel burning….

    He seems to be totally unaware of the fact that the oceans are currently a carbon sink and the ocean’s dissolved CO2 is actually measured and is increasing in accord with our fossil fuel emissions and with the also observed decrease of the pH level that goes hand in hand with that. His statement that: “there is a contribution (to the atmospheric CO2 increase) from the burning of fossil fuels, it is of the order 1-5 percent of the increase.” is simply baffling, especially as he provides this statement with not an iota of evidence or reference to support such claim. (because of cause there is none whatsoever)

    If he thinks he can afford an opinion on climate change, would one not at least assume that he reads the literature?

    1. You have the opportunity to intervene and write to Christchurch City Council on why they are being misled, Thomas.

      Once you are in the “system” though, it is hard to leave, let me warn you

    2. It’s a bit dated. But yes, his conclusions read like they have been taken from a climate change denier talking point list.

      I see this often.

    3. I burst out laughing when I read this:
      The inconvenient truth that is generally ignored, is that the atmosphere is not capable of warming the oceans to any significant degree – 99.9 percent of ocean heat is derived from sunlight at wavelengths less than 3 microns. The balance is mostly from heat leaking from the interior of the Earth.
      This is probably where Treadgold gets his crank ideas from. How can an export on coastal oceanography be unaware of the existence of gyres, thermohaline circulation, and Ekman transport? I wonder how he explains the effect of ENSO on surface temperature.

      1. Who is Treadgold?

        The atmosphere does indeed warm the ocean. I am not even a scientist and I know that. There was a myth circulating several years ago which claims that back-scattered infra red radiation cannot be absorbed by the ocean.

        Easy enough to refute. Greenhouse gases in the atmosphere raise the global mean temperature by around 33C. If none of this worked it’s way into the oceans, they would be frozen to the bottom.

        Kindergarten stuff…

        1. Harry, suggest you defer to research of optical obsorption of water from which we have safe and successful laser eye surgery for example:

          Optical Absorption of Water Compendium
          http://omlc.org/spectra/water/abs/index.html

          This for starters – “The data is surprisingly consistent. Plot a couple for yourself, or you can just look at (Segelstein) or (Hale and Querry) or (Wieliczka).”

          Effective LW penetration is about 10 microns, max about 100. 100 microns is about the thickness of a human hair.

          Then there’s the earth’s surface energy budget as cited in IPCC AR5 Chapter 2:

          Stephens et al (2012) Fig 1
          http://www.nature.com/ngeo/journal/v5/n10/fig_tab/ngeo1580_F1.html

          Net LW COOLING flux at the surface of 53 W.m-2 (398 – 345).

          BTW, for the space race the US Airforce Labs modelled the temperature profile of the atmosphere from surface to top (validated too) without recourse to radiative effects and neglecting CO2 as an insignificant trace gas, which as a component of the 345 W.m-2 DLR in Fig 1 above was 6 W.m-2 in the US Standard Atmosphere 1976. Since then the change has been in tenths of a Watt per decade.

          1. richardcfromnz.

            I cannot understand what you are talking about – throwing links and cut n’ pastes around without a supporting narrative is unhelpful and lazy.

            “Effective LW penetration is about 10 microns, max about 100. 100 microns is about the thickness of a human hair.”

            Here you do seem to be agreeing with me, you say LW is absorbed by the ocean skin.

            You do not respond to my point about greenhouse gases raising the global temperature around 33C.

          2. Earth’s surface area = 510 million square kilometres. That is 510,000,000,000,000 square metres with an energy imbalance of around 1 W per square metre (your figures). That is 510,000,000,000,000 Joules per second. Now tell me the planet isn’t warming.

      2. Simon

        >”How can an export on coastal oceanography be unaware of the existence of gyres, thermohaline circulation, and Ekman transport? I wonder how he explains the effect of ENSO on surface temperature.”

        He probably does but you seem to be implying that those processess are somehow an oceanic absorption of atmospheric energy (correct me if I’ve got you wrong). The energy transfers are in the opposite direction, see the surface energy budget as cited in IPCC AR5 Chapter 2:

        Stephens et al (2012) Fig 1
        http://www.nature.com/ngeo/journal/v5/n10/fig_tab/ngeo1580_F1.html

        The only transfers into the ocean are SW down and LW down. Transfers out (up) are SW, SH, LH, and LW. Net LW is 53 W.m-2 (398 – 345) out (up).

        That leaves solar SW the only transfer in (down) to heat the ocean.

        1. Radiation is but one mechanism of energy transfer. See also: conduction, convection, absorption. de Lange must surely know this, it’s a cynical red herring that only catch out those who lack basic understanding or critical faculties.

          1. Simon

            >”Radiation is but one mechanism of energy transfer. See also: conduction, convection, absorption. de Lange must surely know this,…”

            I think every oceanographer, including de Lange, knows that Simon. See these definitive papers for exmple:

            Cool-skin and warm-layer effects on sea surface temperature’ C. W. Fairall, E. F. Bradley, J. S. Godfrey, G. A. Wick, J. B. Edson, G. S. Young (1996)
            ftp://ftp.etl.noaa.gov/users/cfairall/wcrp_wgsf/computer_programs/cor3_0/95JC03190.pdf

            ‘The upper ocean heat balance in the western equatorial Pacific warm pool during September-December 1992′ Cronin and McPhaden (1997)
            http://www.pmel.noaa.gov/pubs/outstand/cron1713/

            But you’ve just identified what I’ve stated (almost), which was:

            [Snipped: Far too long – and a word salad. Please, as I have asked you before, keep your comments concise and clear. GR]

    4. So De Lange claims global warming is CO2 being released from the oceans. Surely the oceans are absorbing CO2, given they are acidifying? Can we have De Lange removed from this panel on the basis of mental incompetence?

      Come on Mr Thomas, you clearly know your stuff. If you have time, make a submission. Don’t let Andy scare you off with his empty scaremongering. The worst they can do is send you emails and want clarifications.

      Sea levels are not rising evenly around the world. This could be partly geological uplift and subsidence and rebounding effects etc. This is not much comfort for places where sea levels are indeed rising, and this can only be due to melting ice sheets and warming oceans.

      There is also no guarantee that recent regional differences will continue in the same ways, as all the related geological processes are dynamic, and regions may also be overwhelmed by a general acceleration in sea level rise. Regional differences are important, but the global average is the most important thing. Some people cant see the wood for the trees (I suspect deliberately so at times).

      1. In a way, it will be interesting what De Lange will have to say to the rest of the panel. Somebody who makes crazy statements like he will soon find himself deeply stuck in gaga land. And perhaps this will serve as a deterrent to others who might try to prevent SLR from being taken seriously. I wonder what De Lange would have to say for example if cross-examined on his hilarious statements on GHG and ocean temperatures (see above). I am not so sure that those who like an expert to help them with a fight against SLR policy will enjoy that ‘expert’ they conjured up for their cause…. 😉

    1. This isn’t true, not a word of it is true.

      Since I was in the Community Reference Group and you weren’t, I can say that with some confidence

      Maybe you would like to temper your comment with a prelude, such as “in my opinion…”.
      There was one member of the group who has a PhD in Paleoclimate, for example. There were no landlords represented in the group.

      1. So Andy says landlords didnt push for the people on the panel.

        But in a previous post Andy was very reluctant to say who did push for these particular people, particularly the sceptics on the panel. He was very reluctant to state who he pushed for. He said it was none of anyones business.

        Andy is not one for transparency or openness. He expects everyone to just take him at his word, without having to be explicit or offer any evidence. Ha ha. Not good enough.

        1. “He expects everyone to just take him at his word, without having to be explicit or offer any evidence. Ha ha. Not good enough.”

          No, not good enough. I suggest you contact GHD via the email address given on this website

          http://www.christchurchsealevelrise.co.nz/

          I’m sure they will be happy to provide you with meeting minutes. I’ve got nothing to hide

            1. Yes I personally recommended Dave Frame and Kesten Green

              Green is off the panel, by the way

      1. “Murray is a statistician and scientist with a strong background in probability, forecasting and mathematical statistics. Broad experience as a university lecturer, statistical researcher, consultant and collaborator with scientists in engineering, marine science, atmospherics physics. Murray has collaborated with engineers in problems relating to reliability, design of experiments, traffic, pipe, infrastructure and automotive engineering. More recently Murray worked with atmospheric physicists at NIWA to develop statistical methods to estimate methane production and computational methods for Markov chain Monte Carlo techniques. Murray has worked as a Senior Scientist at NIWA from 2002 – 2011, prior to this he was a senior lecturer in Engineering Statistics at the University of Auckland.”

          1. This was the latest email sent out today from GHD to all registered subscribers
            >>>>
            The Peer Review Panel has now been appointed and have made a start on the Peer Review of the Coastal Hazard Assessment Report (Tonkin & Taylor Ltd 2015).

            After a process of negotiating with the short listed candidates on contract terms, commercial arrangements, availability and assessing timeframes for delivery, the peer review panel members have now been appointed and are underway.

            This has resulted in the inclusion of Dr Murray Smith who was not on the original panel list presented to Council. His inclusion and the panel itself has been finalised in collaboration with the Community Reference Group that was established to inform the terms of reference and membership of the panel.

            The Peer Review Panel includes the following experts:
            1. Legal expert and chair: Shonagh Kenderdine

            2. Regional science expert: Dr Deidre Hart

            3. National science expert: Dr Willem De Lange

            4. International science expert Associate Professor: Ron Cox

            5. Statistician: Dr Murray Smith

            The estimated delivery date of the final report is August 2016.

            Thank you to the members of the Community Reference Group who spent a number of long evenings together to work through the terms of reference and short list of panel members.

            Please visit the website for more updates: http://www.christchurchsealevelrise.co.nz/
            Further changes to the website will go live tonight.

            Your next update has been programmed towards the end of July after the Community Reference Group has met to discuss initial findings from the peer review panel.

            Kind Regards

            Maurice Hoban
            GHD Limited

  7. I protest the lack of balance on this panel!

    Sure, there’s de Lange, as a token pseudoscientist, but where’s Ken Ring?

    Hell, there’s not even a homeopath or an anti-vaxxer…

    WAKE UP, SHEEPLE!!

  8. The Jevrejeva et al, Global and Planetary Change, 2013 paper that you cite to support the assertion that tide gauge and satellite data are in sync seems a little ambiguous on several fronts.

    In particular, the acceleration reported in SLR is very sensitive to start and end points.

  9. Re Jevrejeva et al, Global and Planetary Change, 2013

    TG data in Figure 14 and Table 1 of Jevrejeva et al (2013) make a mockery of their “acceleration” claims. Compare the swpacific graph (rise) to sepacific (flat) in Fig 1 for example.

    Similarly Table 1: Linear trends for 14 regions since 1970 [1970–2008]

    Basin, Trend (mm·yr−1)
    Antarctic 4.1 ±0.8
    Arctic 3.6 ±0.3
    Balticb 1.7 ±0.6
    Cpacific 2.2 ±1.4
    Indian −0.1 ±1.3
    Mediterr 2.7 ±0.5
    Neatlantic 0.9 ±0.6
    Nepacific −0.7 ±0.3
    Nwatlantic 1.6 ±0.3
    Nwpacific 2.7 ±0.6
    Seatlantic N/A [rise – see Fig 1 graph]
    Sepacific N/A [flat – see Fig 1 graph]
    Swatlantic 1.0 ±0.8
    Swpacific 1.3 ±0.6

    There’s no way they can claim “an acceleration of 0.02 ± 0.01 mm·yr−2 in global sea level (1807–2009)” from that lot. Especially given the Indian rate (−0.1 ±1.3 mm/yr). The Indian is a major ocean basin where rising ocean heat content overwhelms the entire global OHC metric but basin SL is flat.

    Then they have the contradictory problem (except Nepacific −0.7 mm/yr in Table 1) of all the satellite measured Pacific sea level FALL (blue areas but at rates much greater than −0.7 Nepacific) in Fig 1a of this paper:

    ‘Is anthropogenic sea level fingerprint already detectable in the Pacific Ocean?’
    Palanisamy et al (2015)
    http://iopscience.iop.org/article/10.1088/1748-9326/10/8/084024/pdf

    Also, Jevrejeva et al is not an attribution paper. They are explicitly equivocal on that in 4. Discussion, page 10 pdf:

    “It is debatable whether acceleration of sea level rise in the 20th century is due to anthropogenic climate change.”

    When data prior to 1880 determines the greater acceleration (from paper and see Andy’s comment above), anthropogenic cause is immediately ruled out. This is corroborated by attribution papers, aforementioned Palanisamy et al (2015) in particular, that find no human “fingerprint” in satellite era Pacific sea level data at least. 19th century TG data is not the missing clincher.

  10. >”The rise in sea level around NZ over the last 100 years is 17cm, not 14cm, according to the RSNZ”

    OK 1.7 mm/yr 1915 to 2015 (1,4 in the 20th century). But an average that does not apply anwhere around NZ or the SW Pacific (mm/yr):

    Townsville 1.48
    Bundaberg 0.58
    Brisbane 0.09
    Sydney 0.65
    Auckland 1.29
    Wellington 2.45
    Lyttleton 2.36
    Bluff 1.57

    From http://tidesandcurrents.noaa.gov/sltrends/southeastwestpacifictrends.htm

    The SW Pacific average works out to 1.3 mm/yr but of what relevance anywhere? Only Auckland conforms, but neither Auckland nor the SW Pacific average conforms to the RSNZ NZ average.

    TG or satellite SL averages are an illusion; non-existent except by sheer chance somewhere e.g. Auckland and SW Pacific.

  11. “The “recent” paper on sea level rise de Lange and Leyland (dLL) reference in their first paragraph is from 2010! ”
    – Hair splitting – six years?

    “The rise in sea level around NZ over the last 100 years is 17cm, not 14cm, according to the RSNZ (page 28 here).”
    – Hair splitting – 3cm?

    “dLL claim that climate models are “flawed”, and have failed to predict current temperatures. In fact current global temperatures are more or less bang in the middle of model projections.”
    – Whatever – it’s models, enough said.

    “In discussing tidal gauge measures of sea level rise they refer to a denialist web site, not the primary sources.”
    – So is the logic wrong because you don’t like the link?

    “They reference a textbook on sea level rise, but neglect to point out that it was published 15 years ago.”
    – So what?

    “dLL state that the current rate of sea level rise measured by satellite is 3.2 mm per year, with “indications of recent decline in the rate”. In fact it is 3.4mm per year”
    – Hair splitting – 0.2mm?

    “dLL claim that satellite measures are “about twice the tide gauge rate”. They’re not. They’re in good agreement. From Trends and acceleration in global and regional sea levels since 1807, Jevrejeva et al, Global and Planetary Change, 2013 (pdf)”
    – Link broken, so cannot verify your contention.

    “dLL state: “All the observational evidence indicates that the sea level is likely to rise 0.1 to 0.2 m by 2100.” This appears to be nothing more than wishful thinking.”
    – Not wishful thinking, based on “observational evidence”.

    “There’s strong evidence of increased and increasing ice sheet mass loss in Greenland and Antarctica,”
    – Evidence of increasing ice sheet mass in Antarctica: http://www.nasa.gov/feature/goddard/nasa-study-mass-gains-of-antarctic-ice-sheet-greater-than-losses

    1. Sorry Mike, let’s try this again:

      – over the past six years, a lot of new evidence has been produced that adds to the concerns on SLR, which dLL completely ignore. Not referring to the current state of our understanding is under the circumstances very misleading.
      http://www.scientificamerican.com/article/new-data-reveal-stunning-acceleration-of-sea-level-rise/

      – wrong facts of SLR observations in sLL is not hear splitting. dLL try to argue with our current best predictions of SLR this century, they better start with having their facts right.

      – it is false logic to dismiss the predictions of climate models, especially if these are producing a remarkably close match to our observations. Models and their predictions are an essential part of all forecasting methods.

      – denialist websites are not reliable evidence for climate forecasting. If they are working towards informing policy decisions dLL should refer to peer-reviewed published best practice science.

      – again, scientific evidence informing SLR predictions has evolved significantly over the last decade and a 15-year-old textbook is simply no longer reliable.

      – the difference of 3.2 to 3.4 is over 6%. When you are trying to predict SLR developments along an accelerating trend, a 6% error in reporting you data will result in significant differences along the line…

      – Broken link? Tried to google the reference perhaps: “Jevrejeva et al, Global and Planetary Change, 2013 (pdf)”. You get to the source in seconds yourself:
      http://kaares.ulapland.fi/home/hkunta/jmoore/pdfs/Jevrejevaetal2013GPChange.pdf

      – dLL’s infantile linear projection of an under-reported average SLR trend over the last century is complete nonsense. It is equally ludicrous as a linear projection of money accumulating with compounding interest!
      The observations clearly show an accelerating global SLR trend and the non-linear components due to accelerating ice loss will become significant in the remainder of the century.

      – The NASA article you cited says, 6th paragraph:

      But it might only take a few decades for Antarctica’s growth to reverse, according to Zwally. “If the losses of the Antarctic Peninsula and parts of West Antarctica continue to increase at the same rate they’ve been increasing for the last two decades, the losses will catch up with the long-term gain in East Antarctica in 20 or 30 years — I don’t think there will be enough snowfall increase to offset these losses.”

      At which state the SLR rate will continue to increase significantly as the current compensating effect falls away. Did you even read the article – or as most deniers do – simply gawk at the headline?

      1. Thomas, in your Scientific American article on the “stunning” level of sea level rise doesn’t actually give any data on this “stunning” acceleration

        Obviously, if the coastal residents of NZ need to be warned of “stunning” levels of sea level rise, then some indication of actual numbers might be helpful.

        Clearly, Scientific American isn’t actually a reputable science journal and can get away with this kind of stuff.

        1. What are you on about Andy? The very first table in the scientific american article has specific ” data” on increases in coastal flood days in America, and shows some form of exponential increase over the last 100 years. I would certainly say thats very significant.

          I dont know what the data is for NZ, but we are clearly at least at risk going forwards. I will leave it to the experts to figure out how much, until someone shows in very specific detail why they might be wrong, and you consistently fail to do this.

          NZ is not immune to global changes. NZ is generally at risk of accelerated sea level rise over coming decades. Increasing global temperatures will logically increase ice loss and thermal expansion etc and feedback effects, and NZ will not be immune. Why would we be immune? Theres no reason.

          1. What are you on about Andy?

            The article claims an increase in coastal flooding, but makes no claim about sea level rise as its cause.

            In NZ, sea level rise has been linear in nature for the last 100 years.

            This is not a stunning acceleration. It is no acceleration at all.

            1. Why do you use a period of 100 years when you are trying to determine whether sea level acceleration is occurring, but restrict yourself to 17, 18, 19 years when determining temperature increases? It looks as if are actively not trying to find what you are supposedly looking for.

            2. Ghosh Andy, here paragraph 2 from the SA article:

              The new study, the culmination of a decade of work by three teams of farflung scientists, has charted what they called an “acceleration” in sea level rise that’s triggering and worsening flooding in coastlines around the world.

              You need some new spectacles or perhaps a reader / writer to assist you with disseminating written language and to prevent you from making a pile of blunders when the fingers hit the keyboard. Your mental disconnect is evidently getting worse.
              Perhaps time to see a specialist….

            3. AndyS

              The Scientific American article is quite explicit that accelerating sea levels and climate change are causing more flood events in America. Granted the article is about america.

              NZ has indeed had a linear rate of sea level rise for the last 100 years and of about 2mm on average. However NZ data is not great in coverage or extent, and there may be a hidden acceleration.

              In comparison the planet has had sea level rise of about 2.5mm on average over the last 100 years. The rate in the 1920s was about 1.8mm and since 1970 it has climbed to about 3mm year.

              I would suggest NZ has experienced a lower rate of sea level rise to the planetary average due to geologic uplift. What else could it be? I’m genuinely interested if anyone knows.

              Geological factors may have masked any acceleration.

              The point is you CANNOT assume the linear trend of 2mm year for NZ will just continue. The IPCC has categorically stated that sea level rise will accelerate globally, and significantly from about 2040, and this must impact on NZ, and lift the rate of sea level rise given any geological factors are likely to be constant over extended timeframes. We may not experience the same rate as the global average, but it will be higher than currently.

              NIWA have calculated NZ is on track for substantial sea level rise by the end of the century from about 400 – 1000 mm (depending on emissions scenarios) and would have considered regional factors like land subsidence and uplift. Of course rates will vary around NZ, and these are averages.

        2. Andy: Scientific American sums up research in an easily accessible manner. And the focus on coastal flooding days is rather relevant to our discussion don’t you think?
          If you just bothered to read the article, it links directly to the publication of the relevant paper. To save you the “bother” of clicking on it yourself, here it is:
          http://www.pnas.org/content/113/11/E1434.full
          And look, it’s not even behind a paywall…
          You try to hard to avoid seeing what is plainly in front of you Andy when the evidence is not supporting your cognitive bias. It’s rather funny to watch you struggle in front of an audience to try to hide the facts. 🙂

          Plus if you just wanted to look a bit further, how about this Nature article here:
          http://www.nature.com/news/antarctic-model-raises-prospect-of-unstoppable-ice-collapse-1.19638
          (March 2016), which certainly dLL will want to ignore in their “deliberations” on the matter.

          And once again Andy, just plotting a linear forecast from last centuries “average” SLR is just plain silly of you. When the average global SLR is 1m, NZ will not be immune from that.

          1. Thanks for the link Thomas. It it happens, I did already “bother” to read it.

            As you can see, the paper refers to a paleoclimate reconstruction of sea level rise that has been spliced onto instrumental data for the 20th C to create a “hockey stick” effect.

            This is indeed “stunning” in a number of ways, but it does not reflect the fact that there is no acceleration in the instrumental record at most tide gauge stations, including all of NZ.

            Whilst the experts all agree that sea levels will accelerate at some point in the future, this is as yet not apparent in the tide gauge data. Church and White papers suggest an acceleration in SLR but even this would only add a few cm over the current linear trend, according to my calculations, which I am happy to share with you if you can be ‘bothered”.

            1. Sorry Andy, you keep repeating the same denial – or shall we say lies.

              https://upload.wikimedia.org/wikipedia/commons/6/65/Trends_in_global_average_absolute_sea_level%2C_1880-2013.png

              Check the development of the gradient of the global SLR curve yourself. You will agree that the second derivative is clearly positive, especially also in the last decade in the tide gauges. As has been explained to you, NZ’s gradual geological processes may mask some of the SLR seen in other places of the world, but the projections for the acceleration of SLR over this century clearly indicated that NZ geological process and their speed will be no match to compensate for the coming SLR rates.

              https://www.theguardian.com/environment/climate-consensus-97-per-cent/2016/mar/11/sea-level-rise-is-accelerating-how-much-it-costs-is-up-to-us

            2. Hi Thomas
              Thanks for your link to The Guardian,
              When accusing me of lying, perhaps you would like to review the previous comments I made in this thread in which I cited the Church and White papers which do acknowledge a small but significant acceleration in sea level rise, as yet not manifested in most tidal gauges

              So please, when accusing me of lying, bear in mind I have read and cited the papers in this area, and you have cited The Guardian

            3. As you state that you read all the papers, my comment that you are lying (not just being ignorant) seems appropriate:

              Whilst the experts all agree that sea levels will accelerate at some point in the future, this is as yet not apparent in the tide gauge data.

              You will then be well aware that the average SLR since 1870 was about 1.7mm/y and the average SLR over the last 20 years has accelerated to almost twice this at 3.2 mm/y.

            4. Thomas writes:

              You will then be well aware that the average SLR since 1870 was about 1.7mm/y and the average SLR over the last 20 years has accelerated to almost twice this at 3.2 mm/y.

              I am aware that the tidal gauge data in NZ is and has been around 1.7mm a year for the last century. I am also aware that the satellite data shows 3.2mm a year for the last 20 years, and no one quite knows why the two are different.

            5. AndyS,

              You ask why is the tidal gauge data for NZ 1.8mm for the least 20 years while the satellite data is 3.2mm?

              Firstly I suggest you have a look at the following article, which has a sea level rise graph for NZ. This includes both historical data for both tidal gauges and satellites, and also future projections. Its a good graph as it overlays things.

              http://www.mfe.govt.nz/publications/climate-change/preparing-coastal-change-guide-local-government-new-zealand/part-one

              The tidal gauge data for the last 20 years roughly is not 1.8 mm. From that graph it is obviously steeper for this specific time period and looks closer to the satellite data of 3.2 mm. There’s no big discrepancy between tidal and satellite data.

              Just in general terms the way I read the graph if you eyeball the graph for NZ is the overall 100 year trend is linear rather than a concave curve, but theres clearly an acceleration over the last 20 years in both tidal and satellite data. Granted its only 20 years so is sort of on the borderline of statistical certainty. But its an ominous sign surely, and does fit with expectations of an acceleration.

              To me the historical record is not the defining thing. What counts is projections going forward, and the evidence form the IPCC suggests globally accelerating sea level rise would hugely overwhelm the existing trends in NZ of 1.8mm per century. This is apparent in the graph.

              As I suspected geologic uplift is an important factor in NZ and is 0.5mm per year. You will also note from the article that tidal gauge data is relative and when you adjust for uplift, absolute sea level rise in NZ is actually more than the global average over the last 100 years. I’m not sure why.

            6. Andy, yes I acknowledge that study only finds an acceleration in Wellington.

              However the study is 2011, while the information in my link is dated this year, so the study you quoted is getting a bit dated.

              Currently eye balling the graph in my link theres just a recent upswing of about 15 years or so. We would need a good 25 years upswing or acceleration over NZ as a whole to say with certainty any acceleration is more than just internal noise. Same issue as the pause. However we can be about 70% certain things are accelerating, in my opinion.

              The real point is tidal gauges and satellite data is not in conflict, as is obvious in the article, and what counts is what the models say about the future.

              Basically everyone is saying sea level rise will accelerate in NZ and we are heading towards problems. If we have any sense we will take middle level IPCC estimates at the very least. Remember anything the IPCC says is conservative. There is plenty of science saying sea level rise could be over one metre by the end of the century.

              There are at least two important drivers of global sea levels, arctic temperatures, rates of arctic ice loss, and ice sheet destabilisation in the Antarctic. All these are running ahead of past IPCC estimates. There is no way NZ can escape the impact of this.

            7. Andy the issue is NOT about NZ and its current millimeter counting due to our geological situation. The issue for all of us including NZ is the global SLR. There is no fudging it, SLR globally has accelerated AND in fact, the tidal gauges lately show a more rapid rise than the satellite data. At a projected 1m SLR globally there is NO way that NZ’s geology or slow uplift will provide much protection from this. And going forward, we have now created a situation that will make several meters of global SLR pretty much inevitable. Your nit picking about millimeters and your clinging to the idea that we should project a low linear rise rate for NZ going forward is just plain silly and would be irresponsible as a basis for policy development.

              Just look at the graph again, any comments about satellite data being excessive compared to tide gauges are plain wrong on a global perspective and the acceleration of the trend is obvious to all.
              https://upload.wikimedia.org/wikipedia/commons/6/65/Trends_in_global_average_absolute_sea_level%2C_1880-2013.png

            8. I agree global sea level rise over the last 100 years is a smooth slightly accelerating continuous curve. There is certainly no sign of it slowing down.

              NZ’s trend is more of a roller coaster. The graph shows a steep rise early part of last century, then a fall off and now its becoming steeper again. The trend through this is linear on the whole, but its more important to ask why NZs graph is such a roller coaster compared to the global graph. Its likely to be geological conditions perhaps varying over quite short time frames, or some other local event to cause a steep rise early last century. This may all effectively be masking an underlying acceleration over the full 100 year period.

              However the long term geological uplift in NZ is 0.5mm year, so obviously the future ‘projected’ global sea level rise of above 3.2mm a year would totally overwhelm any geological factors in NZ. The net result is the expected further global acceleration in sea level rise from increasing temperatures must impact strongly on NZ.

            9. Nigel states

              However the long term geological uplift in NZ is 0.5mm year, so obviously the future ‘projected’ global sea level rise of above 3.2mm a year would totally overwhelm any geological factors in NZ.

              Uplift in NZ is largely around the Alpine Fault which is over 5mm a year. In the Canterbury plains, the land is subsiding, but this is offset by accretion due to sediment being washed down from the Alps by the large braided rivers such as the Waimak, Rakaia and Rangitata
              http://www.teara.govt.nz/en/map/8406/uplift-of-new-zealand

            10. Andy, sedimentation accretion won’t save the land that is already built on. Once subsidence AND/OR SLR has converted what is dry land today into an estuarine environment, then perhaps gravel from the alps will be deposited there to slow the rate of further flooding…. but unless you are already living inside the riverbed, this process won’t deliver a pebble to your patch and obviously won’t make one iota of difference to your land.

            11. AndyS

              You say most of the uplift around NZ relates to the alpine fault and is 5mm year. Ok so this suggests the west coast of the south island may experience low rates of sea level rise, well not many people live there anyway.

              You say Canterbury is subsiding but this is offset by sediment accretion. I agree with Thomas on the extent of area this affects, so it doesn’t offer much comfort. However you don’t explain whether sediment exactly offsets land subsidence. Assuming it does, the whole area is still therefore susceptible to even slightly accelerated sea level rise in coming decades.

              This leaves the rest of NZ which from your post has 0.5mm of land uplift or less. This includes major population centres in the north island. Again such a low level of uplift and the current 2mm year sea level rise (as a 100 year average) will be overwhelmed by even a slight global acceleration.

              Basically the average uplift for NZ is 0.5mm but obviously it varies, so coastal policy will have to reflect this. The people planning sea level rise defences or policy are not idiots, and the very first thing they will consider is local geology and other local influences. Not an easy job I have to say.

        1. OMG! a link to the Church of the Cooling World….
          You know Mike, last month was the 14th consecutive month when the world’s average temperature exceeded all other records for that month since 1880?
          If you want to participate in discussion here – please link to Articles backed by peer reviewed science, or preferably to the original journal itself, to justify your position. Repeating tripe from denialist blogs does not cut the mustard.
          Just to show you that peer reviewed science does indeed confirm that Climate Models correctly predict the resulting temperature and SLR outcomes within the standard error range, here is a paper published in Naturein 2014.
          To quote the abstract

          The question of how climate model projections have tracked the actual evolution of global mean surface air temperature is important in establishing the credibility of their projections. Some studies and the IPCC Fifth Assessment Report suggest that the recent 15-year period (1998–2012) provides evidence that models are overestimating current temperature evolution. Such comparisons are not evidence against model trends because they represent only one realization where the decadal natural variability component of the model climate is generally not in phase with observations. We present a more appropriate test of models where only those models with natural variability (represented by El Niño/Southern Oscillation) largely in phase with observations are selected from multi-model ensembles for comparison with observations. These tests show that climate models have provided good estimates of 15-year trends, including for recent periods and for Pacific spatial trend patterns.

          .

        2. I can argue at some length about what the climate model projections mean, but it would be boring. When it comes to climate science it is important to not rely on any one estimated temperature data set, or even on one particular type of climate model.

          This is the latest from Gavin Schmidt. It is not a “study” as such but I am happy to accept it as Gavin Schmidt has a good reputation. TL;DR the observations are a good match with this particular set of climate model projections.

          https://twitter.com/ClimateOfGavin/status/689889149189525504/photo/1

        3. Mike, the sceptical article in your link has a major error or blatant lie. Take your pick.

          The article claims that temperatures have only barely increased since 1998 and fail to meet model estimates at the “surface” and quotes satellite data.

          Satellites do not measure the surface, they measure the mid troposphere.

          Its true the mid troposphere is warming more slowly than the surface and its possible the satellite data is in error, or its just warming more slowly. It is indeed towards the lower bound of model estimates.

          However the surface data from NASA or NOAA from 1998 to 2016 shows quite strong warming since 1998 and roughly in line with model estimates.

          So the entire article is a waste of space. The real question is why are there discrepancies between satellite atmospheric data, and surface data, and anything else is just an empty bore of a discussion.

          Given we live on the surface and temperatures are measured using old and proven methods on land and in the oceans as well, I’m more inclined to pay attention to surface measurements.

    1. Andy, why SPAM your mention of the release of the T&T peer review with:

      “Coal Action Network got the result they wanted.”???

      What the Coal Action Network or anybody else may have hoped the panel would find is completely irrelevant. The peer review stands on its own merit. And obviously, the findings are what any right minded and science-educated person, who has read some of the relevant climate science would have expected. And I am not sorry at all that it is not what you would have wanted.

      Perhaps time (high noon more likely) to question your own paradigms?

      1. What the Coal Action Network or anybody else may have hoped the panel would find is completely irrelevant

        How is it irrelevant when Coal Action Network issued a press release demanding that “deniers” be removed from the panel?

        The residents of Christchurch at least now know about Coal Action Network and their modus operandi

        1. Andy, stop your silly attempt to deflect the news of the release of the report towards the Coal Action Network.

          The peer review of the T&T report here was the work of the appointed panel. And it is well worth reading.

          And yes Coal Action and others have wondered why known climate science deniers were appointed to a panel to review the T&T report. The report is clear in its findings.

            1. I have had a quick scan through this peer review report, and its crystal clear to me.

              The peer review report accepts the important one metre sea level rise criteria, and accepts the numbers of houses likely to be inundated by sea level rise.

              The report questions some calculations related to the separate issue of coastal erosion and just how many houses will be subject to erosion alone. Fine,whatever, they were always going to find something to criticise to justify their existence.

              The original report was subject to an unrealistically short time frame to do the best possible calculations and investigation on erosion. The original report made this clear.

              It is good that these calculations will be re-visited, and we will have a better outcome, although its probably not going to be much different. And these houses will be affected by sea level rise anyway.

              But the basic findings on sea level rise have been upheld. This is the biggie in terms of impact and precedents for what other councils do.

            2. Andy

              The peer review executive summary says in item 5) that the original Tonkin and Taylor report is based on the IPCC sea level rise projections for 2065 0f 0.27 – 0.47, and for 2115 of 0.62 – 1.27. Now that looks like 1 metre to me as the worst case for the time frame, so stop nit picking.

              The peer review doesnt question or criticise the use of these figures and notes the original report is required to consider both and says in section 41) that the use of them is acceptable.

              Of course the peer review is obviously not endorsing that they personally believe anything in particular in terms of sea level rise, but the point is they do not reject the sea level rise figures or interpretation of them.

              So stop nit picking and being pedantic. Just for once, because it proves nothing.

              Get over the whole thing and move on. You made your point that a peer review might be useful and got it.

              All your big doubts have been proven wrong. The peer review states in its conclusion that the report is fit for purpose. It makes a few criticisms on erosion but nothing huge or the conclusion would be different. It upholds the sea level rise components of the report. This may not suit you, but that’s tough.

              We now have quite a reasonable guide for other cities that sets benchmarks on the exact sea level and erosion analysis that is required. All good.

            3. The peer review is irrelevant to public policy. Final submissions have been made to the Independent Hearings Panel and they are most likely leaving sea level rise out of the District Plan at this stage. Under the Greater ChCh Regeneration Act 2016, no further changes to the plan can be made for another 5 years, or so I am told.

            4. The peer review doesn’t question or criticise the use of these figures

              What kind of peer review is this/ Other than one that cost the ratepayers $165,500 ?

            5. Andy

              The review obviously considered the issue of sea level rise, given the number of references they make to it. They simply didn’t criticise the figures used.

              From the media article in the link YOU posted local people were concerned about the use of a 1 metre sea level rise figure. The peer review has upheld the use of that figure as I pointed out.

            6. I counted around 29 references to RCP 8.5 in the review, and zero references to actual sea level data or trends.

            7. Andys says “I counted around 29 references to RCP 8.5 in the review, and zero references to actual sea level data or trends.”

              Thats good enough for me. T&T and the Peer review were never asked to provide an analysis or graphs of climate change theory or data trends. You can get that from the IPCC reports.

              The peer review only had to consider whether T&T were using sensible sea level rise figures from IPCC estimates, and that nothing unusual was in the report. T&T included quite some detail on whether the use of particular figures and risk levels was appropriate.

              You stated you were worried about the cost of the report (that you pushed for). It looks like good value for money to me. It’s quite a detailed report and makes some good points.

              Compare that to my lawyer who charges a fortune for what is often complete rubbish of no particular use or relevance.

            8. So you accept a sea level projection based on a scenario that explicitly states that it is not designed for public policy, and projects a world where we burn four times as much coal as there exists on the planet?

              You also accept a sea level projection that runs against the advice of the MfE?

            9. 1: The Peer Review explicitly notes that T&T’s use of RCP8.5 is reasonable, and use of “extreme” scenarios is common practice when assessing future risk.

              2: Projections of future SLR do not depend only on RCPs, they depend on modelled ice sheet response. Our understanding of that has advanced considerably since AR5 and the now-outdated MfE advice, and indicate that 1m by 2100 may not be particularly “extreme”. As Thomas notes, paleoclimate data makes it more or less certain that at 400ppm we are heading towards 6m of SLR – the only question is how long it will take to get there. No RCP required.

              3: There should be new MfE guidance at some point (fairly soon? – I’m not sure). At the very least, national guidance needs updating regularly to reflect advances in our understanding of climate impacts in NZ. I have argued that the NZ govt should be much more active in this area. I’d prefer something along the lines of an annual or biennial update to be considered alongside longer term policy statements.

            10. Thats good enough for me. T&T and the Peer review were never asked to provide an analysis or graphs of climate change theory or data trends. You can get that from the IPCC reports.

              which provide a range of scenarios, of which one metre is the worst case

            11. AndyS,

              I’m happy with the sea level rise data used. It appears conservative based on the latest science.

              As is pointed out its commonplace to base decisions on extreme scenarios. Basically its better to apply the precautionary principle, because its much easier to scale back things if information changes, than play catch up.

        2. Poor Andy, reality wins again – it’s so unfair!

          Never mind, laddie, if Trumplestiltskin wins the US election, facts and logic won’t matter any more.

        3. andyS hates it when dishonest people are exposed and are removed from any place where real and honest science is discussed. Just shows what sort of a person he is since he will not admit that to deny AGW is to be dishonest.

  12. nigelj and Thomas – while your strutting and crowing on dung hill is revealing, you have not acknowledged Andy’s take-away:
    “and from the report itself,
    [221] Thus, for the time being, the conclusions in the first and second stages should not extend to firm hazard lines designed to go into the LIM reports or for inclusion in the CRDP as maps or zones”

    In incremental politics this is a win for common sense.

    1. Mike, the peer review found the TT report fit for purpose (see conclusion). That is the main point.

      And note in this [221] paragraph the “for the time being” clause. And indeed as time moves on and further evidence is considered such hazard lines are part of what the council will certainly have to consider. However, as the review panel is also well aware, SLR is a moving target and no hazard lines will ever be “firm” but will need to be moved further and further inland. What we know for sure is that under the current CO2 content of the atmosphere we have committed humanity and CC to an SLR of serval meters with figures of 5 to 6 meters being considered by scientists. It puts the drawing of “firm hazard lines” into perspective for you Mike.

      http://www.scientificamerican.com/article/sea-level-could-rise-at-least-6-meters/

    2. Mike I just take a general interest in these issues. Maybe there’s some crowing because its human nature to do this when your own suspicions are confirmed. Andy runs around crowing about various scientific papers, almost beside himself with glee (usually the papers he quotes are a bit weak though).

      The more important point is that any dung hills (didn’t know you got these much in NZ) will be washed away by rising sea levels.

      I did acknowledge that the peer review report came with some criticisms / suggestions on a few issues, and its all to the good. Personally I think on an important issue like this with long term implications a couple of peer reviews are not a bad thing. I believe this is the second? But it will have to be the final one.

      However hazard lines will have to be defined and redefined. There’s no running away from this. Thomas has summed it all up.

      But the take away is that the peer review found the report fit for purpose, and the original concerns of the local people about excessively high sea level rise assumptions were not upheld.

      Our human psychology does not compute long term risks very well, and I’m sure you are probably aware of all this. We certainly need to try hard. We are at risk of locking in 6 metres of sea level rise and I would suggest considerably more. Some estimates are 30 metres, if all or most of the planets fossil fuels are burned. There is about 60 metres of sea level rise locked up in all ice sheets etc.

      I try to be an optimist and see that humanity would adapt, but it will be a long and expensive adaptation over many centuries, all because we are addicted to oil, and are being selfish short term thinkers.

      1. But the take away is that the peer review found the report fit for purpose, and the original concerns of the local people about excessively high sea level rise assumptions were not upheld

        This is completely untrue. The report did not consider the appropriateness of RCP8.5 at all.
        There is nothing “upheld” in this report.

        The community reference board will be making these points to the Ministry for Environment when we meet them sometime in August.

        1. You are wrong Andy or are misinterpreting what I’m saying, as you consistently do with everyone it seems.

          The peer review clearly stated that T&T had based their work on a variety of sea level rise assumptions from the IPCC, and that these assumptions were appropriate and that the overall report was fit for purpose.

          T&T were never required to consider whether the IPCC findings on sea level rise are scientifically valid, as far as I’m aware. Even if they have considered this it appears they do consider them valid. Obviously if they had massive reservations they would have said.

          In my view we would be very unwise to stray from the IPCC findings on sea level rise. I may be wrong but didn’t you say previously that T&T should follow IPCC estimates? So you are being very confusing.

          You obviously dont like the Peer Review findings or original T&T report on sea level rise. Well tough. How many peer reviews do you want until they tell you what you want to hear?

          Remember the Peer Review had a climate sceptic on the panel in De Lange! You cannot possibly suggest the panel was over taken by warmists. You had it all your way.

          1. No we didn’t have it all our way. We suggested Kesten Green would be an appropriate person to do an analysis of the forecasting, but he was dropped after a political advocacy group intervened. There are some allusions to the increasing uncertainties of SLR projections over time, but this is very lightly done in my view. Overall, the statistical analysis is very disappointing

            One metre sea level projections run counter to the MfE guidance. Furthermore, the CCC climate policy assumes a one metre SLR projection along with a two degree warming by 2115. These numbers are inconsistent with the RCP8.5 scenario, which has temperature projections much higher than this

            One assumes the one metre is just a number pulled out of a hat somewhere.

            1. Andy, you will never get things all your way and in fact nobody will. The point is the peer review team seems quite good on the whole.

              You might not like the findings of the statistician, but his qualifications are fine.

              The peer review team had a climate change sceptic on the team even though it was a very small team, and the overwhelming majority of climate scientists believe we are warming the climate. Studies suggest from 90 – 97% of climate scientists say we are warming the climate. So you were lucky to have a sceptic on the peer review team.

              As has been pointed out the MFE statements are well behind the latest science.

              Regarding one metre and 2 degree warming this may be inconsistent, or a typo. I dont know.

              However you are missing the point. Clearly the IPCC scenarios include from 2 – 6 degrees warming and the higher level one metre sea level rise would be towards 6 degrees warming. It is a possible scenario so must be considered as has been done.

              However the latest science suggests 1 metre is possible with much less than 6 degrees warming.

              Regardless as has been pointed out its commonplace for agencies to consider worst case scenarios and overall I think 1 metre is bang on when all things are considered.

              I don’t know why you are so uptight. This is all being done so that appropriate warnings can be put on LIMs (land information memorandums). This information presumably will include sea level rise data and would say what scenario is chosen, worst case or whatever. People then have information and its up to them what they do, and they will have their views on sea level rise. Its an exercise in providing information.

              If Council also make decisions on future land developments and their location, better to follow the precautionary principle.

            2. I’m not uptight. My new house is over 700m above sea level

              If 80% of NZ properties become worthless as a result of your junk science, then I could become one of the wealthiest home owners in the country

            3. If the worst case scenario of the IPCC is conservative and therefore a low ball estimate, would you accept that the IPCC reports are not fit for purpose?

            4. AndyS,

              “If 80% of NZ properties become worthless as a result of your junk science”

              You are just speculating, or wild guessing may be more likely. People have to live somewhere, and with immigration in NZ running constantly ahead of the ability of the country to provide housing, housing will always be in demand even if its in low lying areas.

              You seem to believe people live in a vacuum. They will look at information on LIMs and make decisions and will weigh up several things before making decisions. You cannot assume they will all not buy.

              Regardless local councils are caught in a bind. If they ignore warning people about sea level rise they could be in big trouble. It’s inevitable that information will be on Lims whether we like it or not.

              Most kiwis already know sea level rise is predicted to be an issue and I dont see 80% of houses losing value as we speak. The LIM issue only formalises things and provides details that are needed.

              And as sea level rises people will have to relocate and some houses will loose value. But it will be a drawn out process. We cannot stop or slow this process UNLESS we reduce CO2 emissions.

              The only junk science I can find are sceptical theories about cosmic rays, sunspot cycles, undersea volcanoes, arctic ice “recoveries” and so on ad nauseum like a huge dung hill about 3kms high.

              “If the worst case scenario of the IPCC is conservative and therefore a low ball estimate, would you accept that the IPCC reports are not fit for purpose?”

              No I wouldn’t. IPCC reports are fit for purpose because they are the best information we have at any point in time and being slightly conservative is standard practice in reports of this nature.

              Whether sea level rise decisions should be based on the last IPCC report or newer evidence depends on the strength of newer evidence. T&T do not live in a vacuum. However the last IPCC report estimated a worst case of 1 metre by early next century, and the latest science certainly doesn’t undermine this.

            5. You seem to believe people live in a vacuum. They will look at information on LIMs and make decisions and will weigh up several things before making decisions. You cannot assume they will all not buy

              Of course people will gravitate towards properties that they can afford, which in the case of Christchurch, will be the rat infested slums in the coastal east that are being devalued as we speak because of council policy.

              No one is going to invest in these areas because policy dictates that they have no future, regardless of any actual sea level rise

            6. Oh! I see you have now recalled who it was that suggested Green as the “statistician”.
              When telling porkies andy – you either have to be NZ’s PM or have a very good memory.

            7. Andy, its you pulls nonsense out of a hat time and time again, from linear extrapolation of low SLR figures with total disregard of the actual dynamics and the best science available to making up stuff as you go, wherever you go.

              BTW have a look what 2Deg of Warming means in the context of ChCh:
              http://ss6m.climatecentral.org/#13/-43.5144/172.7099

              Or for the Hauraki Plains:
              http://ss6m.climatecentral.org/#12/-37.2474/175.5763

              or the Bay of Plenty to the south of Tauranga…
              http://ss6m.climatecentral.org/#11/-37.8768/176.7762

          2. AndyS

            If councils warn people of climate change, there could be some property devaluation, although its hard to see it being drastic. This is because of high demand for housing in NZ generally pushing up prices (even with old leaky homes,) and the warning process is orderly and informative.

            If councils say nothing, and we all proceeded in denial of climate change, and there was no IPCC, 20 years or so from now there will almost certainly be a rude shock as reality starts to become more obvious. Then there will be a big panic, and devaluation could be drastic.

            Its “Hobsons choice” and has parallels with many other issues facing humanity.

  13. Yes it was me that suggested Green. I have already stated this. Since the interference of Coal Action Network in the process, we have a report that has no statistical input of any worth, and a ratepayer bill of $165,000 that is just a waste of time

      1. I said “I can’t remember all the names”

        There were a lot of names put forward. If you want to twist that into something else, that’s your issue

    1. Andy, Coal Action Network, and many others have publicly commented on the questionable choice of including deniers of climate science in a process of peer review of a science-driven report. This is the people’s democratic right. Luckily we do not live in China or Turkey or Russia among others, where the critique of government officials can be bad for your longevity…

      Do you suggest in earnest that the panel’s actual work was impeded or interfered with by Coal Action Network? Do you suggest that the review panelists did not undertake their work properly? If you believe this then you better produce some sound evidence to back this up as otherwise all you do is produce slanderous innuendo.

      You say the report had no statistical input of any worth? How on Earth can you say this?!? The work published by the IPCC and the science papers that underpin this and on which the T&T report is based are heavily informed by statistical analysis of climate data. In fact, statistics is central to about all climate science endeavors. And it was clearly NOT the brief of the peer review to re-hash climate science or undertake somehow a statistical re-analysis of IPCC publications!

      Get with it Andy. AGW is a globally accepted by the science community and SLR is a globally accepted reality. We now need to move forward towards negotiating how society will deal with and handle the massive losses to property and amenity that are coming our way because of it. This process will indeed be very painful for many. It will carry on for generations. And thanks to your motley foolish fellowship of deniers and fossil fuel industry shills, the pain and suffering for our children’s and great grand children’s generations will be significantly worse than if we had acted decisively and globally just 30 short years ago as suggested by science already then. Your party in all this will earn the curse of all curses for what you have done with your activism.

      1. The report claims that they can’t assign any likelihood to RCP8.5, and the attempts in the questions presented were meaningless

        I therefore conclude that the results of the T&T report projected out 100 years are also meaningless, and not fit for the purpose of drawing hazard lines, as in fact the peer review concludes.

        1. How would Kesten Green have assigned a likelihood to RCP8.5?
          Do you not see the irony? It is in your personal interest that RCP8.5 does not occur, and yet you try to encourage public opinion to make it happen.

          1. How would Kesten Green have assigned a likelihood to RCP8.5?

            I have no idea what Kesten would have said, with respect to RCP8.5 or any other matter. Thanks to Coal Action Network and their friends at the ChCh Press, we will never know

            1. Andy what Green thinks about the likelihood of RCP8.5 to happen is not even relevant to the debate. It is pointless as it is not the role of the CCC to waste tax payers money in order to rehash the global warming evidence or to question the statements of the IPCC. It is their duty though to assess the impact of the IPCC statements on CC.
              What Green thinks is public knowledge anyway:
              http://www.desmogblog.com/kesten-green

            2. Kesten Green doesn’t seem particularly “green” orientated, and appears to be a climate sceptic gun for hire.

              As far as CCC goes it is not Greens or his replacements job to review the science of climate change and predictions made by the IPCC.

              Green has expressed scepticism with the value of climate models and the science of making climate predictions.

              I dont see how he could possibly know. These models are based on very advanced physics. Green has no science qualifications, or something like physical geography, so how would he even know what half the terminology means?

              He has a business management degree of some kind, with a focus on forecasting, (his CV actually isnt very clear), but the maths and statistics of the climate models has already been checked a dozen times. He hasn’t got the qualifications to design climate models from scratch. I totally respect business and maths specialists, but the cross over to climate modelling would be hard. Probabilities are very tied into the science.

              Just on these sea level rise and erosion hazard lines on maps, apparently the 100 year predictions are deemed a difficulty as they are a long way into the future. Buildings in NZ are required to have 50 years durability under the building code, implying a 5o year life. Of course we know they may last nearer 80 years, but maybe 50 years is not a bad time frame to base LIM information on sea level rise and draw lines on maps. However it will be a constantly moving target that has to be constantly upgraded. Such is the price we pay for continuing to burn fossil fuels like crazy.

            3. The Tonkin and Taylor report, and therefore Christchurch City Council, plan for 0.4m SLR by 20165, and 1m by 2115

              If you try to fit a second order polynomial to these data points, you will soon see that the claims are mathematically implausible.

            4. AndyS

              It does seem that a second order polynomial curve would not easily fit that particular data. If it was 300mm by 2065 a curve would appear to fit easily. I’m just eye balling the following graph as a basis to get some sense of what you are saying.

              http://www.mfe.govt.nz/publications/climate-change/preparing-coastal-change-guide-local-government-new-zealand/part-one

              I don’t have time to read the full T&T report to see what all their thinking is or what baselines they have used etc. Maybe they are using a complex curve, or are just being deliberately precautionary in their selection of 400mm by 2065. You haven’t really given the full picture of what they are saying, or proven theres a problem.

              The difference between 300mm and 400mm is one thing, but the more important issue is 1000 mm by end of century, and a 2 degree temperature rise risks locking in 6 metres of sea level rise.

            5. Nigel
              You can see the parameters for the sea level assumptions here

              http://bit.ly/2azNfGZ

              The initial SLR has to be three times the current rate, plus an acceleration unseen anywhere

              Interestingly, if you change the 40cm to 30cm, the initial sea level rise is about correct, but the acceleration gets doubled to 0.16 mm yr-2 (twice the second parameter in the equation)

              which would yield a short time to see a significant SLR acceleration

            6. Andy, what is it with you that you always seem to assume that nobody checks your claims and statements here? I teach mathematics so I knew your claims are tosh without even looking. But I did anyway so, I quickly put the numbers:
              2000 0
              2065 0.4
              2115 1
              into Excel and made a scatter plot with a 2nd order polynomial.
              (assuming 2000 = 0 = baseline for this plot , 2065 + 0.4m and 2115 + 1.0m)
              Guess what: A perfect fit of the data to a 2nd order polynomial!

              Not only is the curve fitting perfectly, you should know (if you actually had any background in Math, that it must fit perfectly given ANY three points from 1st principles of curve fitting which is year 12 math at high school.
              y=ax^2+bx+c requires obviously three points to fit a parabola perfectly.

              I find it once more highly implausible that you have a tertiary education in Mathematics.

              So Andy, what was that again all about? Duh!

            7. Yes, Thomas, I know that 3 points can fit a second order polynomial. I’m glad that you don’t need to check my work before criticising it because you know it is tosh

              The link i gave to Wolphram Alpha gives the paramters for the second order polynomial that you know is tosh

            8. Andy at 50|33 your data fit the initial current global gradient of 3.2 mm/y perfectly. That is only 7mm of the 40 cm assumed by T&T at a 50-year horizon.
              But taking the emerging picture of Arctic melt into account plus deepening knowledge about the vulnerability of the Antarctic ice shelves, and we are likely going to see a sooner acceleration of the trend. And who says that SLR must be a quadratic progression anyway?

            9. AndyS

              Thomas is right. I missread the bottom axis of the graph in my link as 2060 rather than 2050. The 400mm data points and 1000mm data points are on a quadratic curve projected from current NZ sea level rise trends.

              The report has been peer reviewed. Its extremely unlikely that there would be a mistake in the basic maths or graphs.

            10. If you look at my link, the parameters of the quadratic that fits the 40cm/100cm projection would imply an initial SLR of 6mm a year which is 3 times the local rate.

              If you assume a 30cm/100cm over 50/100 years, the initial SLR is about 2mm / year but the acceleration would be double the previous case (you can play with these numbers in the Wolfram Alpha link I provided)

              This fits the initial conditions but assumes an acceleration that is higher than anything seen on the planet, and that would yield a SLR at 100 years that is just under 2cm / year. MfE recommend planning for 1cm / year beyond 2100

        2. Andy it is NOT the role of the peer review of the TT report to rehash the likelihood of the pathways of the IPCC scenarios occurring. That is NOT their brief obviously. This is the task of the IPCC and is included in their reports.

          Besides the peer review states in their exec summary:

          [4] Tonkin & Taylor consulted with CCC on the use of RCP8.5. We note that the RCP8.5 is referred to as a ‘business as usual’ scenario in both Ramsay et al (2012) and MfE (2008b) and also that it represents the effects of a very high emission scenario based on exclusion of future additional efforts to constrain emissions and very high population growth, and is commonly used in hazard assessments.

          … and obviously confirms once again that the RCP8.5 is commonly used in hazard assessments.

          And as ever and always Andy, you mistakenly assume that uncertainties go only your way i.e. SLR will likely be less than what is projected in the IPCC pathways. In fact, we know from recent research that there is a considerable risk that SLR projections of the IPCC may well be too conservative.

          Back to the realization Andy, that our inaction has condemned humanity to live with rising sea levels for generations with the “end” of all this likely to be well into double-digit meter SLR. Your bickering about what the CCC should or should not do in order to warn its citizens and potential property buyers and developers is groundless. So stop your yapping. Its pointless.

  14. AndyS

    Thanks. You are trying to derive a quadratic formula and set of sea level rise projections that provides a completely smooth transition to the historic NZ sea level rise data.

    This is mathematically elegant, but is NOT the right approach.

    Firstly the transition from the roughly linear NZ trend to a curve doesn’t have to be perfectly smooth. (In fact it should be noted that it is certainly reasonably smooth, remarkably so).

    We have to take the globally averaged sea level rise projections and simply “graft” them onto the historic NZ sea level rise data. The globally averaged projections use a zero starting assumption, 400mm and 1000 mm and are a quadratic curve. I have already shown you a graph of this grafted on to the NZ historic data.

    The only reason we would do otherwise is if we knew there were significant geological conditions long term in NZ that would mean the IPCC projections were unrealistic. With uplift of 0.5mm year this just isnt very significant. Clearly T&T have seen no reason to take another approach to the IPCC projections.

    So the projections of 400mm and 1000mm are valid.

    1. So the projections of 400mm and 1000mm are valid.

      these require an initial SLR of 6mm / year and an acceleration that is yet to manifest in local conditions.

      I fail to see how this is valid.

      1. AndyS,

        The 400 / 1000 points do not require a slope of 6mm. Look at this link, second graph down the page.

        http://www.mfe.govt.nz/publications/climate-change/preparing-coastal-change-guide-local-government-new-zealand/part-one

        They have spliced on the curve from about 1990 at about the end of the tidal gauge data. I think this is because we only have limited satellite data, so the tidal gauge data is taken as the benchmark data.

        The average slope of the graph at around 1990 looks like about 2.5mm to me. Therefore the splice has a slight inflection and is not completely smooth however a slight inflection is plausible. I understand your point that the transition should be smooth and this might require 6mm year, but it doesnt HAVE to be completely smooth. As long as its reasonably smooth.

        I see nothing in this graph that worries me.

        1. “The 400 / 1000 points do not require a slope of 6mm”

          yes they do. I gave a mathematical reason, you gave a graph to eyeball

          eyeballing graphs from powerpoint slides isn’t actually science

          1. Andy, your nitpickery about slopes and gradients with regard to CC is irrelevant.

            The rate of acceleration of SLR in the future depends on many factors and feedbacks and also on our actions to revert the CO2 trend or the lack of the same. Your mathematical number play will have no impact on that whatsoever, nor will it inform you or the CCC about prudent methods of risk management.

            We know for sure that the processes we kicked into motion will result in many meters of SLR and all the latest science point to this coming sooner than predicted by the IPCC a decade ago. With regards to CC local geological impacts (as in the last Earthquake) make firm predictions even harder and call for an extra margin of uncertainty – both ways! – in the estimates. Some areas of CC lost 1m in elevation overnight in the big quake! Your gradient play or worry about a few mm more or less mid-century is simply totally silly.

            Now let’s move on towards developing a nationwide solution that allows councils and property owners and buyers, banks and insurance companies to refer to a legislative structure that deals with the consequences of the loss of significant and productive areas of NZ to the oceans.

            http://ss6m.climatecentral.org/#11/-43.3923/173.0127

            The sooner we bring this sad topic to the front page of our political agenda, the better as it might move people and the government towards acting with more vigour towards emissions regulations and a pathway to ending our fossil fuel dependency.

            1. …. and if you think CC will be hard done by in a 2 Deg warmer world… have a look at Invercargill! http://ss6m.climatecentral.org/#12/-46.4167/168.3349
              I guess if Tim Shadbolt takes a look at this (are you listening) then he will soon be knocking at the PM’s door to ask what National is doing to prevent his town from disappearing under the seas….

          2. Andy, you gave a respectable mathematical reason that belongs in a text book. No disrespect intended.

            Here is the real world situation as I see it.

            NZ has had a 2mm approx. sea level rise trend over the last 100 years, and its largely driven by actual sea level rise. The graph I depicted spliced on a 0, 400, 1000 quadratic (approximately) with a starting acceleration of 6mm (according to your calculation). Where the linear trend meets the curve there is a small angle or inclination, ie its not entirely smooth.

            It is perfectly possible that a linear trend of 2mm or so could change suddenly to a 6mm quadratic in the REAL WORLD. Not all that likely but possible. Remember the historic trend in NZ is not 100% accurately known, and is partly governed by geological factors that can slow down and speed up. And for all we know recent sea level rise could be near 6mm. We are in margin of error stuff on the whole matter.

            Please also note that the graph in the link I posted shows the curve starting from 1990 approximately and since that point sea levels have started to accelerate to 3.5mm and are thus getting near the 6mm slope of the curve exactly as we would expect. This is very compelling evidence that the curve is a feasible curve in the real world.

            Of course some locations around the world have had very little sea level rise over the last 100 years due to powerful local geology, and this suggests future sea level rise would be limited. Splicing on a 0, 400, 1000 quadratic would be very abrupt, and not be feasible practically and very untidy mathematically. But NZ is not in this category.

    2. Quite correct. And also in particular with CC and other NZ locations, the slight geological uplift may we all wiped out by the next earthquake anyway, which adds a significant extra margin of error any planning should take into consideration. The big quake caused subsidence between 0.5 and 1m in parts of the city.

      An interesting read is this article: “The sinking city: Earthquakes increase flood hazard in Christchurch, New Zealand” (see link below)
      http://www.geosociety.org/gsatoday/archive/25/3/article/i1052-5173-25-3-4.htm

      So Andy’s desperate attempts to forestall CCC planning for SLR with reference to local differences of SLR compared to the global average are rather silly and more like playing Russian Roulet while hoping that perhaps none of the chambers are loaded….

      1. Andy, has the thought ever crossed your mind, or that of the CCRU, that due to strengthening concerns over the rate of sea level rise based on research not yet included in the last IPCC reports the new maps and their hazard lines may well be further inland than the initial ones?
        The issue for the CCRU is far from the table indeed and no crowing over this will hold back the SLR….

  15. Sure Andy, the pains of having to deal with the reality of climate change and the sharp end of seal level rise are not going to be easy. This little battle of the residents of at risk ChCh properties against the reality of their situation is just the very tiny tip of the proverbial iceberg. Its is a beginning of the pains of coming to terms with a world that slowly but inevitably going to do what it will in response to our release of CO2.
    The sooner we start to make serious plans to deal with all this the better.

    1. andy forgot to add this:

      Disclaimer: This material is being kept online for historical purposes. Though accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information,

      It was published in 2012 so in terms of the current science is outdated.

      Furthermore – andy’s link is of little relevance to the question posed by Tony. The question was (paraphrased) “when was the last time both poles were melting?”
      andy conveniently over looks the simple fact that the coldest place on Earth (Antarctica) is warming, yet is still cold enough in many places for ice to form. West Antarctica is one of the most rapidly warming regions on the Earth and the Pine Island and Larsen A and Larsen B are calving at ever increasing rates and ice shelves are thinning – but then it seems andy is far more concerned about the plight of eagles than adele penguins.

      1. “but then it seems andy is far more concerned about the plight of eagles than adele penguins.”

        that seems like a fairly big inference from my one line response

        1. andy, we all here know of your indifference to the melting and disappearance of Antarctica’s Ice Shelves. Your consistent inability to accept that it is happening, with your constant denial of the current rate of SLR speaks volumes. Those of us who have been readers and commentators on Gareth’s excellent blog for a while now also know that you have an abhorrence of “bird choppers” – in particular their supposed kill rate of unsuspecting eagles. Yet the projected demise of adele penguins from loss of habitat and the warming Southern Ocean doesn’t seem to cause the same level of concern after the rather obvious link to superseded data suggesting Antarctica is not melting.

          1. It seems a little unreasonable to claim that am indifferent to the plight of the Adélie Penguin when in fact I was unaware of them until you brought up the topic.

            Merely looking at the pictures on the Wikipedia page for them suggests that large colonies exist

            https://en.wikipedia.org/wiki/Ad%C3%A9lie_penguin

            I’m a little more concerned about birdlife closer to home, particularly the Black Stilt, which DoC are re-introducing to the Mackenzie (My new backyard)
            The population dropped to a mere 23 birds and now is 100 thanks to a breeding programme, but is still listed as critically endangered.

            The main threats to this and other species in the area is predators and land use changes

            1. yep the land use changes are certainly a major threat especially in Canterbury. Haven’t seen a Black Stilt but we did have the more common Pied Stilt visit us when we were regenerating our wetland, along with a little pied shag. Now we live on the sea bird coast and the congregation and variety of sea birds here has to be seen to be believed. Royal spoonbills, Kotuku, oyster catchers galore (when the tide is in Kuranui Bay just north of the town is literally covered in thousands of birds waiting for the tide to go out and to feed), Godwits, Wrybills, and Dotterels, to name a few.

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