Guest Post by Willis Eschenbach
[see Update at the end of this post]
I got to thinking about the (non) adjustment of the GISS temperature data for the Urban Heat Island effect, and it reminded me that I had once looked briefly at Anchorage, Alaska in that regard. So I thought I’d take a fresh look. I used the GISS (NASA) temperature data available here.
Given my experience with the Darwin, Australia records, I looked at the “homogenization adjustment”. According to GISS:
The goal of the homogenization effort is to avoid any impact (warming or cooling) of the changing environment that some stations experienced by changing the long term trend of any non-rural station to match the long term trend of their rural neighbors, while retaining the short term monthly and annual variations.
Here’s how the Anchorage data has been homogenized. Figure 1 shows the difference between the Anchorage data before and after homogenization:
Figure 1. Homogenization adjustments made by GISS to the Anchorage, Alaska urban temperature record (red stepped line, left scale) and Anchorage population (orange curve, right scale)
Now, I suppose that this is vaguely reasonable. At least it is in the right direction, reducing the apparent warming. I say “vaguely reasonable” because this adjustment is supposed to take care of “UHI”, the Urban Heat Island effect. As most everyone has experienced driving into any city, the city is usually warmer than the surrounding countryside. UHI is the result of increasing population, with the accompanying changes around the temperature station. More buildings, more roads, more cars, more parking lots, all of these raise the temperature, forming a heat “island” around the city. The larger the population of the city, the greater the UHI.
But here’s the problem. As Fig. 1 shows, until World War II, Anchorage was a very sleepy village of a few thousand. Since then the population has skyrocketed. But the homogeneity adjustment does not match this in any sense. The homogeneity adjustment is a straight line (albeit one with steps …why steps? … but I digress). The adjustment starts way back in 1926 … why would the 1926 Anchorage temperature need any adjustment at all? And how does this adjust for UHI?
Intrigued by this oddity, I looked at the nearest rural station, which is Matanuska. It is only about 35 miles (60 km) from Anchorage, as shown in Figure 2.
Figure 2. Anchorage (urban) and Matanuska (rural) temperature stations.
Matanuska is clearly in the same climatological zone as Anchorage. This is verified by the correlation between the two records, which is about 0.9. So it would be one of the nearby rural stations used to homogenize Anchorage.
Now, according to GISS the homogeneity adjustments are designed to adjust the urban stations like Anchorage so that they more closely match the rural stations like Matanuska. Imagine my surprise when I calculated the homogeneity adjustment to Matanuska, shown in Figure 3.
Figure 3. Homogenization adjustments made by GISS to the Matanuska, Alaska rural temperature record.
Say what? What could possibly justify that kind of adjustment, seven tenths of a degree? The early part of the record is adjusted to show less warming. Then from 1973 to 1989, Matanuska is adjusted to warm at a feverish rate of 4.4 degrees per century … but Matanuska is a RURAL station. Since GISS says that the homogenization effort is designed to change the “long term trend of any non-rural station to match the long term trend of their rural neighbors”, why is Matanuska being adjusted at all?
Not sure what I can say about that, except that I don’t understand it in the slightest. My guess is that what has happened is that a faulty computer program has been applied to fudge the record of every temperature station on the planet. The results have then been used without the slightest attempt at quality control.
Yes, I know it’s a big job to look at thousands of stations to see what the computer program has done to each and every one of them … but if you are not willing to make sure that your hotrod whizbang computer program actually works for each and every station, you should not be in charge of homogenizing milk, much less temperatures.
The justification that is always given for these adjustments is that they must be right because the global average of the GISS adjusted dataset (roughly) matches the GHCN adjusted dataset, which (roughly) matches the CRU adjusted dataset.
Sorry, I don’t find that convincing in the slightest. All three have been shown to have errors. All that shows is that their errors roughly match, which is meaningless. We need to throw all of these “adjusted datasets” in the trash can and start over.
As the Romans used to say “falsus in unum, falsus in omnibus”, which means “false in one thing, false in everything”. Do we know that everything is false? Absolutely not … but given egregious oddities like this one, we have absolutely no reason to believe that they are true either.
Since people are asking us to bet billions on this dataset, we need more than a “well, it’s kinda like the other datasets that contain known errors” to justify their calculations. NASA is not doing the job we are paying them to do. Why should citizen scientists like myself have to dig out these oddities? The adjustments for each station should be published and graphed. Every single change in the data should be explained and justified. The computer code should be published and verified.
Until they get off their dead … … armchairs and do the work they are paid to do, we can place no credence in their claims of temperature changes. They may be right … but given their egregious errors, we have no reason to believe that, and certainly no reason to spend billions of dollars based on their claims.
[Update – Alaska Climate Research Center releases new figures]
I have mentioned the effect of the Pacific Decadal Oscillation (PDO) below. The Alaska Climate Research Center have just released their update to the Alaska data. Here’s that information:
Figure 4. Alaska Temperature Average from First Order Observing Stations
In the Alaska Climate Research Center data, you can clearly see the 1976 shift of the PDO from the cool to the warm phase, and the recent return to the cool phase. Unsurprisingly, the rise in the Alaska temperatures (typically shown with a continuously rising straight trend line through all the data) have been cited over and over as “proof” that the Arctic is warming. However, the reality is a fairly constant temperature from 1949-1975, a huge step change 1975-1976, and a fairly constant temperature from 1976 until the recent drop. Here’s how the IPCC Fourth Assessment Report interprets these numbers …
Figure 5. How the IPCC spins the data.
SOURCE: (IPCC FAR WG1 Chapter 9, p. 695)
As you can see, they have played fast and loose with the facts. They have averaged the information into decade long blocks 1955-1965, 1965-1975, 1975-1985 etc. This totally obsures the 1975-1976 jump. It also gives a false impression of the post-1980 situation, falsely showing purported continuing warming post 1980. Finally, they have used “adjusted data” (an oxymoron if there ever was one). As you can see from Fig. 4 above, this is merely global warming propaganda. People have asked why I say the Alaska data is “fudged” … that’s a good example of why.
Richard S Courtney (11:31:44) :
Your soundbite 1 is just demonstrably false, and implausible. As I’ve said, the satellite records have been changed dramatically as corrections were being made. If the surface record people were somehow designing their adjustment algorithms to match the satellite records, don’t you think we’d have seen the same dramatic corrections in the surface record? We’ve seen absolutely nothing of the sort. The surface record trends for 1979-2003 are roughly what they were before the satellite corrections were made; it’s the satellite records that have been changed. Not the other way around. How can you continue repeating a point, when it just doesn’t match any reality?
As for the motivation of the surface adjustments: Whether they are successful or not, all the groups are trying to accomplish the same goal: a reliable record of surface temperature. They all start with pretty much the same data (CRU uses some extra data over GISS or NOAA/NCDC and probably JMA), and then apply different methods, as they have honest disagreements over what are the best methods to use. But all of the methods are clearly described, for GISS and GHCN at least. GISS is concerned by urban warming, so it uses the somewhat crude method described in this thread to get rid of it. That’s the only adjustment GISS uses. It’s clearly motivated by trying to get rid of urban effects. So why would you characterise it as merely some sort of fudge to match GHCN or the satellites or whatever?
Since GISS and GHCN start with the same data, they don’t need to fudge anything if all they wanted was for their results to match each other. They could simply just use the same methods, and then have the same results.
Soundbite 2, part 1 is a corollary to Soundbite 1; since I don’t think Soundbite 1 made any sense, I’ll neglect it.
Soundbite 2, part 2: The different people involved prefer their methods over the others; that’s why they use different methods. You can read discussions of this in the papers they’ve written. As for calibration, I don’t know what you’re getting at. What is there to calibrate against?
It’ll actually be interesting to watch this, going forwards. The difference between the CRU and GISS results is pretty much entirely in the Arctic. Will one group decide to change how they handle the Arctic, or will they both persist in thinking their way is better? Also, the GHCN is coming out with an entirely new adjustment method; we’ll see how that is received.
Soundbite 3: The satellite records are part of your substantive point, inasmuch as you have one. And they clearly show that your thinking is confused.
Soundbite 4: It depends on what adjustment you are talking about. If GISS corrects Anchorage because Anchorage had urban warming, well the adjusted record is actually not indicative of what actually happened in Anchorage. They took out the urban warming, but the urban warming was real.
On the other hand, if there is a station move in 1962 at some station, resulting in a big discontinuity at that station, then the raw data clearly have an artifact that doesn’t reflect the local climate. So you’d want to use GHCN adjusted data, which is designed to remove the effect of such things.
carrot eater (12:44:20) :
You say to me:
“Your soundbite 1 is just demonstrably false, and implausible.”
Say what?
Demonstrably false? Absolutely not, and you do not demonstrate it is “false”. Please remember that this began (and I have repeatedly reminded you) as my response to a question to you that you have avoided from Willis at (15:29:36).
That question was;
“What I don’t understand is how this is all justified. I keep asking for a reason that anyone would start adjusting a pristine rural record in 1920. Do you or GISS have the slightest scrap of evidence that there was something wrong with the record?”
I replied saying at (07:27:23) :
“The adjustments are not intended to correct individual station records because it is thought “there was something wrong with the record”. And I think you have been side-tracked by arguments (e.g. from carrot eater and Nick Stokes) that the adjustments may be making correct adjustments in individual cases.
I think I know why the adjustments are universally applied by computer algorithm acting on each data set from each station record. And it is not relevant to the purpose of the adjustments whether or not the adjustments can be justified for any individual station record.”
Snip
“Such adjustment [to get MGT data sets] “to agree with each other” provides a complete explanation for why “anyone would start adjusting a pristine rural record in 1920”.”
You have provided
(a)
no explanation for why “anyone would start adjusting a pristine rural record in 1920”
and
(b)
no explanation for why my explanation (that fits the facts) is wrong.
Instead you have obfuscated, ignored specific questions, and attempted to side-track discussion from consideration of the surface records to consideration of the satellite records (an obvious attempt at red-herring).
Of course there is little alteration to recent surface station data sets: they (almost) agree with the satelliite data. As I said (repeatedly);
“It should also be noted that there is no possible calibration for the estimates of MGT.
The data sets keep changing for unknown (and unpublished) reasons although there is no obvious reason to change a datum for MGT that is for decades in the past. It seems that – in the absence of any possibility of calibration – the compilers of the data sets adjust their data in attempts to agree with each other. Furthermore, they seem to adjust their recent data (i.e. since 1979) to agree with the truly global measurements of MGT obtained using measurements obtained using microwave sounding units (MSU) mounted on orbital satellites since 1979. This adjustment to agree with the MSU data may contribute to the fact that the Jones et al., GISS and GHCN data sets each show no statistically significant rise in MGT since 1995 (i.e. for the last 15 years). However, the Jones et al., GISS and GHCN data sets keep lowering their MGT values for temperatures decades ago.”
The important point is that
THEY KEEP LOWERING THEIR MGT VALUES FOR TEMPERATURES DECADES AGO.
I could address each of your statements in your post at (12:44:20) but there is no point because you ignore what I write and obfuscate the issue. This is clearly demonstrated by your asking me:
“What is there to calibrate against?”
I answer: NOTHING!
That is my point that I have made to you over and over again and yet again in this post. I fail to understand how you cannot comprehend the meaning of my sentence which I have repeated ad nauseum that says;
“It should also be noted that there is no possible calibration for the estimates of MGT.”
Indeed, it is a central point of my argument. The compilers of the MGT data sets have nothing against which to calibrate the results of their work. Therefore, the only way they can obtain ‘confidence’ in the results their work is by increasing the agreements between the results of their compilations. And the continuing changes they make to their methods indicate that this is what they are doing.
If you were defending science then you would have attempted to answer one of the questions I have repeatedly put to you; viz.
“Why does each of the teams compiling the MGT data sets not try to justify its method as being the right one that should be used as THE reference in the absence of a true calibration?”
In conclusion, my argument is clear and ad hominem assertion that my “thinking is confused” does not change that.
My argument answers the question from Willis that you have avoided. You have not addressed that question despite my repeated requests provided to you in several different ways. Instead, all your responses to me have have obfuscated, ignored specific questions, and attempted to side-track discussion with a red-herring.
So, I give up. Take ‘the last word’ if you want. Onlookers can assess this discussion for themselves.
Richard
I show you that in no way are the surface records being intentionally adjusted to try to converge with the satellite data. The idea is just implausible on the face of it.
You accuse me of bringing up a red herring.
And yet, then you repeat, “Furthermore, they seem to adjust their recent data (i.e. since 1979) to agree with the truly global measurements of MGT obtained using measurements obtained using microwave sounding units (MSU) mounted on orbital satellites since 1979. This adjustment to agree with the MSU data”
How can you tell me I’m side-tracking from your questions, when I’m addressing what appears to be a central point of your thesis, seeing as you continue repeating it?
“You have provided
(a)
no explanation for why “anyone would start adjusting a pristine rural record in 1920””
Have you read the discussion here? This station shows up as being well-lit at night. By the GISS method, it is then automatically considered possibly urban. GISS doesn’t bother trying to figure out exactly when something became possibly urban; they just treat the entire history of the station as being suspect. After all, the strongest urban trend will likely be during the period when something went from rural to urban. So they basically toss the station out. The method is clearly described; the code is publicly available.
You can agree or disagree with the use of satellite light data to decide if something is urban or not, but you can’t claim that the adjustment here is not transparent. It’s perfectly objective; no human interaction involved. If you take the time to read the descriptions, you’ll understand perfectly well why the program did what it did, even if you think the program is not implementing a very good method.
And again, GHCN and GISS start with the same raw data. Why on earth would they have to fudge to get the same result? They’re starting at the same place. And the trends are about the same, in both raw and adjusted data. So if they’re fudging to get some desired trend, they certainly aren’t trying very hard.
Richard S Courtney (11:33:41) :
Phil. (10:53:09) :
I still demand a retraction of your untrue and odious libel. Also, I would like to know if your family name is Jones.
Demand all you like it isn’t happening. CE and I have pointed out the errors in your argument, it’s completely at odds with the facts, and as regards the UAH is totally at variance with the history of that measurement.
It is unlikely that anyone lacking a vested interest is still reading this discussion. But, in case there are, I draw attention to the item by Edward R. Long at
http://www.americanthinker.com/2010/02/a_pending_american_temperature.html
It concludes;
“That is, the NCDC’s treatment has forced the rural value to look more like that of the urban. This is the exact opposite of any rational consideration, given the growth of the sizes of and activities within urban locations, unless deception is the goal.”
But Long is discussing how the data has been massaged, and – as this discussion demonstrates – there are those whose vested interests cause them to defend the indefensible while hiding behind anonymity.
Richard
It seems the link in my above post has not appeared in entirety. Here it is again
http://www.americanthinker.com/2010/02/a_pending_american_temperature.html
I hope it has worked this time.
Richard
Richard S Courtney (02:11:05) :
– as this discussion demonstrates – there are those whose vested interests cause them to defend the indefensible while hiding behind anonymity.
This ad hominem illustrates your approach of making it up as you go along, you have absolutely no evidence for this statement, just like you had no evidence for your statement about adjustments.
You can have your analysis picking out 48 US stations, if you want.
How about using all of them?
Comparison of all GHCN data, raw vs adjusted:
Under Q4: http://www.ncdc.noaa.gov/cmb-faq/temperature-monitoring.html
Comparison of GHCN raw data, vs GISS adjusted, for the Northern Hemisphere:
http://tamino.wordpress.com/2010/02/25/false-claims-proven-false/
Preliminary comparison of weather station raw data (continuous records only), vs CRU adjusted, Northern Hemisphere land:
http://www.drroyspencer.com/2010/02/new-work-on-the-recent-warming-of-northern-hemispheric-land-areas/
Again and again, your contention that adjustments are being done to achieve some nefarious goal are just wrong. When you look globally or hemispherically, the effect of adjustments is quite minor. Even if it wasn’t minor, that wouldn’t be proof that the adjustments are bad, but as it is, the effect is minor.
Phil. (05:37:24) :
You say:
Richard S Courtney (02:11:05) :
– as this discussion demonstrates – there are those whose vested interests cause them to defend the indefensible while hiding behind anonymity.
This ad hominem illustrates your approach of making it up as you go along, you have absolutely no evidence for this statement, just like you had no evidence for your statement about adjustments.
*********
So your posting libels here under the title “Phil” is not acting anonymously?
And if you have no vested interest then why have you posted – and refused to retract – an untrue libel behind that anonymity?
Why should anybody afford any respect to the comments of the person (?) who hides behind the pseudonym of ‘carrot eater’ when
(a) he claims “the effect of adjustments is quite minor”,
(b) but provides no explanation for why corrupting the data with the adjustments is defencible,
(c) while trying to deflect discussion onto consideration of other data sets (i.e. UAH and NSU) instead of those that have the “adjustments” applied?
The two of you can continue your defence of the indefecible while hiding behind anonymity if you choose. But the BS meter of any non-partisan onlookers will be sounding a very loud alarm.
Richard
Richard S Courtney (08:16:39) :
“(a) he claims “the effect of adjustments is quite minor”,”
Look at the graphics. They speak for themselves. Global raw, global adjusted. Northern Hemisphere raw, northern hemisphere adjusted. and then NH, again. They quite clearly show that you are wrong, and that your claims are untenable.
Again, if the raw and adjusted trends were a little different from each other, that wouldn’t be proof of any wrongdoing, so long as the adjustments were justifiable. But currently, the raw and adjusted trends are the same, anyway.
“(b) but provides no explanation for why corrupting the data with the adjustments is defencible,”
The specific adjustments shown in this post have been explained time and again.
“(c) while trying to deflect discussion onto consideration of other data sets (i.e. UAH and NSU) instead of those that have the “adjustments” applied?”
You’re the one who brought up a claim about the relationship between surface and satellite data. You continue bringing it up. It appears to be a central part of your reasoning. And somehow I’m wrong for discussing your claim, and showing that it’s baseless?
Phil. (05:37:24) :
You say:
Richard S Courtney (02:11:05) :
– as this discussion demonstrates – there are those whose vested interests cause them to defend the indefensible while hiding behind anonymity.
This ad hominem illustrates your approach of making it up as you go along, you have absolutely no evidence for this statement, just like you had no evidence for your statement about adjustments.
*********
So your posting libels here under the title “Phil” is not acting anonymously?
That is my name, just like Richard S Courtney is yours, are you the one who is the Prof. at Kutztown, or the one who is a technical editor for CoalTrans International, ….
And if you have no vested interest then why have you posted – and refused to retract – an untrue libel behind that anonymity?
I don’t have to have a ‘vested interest’ in order to post, and the statement you refer to is not untrue.
I thought the homogeneity adjustment was the averaging over a 1200-2400km radius. A sort of spatial smoothing.
I understood airports are often used as the “rural” reference.
I suspect that too much focus on individual stations clouds the real issue of disclosure of the raw data and disclosure of the coded algorithms for adjustment to permit others to scrutinize and attempt to repeat the analysis.
Phil. (13:09:52)
BZZZZT. Next contestant please, I’m sorry sir, that’s the wrong answer. Jennifer, what kind of prize do we have tonight for our unlucky contestants? …
Google “Richard S. Courtney”, and the first nine entries are about the Richard Courtney who is posting here. Pretending that he is posting anonymously, as you assuredly are, is absolute nonsense. He and I both have the balls to put our true names on our opinions. I can only wish that you had the same.
I have updated the head post with some new information. My thanks to all who have posted, whether agreeing or disagreeing. This is the best of science, keep’m coming …
Regards,
w.
The two of you can continue your defence of the indefecible while hiding behind anonymity if you choose. But the BS meter of any non-partisan onlookers will be sounding a very loud alarm.
No, I’m an entirely random reader, and having waded through this lot I find that carrot-eater consistently provides good information and sensible explanations, whilst you repeat assertions which have been answered whilst claiming that they have not and generally bluster in a very tiresome way. Whilst it would be nice to know who Carrot-Eater is, so that due credit could be given, his use of an alias does no harm to his (her?) cogent argument.
I have learned a great deal about how the temp record is constructed and adjusted from this page.