More on the NIWA New Zealand data adjustment story

NIWA issued a response statement regarding the charges leveled by The NZ Climate Science Coalition here:

http://www.niwa.co.nz/our-science/climate/news/all/niwa-confirms-temperature-rise

They say:

Warming over New Zealand through the past century is unequivocal.

NIWA’s analysis of measured temperatures uses internationally accepted techniques, including making adjustments for changes such as movement of measurement sites. For example, in Wellington, early temperature measurements were made near sea level, but in 1928 the measurement site was moved from Thorndon (3 metres above sea level) to Kelburn (125 m above sea level). The Kelburn site is on average 0.8°C cooler than Thorndon, because of the extra height above sea level.

I’m not too impressed, especially when you see where the weather station for National Institute of Water and Atmosphere (NIWA) is, right on the rooftop next to the air conditioners:

Note also the anemometer mast, identifying the weather station Click for a larger image

Here is the station survey: NIWA_station_survey (PDF) and the Google Earth KML file

Thanks to: Dieuwe de Boer who did a good portion of station surveys in New Zealand last year.

The NZ Climate Science Coalition responds:

NIWA’s explanation raises major new questions

The NIWA climate controversy took a new twist tonight with the release of new data from the government run climate agency.

Reeling from claims that it has massaged data to show a 150 year warming trend where there isn’t one, NIWA’s chief climate scientist David Wratt, an IPCC vice-chair on the 2007 AR4 report, issued a news release stating adjustments had been made to compensate for changes in sensor locations over the years.

While such an adjustment is valid, it needs to be fully explained so other scientists can test the reasonableness of the adjustment.

Wratt is refusing to release data his organisation claims to have justifying adjustments on other weather stations, meaning the science cannot be reviewed. However, he has released information relating to Wellington temperature readings, and they make for interesting reading.

Here’s the rub. Up until 1927, temperatures for Wellington had been taken at Thorndon, only 3 m above sea level and an inner-city suburb. That station closed and, as I suspected in my earlier post, there is no overlap data allowing a comparison between Thorndon and Kelburn, where the gauge moved, at an altitude of 135 metres.

With no overlap of continuous temperature readings from both sites, there is no way to truly know how temperatures should be properly adjusted to compensate for the location shift.

Wratt told Investigate earlier there was international agreement on how to make temperature adjustments, and in the news release tonight he elaborates on that:

“Thus, if one measurement station is closed (or data missing for a period), it is acceptable to replace it with another nearby site provided an adjustment is made to the average temperature difference between the sites.”

Except, except, it all hinges on the quality of the reasoning that goes into making that adjustment. If it were me, I would have slung up a temperature station in the disused location again and worked out over a year the average offset between Thorndon and Kelburn. It’s not perfect, after all we are talking about a switch in 1928, but it would be something. But NIWA didn’t do that.

Instead, as their news release records, they simply guessed that the readings taken at Wellington Airport would be similar to Thorndon, simply because both sites are only a few metres above sea level.

Airport records temps about 0.79C above Kelburn on average, so NIWA simply said to themselves, “that’ll do” and made the Airport/Kelburn offset the official offset for Thorndon/Kelburn as well, even though no comparison study of the latter scenario has ever been done.

Here’s the raw data, from NIWA tonight, illustrating temp readings at their three Wellington locations since 1900:

What’s interesting is that if you leave Kelburn out of the equation, Thorndon in 1910 is not far below Airport 2010. Perhaps that gave NIWA some confidence that the two locations were equivalent, but I’m betting Thorndon a hundred years ago was very different from an international airport now.

Nonetheless, NIWA took its one-size-fits all “adjustment and altered Thordon and the Airport to match Kelburn for the sake of the data on their website and for official climate purposes.

In their own words, NIWA describe their logic thus.

  • Where there is an overlap in time between two records (such as Wellington Airport and Kelburn), it is a simple matter to calculate the average offset and adjust one site relative to the other.
  • Wellington Airport is +0.79°C warmer than Kelburn, which matches well with measurements in many parts of the world for how rapidly temperature decreases with altitude.
  • Thorndon (closed 31 Dec 1927) has no overlap with Kelburn (opened 1 Jan 1928). For the purpose of illustration, we have applied the same offset to Thorndon as was calculated for the Airport.
  • The final “adjusted” temperature curve is used to draw inferences about Wellington temperature change over the 20th century. The records must be adjusted for the change to a different Wellington location

Now, it may be that there was a good and obvious reason to adjust Wellington temps. My question remains, however: is applying a temperature example from 15km away in a different climate zone a valid way of rearranging historical data?

And my other question to David Wratt also remains: we’d all like to see the metholdology and reasoning behind adjustments on all the other sites as well.

Advertisements

  Subscribe  
newest oldest most voted
Notify of

This is the important sentence, methinks:
‘NIWA’s analysis of measured temperatures uses internationally accepted techniques, …’
Thanks to ClimateGate, we now all know what these ‘internationally accepted techniques’ look like, and we all know what ‘internationally accepted’ stands for.

Fred from Canuckistan . . .

The Climate Science cookbook will soon be published.
There is only one ingredient – Data
There is only one recipe – cook the data until it looks like what you want it to.
Data doesn’t mind being tortured.

Ron de Haan

That’s what I call “a case”.
I am looking forward to the response of this “scientists”.

When there is overlap, is it possible that weather stations tend to be moved due to change of usage in location – and that therefore they are more likely to be in UHIs at the time of their switch off. They therefore tend to be warmer than the replacement because they were warming up prior to being turned off. Is there any general tendancy for stations with overlaps to be warmer than their replacements?

CodeTech

uses internationally accepted techniques

Ah, I see… so because it’s “accepted” automatically means it’s right, right?
Perhaps that method is “peer reviewed”…
My favorite line is:

NIWA scientists are committed to providing robust information to help all New Zealanders make good decisions.

It reminds me of NOAA. Mmmm…. robust…

Rob

If there is an old site closing down and a new one opening up, why would they wanna splice them, regarding them as one station that has moved? There is the old station and the new.
Why not simply accept that some stations has data for a certain range of years and that other stations has data for other ranges of years?
When all stations have been averaged together, each and every station will only contribute with measured data, no adjustments (guesses).
Anyone knows about the urge to splice them and consider stations “moved”?

G. Borba

From the NIWA_station_survey:
“AS2922 compliant?
No: but not deemed necessary as site purpose is to monitor peak pollutant levels.”
Gary

Brian Macker

The best thing to do would be to treat a new location as a new location. No attempt should be made to fake up the new location as if it were the same. Likewise when parking lots are added or trees cut down then the location should again be treated as a complete new data set. That would be a much more honest and accurate account for the data.
Question is, did the skeptics treat the new locations as such. If they didn’t then they need to.

So NIWA is taking the “circle the wagons” route, too?
I have always maintained that the real danger from the Alarmist crowd is that because of their wolf-crying over ‘global warming,’ no one will listen when (and if) the world is ever faced with a REAL man-made environmental disaster.

Ron de Haan

The final push for the IPCC: The Greenhouse DOES NOT EXIST.
Following an extensive theoretical analysis, two German physicists have determined that the term greenhouse gas is a misnomer and that the greenhouse effect appears to violate basic laws of physics.
“The point discussed here was to answer the question, whether the supposed atmospheric effect has a physical basis. This is not the case. In summary, there is no atmospheric greenhouse effect, in particular CO2-greenhouse effect, in theoretical physics and engineering thermodynamics. Thus it is illegitimate to deduce predictions which provide a consulting solution for economics and intergovernmental policy”.
This is what Hans Schreuder is telling for years now: http://www.ilovemycarbondioxide.com
Read the entire article and download a pdf here:
http://www.americanthinker.com/2009/11/politics_and_greenhouse_gasses.html

Richard

Details, details. Just trust us okay? [pat on the head] Now go play with your hockey sticks. And watch out for those Yamal trees.

Gary Plyler

I would hope that you Kiwis are going to use a Freedom Of Information Act filing, if you have one down there. Hopefully expedited.
I got so ticked when I read:
” Wratt is refusing to release data his organisation claims to have justifying adjustments on other weather stations, meaning the science cannot be reviewed. ”
That’s the whole point of the problem.
What was ALL the raw data, how, why, and by how much was it homogenized, gridded, teased, etc.?
Which stations were not used and why?

Lazarus Long

“If you torture data sufficiently, it will confess to almost anything.”
-Fred Menger

Quite honestly, as a total Climate amateur, I could have done a better job of fudging data than these hacks seem to have done, (in both the US and New Zealand!). There isn’t even the veneer of scientific rationale present in any of their “adjustments”. As I’ve said several times over the years, I’m thankful that Cancer Research Scientists are slightly more ethical than Climate Scientists! A “cure” for Cancer would reap much more in $$ than “Global Warming Catastrophe” payouts, so I’m amazed they share data and protocols much more readily. Can any Climate Research actually be replicated?

Pamela Gray

This is a prime example of the utter disregard for the well-known climate zone theory. Climate scientists seem to not understand this phenomenon at all! Yet zoning of climate has been part of agricultural history for decades longer than many sensors have been in operation. Climate zones are understood by organic typography and altitude, as well as by non-organic typography (land use, urbanization, etc), in relationship to weather factors (weather data including extremes, jet stream location, typical pressure gradients, typical cloud formations, and storm type and history). To fill in missing data or to adjust the data of a new location by altitude alone is so incredibly uninformed that it escapes my understanding of why these people would call themselves scientists.
It reminds me of tree ring interpretations by a scientist who has never cleared or planted trees, nor logged and graded them in his entire life.

hengav

The direct linc to how the corrections were applied. Lower the old data by a degree. Lover the airport tarmac data by less than half a degree. Presto Chango.
http://www.niwa.co.nz/our-science/climate/news/all/niwa-confirms-temperature-rise/combining-temperature-data-from-multiple-sites-in-wellington

Brian Macker

Hey Rob didn’t see your comment till now. Exactly right.

Ed

I think the proper terminology is now “climate analysts” and not “climate scientists”. What CRU and friends engaged in is not science.
Climatologist or climate scientist is replaced with “climate analyst”
Climate science is replaced with “climate analysis”
Example: “Phil Jones is a climate analyst at CRU which studies issues related to climate analysis”.

Alan Millar

“NIWA’s analysis of measured temperatures uses internationally accepted techniques”
What are the odds that these ‘internationally accepted techniques’ are those from GISS, designed by the wonderful James Hanson. The man who has the most to lose if the AGW hypothesis is discredited. The man who has stated under oath in court that it is acceptable to break the law in furtherance of the AGW alarm agenda.
Alan

Dr A Burns

I was under the impression that the IPCC/Hadley/CRU approach was to take a mean for each station over some time period and to track offsets to show either warming or cooling trends. If this is done there should be no need for any such “adjustments”. Is this correct ?

Gene Nemetz

Fred from Canuckistan . . . (10:52:30) :
The Climate Science cookbook will soon be published….There is only one recipe – cook the data
The Mann Hansen Briffa Santer Schmidt cake. But I think ClimateGate slammed the oven door while baking and the cake fell.

Ron de Haan
Gene Nemetz

Fred from Canuckistan . . . (10:52:30) :
There is only one recipe – cook the data
What’s the oven temperature setting for that? Are we supposed to adjust it up to compensate for cooler than expected temperature in the recipe?

EJ

Why is he refusing to release the other data???
Another IPCC lead going down in flames I guess.

Al

I’m becoming more convinced that the mere act of opening and closing stations can introduce issues. Neglecting to ever run an overlap period, microsite issues, UHI – all serious. But I don’t see any correction for the full amount of “Station Closure Anomaly Adjustment” in the code we’ve got.
Picture the US for an instant, and pretend we have only seven stations (these are fake yearly anomalies in C).
Seattle: -1
Spokane: +5
Missoula: -4
Bismark: +3
Chicago: -1
Buffalo: -4
NYC: +2
If you’re just averaging, you’ll get zero. If you’re calculating gridcells, it is obviously more complex. Pretend for a second that this is one dimensional, and that these seven cells are the only ones used. So, in this simplified gridcell arrangement, you also get zero.
But what happens when, say, Missoula goes offline?
There’s the direct effect: the average is going to shift upwards by (+4/7).
But there’s also the gridding effect: We still have seven cells, but we have no reading for Missoula. How can we get a reading for Missoula? Well, the preferred technique is to find the two nearest know values (Spokane and Bismark) and interpolate. That would make an estimate of 4C for Missoula.
So the effect of dropping a local minima isn’t (4/7), it will be (8/7). The numbers I’ve used are made up – but what happens when you drop the only station in a section of the Rockies?
Fundamentally, this is saying that opening and closing stations directly affects the calibration of the instrument you’re using to determine “US Surface Temperatures.” You can have perfect siting and measurement across North America where every individual thermometer shows a completely flat century trend – and yet have an overall substantial increase or decrease based entirely on dropping (for whatever reason) the correct stations.
The very approach of calculating “US Average Surface Temperatures” from ground based thermometers has issues as implemented.

Frank K.

“Wratt is refusing to release data his organisation claims to have justifying adjustments on other weather stations, meaning the science cannot be reviewed.”
which is in direct contrast to:
“NIWA scientists are committed to providing robust information to help all New Zealanders make good decisions.”
What more can you say?
“Warming over New Zealand through the past century is unequivocal.”
Yup…

hunter

If they had a reasonable explanation for what they were doing, then those reasonable reasons would not have been produced only after they are caught diddling the numbers according to ‘internationally accepted standards’.
Lodging the weather station next to the AC blowers only demonstrates the utter lack of seriousness with which they treat their responsibility for accuracy and honesty.
Anyone involved in the leadership of the aGW movement, particularly as they get closer and closer to the IPCC, under scrutiny, will prove to be a bad player by the time this is fully exposed.
Rob,
SImply being honest, and showing that data series have windows of accuracy,
would be far too honest of an approach for cliamte scientists.
AGW: The more you know, the more you know you have been had.
AGW: the theory that does for climate science what Lysenkoism did for biology!

Detestible

Correct me if I’m wrong here, but wouldn’t more thermometers actually give a more accurate reading of what is happening?
For example. Instead of moving the temperature station from where it was at and adding another one actually improve accuracy? After all we are talking about “global” warming. So maybe I just don’t fully understand, but it seems to me the more thermometers they have the more chance they have of actually being accurate.

Sandy

Bin the dataset then, there are longer uninterrupted ones for NZ (which show no warming I gather)

Peter

There is a lot more to go on this story yet. On 27/11/09 Minority party leader, and coalition government Minister, Rodney Hide, requested full details of all data, code, etc from climate minister, Dr. Nick Smith. You can see the full letter at local blog site http://whaleoil.gotcha.co.nz/. Acknowledgement to local blogger, Whaleoil for this post.
Rodney Hide is not a man who is easily fobbed off. He is well known for his effective ‘crusading’ skills. He is also well educated and very articulate. Now that this request is in the public domain it will not easily be dismissed.

Mike S

I guess all the other sites were moved up in elevation as well.
Yeah. That’s the ticket.
They were all moved.

Wratts Up With That?

Seth

I know this is a little OT but I’m really worried.
Has anybody noticed google has removed any search suggestions relating to the AGW scandal? I actually noticed this today because I now have to type in my entire search string. I found someone who actually posted on this.
http://www.smalldeadanimals.com/archives/012721.html
This has me very worried given googles massive control over information flow.

Jason

“The Kelburn site is on average 0.8°C cooler”
Where is the science and data for that? Where are the “peer reviewed” papers?
“internationally accepted techniques”
Likely errant code for “CRU and everyone else on the warming dole.” Have these “techniques” or tricks been revealed in “peer reviewed” papers/

LilacWine

They had to move it up the hill. They were predicting a 122m rise in sea levels. 😉

David L. Hagen

Mounting anemometers on buildings would also appear to distort the results. See:
Modelling of the Performance of a Building-Mounted Ducted Wind Turbine S J Watson, D G Infield, J P Barton and S J Wylie, Journal of Physics: Conference Series 75 (2007) 012001 doi:10.1088/1742-6596/75/1/012001

brnn8r

In New Zealand we have a version of the FOIA it’s called the official information act 1982
http://www.legislation.govt.nz/act/public/1982/0156/latest/DLM64785.html
Would it be worthwhile me testing the waters to see if I can get the data released under the act?

Jason

“Correct me if I’m wrong here, but wouldn’t more thermometers actually give a more accurate reading of what is happening?”
All the science and scientist nervousness indicates straight readings of thermometer records do not give them the warming they want. Thus the resort to adjustments, treemometers and other supposed proxies for temperature change.

Socratease

To believe NIWA’s excuse of correcting for measurement station movement, you’d have to believe that it was just an amazing coincidence that all the stations moved in just such a way over the decades so as to cancel out all the warming that was simultaneously taking place and leave an amazingly flat record in the uncorrected raw data.
Yeah, that’s the ticket.

The Other Pamela Gray

Hi Ya Viv!
Thanks to ClimateGate, we now all know what these ‘internationally accepted techniques’ look like, and we all know what ‘internationally accepted’ stands for.
Lying in order to get trillions in grant money and rule the world has been an international standard since Biblical times.

brnn8r

Wiki has an overview here: http://en.wikipedia.org/wiki/Official_Information_Act_1982
Although I’ve become a bit suspect of Wiki recently.
So Dr Wratt has mentioned the changes in Wellington (Where I live) what about the rest of New Zealand?

Arnold

Just call me stupid, but one thing i dont understand that if station no1 and 3 are equal (words of niwa) and you would leave out station 2 (just fill in 999 for every measurement 🙂 ) then you would see no warming. In stead they made the adjustments like a upward sloping line.

In addition to the ‘weather geek’ station surveys (visible & IR photos, Lat/Lon/Altitude, interviews and such), I think it prudent to start asking about temperature sensor calibration. How frequently calibrated? Gain & offset values vs time? Method of calibration (e.g. ice-bath & boiling water method)? External test equipment used in the calibration? Calibration of the External Test Equipment (as we in the colonies call ‘NIST Traceability’ … I should be able to construct a paper-trail from the 1-deg C measured here in Arizona all the way back to the NIST 1-deg C in Washington DC, etc)

Ray

Oh! I though that the Internationally accepted technique to adjust temperatures was to use tree rings and readjust the temperature of real thermometers. So, what they really should have done is cut a tree at Kelburn and another at Thorndon and do the Mann trick… Et Voila!

John M

So does this mean there was no TOBS correction?

Andrew

There is a lot more to go on this story yet. On 27/11/09 Minority party leader, and coalition government Minister, Rodney Hide, requested full details of all data, code, etc from climate minister, Dr. Nick Smith. You can see the full letter at local blog site http://whaleoil.gotcha.co.nz/. Acknowledgement to local blogger, Whaleoil for this post.
Rodney Hide is not a man who is easily fobbed off. He is well known for his effective ‘crusading’ skills. He is also well educated and very articulate. Now that this request is in the public domain it will not easily be dismissed.

Rodney Hide is also scientifically trained. He has a bachelor degree in zoology and a masters (MSc) in resource management.
http://www.parliament.nz/en-NZ/MPP/MPs/MPs/7/6/1/49MP11981-Hide-Rodney.htm

Glenn

“The Kelburn site is on average 0.8°C cooler than Thorndon, because of the extra height above sea level.”
This isn’t science. There is no “average” based solely on altitude, an average of locations within an air column in a specified time span would not necessarily be the same average of those same points in a different time span. Especially with accuracies and concerns are considered in increments of tenths of a degree, this is pseudoscience, no better than guessing.
Why not just have one station for the world, and determine temperatures for every location on the earth, by an average lapse rate! Were there only one, “the best we could do” would not make it scientific or reality. This adjustment stuff can only be carried so far.

There is in fact a perfectly standard way to handle this problem. Use a third station which overlaps both the old and new stations, and adjust the old so it has the same difference from the third station as the new.
Doing it in this order may not at first seem logical but it avoids having to continuously adjust the new station.
Given that long-term relative temperatures do not vary much over distances of 10s, or even 100 of kms, this method is perfectly sound. If the distance is of the order of 100s of km then it should be done separately for each calendar month.