Are we feeling warmer yet?
Richard | November 25, 2009 | 4:01 pmThe New Zealand
Climate Science Coalition
25 November 2009
(A paper collated by Richard Treadgold, of the Climate Conversation Group, from a combined research project undertaken by members of the Climate Conversation Group and the New Zealand Climate Science Coalition)
There have been strident claims that New Zealand is warming. The Inter-governmental Panel on Climate Change (IPCC), among other organisations and scientists, allege that, along with the rest of the world, we have been heating up for over 100 years.
But now, a simple check of publicly-available information proves these claims wrong. In fact, New Zealand’s temperature has been remarkably stable for a century and a half. So what’s going on?
New Zealand’s National Institute of Water & Atmospheric Research (NIWA) is responsible for New Zealand’s National Climate Database. This database, available online, holds all New Zealand’s climate data, including temperature readings, since the 1850s. Anybody can go and get the data for free. That’s what we did, and we made our own graph.
Go to paper
Download paper (pdf, 213KB).
Seems credible enough, until you realise Richard that you haven’t accounted for site changes for the temp. adjustments. As you well know, a site change from sea level to a few hundred metres above, will mean a paradigm shift in recorded data sets, most easily shown in Wellington, with the changes from Thorndorn, Kelburn and Airport sites. So the adjustments done by NIWA isn’t some great conspiricy to show warming, it simly is accepted meteorological practice, and has been the case for decades.
Yes, good point, Tim; it’s the whole point of our study, really. We cannot account for adjustments, because we don’t know what they are. We ask only to know the adjustments that have been made, in detail, for all seven stations, and why. We note that, though they mention Wellington as an example, they still provide no details. As public servants they have no good reason to refuse our request. We allege no “conspiracy”, we say what is true: that no warming is evident until after the adjustments. Vibrant language, perhaps, but it has succeeded in shaking the tree and forcing a response from an organisation which has steadfastly refused to answer our scientists’ valid questions on this subject for many years. Surprised? – Richard
Um Richard, your leed headline grabbing statement in this “reasearch” is:
“But now, a simple check of publicly-available information proves these claims wrong. In fact, New Zealand’s temperature has been remarkably stable for a century and a half”
If you knew the data u used has been adjusted by NZ Scientists before writing this article, than you can only have arrived at your statement if your starting on an assumption that NZ scientists lie about climate change (ie they adjust it to meet their views without any reason) until proven otherwise.
Otherwise your statement would have been something like:
“the only publicily available information is of base data from different monitoring points in NZ, without adjustments this data presents a steady tempreature for a centuary and a half. So the question begs, what are the adjustments that justify NZ scientist showing a warming trend?”
You complete scaremongering begs the question – why would climate scientists want to release information to people like yourself, who than use it in a knowlingly misrepresentative and misleading manner on such a serious issue?
You are actually providing a very good defence for the UK scientists dislike of FOI requests from laymen skeptics.
NIWA have stonewalled us for years, literally for years, and refused to release the changes. In our article, we shook the tree, so, amazingly, it was tabled in the House and a question was asked of the Minister; now, that public information everybody has been entitled to see is, we hope, about to be released. We hope there are valid reasons for their adjustments, and we have no reason to think otherwise, but if they continue to refuse to tell us what they are, I hope you are prepared to transfer your understandable annoyance to NIWA. – Richard
It’s very hard to match your description (name or data ranges) with the stations in the NIWA database. I’d like to be able to pull your data from the NIWA archive of raw data. What precise stations and date ranges did you use?
I will ask the scientific team for the station IDs and get back to you later. – Richard
I find this all quite interesting. I happen to think the data adjustment is valid at times. Though in my field I am used to authors clearly documenting raw and adjusted data. As well as doing sensitivity analyses (adding and removing poor data or heavily weighted data) to see if the conclusion still hold true.
I will add that the Wellington explanation is still somewhat tenuous as they do not show any data contemporaneous with Thorndon. The claim that the Airport and Thorndon will be within 0.1°C of each other because they are at identical altitudes seems a little optimistic. (I have posted on this in more detail.)
Yes, adjustments can of course be valid. The point here is that they’ve refused to disclose them, even when asked to do so by scientists working in the field. – Richard
Richard:
But does you Pdf file list the adjustments that were made?
No, we are unable to list them, since we don’t know what they were. That’s why we’ve asked for them. I wonder, have you actually read our article? – Richard
By the way, I’ve added an html version of the study so you can see it online without having to download a pdf. – Richard
Nonsense. At each location, there are a number of stations that have been operating for different lengths of time. Wellington has 30, 9 of which have the annual averages you used in your graphs. Many of these stations are no longer active (like Thorndon), and for each, start and end dates and many other important details (like elevation) are right there in the database. To make your graphs, you therefore had to combine data from different stations for each locality. However, you chose not to tell us that or show us at what points in your graphs there were changes in thermometer location; and you wrote that there was nothing in the ’station’ histories that warranted adjustments. For changes in elevation this is clearly false, and it’s very difficult to believe that your ’scientists’ wouldn’t have been aware of that.
So, I have some questions for you: why did you not tell us where there were changes in thermometer location on each of your graphs? How did you choose at what points to make those changes? Why do you not think such changes (’anything in the station histories’) are significant? And why do you continue to maintain that NIWA has refused to answer your questions when you say yourself that one of their scientists provided their adjusted dataset for each location, and when the station information available in the database allows you to build your own graphs and see exactly when and what adjustments have been made?
I’ll ask the scientists. I can say that the data we obtained from Dr Salinger’s colleague showed the output, but not the method used. – Richard
Yes, adjustments can of course be valid. The point here is that they’ve refused to disclose them, even when asked to do so by scientists working in the field.
Yes, and more than that, they should have labelled the graph adjusted as well as specify how it was adjusted without being asked.
We couldn’t agree more. – Richard
Richard, are there any large beef, sheep or “other” stations or institutions, nationwide, which have been in the same family for generations, who have kept historical records over several decades, using the same form of measurement?
If so, wouldn’t their records be far more accurate than NIWA stations which tinker around with shifting, and possible placing thermometers in “conditions” which may not replicate those of the previous locations?
Surely somewhere there are longstanding, consistent, comparable records, which don’t have either confounders or variables?
Yes, no doubt there could be such stations tucked away around the country. But I don’t think there’s an issue with the management or the quality of the stations JUST BECAUSE they’ve been run by the government service. There are quality issues, sure, as you might expect on old pieces of equipment and old records. The scientists know more about that than I do, but I have not heard anybody suggesting we should replace the official sites.
Tauranga have records going back to 1913
http://www.bayofplentytimes.co.nz/local/news/city-slips-to-fifth-in-sunshine-survey/3760620/
That’s a long time ago, to be sure.
[...] myths arise from a misinterpretation of the paper we published last November, Are we feeling warmer yet?, which questions the official national temperature graph produced by NIWA (available on their web [...]