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.
Anthony, Thanks for all that hard work. You are saving science from the zealots!
I was really struck by the rural MMTS non airport trend. What would the error bars be if that set of Class 1/2 stations alone was used to define the continental US trend? Would they overlap the error bars around the USCHNv2 trend?
Here is the Abstract I would have written (244 words). If it does not reflect that your finding is, you have failed to get the message across:
“We use the siting classification system developed by Michel Leroy for Meteofrance in 1999 and improved in 2010 which quantifies the effect of heat sinks and sources within the thermometer viewshed by calculation of the area- weighted and distance-weighted impact of biasing elements to calculate both raw and gridded 30 year for each surveyed station, using temperature data from USHCNv2. Mean temperature trend is indisputably lower for well sited stations than for poorly sited stations. Minimum temperature trend shows the greatest differences between siting classification while maximum temperature trend shows the smallest. Well sited stations consistently show a significantly lower trend than poorly sited stations, no matter which class of station is used for a baseline for comparison, and also when using no baseline at all. Comparisons demonstrate that NOAA adjustment processes fail to adjust poorly sited stations downward to match the well sited stations, but actually adjusts the well sited stations upwards to match the poorly sited stations. Well sited rural stations show a warming nearly three times greater after USHCNv2 adjustments are applied.4 It is also demonstrated that urban sites warm more rapidly than semi-urban sites, which in turn warm more rapidly than rural sites. We document this large urban bias in station siting on the Global Historical Climate Network. 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.”
At 9:09 PM on 29 July, Leif Svalgaard submitted a suggested recasting of the abstract for this manuscript, stating:
For what my opinion is worth – not much, as I’m a physician, not a physicist – this version should be seriously considered by Mr. Watts and his fellow authors.
At the very least, it shows that concision is possible while maintaining appropriate representation of the study’s purpose, results, and conclusion.
Again, in my opinion (and again, for what that opinion is worth), Dr. Svalgaard’s experience with academic peer review qualifies him as a commenter whose suggestions should be received as having a high level of reliability.
calculate both raw and gridded 30 year for each surveyed station
Err, 245 words: ” calculate both raw and gridded 30 year trends for each surveyed station”
Is this what all the hype was about? A poorly written manuscript yet to be submitted? I am genuinely curious though, which journal does Anthony think this manuscript is going to be published in? The formatting is terrible.
REPLY: We are all still waiting for you to produce something of value other than whining from behind the curtain of anonymity.
Everyone should have a look at this on his blog to know the kind of person he is: Denier Comment of the Day July 30, 2012
Step of or shut is always a good policy I think. Write your own paper, make a difference. leave a note when you have substances, because I don’t have to take the sort of juvenile abuse you write on the blog of yours. Note my “living room policy” on the policy page, I’m showing you the door. I’m also going to drop a note to Charles Sturt University to advise them of your abuse of their AUP. – Anthony
Well done Anthony, co-authors, and moderators.
An example of media take up:
http://tucsoncitizen.com/wryheat/2012/07/29/us-temperature-trends-show-a-spurious-doubling-due-to-noaa-station-siting-problems-and-post-measurement-adjustments-says-a-new-study/
Important work done by an excellent team.
Harold Pierce Jr says:
July 29, 2012 at 6:00 pm
I love a guy that can’t spell “temperatures”, can’t spell “measured”, puts a space in front of a period, claims people look like a “bunch sloppy scientists”, and can’t spell “amateurs”, who nonetheless claims that the mark of a professional is “close attention to detail”.
By your own standard, you have just proven beyond doubt that you are the rankest of amateurs, Harold. Medice, cura te ipsum!.
w.
PS—In the expression “et al.”, the word “al.” is an abbreviation for “alia”, and as such also requires a period … in case you were wondering.
I don’t know how Prof. Muller can have the nerve to go on another publicity spree when the draft manuscripts associated with his previous publicity drive last year still have not been approved. I know the BEST study was extremely complex, but such a long period from initial submission does not exactly inspire confidence in terms of quality of work and attention to detail, especially in terms of organisation and presentation of underlying data / metadata. Does he really think the public are that stupid? The posturing as to being a “reformed sceptic” is also particularly contemptible. We are not all blind unquestioning followers of NYT/Grauniad collectivism.
Well done Anthony et al., as a rationalist though time will be required to absorb the work in full. It does appear though that Prof. Muller may now have further headaches in getting his draft manuscripts approved (now five of them in the queue). It will be v. interesting to see how the IPCC handles this all wrt. AR5.
Again, in terms of a fundamental lack of attention to detail, Prof. Muller et al. have shown incompetence by overlooking WMO station siting standards, which as a UN organisation they can hardly criticise now even if they may wish to do so. The impact of Anthony’s work is indeed potentially tectonic, as so many research papers have been reliant on NOAA data. I think Dr. Roger Pielke Sr. has put it best in terms of alluding a confirmation bias.
The work performed by Anthony, with limited resources should have been performed by the “public servants” themselves, who are funded by vast taxpayer resources, and do not appear to have been performing anything resembling ‘normal’ science.
Critical minds and citizen engagement at work!
Congratulations and thanks, Anthony – for your dedication and years of hard work!
The new improved assessment, for the years 1979 to 2008, yields a trend of +0.155C per decade from the high quality sites
Comments were made about factoring in relative humidity and the fact that it ends in 2008. Taking the sea surface data from 1979 to 2008 yields a slope of slope = 0.0135164 per year. However taking the slope from 1979 to date gives a slope of slope = 0.0124303 per year. So perhaps if the time were taken up to the present, it may also possibly be only +0.145C/decade. And taking sea surface temperatures of course eliminates the need to consider relative humidity. However one should also not ignore the fact that warming stopped over 15 years ago, at least globally. See:
http://www.woodfortrees.org/plot/hadsst2gl/from:1979/to:2013/plot/hadsst2gl/from:1979/to:2009/trend/plot/hadsst2gl/from:1979/to:2013/trend/plot/hadsst2gl/from:1997/trend
Paul, thanks for the kind words about my PJM post.
Theo Goodwin says: July 29, 2012 at 6:59 pm
Yes, this sent my irony-meter right off the scale as well! You’d think that Mann would welcome Muller as a long-time kindred spirit on the CO2–>(C)AGW front:
But, alas, it would seem that poor Michael “how dare you question my hockey-stick” Mann has never been able to get past the paragraph that immediately preceded the above December 2003 ‘article of faith’ from Muller:
Source (of this and a number of other “Mullerisms”) at Will the real Richard Muller please stand up
This apparent battle of the over-sized egos calls out for treatment by Josh, does it not?! But in the meantime …
Congratulations to Anthony – who I hope is now taking a much-deserved rest – and his co-authors.
Congratulations, Anthony, Evan, Steve and John. Nice work gentlemen! The 700 comments in less than ten hours says a lot about the speed and breadth of dissemination.
Found in previous comment:
Thanks. In that case,
Forward slash used instead of backward slash in “Figures and Tables”:
1. Pg 3, “Class 1/2 Stations”, Figure 3 (caption on pg 2)
2. Pg 21, Figure 23, “Class 1/2 Stations” and “Class 3/5 Stations” (should be 3\4\5)
Shouldn’t Figure 20 pg 18 use “Class 3\4\5” as that map represents all three binned together?
Wow, just on the first day a ton of crowd-sourced proofreading got done. By tomorrow when people will have actually worked through the paper, maybe some usable peer review.
Why are we still using dead slow dead tree journals for information propagation, when the internet is so much faster and efficient?
Wait… so your big conclusion is that the NOAA doesn’t account enough for urban heat island effect. (Even though here very clearly they do)
http://www.ncdc.noaa.gov/oa/climate/research/ushcn/
http://www.ncdc.noaa.gov/oa/climate/research/ushcn/img/fig2.png
OK so if I’m reading this right you’re saying 0.09°C per decade of the stated increase is false. So instead of the USHCN adjusted values of +1.00C change between 1950 and 2010 (60 years) you’re saying it’s actually +0.54C….
Even if you are correct (which honestly, I am skeptical that such a huge discrepancy could be made) the fact is the warming signal has not been magically whisked away. It’s simply been cut down a notch or two and CO2 remains the only factor that has changed enough to account for that rise in temperature. Nothing else fits the bill, which is what BEST confirms as well.
[REPLY: Read the paper. -REP]
Lucy Skywalker says:
July 29, 2012 at 5:43 pm
Doug Proctor at BH:
Watts’ paper is a get-out-of-jail-free card for every warmist. Based on current knowledge, they have behaved responsibly. Everyone from Al Gore to Bill McKibben has been mislead by the wrong statistical techniques, but, most importantly, not about global warming per se, but the rate of global warming.
Great point. Thanks Doug.
But why did none of them – none of them – check the data in the first place? Was it because the data told them what they all wanted to hear?
Outstanding work!
Thank you.
Here’s are a couple quick questions which I would recommend answering in the full paper:
Was the NOAA systematic upwards adjustment motivated by any known mechanics? Is there any reason to believe that the raw data understates the trend?
Shoulders shuddering with every sob, Bill McKibben is weeping deep into his feculent pillow tonight….
It would be interesting to do a comparison on Canadian weather stations. Here are just two of the weather stations I’ve observed… http://forums.castanet.net/viewtopic.php?f=27&t=33069&p=1301028#p1059079
Nick Stokes (July 29, 2012 at 4:47 pm)
I calculated the 1979-2008 trend from NOAA’s ConUS figures. [link] It came to 0.24 °C/decade.
Nick-
From the data at the link, I get a trend of 0.32 C/decade. With the slightly better (monthly) data from http://www7.ncdc.noaa.gov/CDO/dataproduct , I also get 0.32 C/dec, to 2 digits. So I’m not sure how you got 0.24. However, neither source would seem to be precisely the same as USHCN v2 (adjusted) average, for which Watts et al. report 0.309 C/dec. [This appears to be an ungridded average; figure 18 implies that the gridded average is 0.316 C/dec.]
REPLY – We used two gridding methods: the 26-box method and the 9-region method. the latter produced slightly lower results for both raw and adjusted, but the “gap” between then was about equal. We’ll have to clarify that down the road. ~ Evan
Let me put a scenario. A site, in 1970, is 2km from the ocean. It is a well maintained site, and has remained well maintained, with no concrete etc within 100m, probably still a class one site (if my understanding is correct) However, between then and now, a dense urban area, with factories, lots of vegetation loss, etc, has sprung up between the site and the coast.
How will this affect the measurement of temperatures, particularly in the evening, when the breeze is almost always onshore.?
Is this sort of possible change to temperature readings accounted for?
Is it possible to account or it.?
Anthony et al. –
A suggestion for figures containing multiple parallel plots, as your figure 16 (and others) — please use identical vertical scales on all plots as an aid to your readers. The eye naturally makes a visual comparison between charts, and will be misled if the scales don’t align.
Typo on Page 20 line 387. Should read “Many” instead of “May”
In Figure 20, in the line:
What the compliant thermometers (class 1&2) say: +0.155ºC/decade
The “+0.155ºC/decade” should be in green to agree with the legend.