PRESS RELEASE – U.S. Temperature trends show a spurious doubling due to NOAA station siting problems and post measurement adjustments.
Chico, CA July 29th, 2012 – 12 PM PDT – FOR IMMEDIATE RELEASE
A comparison and summary of trends is shown from the paper. Acceptably placed thermometers away from common urban influences read much cooler nationwide:
A reanalysis of U.S. surface station temperatures has been performed using the recently WMO-approved Siting Classification System devised by METEO-France’s Michel Leroy. The new siting classification more accurately characterizes the quality of the location in terms of monitoring long-term spatially representative surface temperature trends. The new analysis demonstrates that reported 1979-2008 U.S. temperature trends are spuriously doubled, with 92% of that over-estimation resulting from erroneous NOAA adjustments of well-sited stations upward. The paper is the first to use the updated siting system which addresses USHCN siting issues and data adjustments.
The new improved assessment, for the years 1979 to 2008, yields a trend of +0.155C per decade from the high quality sites, a +0.248 C per decade trend for poorly sited locations, and a trend of +0.309 C per decade after NOAA adjusts the data. This issue of station siting quality is expected to be an issue with respect to the monitoring of land surface temperature throughout the Global Historical Climate Network and in the BEST network.
Today, a new paper has been released that is the culmination of knowledge gleaned from five years of work by Anthony Watts and the many volunteers and contributors to the SurfaceStations project started in 2007.
This pre-publication draft paper, titled An area and distance weighted analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends, is co-authored by Anthony Watts of California, Evan Jones of New York, Stephen McIntyre of Toronto, Canada, and Dr. John R. Christy from the Department of Atmospheric Science, University of Alabama, Huntsville, is to be submitted for publication.
The pre-release of this paper follows the practice embraced by Dr. Richard Muller, of the Berkeley Earth Surface Temperature project in a June 2011 interview with Scientific American’s Michael Lemonick in “Science Talk”, said:
I know that is prior to acceptance, but in the tradition that I grew up in (under Nobel Laureate Luis Alvarez) we always widely distributed “preprints” of papers prior to their publication or even submission. That guaranteed a much wider peer review than we obtained from mere referees.
The USHCN is one of the main metrics used to gauge the temperature changes in the United States. The first wide scale effort to address siting issues, Watts, (2009), a collated photographic survey, showed that approximately 90% of USHCN stations were compromised by encroachment of urbanity in the form of heat sinks and sources, such as concrete, asphalt, air conditioning system heat exchangers, roadways, airport tarmac, and other issues. This finding was backed up by an August 2011 U.S. General Accounting Office investigation and report titled: Climate Monitoring: NOAA Can Improve Management of the U.S. Historical Climatology Network
All three papers examining the station siting issue, using early data gathered by the SurfaceStations project, Menne et al (2010), authored by Dr. Matt Menne of NCDC, Fall et al, 2011, authored by Dr. Souleymane Fall of Tuskeegee University and co-authored by Anthony Watts, and Muller et al 2012, authored by Dr. Richard Muller of the University of California, Berkeley and founder of the Berkeley Earth Surface Temperature Project (BEST) were inconclusive in finding effects on temperature trends used to gauge the temperature change in the United States over the last century.
Lead author of the paper, Anthony Watts, commented:
“I fully accept the previous findings of these papers, including that of the Muller et al 2012 paper. These investigators found exactly what would be expected given the siting metadata they had. However, the Leroy 1999 site rating method employed to create the early metadata, and employed in the Fall et al 2011 paper I co-authored was incomplete, and didn’t properly quantify the effects.
The new rating method employed finds that station siting does indeed have a significant effect on temperature trends.”
Watts et al 2012 has employed a new methodology for station siting, pioneered by Michel Leroy of METEOFrance in 2010, in the paper Leroy 2010, and endorsed by the World Meteorological Organization (WMO) Commission for Instruments and Methods of Observation (CIMO-XV, 2010) Fifteenth session, in September 2010 as a WMO-ISO standard, making it suitable for reevaluating previous studies on the issue of station siting.
Previous papers all used a distance only rating system from Leroy 1999, to gauge the impact of heat sinks and sources near thermometers. Leroy 2010 shows that method to be effective for siting new stations, such as was done by NCDC adopting Leroy 1999 methods with their Climate Reference Network (CRN) in 2002 but ineffective at retroactive siting evaluation.
Leroy 2010 adds one simple but effective physical metric; surface area of the heat sinks/sources within the thermometer viewshed to quantify the total heat dissipation effect.
Using the new Leroy 2010 classification system on the older siting metadata used by Fall et al. (2011), Menne et al. (2010), and Muller et al. (2012), yields dramatically different results.
Using Leroy 2010 methods, the Watts et al 2012 paper, which studies several aspects of USHCN siting issues and data adjustments, concludes that:
These factors, combined with station siting issues, have led to a spurious doubling of U.S. mean temperature trends in the 30 year data period covered by the study from 1979 – 2008.
Other findings include, but are not limited to:
· Statistically significant differences between compliant and non-compliant stations exist, as well as urban and rural stations.
· Poorly sited station trends are adjusted sharply upward, and well sited stations are adjusted upward to match the already-adjusted poor stations.
· Well sited rural stations show a warming nearly three times greater after NOAA adjustment is applied.
· Urban sites warm more rapidly than semi-urban sites, which in turn warm more rapidly than rural sites.
· The raw data Tmean trend for well sited stations is 0.15°C per decade lower than adjusted Tmean trend for poorly sited stations.
· Airport USHCN stations show a significant differences in trends than other USHCN stations, and due to equipment issues and other problems, may not be representative stations for monitoring climate.
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We will continue to investigate other issues related to bias and adjustments such as TOBs in future studies.
FILES:
This press release in PDF form: Watts_et_al 2012_PRESS RELEASE (PDF)
The paper in draft form: Watts-et-al_2012_discussion_paper_webrelease (PDF)
The Figures for the paper: Watts et al 2012 Figures and Tables (PDF)
A PowerPoint presentation of findings with many additional figures is available online:
Overview -Watts et al Station Siting 8-3-12 (PPT) UPDATED
Methodology – Graphs Presentation (.PPT)
Some additional files may be added as needed.
Contact:
Anthony Watts at: http://wattsupwiththat.com/about-wuwt/contact-2/
References:
GAO-11-800 August 31, 2011, Climate Monitoring: NOAA Can Improve Management of the U.S. Historical Climatology Network Highlights Page (PDF) Full Report (PDF, 47 pages) Accessible Text Recommendations (HTML)
Fall, S., Watts, A., Nielsen‐Gammon, J. Jones, E. Niyogi, D. Christy, J. and Pielke, R.A. Sr., 2011, Analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends, Journal of Geophysical Research, 116, D14120, doi:10.1029/2010JD015146, 2011
Leroy, M., 1999: Classification d’un site. Note Technique no. 35. Direction des Systèmes d’Observation, Météo-France, 12 pp.
Leroy, M., 2010: Siting Classification for Surface Observing Stations on Land, Climate, and Upper-air Observations JMA/WMO Workshop on Quality Management in Surface, Tokyo, Japan 27-30 July 2010 http://www.jma.go.jp/jma/en/Activities/qmws_2010/CountryReport/CS202_Leroy.pdf
Menne, M. J., C. N. Williams Jr., and M. A. Palecki, 2010: On the reliability of the U.S. surface temperature record, J. Geophys. Res., 115, D11108, doi:10.1029/2009JD013094
Muller, R.A., Curry, J., Groom, D. Jacobsen, R.,Perlmutter, S. Rohde, R. Rosenfeld, A., Wickham, C., Wurtele, J., 2012: Earth Atmospheric Land Surface Temperature and Station Quality in the United States. http://berkeleyearth.org/pdf/berkeley-earth-station-quality.pdf
Watts, A., 2009: Is the U.S. surface temperature record reliable? Published online at: http://wattsupwiththat.files.wordpress.com/2009/05/surfacestationsreport_spring09.pdf
World Meteorological Organization Commission for Instruments and Methods of Observation, Fifteenth session, (CIMO-XV, 2010) WMO publication Number 1064, available online at: http://www.wmo.int/pages/prog/www/CIMO/CIMO15-WMO1064/1064_en.pdf
Notes:
1. The SurfaceStations project was a crowd sourcing project started in June 2007, done entirely with citizen volunteers (over 650), created in response to the realization that very little physical site survey metadata exists for the entire United States Historical Climatological Network (USHCN) and Global Historical Climatological Network (GHCN) surface station records worldwide. This realization came about from a discussion of a paper and some new information that occurred on Dr. Roger Pielke Sr. Research Group Weblog. In particular, a thread regarding the paper: Pielke Sr., R.A., C. Davey, D. Niyogi, S. Fall, J. Steinweg-Woods, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim, H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, R.T. McNider, and P. Blanken, 2007: Unresolved issues with the assessment of multi-decadal global land surface temperature trends. J. Geophys. Res.
2. Some files in the initial press release had some small typographical errors. These have been corrected. Please click on links above for new press release and figures files.
3. A work page has been established for Watts et al 2012 for the purpose of managing updates. You can view it here.
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Note: This will be top post for a couple of days, new posts will appear below this one. Kinda burned out and have submission to make so don’t expect much new for a day or two. See post below this for a few notes on backstory. Thanks everybody! – Anthony
NOTE: 7/31/12 this thread has gotten large and unable to load for some commenters, it continues here.
Bravo Anthony at al, well done, good to see science at work!
Skeptics are vindicated, comments about data and adjustments are endorsed now with scientific papers asking for more quality data and work!
This issue of station sitting quality was also my feeling that the majority of USHCN data is “UHI poluted”.
It was also my understanding why BEST found decreasing trend in “most urban” against the whole database. “Most urban” are already big cities where the growth is no longer as significant as in smaller areas.
In the 20th century there was worldwide urbanization process and an interesting demographic evolution. Many big cities have “grown up” and a big part of the world reached over 90% urbanization and also ceased to grow. We have seen this in almost all developed countries, with stagnation in Europe, Russia, Japan, South Korea limited growth in North America and Australia, now followed up by China and others.
Interesting to note that the absolute population growth was 75 million in 1968 and also 75 million in 2010 at double the population. But the new 75 million do not add in the same locations.
This phenomenon starts to happen in the 1950s and continues on a larger scale in the next years.
As more and more cities grow and reach a level of what I would call “UHI saturation”, the slow growth of big cities and smaller in absolute values UHI increase for cities from a certain size explains a smaller delta UHI for an urban group that contains cities, in comparison with a UHI contaminated average containing many small locations growing – consistent with the results from the BEST study – divergence appearing in the 1950s – and with the logarithmic dependency of UHI growing trend based on population.
The time period when this de-couplement happens and the increased difference is consistent with the global demography.
Your paper addresses only the time frame from 1979-2008 in the US but it clearly points out at the flaws of not proper using the meta-data of the stations sitting and making statistical adjustments irrelevant to the meta-data and will hopefully serve to a correction of the race to the highest adjustments trend. (It is not only UHI but various stations sitting issues, I know).
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Toby says:
July 29, 2012 at 12:21 pm
The US is how much? 2% of the earth’s surface.
But it is warming at 0.155C/ decade, not far off the IPCC expectation of ~0.2C/decade.
Seems like good and valuable contributory work, to add to the confirmatory analysis of the BEST group of Richard Muller.
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Toby, the world did not start to exist with your birth, even if it might appear so to you. If you go and see unadjusted temperature data for longer periods you’ll understand the 0.155C/decade
in a different perspective:
http://hidethedecline.eu/pages/ruti/north-america/usa-part-1.php
So the dreaded global warming IS man-made – all that affecting concrete, those a/c units, buildings road and airports, yep, every one of them is man-made !
Alan Douglas
REPLY – Some of it, certainly. And some natural warming over the positive PDO period. But there’s still some room for anthropogeniety ~ Evan
So, this means that AGW (or a good portion of it) is really man-made….just not by [CO2]…
REPLY – Mmmm. A good portion, yes. ~ Evan
Just curious … any document downloads from RC or NASA GISS domains yet? Again, just curious and good work …
“Be careful, not to be carried away by your enthusiasm. The difference between what you say in the paper and in the powerpoint presentation:”
I’m going to take Leif’s word concerning how this probability should properly be characterized. And I agree with his larger point, that there’s no need to exaggerate (if that’s what you’re doing). Why give your critics ammunition when you don’t have to? Only weakens an otherwise apparently very strong paper..
Just great!
Query legend: Should the lowest be 0.0 ? And third lowest be 0.05 – 0.1?
Apologies if someone’s already on to this.
To paraphrase someone or other:
I am absolutely certain that generations from now, we will be able to look back and tell our children that this was the moment when we began to provide sound science for the people and reassurance to the scared-snipless; this was the moment when the rise of bullsnip began to slow and our political discourse began to heal; this was the moment when we ended the climate-war and secured our nation and restored our image as the last, best hope on earth.
Eh…I’m British, so that last bit doesn’t really work.
Anyway, I can’t miss this opportunity. Hi, Mr. science historian from the future. Give my regards to my great-great-grandson, tell him to work hard at cyber-school and put down those augmented reality glasses once in a while.
P.S. The rumours are true. People in the 2010’s didn’t have to get permission from Department of Political Corrections to express a new opinion. We really did inhale smoke from burning leaves wrapped in paper and drank liquids that killed our brain cells. You don’t know what you’re missing.
But the methodological implications seem to go beyond the USA.
Reminds me of back in 2007 when McIntyre had found Hansen’s Y2K error that misrepresented 2006 instead of 1934 as the US’s warmest year.
Does Hansen’s Error “Matter”?
Steve McIntyre, posted on Aug 11, 2007 at 1:44 PM
http://climateaudit.org/2007/08/11/does-hansens-error-matter/
The song remains the same!
It’s my birthday today. Thank you Anthony for a wonderful present. You put in a lot of hard work. And good science. A very many people are grateful. Thank you.
Leif Svalgaard says:
July 29, 2012 at 12:54 pm
Do don’t such things.
REPLY – Depends on your definitions. For all nine areas to be cooler fro Class 1\2 is a 1/512 shot. For all nine to be significantly cooler is more like 1 in 20,000. Then on top of that, it holds for all 5 slices of data. That’s pretty darn vanishingly minuscule. ~ Evan
That is not the point. There is quite a difference between ‘quite small’ and ‘vanishing minuscule’ or do you think the difference is vanishing minuscule?. Furthermore, the data are not independent so your calculation of probability is wrong. The point is: you should say the SAME in both presentations.
REPLY – Point taken. ~ Evan
Excellent! I knew there had to be more research into these warming biases coming.
A few scoffers have popped up to say “yes but USA is only 2% of world’s surface….” Yes but if the stats from the most advanced nation in the world are basically wrong/overstated, what credence should we give to data coming out of Africa, S America, for the sake of obvious examples, which together comprise a significant fraction of the worlds surface? If the USA is wrong, nothing (much) is right, therefore we have no reliable global temperature record, therefore global warming may/may not be happening, nobody really knows, in which case policy responses are a trifle premature. The ponzi politicos will have to think of a better wheeze to keep their show on the road.
Line 464: I recommend
“The gridded average of all compliant rural MMTS Class 1&2 stations…” to emphasize that we are still discussing figure 8 in the new paragraph.
Nice work! Could use a few of those NOAA “adjustments” on payments into my bank account …
I bet the BBC does not report this article on the TV or the red button!!
Toby says:
July 29, 2012 at 12:21 pm
Thanks, Toby. Several comments.
First, although the US is only 2% of the earth’s surface, it has arguably the most dense network of stations, and in part because of this, figures regarding the US trends are quoted endlessly.
Second, the same errors almost undoubtedly exist in the rest of the world. It would be foolish to assume they do not. Since this analysis establishes that the canonical estimate of the US trends is almost double the reality, the same is likely true of the rest of the world.
Third, it does not “confirm” the work by Mueller, it directly contradicts and refutes Mueller’s claims. Read the paper.
Fourth, the trends reported are for 1979-2008. The IPCC “expectation of ~0.2C/decade” has not been seen in the last decade of that period … where did it go? No one knows, but post about 1995 the planet definitely has not been warming as the IPCC expected.
All the best,
w.
A quick comment.
None of you posting here have any idea if there is an error in Anthony et al.’s work.
Caution and criticism are likely to be more helpful to him than simple cheering.
The honorable Mr. Delingpole is the first to run the story,
http://blogs.telegraph.co.uk/news/jamesdelingpole/100173174/global-warming-yeah-right/
Followed by the Boston Environmental Policy Examiner,
http://www.examiner.com/article/devasting-blow-to-temperature-records-u-s-temp-trends-spuriously-doubled
Stephen Wilde says:
July 29, 2012 at 12:15 pm
“surface area of the heat sinks/sources within the thermometer viewshed to quantify the total heat dissipation effect.”
Neat.
Common sense at last.
C’est nous !! The French are renowned for their common sense that’s why we find the English so difficult to understand.
And if anyone wants to send non-climate-blog-reading friends a slightly less technical take on this, it’s here:
http://wp.me/pnsGM-i1
How do you explain the fact that the UAH and RSS CONUSA trend is 0.24°C/dec, Klotzbach (corrected) says the surface-TLT land-only amplification factor is 1.1, and yet you’re arguing for a surface trend of 0.155°C/dec? That’s more than a 1.5 amplification factor.
Either UAH and RSS are biased high or your results are biased low, and frankly the former explanation is not very plausible.
[REPLY: Didn’t read the paper, did you Dana? Didn’t think so. -REP]
Congratulations to Anthony and the other authors for a well written, readable paper. This is real science applied with care. Having the data and algorithms available shows the level of class we’ve all experienced on this website.
For those cheering that there’s no global warming (US warming), yes there is, it’s just not CAGW. Does mankind contribute, is there any AGW? Certainly, we contribute in land use changes, and in topographical changes. Is this really changing the temperature of the planet – yes, but on any given day you’d be hard pressed to feel it, with possible exceptions like the enthalpy of desert regions increasing with the increase in irrigation of yards, crops, etc.
For those protesting this is “only” 2% of the planet, that’s a little off. If the oceans areas are deducted from the surface area, then >25% of North America is a significantly larger chunk of the puzzle. Getting the measurements right here, will go a long way to getting measurements right everywhere – with a Global standard!
And for all those reveling in the feeling of having “our” website set things right, I’ll revel when we get to where this won’t even be a topic for discussion, when correct metrology is a given, not a 1/3 chance (metrology is the science of measurement). In my mind that will occur when we regularly measure the enthalpy of the environment and lead with that, not just the temperature. It was one of the significant points in the paper that this was brought up vis-a-vis the stations in the area of water treatment plants.
Well done, simply well done.
Sentence starting on line 299 seems to need attention on line 300
“…proximity and area ratings from Leroy 2010 and are do consider ground-level vegetation…”
the “and are do” bit.
It’s a good read so far.
it doesn’t matter. It’s only the United States. You haven’t proved that there are problems anywhere else in the world
Well, you do gotta consider that the same boyz that adjust the USHCN also adjust the GHCN, though. So we’re talkin’ “anywhere else in the world”, by definition.