Photos: NOAA's Carefree Climate Station

UPDATE: A second nearby station has been located, also showing a lower high temperature. See below.

First let me say that the Carefree, AZ Skypark airport, and the airport observer have not done anything wrong. I commend them for their service as a NOAA Cooperative Observer, a volunteer job done for the good of the country. The station was installed by NOAA/NWS Phoenix personnel and it is their responsibility for things like this difference in daytime high temperatures, such as I discovered below.

Comparison of High Temps July 8th 2010. Carefree AP is 109°F while private station 1148 meters north had a high of 104°F. Carefree AP tied the old record for that date, the only one in AZ that week, which brought attention to this station.

But after looking at the ground photos of the NOAA climate station, I have only one word to describe it: FUBAR

First some review; read my essay on what I discovered from metadata investigation of the station: A Carefree Record High Temperature in Arizona

I showed a map with all the new records plotted. But, there was a curious red dot record high temperature “anomaly” on it, 109°F in Carefree, AZ on July 8th, the only one for that entire week in the entire state.

From HAMWeather Map center - click for interactive plotter

From that essay, this image shows the station is surrounded by Asphalt tarmac:

click to enlarge imageAnd thanks to WUWT reader Glen Sheldon, we have photos from the ground (on 07/13/2010) that confirm what I suspected; the station temperature sensor is mounted directly over asphalt at roof level, both of which contribute to anomalously high temperature readings.

Looking south: Note NOAA's little "helper"

I don’t know how often the outdoor fireplace is used, but when it is, I’m sure it helps keep the cold away.

Looking west - note the asphaltic domain the sensor surveys

Looking east - more blackbody heatsinks, but you can buy a Pepsi to cool off

overall view of the Carefree, AZ station

Closeup of the MMTS - wind sheltered, next to a darker surface? Just a bit.

Seasoned volunteers have seen worse sitings, but this one has severe siting violations worth noting:

  • NOAA 100 foot rule ? – pfft!
  • Over asphalt plus physically on a building – rates a CRN5 “worst of the worst”
  • Wind sheltered on one side due to the beam – southerly wind, not so much
  • At roof level – will pick up waste heat from the building when wind blows across the flat roof
  • Incorrect height – WMO/NOAA standard is 1.5 meters – this is twice that
  • Other heat sources nearby, Pepsi machine – waste heat like an A/C unit, nearby outdoor fireplace
  • Nearby tree – listed as an obstruction in the NCDC metadata
  • Nearby automobile parking – radiator inward, under the sensor

In case anybody wonders about NOAA rooftop stations that give erroneous high temperature readings, this one should provide an excellent primer because NOAA closed it in 1999 due to similar siting problems.

How not to measure temperature, part 48. NOAA cites errors with Baltimore’s Rooftop USHCN Station

NOAA then wrote an internal technical competency manual on it advising that it is not good practice. I guess WSO Phoenix never read it.

Reference: NOAA Professional Competency Unit 6 (PCU6) manual (PDF)

But the thing that really hit me was the data they compiled, comparing to other nearby stations, and thus proving the case for rooftop bias with this station:


They cite the table with:

The table to its right summarizes a comparison of 12 months of overlapping data that was collected on the rooftop and at the new relocated site (for data continuity), relocated several blocks away at ground level with other nearby standard, ground based stations. A combination of the rooftop and downtown urban siting explain the regular occurrence of extremely warm temperatures. Compared to nearby ground-level instruments and nearby airports and surrounding COOPs, it is clear that a strong warm bias exists, partially because of the rooftop location.

Maximum and minimum temperatures are elevated, especially in the summer. The number of 80 plus minimum temperatures during the one-year of data overlap was 13 on the roof and zero at three surrounding LCD airports, the close by ground-based inner Baltimore harbor site, and all 10 COOPs in the same NCDC climate zone. Eighty-degree minimum are luckily, an extremely rare occurrence in the mid-Atlantic region at standard ground-based stations, urban or otherwise. Temperatures can be elevated on roofs due to the higher solar radiation absorption and re-radiation associated with many roof surfaces including black tar, shingles, stone, and metal. During the colder months, ongoing upward heat transfer through the roof from the heated interior of the building also can contribute to the warm bias although stronger winter winds tend to create better mixing and minimize this impact.

The table shows that the rooftop station has Tmax >90°F more than twice as often  as other stations and a Tmax >100°F  13 times where no nearby station achieved it. Similarly we have this station recording a Tmin >80°F where no other stations did.

But here we still find stations just like this in NOAA’s climate monitoring network 11 years after Baltimore’s station was closed for the same reason.

The Carefree Skypark COOP should either be closed, go to rain only, or relocated, as it is not used for airport operations, only for NOAA climate reporting. The station is polluting the climate record. NOAA needs to determine how long this has been going on and if the record is even worth keeping. I doubt it is. Also of note, this station is used to adjust other stations nearby in the “homogenization” process, further polluting the climate record.

I’m looking into doing some longer term data comparisons between the Carefree, AZ AP station and the nearby private observer station. If I’m able to obtaining the data, we’ll have a look in a future post.

Again I close with what I opened with:

The Carefree, AZ Skypark airport, and the airport observer have not done anything wrong. I commend them for their service as a NOAA Cooperative Observer, a volunteer job done for the good of the country. The station was installed by NOAA/NWS Phoenix personnel and it is their responsibility.

UPDATE: A second nearby station has been located, a MESONET station, and it’s high temperature on that day was also considerably lower, 4°F lower than the airport.

Data follows.

08 Jul 7:00 pm    93    49    22    NE    5G13    33    11%            OK

08 Jul 6:48 pm                            %    0.00        OK

08 Jul 6:45 pm    93    49    22    NE    5G15    33    8%            OK

08 Jul 6:33 pm                            %    0.00        OK

08 Jul 6:30 pm    95    49    21    E    4G14    93    20%            OK

08 Jul 6:18 pm                            %    0.00        OK

08 Jul 6:15 pm    99    45    16    E    3G08    93    17%            OK

08 Jul 6:03 pm                            %    0.00        OK

08 Jul 6:00 pm    100    42    14    SW    3G04    99    16%            OK

08 Jul 5:48 pm                            %    0.00        OK

08 Jul 5:45 pm    100    42    14    SW    3G08    99    14%            OK

08 Jul 5:33 pm                            %    0.00        OK

08 Jul 5:30 pm    100    44    15    NNW    3G08    126    16%            OK

08 Jul 5:18 pm                            %    0.00        OK

08 Jul 5:15 pm    99    45    16    SW    4G10    126    15%            OK

08 Jul 5:03 pm                            %    0.00        OK

08 Jul 5:00 pm    101    47    16    SSW    4G09    571    63%            OK

08 Jul 4:48 pm                            %    0.00        OK

08 Jul 4:45 pm    103    45    14    SW    4G15    571    59%            OK

08 Jul 4:33 pm                            %    0.00        OK

08 Jul 4:30 pm    103    38    11    ENE    4G08    659    64%            OK

08 Jul 4:18 pm                            %    0.00        OK

08 Jul 4:15 pm    103    38    11    ENE    3G08    659    60%            OK

08 Jul 4:03 pm                            %    0.00        OK

08 Jul 4:00 pm    100    44    15    SSW    3G13    714    62%            OK

08 Jul 3:48 pm                            %    0.00        OK

08 Jul 3:45 pm    104    44    13    SW    2G08    714    59%            OK

08 Jul 3:33 pm                            %    0.00        OK

08 Jul 3:30 pm    103    43    13    SW    4G14    802    64%            OK

08 Jul 3:18 pm                            %    0.00        OK

08 Jul 3:15 pm    105 42    12    SSW    6G15    802    62%            OK

08 Jul 3:03 pm                            %    0.00        OK

08 Jul 3:00 pm    101    41    13    SE    6G14    852    63%            OK

08 Jul 2:48 pm                            %    0.00        OK

08 Jul 2:45 pm    102    47    16    S    5G10    852    62%            OK

08 Jul 2:33 pm                            %    0.00        OK

08 Jul 2:30 pm    100    42    14    S    5G13    522    37%            OK

08 Jul 2:18 pm                            %    0.00        OK

08 Jul 2:15 pm    102    44    14    SSE    5G15    522    36%            OK

08 Jul 2:03 pm                            %    0.00        OK

08 Jul 2:00 pm    100    46    16    SE    2G14    923    63%            OK

08 Jul 1:48 pm                            %    0.00        OK

08 Jul 1:45 pm    101    48    17    S    2G15    923    62%            OK

08 Jul 1:33 pm                            %    0.00        OK

08 Jul 1:30 pm    100    46    16    SSE    6G17    945    63%            OK

08 Jul 1:18 pm                            %    0.00        OK

08 Jul 1:15 pm    99    45    16    SE    4G19    945    63%            OK

08 Jul 1:03 pm                            %    0.00        OK

08 Jul 1:00 pm    99    45    16    ESE    4G10    951    63%            OK


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Mike Haseler

News Snippet
Cooling caused wars, drought
SINGAPORE – AS CHINESE policymakers grapple with an expected increase in extreme weather due to global warming, a study has found that periods of cooling between AD 10 to 1900 also caused a wave of disasters, war and upheaval.
Droughts and locust plagues caused by cooler spells probably triggered internal wars, the authors said.

How well does that plastic flange insulate the sensor from the heat absorbed into that heavy steel elbow joint 5″ below it?

Joe Lalonde

You and your team make GREAT detectives to keeping science and the data honest!
Want to bet that this “record high” will be in the anomaly records and will be part of the hostest year ever?

Eric Gamberg

“NEWS Updated 07/16/2009 ”
Any plans to update the website on at least an annual basis?

Joe Lalonde

I know guys…”hostest” should have been “hotest”.
A honest mistake…………….honest!

“The station was installed by NOAA/NWS Phoenix personnel and it is their responsibility.”
I can hear them saying: “Good enough for government work!”
I’d like to know what these people are thinking when they install a sensor? Are they only following someone’s instruction? Are they going out there and willfully looking for a location that will assure the hottest possible readings? It’s almost like they all got an internal memo instructing them to install these things at the hottest imagineable spots.
An interesting case to say the least.


Again good detective work highlights yet more flawed data. How many times do you need to kick their shins for them to actually do something about it? Whoever is responsible for these networks needs naming and shaming.

Mike Haseler

Off topic – [snip]
[reply] Take it to tips and notes please. RT-mod

Geoff Sherrington

Time for discussion why stations 1200 km apart can be used to reconstruct each other (as in the Antarctic) while stations 1.2 km apart can differ by 5 deg F at about the same hour?

Warren in Minnesota

Note suspected spelling error: “…but this one has sever siting violations worth noting…”
sever should be severe
Reply: sever spelling error fixed. ~ ctm

FUBAR indeed !!!!!!!!!!!!
How many examples can be shown like this will it take for the AGW alarmists to at least question the validity of the data???????????????????

pgosselin says:
July 14, 2010 at 4:34 am
Are they going out there and willfully looking for a location that will assure the hottest possible readings? It’s almost like they all got an internal memo instructing them to install these things at the hottest imagineable spots.
Yet after they do that, they still adjust the data UP later !!!!!!!!!!!
Bad data X 2

stephen richards

They certainly were carefree when they installed it ! An unbelieveable lack of professionalism which appears to go to the heart of the whole organisation.
Anthony, had I been head of this organisation (national) I would not have wasted my time trying to prove you and your team wrong. I would not have wasted time trying to prove that poor siting makes no difference. I would have kicked some backsides into action and resited all the badly sited stations this one among them.


If scientists never calibrate their instruments, is it really science? Calibrate?! Oops, I meant never bother to check them at all. Welcome to climate science — where instruments are never accurate, studies are never replicated, dissent is never tolerated, and the incompetents running the circus are convinced they are never wrong.

It was probably installed there due to ease of installation. From the pictures you can see a light fixture near by and the security camera and other electronic equipment. What probably happened was that NOAA contracted the install out, the installers have no clue of siting requirements, they show up and ask the airport facilities manager where they can install the electonic sensors. The manager takes them around and shows them where all the other electronic and power cables run from inside to outside the building. So the installers piggy back the MMTS through the existing cable runs. This is something that anyone that has any electronic or electrical cable running experience would look for when running cables: It’s much easier and cheaper to run through an existing run then make a new one. Then they installed it up high like that because trenching through the asphalt, running a conduit and then re paving is even more money. Remember the contractor is going to try to do the job as cheap as he can to maximize his profit after being “low bidder”. Trust me I have seen this type of crap before when I was an Electronics Tech in the Navy and dealing with civilian contractors. Sometimes they have no clue about special requirements, they are just trying to do a job as fast as they can.

Mike Bryant

I’d love to see some FLIR thermal images of that station…


What’s a few acres of black asphalt among friends?


Not so much record air temperature as record amounts of charcoal on the BBQ.

Ron McCarley

NOAA’s website also states that approx. 50 of their 11,700 COOP stations are rooftop stations, and that a study was to be done about 10 yrs. ago. From what I’ve seen on the WUWT and Surfacestations websites, this 50 number seems to be low. Does anybody know if the actual study by NOAA was performed?


“I’d like to know what these people are thinking when they install a sensor?”
Oh, that’s easy to see if you’ve ever hired workmen to do any job. (and no insult, I’ve been there myself) If whoever gives them the job doesn’t say anything besides “go out and do it!” (typical) then they will always grab the closest and quickest path to completion. Why a roofbeam? It’s already there, and the wiring is short! Plus, putting it up above everyone ensures no one will drive their car into it or trip over it, meaning nobody will ever call up and complain and make you go back and do it over.
Well, except those science guys, but they take years to figure out something like this. It’ll probably be someone else’s job by then.

Dave N

I guess they have some Carefree barbecue summers there, and probably some winters, too!


Geoff Sherrington
Yes, I’ve wondered the same thing. Of course the anomaly method corrects for that 🙂

Atomic Hairdryer

It amazes me how sloppy processes are with NOAA. Write site guides, don’t bother checking they’ve been followed.
Years ago when digital cameras became cheap, we equipped all our field guys with cameras. Any time they visited a site, they’d take pictures and they’d be added to the site records. We then had a much better idea what we were working with, and saved a lot of time and money. We could plan work, mark up photos with what to install, where to install and connect. Field engineers knew what they were facing on a trip and had much better site guides to work with, and records if there was any dispute over the quality of the work.
Given the problems already discovered by the volunteers and the importance placed on the data collected, why hasn’t NOAA done their own field survey by now?

John Blake

Maximal incompetency over decades can only mean lack of any routine installation, monitoring or supervisory operating authority. Yet we’d bet that NOAA is overrun with administrators (sic) thick as cockroaches, who have no more interest in field-work than vetting prima facie discordant temperature results. Unless and until a civic-minded volunteer network supplants these swarms of “placemen” (Jefferson), full-throated AGW propaganda assaults at public expense will continue unabated.


So, with the recorded data having an error of +-5 oc, we can confidently assert that global temperatures have risen by +-0.1 oc per decade.
Something does not compute.

Steve Keohane

Thank you again Anthony. One can’t make this stuff up, reality is more bizarre than fiction. We are supposed to scrap the world economy to fix this CO2 induced problem.

Ian L. McQueen

As has been written more than once, siting the temperature sensors at airports makes perfect sense for the purpose for which they were installed: giving accurate temperature conditions at the airport for the benefit of the pilots flying the airplanes that use the airport.
The fault lies in using those same data for climate studies.
I must check- I thought I read within the past few days that a new network of 50 (approx) weather stations has been established with care in siting the stations across the USA. I recall reading that the data over the next (!) 30 years should give an accurate picture of true climate conditions.

Layne Blanchard

Don’t forget that nice hot motorcycle parked below either. They throw a tremendous amount of heat when they’re cooling down.

I once worked with a former US Navy jet jockey who had joined the service as an officer cadet straight from high school. He recounted that his first navy flying instructor gave a standard caution to all prospective service pilots;
“Remember that you will be flying aircraft supplied by the lowest tenderer and mostly assembled by high school drop-outs. Do your pre-flight checks as if your life depends on them… they probably do!”
Organisations are as bad as their laziest and most slipshod employee and if management don’t do the checks they should have formulated, nothing of value is acheived. The network of recording stations seems to be an example of how not to do stuff.

John Michalski

Seriuosly, though, with the availability of cell phones with cameras and digital cameras how much time would it take for NOAA to do photo survey of each and every site. It is my guess that within a weeks time, they would now the siting of each and every station. At that point in time, a plan of action could be set forth to re-site all out-of-compliance staions.


Makes perfect sense to me.
First, make sure that you are getting spuriously “reliable” warming data.
Second, enact draconian measures to reduce CO2.
Third, relocate sensors to “standard” sitings and easy as 1,2,3 AGW is solved as temperatures drop the amount that the models say and we are saved!

Dave Springer

Don’t know how much it effects the entire temperature record but it makes you wonder. One thing for sure is that it and stations like it make the record high temperatures (day and night all year long) incomparable with old records.


“Also of note, this station is used to adjust other stations nearby in the “homogenization” process, further polluting the climate record.”
Good grief
But they know exactly how much that asphalt is artificially heating the sensor,
so they know exactly how much to adjust for it…
and then they do the “homogenization” process, right?
This really is a joke.

stephen parrish

Interesting comment regarding continuous improvement and problem identification. Was at Disney in the spring and overhead either a new employee or an employee working a new process.
They had taken a picture with their phone of a less than perfect feature in the park and were sending it to service/maintenance so it could be repaired. The program they were using apparently identified where the picture was taken in the park provided the maintenance crew a chance to categorize the work and plan it.

Dave Springer

Tarmac power:
Say there’s 50,000 square meters of tarmac at the airport. In full sun at solar noon it’s receiving in excess of 1000 watts per square meter. Tarmac only reflects about 10% of that.
So it’s fair to say that temp sensor is situated above a 50 megawatt heater.

Henry chance

The Pepsi vending machine cranks out heat even at night. Mine had the compressor at the bottom and when barefoot, you could feel a fan push out hear 20 degrees hotter than the air around it.
I see the black pavement and am surprised the readings don’t hit 120 degrees at certain times of the day.

Tim Fitzgerald

More great research. I have a couple of questions and one comment:
Does the airport owned weather station have its own temperature sensor? What is the function of the airport owned weather station–it looks like they only report nearby fields in their AWOS. Are there any instances of airports that have AWOS/ASOS with a different set of equipment that report to the NCDC? It might be interesting to see the differences.
I don’t know if this is helpful, but I found this on the NWS website:

Jim Means

The “rooftop” comments are misleading. It is not at all mounted like the Baltimore rooftop (it’s on the side, not sitting on the rooftop). Temperature measured at that height would be expected to be LOWER, not HIGHER, because it is farther from the surface below it than it should be. Certainly not a good location, but your reasoning is faulty.
REPLY: Normally, yes height would matter, and the extra 1.5 meters would be cooler, However I’ll point out the Baltimore rooftop station was over a tar and gravel roof, not unlike asphalt. In a wind from the SE or E, heat from the airport office roof will transported to the sensor. -A


Not sure if this was an issue here, but here in AZ it is common, very common, for outdoor eating areas to use portable propane heaters in winter to make it possible to use the area when it is cold outside.
Maybe they do here, maybe they don’t, but just pointing that out…

Roger Knights

It’s a pity that short-range wireless transmission wasn’t legally available back when these new cable-connected stations were being installed. Then, practicality problems with trenching wouldn’t have forced poor siting. They should have waited until the laws were changed, or agitated for a special exemption using garage-door-opener frequencies, or something. Another case of institutionalized stupidity and short-sightedness.

John Michalski says:
July 14, 2010 at 6:57 am
Seriously, though, with the availability of cell phones with cameras and digital cameras how much time would it take for NOAA to do photo survey of each and every site. It is my guess that within a weeks time, they would know the siting of each and every station. At that point in time, a plan of action could be set forth to re-site all out-of-compliance stations.

It’s my impression that the gov’t. has site-photos, or was about to ask its sites to send in photos, in response to complaints about siting, but then canceled this data gathering for some reason, probably CYA-related. I also have the impression that it was Tom Karl who issued the cancellation order. (Please correct me if I’m wrong.)

Colin from Mission B.C.

You’ve overlooked the presence of the motorcycle, probably owned by one of the employees of the station. While relatively brief, the the ambient heat from the running engine plus the exhaust from the bike when it arrives, and when it’s started up to leave, would add extra heat to the area.
To describe this siting as FUBAR is being charitable.


Isn`t this link something worth as a seqence of Moshers artikel about global temperatures? I think its brilliant! stability of global air temperature estimates

Roger Knights

Let’s say that there were systematic siting problems that resulted in a cooling bias. Activists would have made a stink about it (“I blame Bush”) and the gov’t. would have relocated them in a jiffy. You know it’s true.
Viewed in that light, the station-siting issue reveals a problem larger than a mildly biased temperature record: an untrustworthy climatological establishment. I.e., if they’re willing to overlook systematic bias in this matter, why not in other climatological matters as well? Why should we trust ANY of their data or inferences? We don’t need no stinking weathermen.

Anthony, Do you routinely report bad sites, such as this one, to NOAA?
REPLY: Yes, I sent this to WSO Phoenix, plus that I get dozens of hits per day from throughout NOAA, NWS, NCDC. They know. -A


As a pilot I wonder how many such stations report bogus weather information I might use in my flight plan. Density altitude becomes rather important for a number of flight calculations – this is pathetic and probably criminal. But exactly what I expect of government.


As IanM correctly notes above, the pilots who use the airport are perfectly happy with temperature sensors which show the effects of asphalt heating.
Their lives depend upon safely loading light aircraft for ambient conditions.
If you estimate field temperature and use that to calculate the safe load and operating conditions of your aircraft, and your temperature estimate is high, you are safe.
If you estimate field temperature too low, you could die.
If I were a pilot at the airport, I’d mount the temperature sensor exactly as shown.
As has been noted many times here at WUWT, its just too bad that climate measurement and flight safety are at crossed purposes.
I hope that there will, in the future, be a separation of these two types of temperature recording systems.

Massimo PORZIO

I can understand the usefulness of reading the max and min temperatures of the day for statistical pourposes.
I don’t really figure out how that two daily parameteres could really be useful in the AGW arena.
A daily integral of them computed as (Tmax+Tmin)/2 can’t be in any manner used to establish any causal relation to the CO2 concentration.
It sounds like to guess the winner of a Formula One grand prix using the fastest speed for the prediction.
For example, in last Silverstone race Fernando Alonso scored the fastest lap and his Ferrari’s team fellow Felipe Massa scored the 2nd fastest lap, but they finished that race only 14th and 15th (sigh).

John C

Why is it that when people use this type of stuff to deny Global Warming, they fail to account for why correctly placed sensors still show an average increase in temperature?
In fact, all the sensors show anomalies in degree offset from the ‘norm’… So even if the temperature were to be 2 degrees higher, there would still be a noticeable upswing.
Do I deny that government will not try to take advantage of controlling Carbon emissions? No… Chances are they will. People should focus on this rather than trying to disprove data that shows our species is changing the environment. It’s ridiculous to think this is not possible. A major misunderstanding of science is rampant in these circles. People that claim that C02 isn’t capable of warming the atmosphere, etc. I can prove otherwise though a simple highschool experiment.
REPLY: You haven’t a clue about what you are writing about. Of 1067 stations surveyed in the USA (of 1221 in NOAA’s USHCN climate network) Only 1 in 10 of such sensors in the USA meet siting requirements, see With that sort of widespread FUBAR, how can we ” fail to account for why correctly placed sensors”. Nobody is “denying” anything. But the data they produce is most certainly suspect. – A

Hi Anthony,
Did you notice how fresh is the asphalt, and the white lines drawn on it ?
Could it be that the record is simply measuring how hot can be those big asphalt machines ?
By the way, I made a short french translation of this article in

Jim G

We called it “garbage in, garbage out” in the olden days. So, even assuming the model was not gabage itself, the poor quality of the input data, again assuming the data were not manipulated to compound the problem, would compromise validity of the results. Again, though, we are picking at fly droppings since the entire basis of the AGW theory is flawed by the causation problem and lack of true scientific methodology and statistical validity.
We need to emphasize the socio-economic penalties we will all pay if these people succeed in implementing their plans to “fix” our environment. Particular emphasis upon how severe their proposed policies will impact the “poor” for whom the progressives weep in all of their fake care for the little people of the world. For instance, they have done a great job of killing thousands of Third World folks with their ellimination of DDT.