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.
Why is this not included in references? Thanks
If Anthony Watts is the lead author of this study and Roger Pielke Sr. endorses it, then this is the kiss of death for this study. It could only be worse if Stephen McIntyre or John Christy had any involvement. I’d wait and see if it passes peer-review and anyone is willing to publish it.
It looks very suspicious that Watt’s USHCN study is the odd one out. I imagine it will picked apart quickly when people who know what they are doing look at it. A study was just completed of the USHCN in February 2012. See its findings below.
______________________
“An intercomparison of temperature trends in the U.S. Historical Climatology Network and recent atmospheric reanalyses”
GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L10703, 6 PP., 2012
doi:10.1029/2012GL051387
Russell S. Vose
Scott Applequist
Matthew J. Menne
Claude N. Williams Jr.
Peter Thorne
Key Points
The trend in HCN is comparable to the ensemble mean of the reanalyses
The HCN bias adjustments improve consistency with the reanalyses
HCN and the reanalyses both depict widespread warming from 1979–2008
Abstract: Temperature trends over 1979–2008 in the U.S. Historical Climatology Network (HCN) are compared with those in six recent atmospheric reanalyses. For the conterminous United States, the trend in the adjusted HCN (0.327 °C dec−1) is generally comparable to the ensemble mean of the reanalyses (0.342 °C dec−1). It is also well within the range of the reanalysis trend estimates (0.280 to 0.437 °C dec−1). The bias adjustments play a critical role, as the raw HCN dataset displays substantially less warming than all of the reanalyses. HCN has slightly lower maximum and minimum temperature trends than those reanalyses with hourly temporal resolution, suggesting the HCN adjustments may not fully compensate for recent non-climatic artifacts at some stations. Spatially, both the adjusted HCN and all of the reanalyses indicate widespread warming across the nation during the study period. Overall, the adjusted HCN is in broad agreement with the suite of reanalyses.
http://www.agu.org/pubs/crossref/2012/ 2012GL051387.shtml
Another snip from Pielke, but go over and read the whole thing:
http://pielkeclimatesci.wordpress.com/2012/07/29/comments-on-the-game-changer-new-paper-an-area-and-distance-weighted-analysis-of-the-impacts-of-station-exposure-on-the-u-s-historical-climatology-network-temperatures-and-temperature-trends-by-w/
“Anthony Watt’s new paper shows that a major correction is needed Muller’s BEST study. Anthony also has shown what dedicated scientists can do with even limited financial support. Despite the large quantities of funds spent on the BEST study, it is Anthony Watts and his team who have actually significantly advanced our understanding of this aspect of the climate system. Well done Anthony!”
James – had you read the paper you would have found this quote from WMO:
“The Commission agreed that the publication of the siting classification as a common WMO-ISO standard would help in assessing and improving the quality of data originating from WMO-owned, cosponsored and non-WMO observing networks. The Commission agreed to further develop this classification as a common WMO-ISO standard.”
IPCC apparently has no problems with accepting stuff that hasn’t been peer-reviewed. Maybe Mr. Watts should submit it to a magazine for publication. IPCC should be perfectly happy with that based on their track record.
The comment came from a Globe and Mail poster… named soundoff
How do the conclusions of this study compare with the new study from the BEST people, entitled
“Global land temperatures have increased by 1.5 degrees C over the past 250 years”
http://berkeleyearth.org/results-summary/
and also released today?
I saw a couple of comments up thread asking for information on Klotzbach et al. as pertains to it’s use to estimate what the satellite temperature trends over the lower 48 US states imply about surface temperature trends: bearing in mind that amplification factors, or lack there of, are estimated from models:
http://tropical.atmos.colostate.edu/Includes/Documents/Publications/klotzbachetal2010.pdf
Found that in the GISS model, the global LT amplification over land is about 1.1. This is of course a global figure, and what the factor would be over the US specifically is hard to say. However, I personal must stress that there is no reason to assume that the models get the right amplification factor in individual locations, or even globally (although, if it is even slightly greater than 1, and I do think it is, globally, the Klotzbach et al conclusions would still stand).
Personally, I’m a little skeptical of this paper’s conclusions, as I tend to think that the US data is good relative to that in the rest of the world and has relatively little bias. Still, I think it contributes to the discussion of problems with surface temperature trends.
I’m always interested in boundary conditions. In this case, it appears to be on classification of sites at the 2 vs 3 boundary. The paper indicates that for many sites, the classification was not done on-site, but via photos (especially aerial photographs). There would have been a number of sites where the classification calculation would have been close to the 2 vs 3 boundary. If an error bar was applied to that calculation, how many sites may have moved from the 3 to 2 classification, and would that have a significant impact on the results?
I’m just looking at dotting i’s and crossing t’s type analysis. We all know that one way to discredit a dataset (in this case the Leroy (2010) site classifications) is to find data in that dataset that is clearly incorrect. It is therefore important to show that potentially incorrect classifications around the boundary points will not have a significant impact on the results. This is is something probably for an SI rather than the paper itself.
Unless there are really fundamental errors in this paper, it will be haunting and embarrassing the warmists for years to come.
If this base data for just about everything else is wrong by a factor of two (whether by accident, incompetence or deliberately), then everything else that rests on these foundations needs to be redone. Those who have lost/mislaid/destroyed their original programs, data and notes will find this to be very hard to do. And all those models calibrated against it and their scary conclusions will be shown to be wrong.
The ramifications are nearly endless. Expect a very strong fight from the climatology establishment. They have sinecures and careers and reputations to lose.
Nick,
The 2007 trend from UAH, according to Wikipedia, is .143 degrees C per decade, which matches well with Watts, et. alia paper.
One of the significant points of the Watts et. Alia paper, is that adjustments need to be reviewed carefully.
Regards,
Ed
Congratulations! I also had a problem with a paypal donation using the preset $100 button. I tried it using the “Choose Your Own $ Value” and it worked.
….I can already hear the gnashing of teeth!! Bringing in Stephe McIntyre was brilliant!!
Well done, Anthony! You have put your money (and time away from family, and backbreaking work etc.) where your mouth is!
Cheers, Charles The DrPH
Extremely good question. And getting more and better data (in this case on the data-gathering instruments!) is a great idea.
However, I think you’ll find the paper’s conclusions prove robust. It just makes sense that things would fall out the way they did.
How long will it take for the correct data to be input into data bases operated by such as Wood For Trees?
To Moderator and readers: the post about Vose et al 2012 came from a comment in the Globe & Mail by a poster named “SoundOff”. I wanted only to ask about the reference not his original demeaning comment on Anthony and co-authors but I hit the “send” button too fast, sorry for the confusion.
Watts & Co, many thanks for making your hard work public, still reading whilst fielding nonesense in the UK.
Looking forward to the true “public review” that will now commence.
Thank you
”
‘Charms strike the sight
But merit wins the soul.’
Says Pope and others here
Good on yer, Anthony.
Congratulations on what looks like (on a very quick reading) an excellent contribution to climate science.
One question; you state in the paper:
“Where such discrepancies could not be resolved, or it was determined from photographs, 271 metadata, or curator interviews that the station had been closed or moved after 2002, and 272 prior location could not be established, that station was excluded from consideration and 273 not included in this study.”
How much do you know about how the quality of stations has changed with time (especially ones changed prior to 2002)? If the quality of individual stations has changed over the entire period from 1979 nearly randomly, then you might expect those going from good to bad to have an elevated trend, but also those going from bad to good having a reduced trend. Has this potential source of systematic error been considered? This could be significant if many of the currently good stations were previously bad.
Hu McCulloch said (July 29, 2012 at 4:06 pm)
in reply to Larry’s comment at 1:04 pm “…This was a study of US stations, not world stations, if I read correctly. Be hard to say much about the world from that…”
“…Good point, but USHCN, for all it faults, is one of the best station networks in the world. At least it generally avoids airports. GHCN, GISS, CRU, etc, depend heavily on airports, so that what Anthony has found goes double for them…”
Absolutely. First thing, though is if anyone wants to use GISS, HadCru, or GHCN’s data to refute the facts and conclusions of Watts et al (2012), they’ll have to get them to release their station lists.
Then, they’ll need comprehensive metadata to see exactly how those stations they use would fall under the METEOFrance classifications (approved as the WMO-ISO standard).
From there, they can use those lists and station data with the newer, 2-year old methods (listed as Leroy 2010), to see how the GLOBAL trends show up.
At least, that’s what a REAL scientist would do. They’d want to see if the trends seen using the old methods (and standards) follows through using the new methods (and standards).
Er … not that you aren’t charming as well, Anthony.:-)
[REPLY: I’m sorry, you obviously read the paper, but I’m not entirely sure just what your substantive criticisms are. Must be my poor reading comprehension. Thank you for your insightful analysis. -REP]
JOSH
kadaka (KD Knoebel) says: July 29, 2012 at 3:36 pm
hahahshahahaha spot on
Tucci78 says: July 29, 2012 at 2:00 pm
Zeke says: July 29, 2012 at 3:09 pm
good points
arnoarrak says: July 29, 2012 at 3:32 pm
bluegrue says: July 29, 2012 at 3:06 pm
good to pay attention to issues raised here
I’ve tried to find a definitive answer to this question, but I was unable to so I’m hoping someone else would know.
I’ve been thinking about the TOB adjustment and whether it impacts on this analysis. I understand that Karl et al. 1986 describes how there can be a bias when the measurement 24-hour period does not start/end at midnight, and because temperature observation times changed over the historical period, an adjustment is needed.
However, did the temperature observation time change over the 1979-2008 period? I’m under the impression that the historical change in observation time predates this period, in which case the observations in this period will be consistent in any bias, and hence the bias can be ignored as it won’t significantly impact the trend.
Hopefully someone with more detailed knowledge will be able to comment on whether a TOB adjustment should have any significant impact on the 1979-2008 period, or if it is only relevant when trying to examine trends starting from earlier dates.
Stu says:
July 29, 2012 at 3:18 pm
Lucy says: “Neither eye-for-eye nor sour grapes. It’s martial arts.”
I can appreciate that. I can see it both ways actually. But when commenters were previously so against ‘science by press release’ …
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AHH, but Stu this is not science by Press Release this is a proof reading of the final draft by the over 650 citizen volunteers and their friends. Unlike others with a couple of exceptions, Anthony et al will read these comments and use them to tighten up the paper. Willis and I think Roy Spencer have also used WUWT as a final review for a paper before submitting.
I think it is a great idea. It is very tough to read your own stuff and edit it. This comment by bluegrue @ur momisugly July 29, 2012 at 3:06 pm is an excellent example of what I mean:
Suggestions for headline:-
Settled science? Not any more!
It may not be as bad as we thought it was!
Recent studies throw doubt on Global Warming.
Climate Science stunned. Two plus Two does equal 4!
‘Flip-Flop’ Muller admits that he used to be a Warmist!
Sadly, however, we’re more likely to get this;
The science is settled
It’s worse than we thought
New findings intensify pressure on western governments to act NOW on Global Warming
Ante-Normal mathematics – a resurrected weapon of mass-destruction by climate conservatives?
I’m so much happier now, says Muller, I’ve finally see the light and am enjoying the BEST years of my life. Yup, we are all going to fry!
jimmi_the_dalek says:
July 29, 2012 at 4:57 pm
How do the conclusions of this study compare with the new study from the BEST people, entitled
“Global land temperatures have increased by 1.5 degrees C over the past 250 years”
http://berkeleyearth.org/results-summary/
and also released today?
======================================
They are at odds with each other. Muller was told he wasn’t handling the adjustments properly, but has ignored the people correcting him.
But, in trying to discern which is most believable, consider this. Muller claims his BEST data can tell us what the temps of the globe were 250 years ago. By my reckoning, there were about 10 thermometers we could use for analysis back than, all in Europe. In my view, he loses credibility from that point. I’ve got an image of the GHCN thermometers mapped in 1762…… http://suyts.wordpress.com/2012/07/29/muller-never-was-a-skeptic/