WUWT readers may recall that I wrote about this experiment being performed at Oak Ridge national Laboratory to test the issues related to station siting that I have long written about.
This effort promises to be greatly useful to understanding climate quality temperature measurements and how they can be influenced by the station site environment.
From the USCRN Annual Report: http://www1.ncdc.noaa.gov/pub/data/uscrn/publications/annual_reports/FY11_USCRN_Annual_Report.pdf
Texas State Climatologist John Nielsen-Gammon writes about the the first results of this experiment presented at the recent AMS meeting in Austin, TX. The early results confirm what we have learned from the Surface Stations project. Nighttime temperatures are affected the most.
Two talks that caught my eye were on the land surface temperature record. They attacked the problem of land surface temperature accuracy in two completely different, but complementary ways.
One, by John Kochendorfer of NOAA at Oak Ridge, Tennessee, is a direct test of the importance of siting. They’ve installed four temperature sensors at varying distances across a field from the laboratory complex. The experiment has only been running since October, but already they’ve found out a couple of interesting things. First, the nighttime temperatures are indeed higher closer to the laboratory. Second, this is true whether the wind is blowing toward or away from the laboratory.
It’ll take a lot more data to sort out the various temperature effects. One way the buildings might affect the nighttime temperature even when the sensor is upwind of the buildings is infrared radiation: the heated buildings emit radiation that’s stronger than what would be emitted by the open sky or nearby hills.
More here: http://blog.chron.com/climateabyss/2013/01/dispatch-from-ams-looking-at-land-surface-temperatures/
Biases Associated with Air Temperature Measurements near Roadways and Buildings
Wednesday, 9 January 2013: 9:15 AM Room 15 (Austin Convention Center)
John Kochendorfer, NOAA, Oak Ridge, TN; and C. B. Baker, E. J. Dumas Jr., D. L. Senn, M. Heuer, M. E. Hall, and T. P. Meyers
Abstract
Proximity to buildings and paved surfaces can affect the measured air temperature. When buildings and roadways are constructed near an existing meteorological site, this can affect the long-term temperature trend. Homogenization of the national temperature records is required to account for the effects of urbanization and changes in sensor technology. Homogenization is largely based on statistical techniques, however, and contributes to uncertainty in the measured U.S. surface-temperature record. To provide some physical basis for the ongoing controversy focused on the U.S. surface temperature record, an experiment is being performed to evaluate the effects of artificial heat sources such as buildings and parking lots on air temperature. Air temperature measurements within a grassy field, located at varying distances from artificial heat sources at the edge of the field, are being recorded using both the NOAA US Climate Reference Network methodology and the National Weather Service Maximum Minimum Temperature Sensor system. The effects of the roadways and buildings are quantified by comparing the air temperature measured close to the artificial heat sources to the air temperature measured well-within the grassy field, over 200 m downwind of the artificial heat sources.
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Early results of what has been learned in the surface stations project can be seen here:
New study shows half of the global warming in the USA is artificial
h/t to Dr. Roger Pielke Sr.
For those who underestimate the impact of heat radiation, it is much like conduction. The individual photons bearing the heat energy, in their own frame, simply step across from source to target without any passage of time in between — time does not elapse at the speed of light. It’s well known that in a forest fire what you must avoid is open exposure to flames at medium distance — because the heat radiation kills. Therefore it can’t be a surprise that heat radiation from buildings will directly heat a thermometer casing at a medium distance.
What matters is not whether temperatures are different near buildings, but whether temperature anomalies i.e the deviation from average, are different. Is there anything in the study on this? After all, if the sensor in the field is always cooler, then it makes no difference to the deviations from average.
Why is it always worse than I suspect? The temperature data is not even good enough for government work.
Does this one site test, reaffirm Michel Leroy’s methodology?
Slightly OT, the temperature sensors used by the AWOS (Automatic weather observation stations) here in Canada are reported by Nav-Can as sensor model YSI 44034, specification sheet gives a range of -40 to 20C.Accuracy in that range as 0.01C.( might be 0.001C forgot already)
This is the ongoing upgrade to Environment Canada’s system, does anyone know what sensor the system 1990 to 2010 uses,its working range and accuracy.
This end of range at -40C, at arctic stations, strikes me as willful blindness, if true.
In a bizarre way, this does prove the warming detected was AGW,..not from the CO2, but from their buildings! 🙂
True vindication will come when NOAA recognizes, acknowledges, and INCLUDES confirmation of Watts et al in this research when published and made public.
What would really quantify and confirm the accuracy of NOAA’s adjustments would be them publishing previous station adjustment methods, along with the same adjustments made to these known 5 in this study.
Well this is indeed personal vindication for me as well as I had literally described in detail the exact experiement required to determine the amount of heat noise produced in micro-climates over short distances.
Posted on the on the BEST update post at Climate, etc. Steven Mosher did the “snap” denial of an impact on BEST. Because they didn’t use an urban sites. LOL.
k scott denison | January 20, 2013 at 5:45 pm | Reply
Noted that WUWT has a report about NOAA experiment showing that siting affects nighttime temperatures… always warmer near buildings regardless of wind direction.
Wonder how this affects the BEST data?
http://wattsupwiththat.com/2013/01/20/noaa-establishes-a-fact-about-station-siting-nighttime-temperatures-are-indeed-higher-closer-to-the-laboratory/
Steven Mosher | January 20, 2013 at 5:57 pm | Reply
In the UHI paper we only used stations that were free of urban influence to a 10km radius. so effectively we used no stattions close to buildings.
Trends dont change.
Impossible! The science is settled, $2.5 billion was spent, whole businesses (phony) created and (real) destroyed. The price of everything increased, fuel and energy poverty, food gone into gas tanks as bio-fuel and sundry little thing’s like the middle East exploding due to the high cost of living and food. No big deal to the watermelons.
PS – I could have done this little experiment for a $100 and 3 or 4 spare evenings, How much of taxpayers money went into the obvious. So much for higher education!!!!
There are a lot of DUH comments – justifiably – but please note that criticism is due to all those who did NOT do any testing, much more than it is due to those who at least ARE testing even if rather late.
It is depressing that the world of science so often takes so long to apply a simple test. As for Marshall and Warren, where all the orthodoxy had to do was take a look, but it took them 20 years.
Perhaps Anthony or someone else can point us to a link that documents the history of temperature loggers. I recall the early ones could only be a short distance from the computer and were sited on or near the sides of buildings.
I’d be interested in knowing if their introduction coincided with the ‘warming’ that started in the mid-1970s.
Konrad says:
“Nighttime temperatures are affected the most.”
As I recall, warming that showed a greater rise in Tmin than the rise in Tmax was supposed to be the “Signature of CO2 induced AGW”.
You remember correctly. Except now we can say it’s a theoretical fingerprint of GHG warming and an observed fingerprint of UHI effect.
Good comments. The “UHI error” cannot be deconvoluted from the real temps because the UHI effect must be measured at each station. Wind speed and direction are major variables here.
I repeat, UHI effect must be quantified at EVERY STATION to permit subtraction of any error. This has not been done. The UHI error story is the most important salient weakness to the historical temperature record.
For Tom and others, National Weather Services did (and do) have station siting criteria, rules for recording temps, and what color of paint to use on the screens, but those rules were not enforced. The people reading the thermometers may or may not have been reliable on every daily recording. Recording insturmentation goes out of calibration or fails.
W all need to face the reality that there are no scientifically reliable surface temperature measurements before the creation of the Climate Reference Network. If you want reliable tems, then you need to look at the records of individual rural stations that never changed in any way in 100 years, including the individual who read the thermometer and recorded the readings, then you might get some trend line worthy of making climate claims, but such stations do not exist and there is no way to recover good data that was never scientifically reliable in the first place. If you know data are contaminated you must reject the data. The application of “night lighting” estimates to “gridded” and “homogenized” data is not accepted.
Those few individual rural stations with long term stability, and some semblence of scientific discipline, in the UK or Europe, show ZERO long term warming. There are 4 science stations in Antarctica, Amundsen-Scott, Vostok, Halley and Davis that have a reliable temperature record since 1957, those stations all show ZERO warming.
The Surfacestation.org project is a huge benefit to understanding the AGW story. Most people live their lives in marvel at daily technological advances, so fail to fully appreciate that some “scientists” CAN be politically corrupt, mediocre, self-serving or imcompetent. The same goes for the so-called “science” promoting societies like the Royal Society, AAAS, ACS, etc.
Trenberth’s missing heat.
I suggest we wait for the models to tell us whether the information gleaned from this experiment is useful. I mean, experiments are all well and good, but …
/sarc
Invest in an electric storage heater now, while stocks last.
http://www.ecopowerheating.co.uk/2011/07/night-storage-heaters-chocolate-fireguards-ebay-has-it-all/
DTR
http://meteolcd.wordpress.com/2013/01/20/new-best-paper-global-dtr-trend-flat-as-shown-by-meteolcd/
I have to believe that at least some of the faults of NOAA’s siting is due to the fact that previously
nobody much cared about the ability to discern small changes over time – 67 degrees was OK , even if it was really 68, because that was close enough for the purposes it was being used for.
Or am I mistaken in this belief?
Steven Mosher says:
January 20, 2013 at 2:53 pm
“ahem. arnt you forgetting who first pointed this experiment out to you?”
I have been pointing out the need for such experiments for years. Why did it take so long to do the experiment. Will they do the necessary work on all their sites? Will they report that this work undermines most of their surface temperature records?
Oh, wait. Does this mean they are going to have to go back and adjust every station that isn’t near a building or concrete or some other heat source to raise it to match the poorly sited locations? Seems to me they keep looking for excuses to make additional upward adjustments. First they adjusted rural stations up to match UHI. Now they are going to have to adjust well-sited locations up to match the poorly-sited ones.
jimmi_the_dalek says:
January 20, 2013 at 3:14 pm
Why would you or anyone assume that the distortions introduced into measurements are uniform? That is not science. The experimental work must be done.
Has anyone studied micro-heat islands? My very small town is a heat island, I know it but the heat islands I read about are much larger.
I understand that these researchers have since submitted a new grant proposal to examine whether or not a watched pot boils.
I’m pleased that someone has actually bothered to measure this (and in what appears as a rural location too?)
However, in practise, most scientific folk have known about this type of problem for many years but it was never considered as being important because the effect is assumed to be constant, which in short timescales, it pretty well is – only when new build and towns are constructed around stations will a noticeable effect be seen. I believe this is one of the reasons UHI was always ‘dismissed’. The trouble is that we all know it is significant and more importantly is far more significant than they would like to admit. Hundreds of station data should probably be lowered as a result of cumulative UHI, but I have no idea how much adjustment for it has been done, or from when , or based on what criteria!
I don’t know about the USA – but outside my house, (solid walls with no means of cavity insulation) I know it radiates a good deal of heat because on a cold frosty morning I see that my car has no frost on the side nearest the house, but well frosted on the other side. Hence, the house is emitting significant radiation to keep the facing side of my car ‘frost free’, QED. But of course, if we put several hundred thousand houses in close proximity into an area I dunno, let’s call it, a town, or many more together and call it, a city – and lets call the effect of lots of this heat radiation, ‘UHI’ – the data keepers still do not think it is significant and not really an issue when considering ‘global’ rising temperatures, despite increased town sizes, increased use of central heating, paved roads, infrastructure, etc ……yeah, right!
tom streck says: Can’t believe this experiment wasn’t done many years ago. After all, there is siting criteria for stations. Didn’t they experiment at that time to come up with good siting conditions??
If Bolivia had no money to do this astonishingly expensive experience ten years ago, all right, but the powerful NOAA ……
crosspatch says:
January 20, 2013 at 4:09 pm
Haha – quite possibly! I can imagine the rural stations will next be argued to be artificially ‘cooled’ as a result of open access to wind chill for example – compared to all those sheltered urban stations! Watch out – it’ll probably happen!
I’m willing to bet that 97% of scientists assumed that these experiments had already been done years ago by those clever people at the IPCC.
And the other 3% were merely gobsmacked.