Wednesday, January 27, 2010

Warming in NZ, if you want

Below is the graph used by NIWA to show how we are supposedly warming. It is base on a composite of 7 sites around NZ dating back to the 1850's. The "anomaly" is really just the actual temperature recording less the average temperature for 1971-2000. I'm not sure why they have chosen this range to arrive at an average temperature, but it has the definite effect of making the trend look greater.
Using their raw data, I just calculated the anomaly using the the average temperature from 1860 to the present, instead of 1971-2000.(allowing for the fact that several of the sites are not complete records) My graph shows the resultant anomaly in green compared with the NIWA result in red.
I'll leave you to your own conclusions, but to me the green line show nothing remarkable about our temperature apart from a slight warming around 1950 till about 2000. And the convenient fact that you can manipulate the data to paint any picture you want.

28 comments:

Anonymous said...

Ah, care to run that by me again?
all using the 1971-2000 average does is give a baseline temperature to compare the temperature over the entire period from which data is used, it wouldn't make any difference to the slope if the baseline used was 1900-1930, the difference would be that the baseline would be at a lower temperature (because the average temp between 1900-1930 was lower that the average temp between 1971-2000.

Andrew W

Anonymous said...

Lou, you need to read page 68 on in this
http://scienceandpublicpolicy.org/images/stories/papers/originals/surface_temp.pdf

sorts out Andrew W(anker) nicely

Andrew- can you share the algorythm NIWA used to make the adjustments?
Also do you think NIWA having a Temp Station on top of their building is a solid and perfect scientific way of gathering accurate temperatures?
Yep Global Warming is man made alright. Made by Jim Salinger with help from Harry_read_ me
hahahahaha

Anonymous said...

Thanks Andrew W
My point was that you can manipulate data however you want. I'm no scientist but as as many climate scientists appear to have sold their science to the highest bidder then my graph has as much relevence to the NIWA one.It also doesn't explain why NIWA treated some of the data differently to the rest to heat up the recent years.
I also posted this just to see how long it would take for you to comment.
Lou

Anonymous said...

Hi Lou, does that mean that you acknowledge that the difference between the slope of your graph and the NIWA graph isn't just down to changing the baseline period?

How Niwa adjust the raw data to correct for changes in the data collection is something for those expect in that sort of thing to scrutinize, as long as the process is open I've confidence that the final adjusted result will be fair.

Andrew W

Anonymous said...

"How Niwa adjust the raw data to correct for changes in the data collection is something for those expect in that sort of thing to scrutinize, as long as the process is open"

Oh, I see. Then since you dont know, your belief is based on faith and faith alone!
How appropriate for a religion.
Gee, it would be nice if they told us or at least "other" experts. But they dont.

barry said...

Yes - in the last few months since the hockey stick started to splinter Ive been looking a bit more at this area and theres only one thing that I am sure of - whatever global worming there is is definitely man - made.
By making the data say whatever man wants it to.

As far as i can make out, the weather stations are up to 5C off-true (due to sitting and changes), and the margin of error is thus much more than the claimed rise.

Im getting the feeling that its Y2K, Bird Flu, etc all over again and Ive started turning all the lights on again.

Anonymous said...

Each of us relies on experts doing their jobs properly every day Anonymous, It's more a trust in the system than blind faith, the scientific system - like other systems that work - does so because of openness. When climate scientists aren't being open the criticism is probably justified.

Barry demonstrates "faith" in that he's decided to follow beliefs that aren't extensively scrutinized in a formal manner, he's chosen to go with the voodoo doctors who's claims always fail when tested, rather than those practicing scrutinized scientific methods.

Andrew W

Anonymous said...

Ummmm, Lou, you seem to have promulgated 'damned lies' - inadvertently, I'm sure ;)

As Andrew W said, the scientists normalise the data (in this case, by subtracting all temperatures from a chosen base period of 1970-2000). This normalisation just allows the variation in the long-term data to be contrasted with data from recent times - it does not change the *relative* differences in annual temperatures.

The base period is chosen to be a recent time (roughly the time period over which climate change has been an issue, and limited actions taken to mitigate it). This highlights any long-term change from the base period temperatures (in this case, earlier temperatures were cooler).

Using a wider base period - as you did - does exactly the same thing as NIWA has done, but by using a longer base period (averaging over all the years 1850-2000), the average is closer to the data over the whole period, so the trend line has a lower slope.

That is to be expected - but what is important is that even your green curve shows a trend upwards in temperature, so global warming is real. Your slope may be less dramatic, but it tells the same story as the NIWA slope.

Similarly, if you used just 1990-2000 as a base period, the trend slope would be even steeper - try it! The graph is just there to show a seperation between a long-term trend upwards in temperatures, and annual (natural) variations in temperature.

Aaah, statistics. Gotta luv 'em. Did I mention that your graph shows global warming is real? hehe

Anonymous said...

Anon 9.48
Of course its real. The earth warms and the earth cools.There have been lots of periods like that.But it isnt warming by 2-6 degrees as the fraudulent liars at the IPCC would have us believe. More like .3 per century which is in line with warming from the end of the Little Ice Age. Man has nothing to do with it.
"normalise the data" Ha, you mean take the raw original data and change it to suit the agenda!!!
Anybody who believes the manipulated figures from the land based Temp Stations has their heads in the sand. Every month Spencers figures prove them wrong.
Fucking dumbass

Anonymous said...

Fucking dumbass
January 29, 2010 7:36 AM

Global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) between the start and the end of the 20th century, which is warming at a rate far higher than that previously.

Andrew W

Anonymous said...

Andrew W
So you admit 2-6 degrees is wrong and the Hockey Stick is incorrect?
Personally I'm becoming very dubious about the early measurements. Did you read the Surface Stations Org research?
Dr Roy Spencer claims .28 for the last 30 years.Have you heard of him?

Ken said...

Lou said "And the convenient fact that you can manipulate the data to paint any picture you want."

Which is of course true - but is it honest? Of course not.

The fact remains that there will be an objective relationship between temperature and time and we should use the procedure for treating the data which gives the best estimate of this.

Now the problem with your post (compared with the normal output of scientists) is that there is no description of how you treated the data. We cannot check you out as we can with a scientists who has published a paper with methodology included.

For example - what do you mean by "Using their raw data, I just calculated the anomaly using the the average temperature from 1860 to the present, instead of 1971-2000."? Taken at face value this seems to be committing the same mistake as that used by the "Climate Science Coalition" in their discredited report. Assuming one can just throw data from different sites together without adjusting for site effects.

As the NIWA reference states: "Failing to adjust data to account for major site changes is bad science. "

Short of attempting to duplicate what you have done there is no way of checking your analysis.

Perhaps you could start by telling us how, or if, you took major site changes into account?

Lou Taylor said...

Thanks Ken
I don't pretend to be a scientist I just played around with the niwa spreadsheet and put a graph on a political blog.
I know that the underlying trend of the graph will not change regardless of the chosen average.

I have no doubt that the climate is changing but I am far from convinced that it is caused by man or even CO2. The earth's climate has experienced huge variations in temperatures and CO2 levels in the past and has proved to be an extremely resiliant system. The light warming this century is as much a good thing as a bad thing. Mankind has always prospered when it has been warmer. And plants like CO2.
I am only saddened by the fact that it seems many scientists have lied and cheated to support a particular political agenda.

Ken said...

Lou - you say "I don't pretend to be a scientist I just played around with the niwa spreadsheet and put a graph on a political blog.
I know that the underlying trend of the graph will not change regardless of the chosen average."


The problem is that in "playing around" with the spreadsheet I think you have made a big mistake and produced a misleading, false, result.

In fact, if you do the work properly your claim that "any picture you want" can be produced is just wrong.

I have had a look at the spreadsheet and think your mistake was to arbitrary combine data for the whole 1853-2008 ignoring the fact that data just doesn't exist for most of the stations for a lot of that time.

You have, I think, taken the 7-station composite and ignored how this was derived (it's not an average). As it was derived using the 1971-2000 data it is just not appropriate to take "the average temperature from 1860 to the present, instead of 1971-2000." There can be no such thing as an average when there just isn't data for some of the stations.

It is shocking for you to say "I am only saddened by the fact that it seems many scientists have lied and cheated to support a particular political agenda" when you have no evidence of it. In fact one could say you yourself have distorted the data to fit your own political agenda.

I think a bit of humility is in order. Don't just assume our NIWA scientists have lied. Try to understand how the data was used. What adjustments and procedures were used, and in fact required. Recognise that perhaps, as they are the professionals, have long training and experience in their field, they might understand better how to combine data like this.

I guess this is the problem of making data available as NIWA has done. People will use it incorrectly, or manipulate it to produce results fitting their own agenda. Surely the most appropriate reaction when you get a result like this is to acknowledge that perhaps you are the mistaken one and to investigate it further.

Anonymous said...

"Now the problem with your post (compared with the normal output of scientists) is that there is no description of how you treated the data. We cannot check you out as we can with a scientists who has published a paper with methodology included."

Ken
Please provide a link to "those Scientists" who have published the algorithms they have used in their data changes. Peer reviewed only please.NIWA s stuff would be a good start.

Lou Taylor said...
This comment has been removed by the author.
Lou Taylor said...

Thanks Ken
I freely admit that my graph was a load of crap. Apart from the fact that I have no idea how niwa arrived at the figures in their spreadsheet in the first place.

Very much in the same vein of the IPCC hockeystick.

That was the whole point.
Climate change has been put in the
"if you can't beat them with science, baffle them with bullshit" basket.

Lou Taylor said...

I fogot to add Ken that I didn't say specifically that niwa scientist have lied. Only time will tell.
But there is ample evidence to suggest that climate scientists have been less than truthful with the facts.

Ken said...

But Lou - what is the "ample evidence to suggest that climate scientists have been less than truthful with the facts?"

We have seen a lot of spin on emails taken out of context and the mistake with the 2035 glacier date. But my reading of the IPCC documents is that they are very balanced, conservative and understated.

You "have no idea how niwa arrived at the figures in their spreadsheet in the first place." Well get off your bum and find out. At least the honest thing is to do this before criticising or distorting their data.

As for the "hockey stick" - this is surely an example of the deniers trying to baffle with bullshit. And they seem to succeed with some people. But you could again look at the facts about this (eg. Climate change deniers’ tawdry manipulation of “hockey sticks”).

"I freely admit that my graph was a load of crap. " - Then why the hell publish it? And why make such outrageous claims against our NIWA scientists and others? You are implying that NIWA's graph is crap - but done exactly nothing to show that.

"if you can't beat them with science, baffle them with bullshit" basket." - isn't this what you have done here? Admitted as crap?

Granted that most people can't understand the science of this - the same as I can't understand how my car works. I take it to a good mechanic. Our government takes these climate issues to good scientists.

Just imagine loudmouths shouting at me that my mechanic has got it all wrong. That the situation is exactly the opposite! What should a sensible person do in that case? Listen to the expert or the loudmouth?

Lou Taylor said...

Jeez Ken
Don't take it all so personally. This is a political blog.
I've just seen millions of dollars of taxpayers money spent on a problem which may not even exist based on science which may or may not be right.
If you are absolutely convinced of man made global warming then good luck to you. I suggest you buy carbon credits and retire a wealthy man.

Simon Arnold said...

From the occasional looks I’ve had at various temperature series in NZ it does seem to me that the complexity gets glossed over – leading to interminable “they did, no they didn’t” discussions.

Just in terms of this data set some questions to ponder:

What do we mean when we talk about the temperature in NZ? I guess we instinctively think of the average surface temperature across the land mass or some such. But what we are looking at here is the temperature at seven stations with a strong urban, low altitude and coastal bias. They aren’t a representative sample of the land mass so should we refer to this as NZ’s temperature?

What should we do about missing data? Here in the case of the anomalies we just ignore them. So at the beginning of the series we are just measuring Dunedin. If we deliberately choose these seven because they are representative in some way shouldn’t we just limit the time series to the period from 1908 when we have a complete series of seven recording stations?

Why are average temperatures in years with scare data reconstructed from 1971-2000 averages? Aren’t we better off knowing the limitations of the data (i.e. there were no recordings) than introduce unnecessary bias into the record?

If we use anomalies to normalise the temperatures before averaging them, why don’t we normalise the standard deviations?

If we are going to use statistical techniques to put a time series through the average anomalies to demonstrate a warming trend, why do we use deterministic models to adjust for changes at recording sites that will artifically reduce the variability of the data and introduce systemic bias and false accuracy into the subsequent time series analysis?

I'm sure if I knew more there would be other questions :)

Ken said...

Lou, I don't take it personally and I am already retired.

And I admit to not understanding "carbon credits."

But why the hell should a political blogger pretend to "discover" something which eludes the experts?

Only because it advances their politics, I suggest.

Mind you, publishing a post with claims like this does sort of discredit you in the political as well as the scientific sphere, doesn't it.

Lou Taylor said...

I was only pointing out the fact that we have been fed a lot of so called science in the name of global warming. That science has lost much of it's credibility lately.
But when I post a graph showing the same results in a different way scientists like yourself get all upset at the result. If scientists want to give it then they should take it too.
I welcome the news that niwa are making everything available on line.
As for politics I don't belong to any party and just blog to express my opinion on things.

As for your mechanic anology.
If one mechanic tells me I need to spend $2000 on my gearbox, I would go and get a second opinion.Why should some climate scientists/political organisation think they can ram their point of view down people's throats and not expect to have it questioned.

Ken said...

Lou - the point is the results were not the same. You had made a mistake in their calculation.

Sure you might get a second professional opinion from another mechanic. But if you are wise you don't listen to the critical loudmouth on the sidelines.

Governments are the same. A loudmouth like Momckton is not a second professional opinion. Wheras the IPCC, with the involvement of our scientists - thousands of second opinions - reviews and summarises the scientific findings. It produces the best scientific assessment.

No wonder goverments listen to them and not the loudmouths who are clearly ignoring and distorting the science. Just as you did with the NIWA data.

Gooner said...

No wonder goverments listen to them...

Ken, more like they listen to the governments who have paid them billions over the last few years to produce results that has just led to more money for the scientists - my money.

Anonymous said...

You're thinking like a lawyer Gooner, I can believe some confirmation bias around the edges but outside of that scientists are fascinated by the physical world, they just want to understand it better, and you don't understand it better by faking results, or spinning things to create a misleading impression, that's a lawyers job.

Andrew W

Lou Taylor said...

For most science what you say is true Andrew but the science of global warming is a bit different. Simply put everybody has and is entitled to an opinion. Everyone knows that there have been massive temperature changes in the past and I for one am not convinced that what we are seeing now isn't just a continuation of natural trends. If we are warming then I would rather spend my time adjusting to the change than trying to stop it. The term "pissing in the wind" comes to mind.
I believe that the science that you hold so dearly can provide ample solutions to whatever problems mankind faces in the future. Adaption with technology.
The problem with the UN/Gore/IPCC approach is that they are attacking the "problem" from the wrong end.

Ken said...

Lou, I think you have mixed things up. The IPCC has responsibility for the sciece. It dies not advocate or make policy as this is not a job for science. It inolves ethics and politics.

You may have the opinion that current warming is natural. The scientific assessment coming out if a review of all the published evidence us that human activity most probably (90%) is an important contributo (negative as well as postive).

The IPCC has investigated both adaption andmitigation and I think it is clear that politicians must adopt both tactics, and incorporate this with sustainable development policies.

I am optimistic that humanity can deal with these problems. But as you say this willl involve scientific effort. That is why I think current attempts to discredit science won't help. It only encourages a return to superstition and hostility. That definitely won't help humanity.