The long awaited surfacestations paper

This summary is from Dr. Pielke at the University of Colorado in his words. I’ll have my own post on some detail not covered here, with links to the SI – data code, etc we are preparing in a day or two. Some may ask why I am not lead author. That was my choice, because the strength is in the statistical analysis, and I wanted it clear that the paper is about that joint work and not about any one person’s efforts. – Anthony

UPDATE: Also, two other posts, by co-author Dr. John Nielsen-Gammon that are must reads are:

The surfacestations paper – statistics primer

Something for Everyone: Fall et al. 2011

Guest post by Dr. Roger Pielke Sr.

A Summary Of Our New Paper “Analysis Of The Impacts Of Station Exposure On The U.S. Historical Climatology Network Temperatures and Temperature Trends” By Fall Et Al 2011

 Our paper

Fall, S., A. Watts, J. Nielsen-Gammon, E. Jones, D. Niyogi, J. Christy, and R.A. Pielke Sr., 2011: Analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends. J. Geophys. Res., in press. Copyright (2011) American Geophysical Union.

has been accepted and is now in press. Below I have presented a summary of the study and its major messages from my perspective.  While the other authors of our paper have read and provided input on the information given below, the views presented below are mine. I will be posting on the history of my involvement on this subject in a follow-up post in a few days.

Volunteer Study Finds Station Siting Problems Affect USA Multi-Decadal Surface Temperature Measurements

We found that the poor siting of  a significant number of climate reference sites (USHCN) used by NOAA’s National Climatic Data Center (NCDC) to monitor surface air temperatures has led to inaccuracies and larger uncertainties in the analysis of multi-decadal surface temperature anomalies and trends than assumed by NCDC.

NCDC does recognize that this is an issue. In the past decade, NCDC has established a new network, the Climate Reference Network (CRN), to measure surface air temperatures within the United States going forward. According to our co-author Anthony Watts:

“The fact that NOAA itself has created a new replacement network, the Climate Reference Network, suggests that even they have realized the importance of addressing the uncertainty problem.”

The consequences of this poor siting on their analyses of multi-decadal trends and anomalies up to the present, however, has not been adequately examined by NCDC.

We are seeking to remedy this shortcoming in our study.

The placement of the USHCN sites can certainly affect the temperatures being recorded—both an area of asphalt (which is warmer than the surroundings on a sunny day or irrigated lawns (which is cooler than surrounding bare soil on a sunny day) situated near a station, for example, will influence the recorded surface air temperatures.

NOAA has adopted siting criteria for their climate reference stations: CRN 1 stations are the least likely to being influenced by nearby sources of heat or cooling, while CRN 5 stations are the most likely to be contaminated by local effects.  These local effects include nearby buildings, parking lots, water treatment plants irrigated lawns, and other such local land features.

To determine how the USHCN stations satisfied the CRN siting criteria and also whether the station siting affected temperature trend characteristics, Anthony Watts of IntelliWeather set up the Surface Stations project in 2007. More than 650  volunteers nationwide visually inspected (and rated) 1007 of the 1221 USHCN stations.  The volunteers wrote reports on the surroundings of each station and supplemented these reports with photographs.  Further analysis by Watts and his team used satellite and aerial map measurements to confirm distances between the weather station sensors and nearby land features.

The Surface Stations project is truly an outstanding citizen scientist project under the leadership of Anthony Watts!  The project did not involve federal funding. Indeed, these citizen scientists paid for the page charges for our article.  This is truly an outstanding group of committed volunteers who donated their time and effort on this project!

Analyzing the collected data, as reported in our paper, we found that only 80 of the 1007 sites surveyed in the 1221 station network met the criteria of CRN 1 or CRN 2 sites – those deemed appropriate for measuring climate trends by NCDC.  Of the remaining, 67 sites attained a CRN 5 rating – the worst rating.  While the 30-year and 115-year trends, and all groups of stations, showed warming trends over those periods,  we found that the minimum temperature trends appeared to be overestimated and the maximum warming trends underestimated at the poorer sites.

This discrepancy matters quite a bit. Wintertime minimum temperatures help determine plant hardiness, for example, and summertime minimum temperatures are very important for heat wave mortality. The use of temperature trends from poorly sited climate stations, therefore, introduces an uncertainly in our ability to quantify these key climate  metrics.

While all groups of stations showed warming trends over those periods, there is evidence to suggest a higher level of uncertainty in the trends since it was found, as one example, that according to the best-sited stations, the 24 hour temperature range in the lower 48 states has no century-scale trend, while the poorly sited locations have a significantly smaller diurnal temperature range. This raises a red flag to avoid poorly sited locations since clearly station measurement siting affects the quality of the surface temperature measurements.

The inaccuracies in the maximum and minimum temperature trends do matter also in the quantification of global warming. The inaccuracies of measurements from poorly sited stations are merged with the well sited stations in order to provide area average estimates of surface temperature trends including a global average.  In the United States, where this study was conducted, the biases in maximum and minimum temperature trends are fortuitously of opposite sign, but about the same magnitude, so they cancel each other and the mean trends are not much different from siting class to siting class. This finding needs to be assessed globally to see if this also true more generally.

However, even the best-sited stations may not be accurately measuring trends in temperature or, more generally, in trends in heat content of the air which includes the effect of water vapor trends (which is the more correct metric to assess surface air warming and cooling; see). Also, most of the best sited stations are at airports, which are subject to encroaching urbanization, and/or use a different set of automated equipment designed for aviation meteorology, but not climate monitoring. Additionally, the NCDC corrections for station moves or other inhomogeneities use data from poorly-sited stations for determining adjustments to better-sited stations, thus muddling the cleaner climate data. We are looking at these issues for our follow-on paper.

However, we know from our study that the use of these poorly sited locations in constructing multi-decadal surface temperature trends and anomalies has  introduced an uncertainty in our quantification of the magnitude of how much warming has occurred in the United States during the 20th and early 21st century.

One critical question that needs to be answered now is; does this uncertainty extend to the worldwide surface temperature record? In our paper

Montandon, L.M., S. Fall, R.A. Pielke Sr., and D. Niyogi, 2011: Distribution of landscape types in the Global Historical Climatology Network. Earth Interactions, 15:6, doi: 10.1175/2010EI371

we found that the global average surface temperature may be higher than what has been reported by NCDC and others as a result in the bias in the landscape area where the observing sites are situated. However, we were not able to look at the local siting issue that we have been able to study for the USA in our new paper.

Appendix- Summary of Trend Analysis Results

Temperature trend estimates do indeed vary according to site classification. Assuming trends from the better-sited stations (CRN 1 and CRN 2) are most accurate:

  • Minimum temperature warming trends are overestimated at poorer sites
  • Maximum temperature warming trends are underestimated at poorer sites
  • Mean temperature trends are similar at poorer sites due to the contrasting biases of maximum and minimum trends
  • The trend of the “diurnal temperature range” (the difference between maximum and minimum temperatures) is most strongly dependent on siting quality. For 1979-2008 for example, the magnitude of the linear trend in diurnal temperature range is over twice as large for CRN 1&2 (0.13ºC/decade) as for any of the other CRN classes. For the period 1895-2009, the adjusted CRN 1&2 diurnal temperature range trend is almost exactly zero, while the adjusted CRN 5 diurnal temperature range trend is about -0.5°C/century.
  • Vose and Menne[2004, their Fig. 9] found that a 25-station national network of COOP stations, even if unadjusted and unstratified by siting quality, is sufficient to estimate 30-yr temperature trends to an accuracy of +/- 0.012°C/yr compared to the full COOP network. The statistically significant trend differences found here in the central and eastern United States for CRN 5 stations compared to CRN 1&2 stations, however, are as large (-0.013°C/yr for maximum temperatures, +0.011°C/yr for minimum temperatures) or larger (-0.023°C/yr for diurnal temperature range) than the uncertainty presented by Menne at al (2010).

More detailed results are found in the paper, including analyses for different periods, comparisons of raw and adjusted trends, and comparisons with an independent temperature data set.

Questions and Answers

Q: So is the United States getting warmer?

A: Yes in terms of the surface air temperature record. We looked at 30-year and 115-year trends, and all groups of stations showed warming trends over those periods.

Q: Has the warming rate been overestimated?

A: The minimum temperature rise appears to have been overestimated, but the maximum temperature rise appears to have been underestimated.

Q: Do the differing trend errors in maximum and minimum temperature matter?

A: They matter quite a bit. Wintertime minimum temperatures help determine plant hardiness, for example, and summertime minimum temperatures are very important for heat wave mortality. Moreover, maximum temperature trends are the better indicator of temperature changes in the rest of the atmosphere, since minimum temperature trends are much more a function of height near the ground and are of less value in diagnosing heat changes higher in the atmosphere; e.g see .

Q: What about mean temperature trends?

A: In the United States the biases in maximum and minimum temperature trends are about the same size, so they cancel each other and the mean trends are not much different from siting class to siting class. This finding needs to be assessed globally to see if this also true more generally.

However, even the best-sited stations may not be accurately measuring trends in temperature or, more generally, in trends in heat content of the air which includes the effect of water vapor trends.  Also, most are at airports, are subject to encroaching urbanization, and use a different set of automated equipment. The corrections for station moves or other inhomogeneities use data from poorly-sited stations for determining adjustments to better-sited stations.

Q: What’s next?

A:  We also plan to look specifically at the effects of instrument changes and land use issues, among other things.  The Surface Stations volunteers have provided us with a superb dataset, and we want to learn as much about station quality from it as we can.

================================================================

UPDATE: Since some people seemed unable to divine the link upstream, the pre-print version of the paper, posted on Dr. Pielke’s website is available here:

http://pielkeclimatesci.files.wordpress.com/2011/05/r-3671.pdf

– Anthony

UPDATE2: Dr. John Nielsen-Gammon, Texas State Climatologist and co-author, weighs in with his post:

Something for Everyone: Fall et al. 2011

As you may have heard, the long-awaited peer-reviewed analysis of the results of the SurfaceStations.org project has finally been released. I can’t wait to see the dueling headlines. Some will argue that the take-home message should be: Poor Station Siting Strongly Effects Temperature Trend Measurements, and will laugh at the idea that we can say with sufficient accuracy what has happened to our climate. Others will argue that the take-home message should be: Poor Station Siting Has No Effect on Temperature Trend Measurements, and will laugh at all the effort expended on a null result. Both sides will find solid evidence for their points of view in the paper. How can that be? How can one paper support opposing conclusions?

Here, in brief, are the answers: The poorest sites tend to be warmer. The minimum temperatures are warming faster at poorer sites than at better sites. The maximum temperatures are warming slower at poorer sites than at better sites. The adjustments reduce the differences by about half. The two effects are roughly equal and opposite so the mean temperature is rising at about the same rate across sites of different quality while the diurnal temperature range shows the biggest difference across sites.

On the one hand, this seems to be confirmation of the quality of the temperature record. All types of sites show the same mean temperature trend, so there’s no change necessary to our estimates of observed historical temperature trends in the United States.

On the other hand, there are several warning flags raised by this study. First, station siting is indeed important for the maximum and minimum temperature measurements. Second, the adjustments are only partly correcting the temperature record. Third, since the adjustments use data from all surrounding stations, there’s the danger that the mean trends are dominated by data from the poorer stations. (Less than ten percent of the USHCN stations are sited well enough to be considered appropriate for climate trend measurements.) Finally, and perhaps most important, are we really so lucky that the rest of the world would also have its poorly-sited stations have erroneous maximum and minimum temperature trends that just happen to be equal and opposite to each other?

Read his full essay here

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tonyc
May 11, 2011 9:25 am

Quick question:
Does the CRN rating take into account potential urban heat island (UHI) effects, or does that just deal with the immediately local site conditions?

Ed Forbes
May 11, 2011 9:29 am

looking forward to reading your paper
congrats on finally getting it out of review

ShrNfr
May 11, 2011 9:31 am

Congratulations to all involved.

Theo Goodwin
May 11, 2011 9:32 am

Could someone give us a backgrounder on the practices of NCDC and NOAA today regarding the recording of temperatures and calculating of trends. Is it the case that they continue to take raw temperature numbers and average them to get daily numbers? If so, which? If so, why? How much of past temperature data is based on averaged numbers? Are trends calculated from averaged numbers?

May 11, 2011 9:32 am

Anthony,
One of the interesting points in Menne et al 2010 was the suggestion that CRN12 sites had a lower rate of MMTS conversions than CRN345 sites. As MMTS conversions are associated with a strong max cooling bias and a moderate min warming bias, this would seem to account for at least some of the effect you note in your paper.
http://rankexploits.com/musings/2010/a-cooling-bias-due-to-mmts/
Congratulations are in order, by the way. I hope to have a chance to follow in your footsteps at some point in the future 😉
REPLY: We have some ideas on that, and will be discussing it in the upcoming post. – Anthony

Mike
May 11, 2011 9:34 am

So I guess this is unfortunately a big…
*YAWN*
REPLY: Well given how much time has elapsed from the time of posting to your comment, I can see how you could come to the snap conclusion without any deeper reading comprehension involved. – Anthony

littlepeaks
May 11, 2011 9:36 am

“1007 of 1221 stations have been examined in the USHCN network.” What happened to the rest?
Also, when published, I hope you will post a link where we can purchase a printed copy of the study.
REPLY: That’s the number of stations that we could positively identify, survey, and that passed quality control. We actually have more stations surveyed since then but at some point your have to stop and move forward. We’ll never get 100% due to some stations being off limits or closed. The hyperlink to the paper (PDF) is in the post, look closely – Anthony

Earle Williams
May 11, 2011 9:37 am

tonyc,
Probably answers in queue already, but just in case…
CRN is a microsite rating only. It does not address the UHI influence on temperature measuring stations.

OK S.
May 11, 2011 9:43 am

Congratulations again on your paper. It was your Surface Stations Project that led me to your site in the first place. I used to follow your progress regularly until you had to stop updating it when “someone” stole your preliminary work to publish his own paper.
One question though. Did the whitewash/paint study ever turn up anything useful?
OK S.

Mike
May 11, 2011 9:45 am

I read the whole post and donated to the paper… FYI
As I see it, the hope was for a classification-dependent over-estimation of the warming effect which doesn’t appear to be happening. The results net out. This would have been a major argument for a UHI-influenced skewing of the US dataset, right? Unfortunately that does not seem to exist, so my YAWN is directed at the (unfortunate) lack of support for this model. It is of course nice to know that the over-estimated mins and under-estimated maxes will help model heat-wave mortality and plant hardiness, but I doubt that result was the hope for this project.
REPLY: Read the paper, the link is in the post above – Anthony

rpielke
May 11, 2011 9:46 am

tonyc – Thank you for your comment. We just examined immediate siting issues. The other effects on the temperature trends, such as from larger scale landscape (e.g. urban), is an issue that also needs to be combined with the siting issue.

Mike Bromley
May 11, 2011 9:56 am

It will be interesting to see the responses once the gravity of this is absorbed (unlike the ‘yawn’ posted above).
Once again, congratulations!

John
May 11, 2011 10:03 am

A question regarding a part of the reportage above on the new paper (and let me add to the congratulations of others to Anthony et al on its publication):
“Q: What about mean temperature trends?
A: In the United States the biases in maximum and minimum temperature trends are about the same size, so they cancel each other and the mean trends are not much different from siting class to siting class….”
This appears to say that although there are errors with important implications for max and min temps, the implications do not include a serious bias in increases in mean temperature.
So my question is, does this mean that the initial testimony by Prof. Muller on the BEST project may be pretty much correct, in that he, too, found increases in mean temperatures that we only a tenth of a degree smaller than the official government version?

May 11, 2011 10:08 am

“Q: So is the United States getting warmer?
A: Yes in terms of the surface air temperature record. We looked at 30-year and 115-year trends, and all groups of stations showed warming trends over those periods.”

My question is, does this study invalidate the published study of Goodridge 1996? His study was confined to California, and results were grouped by county. It concluded there was zero warming in counties with under 100,000 population; essentially rural counties without urban heat island effects. His study period was approximately 1910 to 1998. However, high-population counties showed a 4 degree F increase in temperature over the study’s time frame.
Also, I found that many cities in the U.S. have experienced essentially zero long-term warming by plotting the data released by Hadley Research Center, their CRUT3. Those cities include:
(source: http://sowellslawblog.blogspot.com/2010/02/usa-cities-hadcrut3-temperatures.html)
Montgomery, Alabama
Fort Smith, Arkansas
Little Rock, Arkansas
Fresno, California
Sacramento, California
West Palm Beach, Florida
Jacksonville, Florida
Key West, Florida
Tampa, Florida
Atlanta, Georgia
Des Moines, Iowa
Boise, Idaho
Pocatello, Idaho
Peoria, Illinois
Evansville, Indiana
Dodge City, Kansas
New Orleans, Louisiana
Shreveport, Louisiana
Caribou, Maine
Marquette, Michigan
Columbia, Missouri
Meridian, Mississippi
Asheville, North Carolina
Cape Hatteras, North Carolina
Raleigh, North Carolina
Winnemucca, Nevada
Buffalo, New York
Dayton, Ohio
Oklahoma City, Oklahoma
Pendleton, Oregon
Portland, Oregon
Pittsburgh, Pennsylvania
Charleston, South Carolina
Greenville, South Carolina
Aberdeen, South Dakota
Rapid City, South Dakota
Chattanooga, Tennessee
Nashville, Tennessee
Abilene, Texas
El Paso, Texas
San Angelo, Texas
San Antonio, Texas
Richmond, Virginia
Madison, Wisconsin
Casper, Wyoming

chip
May 11, 2011 10:09 am

Congratulations, Anthony!
I know it will be a temptation on some people’s parts to see not too much here, but I also know that academic papers should be cautious things and you have added considerably to the body of knowledge – never a bad thing. Your results have already added new opportunties for study and shown that people outside academic areas of study have something to offer science. Thanks for all your efforts.
Chip

TomRude
May 11, 2011 10:17 am

As an aside, Let’s notice the worldwide coverage by the MSMedia for the O’Donnell et al. 2011 paper…

upcountrywater
May 11, 2011 10:38 am

I’m looking forward to a coffee table edition, one with big pictures and graphs…
I’m wondering how many of the stations that recorded a state by state record low, are still alive and recording data?

ZT
May 11, 2011 10:45 am

Congratulations to all the authors. (…nice to see the triumphant Arizona station with its own parking lot permanently committed to the scientific literature…). But more importantly, it is nice to see some careful and un-spun climatological research going on. Thank you for your dedication.

stan
May 11, 2011 10:52 am

How much influence have the poor sites had on the temperature adjustments made to other sites?

George E. Smith
May 11, 2011 11:03 am

“”””” Mike says:
May 11, 2011 at 9:45 am
I read the whole post and donated to the paper… FYI
As I see it, the hope was for a classification-dependent over-estimation of the warming effect which doesn’t appear to be happening. The results net out. This would have been a major argument for a UHI-influenced skewing of the US dataset, right? Unfortunately that does not seem to exist, so my YAWN is directed at the (unfortunate) lack of support for this model. It is of course nice to know that the over-estimated mins and under-estimated maxes will help model heat-wave mortality and plant hardiness, but I doubt that result was the hope for this project. “””””
“”””” but I doubt that result was the hope for this project. “””””
So is this how good science is done ? One designs an experiment to prove the validity of some pre-conceived notion ?
I followed the blow by blow revelations of the arrays of barbecue locations, as they were unearthed by Anthony’s mottley volunteer crew. I particularly like the Arizona University example; surely the gold standard of misspent research funds; and so beautifully located right outside the doors of those who are supposed to be experts. That Scientific photograph adorns the entrance to my office cube.
I seem to recall, we all reacted with amazement as the volunteers turned up ever funnier examples of what our tax dollars pay for.
As near as I can discern; the project had no aim; well other than an attempt to log every single station, and let the chips fall where they may.
So Mike; how is it that you were privy to the real intent of this project when Anthony Watts started it. I somehow doubt that Anthony himself knew where it was going; other than to attempt to achieve the above stated objective.
If you do a series of studies to see how far maimed frogs can jump; you will surely find, that if you cut off all four legs, they no longer will jump. Does it matter that you set out to demonstrate that quadraplegic frogs become stone deaf.
I’ll wait to read the published paper, before trying to discern the motives for the project.

Scott
May 11, 2011 11:06 am

How can one paper support opposing conclusions?

Anyone who asks that question and is serious shows how poor science education currently is. And it’s clear from MSM reports of science too…conclusions are often interpretations, not the data themselves. Much of society goes along with those conclusions and assume they’re facts because it fits with their agenda/politics/worldview. Then they get bent out of shape when a critical thinker comes along and questions stuff…
On another note, congratulations Anthony and everyone else involved!
-Scott

Joseph Murphy
May 11, 2011 11:20 am

I believe the temp trend in US sites will be fairly consistent with sites around the world. Sites with artificially warming or cooling should not display a significant trend. If you are taking the max temp of a site that is sitting on pavement that heats up 110F everyday then the trend will be zero. Bad station siting should act as a dampener on trend except for the point at which the artificial heating or cooling started affecting the equipment.

Scott
May 11, 2011 11:25 am

Joseph Murphy says:
May 11, 2011 at 11:20 am
But what if your example site is currently situated on an asphalt parking lot but 60 years was in the middle of a corn field?
-Scott

wayne
May 11, 2011 11:28 am

Roger Sowell says: May 11, 2011 at 10:08 am

Also, I found that many cities in the U.S. have experienced essentially zero long-term warming by plotting the data released by Hadley Research Center, their CRUT3. Those cities include:
—-
I can only speak of Oklahoma City, it has the main airport on the very south side edge with a mainly southerly prevailing wind most of the year. Nothing but fields to the south. It gives us an “energy shield” so to speak. The only trend I find is in the winter minimum readings when the prevailing wind is northerly. That seems to be why it shows no effect from “global warming”. You might check those other cities and exactly where the airports and stations are in relation to the prevailing wind (if they have one) and watch for the trend reversal between maximum and minimum in relation to the seasons, at least here winter is different than the other three. By that simple observation over the years it seems to answer it all, at least in this one case. If the airport and station was on the north edge all of that would change of course.

Craig F
May 11, 2011 11:28 am

Mike says…….
After my first reading of the post and comments it’s hardly a *YAWN* as you so eloquently put it.
I must admit to being a little surprised by the initial findings given that I’d have expected a different conclusion regarding the poor sites. But that’s because I wanted a different conclusion. It does nothing to alter the fact that the sites are poor in the US. Most likely are elsewhere ( anyone got a list of UK sites so I can record some? ) and as a result the past global temperature record as noted from surface stations is not to be trusted and a radical rethink of these sites is needed.
Now. On to read the paper.

Scott Covert
May 11, 2011 11:49 am

Thanks for your hard work Anthony.
Thank you and all the authors for simply stating the results without putting any personal spin or bias. This is what science is supposed to be. Unbiased, open, and fact based.
Your paper adds more information to the debate. It is all wheat and no chaff. Both sides of the AGW debate can use this information without worry over it’s validity.
It may not be a smoking gun but I assume there are none in climate research, just bars of soap carved into gun shapes, covered with shoe polish used to scare the media and the public at large. The Mann Hockey Stick is one such gun, most of the shoe polish is gone from over use and now it only blows bubbles.
REPLY: One of the things we learned is that there are so few well sited stations with long records, and even those have been compromised. There may not even be enough to do meaningful comparisons, but we are doing a follow up paper where we are drilling into the metadata deeper and we may have some additional insight. – Anthony

CRS, Dr.P.H.
May 11, 2011 11:53 am

The history of science is replete with examples of how citizen-scientists have stood up to the established hierarchy of their time & prevailed. Galileo Galilei, Gregor Mendel and other heroes come to mind.
Congratulations and best wishes to you all, this is an incredibly important development with historic implications.

kuhnkat
May 11, 2011 11:54 am

SO………
you computed trends based on either raw data from questionably sited stations or on adjusted data based on questionably sited stations and poorly researched adjustments and the trends are supposed to mean something??
Oh yeah, that doesn’t even start to talk about the spatial coverage of the stations or the idea that you can AVERAGE temperatures from disparate elevations, humidity levels…
CO2 is measured at stations where they control for local anthropogenic and natural sources. When are they going to use the same schema for temp background??? In other words, if I am trying to find the average temperature of my house, I am NOT going to site thermometers next to heater ducts or elements, light bulbs and computers on all day…
Are y’all trying for a spot on AR7????

Jeremy
May 11, 2011 12:00 pm

So, how long until the backstory of peer-review obstruction comes out?

Alba
May 11, 2011 12:00 pm

Help!! I seem to be having hallucinations. Last night I thought I read a post on WUWT which claimed that the Vatican was getting involved with the issue of climate change. I thought that I read lost of comments on the post. Then I thought that I put a comment on myself. Duh! When I went to see if my comment had been accepted I found no mention of anything to do with the Vatican. The post I thought I had read just wasn’t there. Is there a cure for thinking that you have read non-existent posts on WUWT?
REPLY: It simply scrolled off the main page, down at the bottom note this:
← Older posts
Click on that or use the search box for “vatican” – Anthony

1DandyTroll
May 11, 2011 12:02 pm

So, essentially, disregarding that you guys just give more proof that climate is poorly manipulated statistics at best, the climate hippies will, of course, just deny it still.
Heck of a job though.

DR
May 11, 2011 12:10 pm

Congratulations, Anthony et al.!
Just one question – Table 1, Class 2, should it be “No artificial heating sources within 30m.” ? (i.e. less than 100m but more than 30m?)

Alec, aka Daffy Duck
May 11, 2011 12:24 pm

Congrats! and.. it went up on DIGITAL JOURNAL 15 minutes ago:
Widespread Flaws in Weather Stations Networks Used to Track National Temperature Trends, Says New Study
Read more: http://www.digitaljournal.com/pr/305726#ixzz1M4cLfrG7

Milwaukee Bob
May 11, 2011 12:41 pm

Congratulations Doc, (and ALL volunteers) on getting your Baby birthed. And a right cute thing IT is!

40 shades of green
May 11, 2011 12:43 pm

Congrats.

Alan
May 11, 2011 12:45 pm

Suggestion/question: would it be possible to block any submissions for comments on a post in, say, the first 15 or 20 minutes of its posting? (Then maybe some people would take the time to read and digest the actual article before reacting often too quickly.)

Engchamp
May 11, 2011 12:46 pm

I was going to say “good post” or something akin.
However, I have been diverted by…
1DandyTroll says:
May 11, 2011 at 12:02 pm
“So, essentially, disregarding that you guys just give more proof that climate is poorly manipulated statistics at best, the climate hippies will, of course, just deny it still.
Heck of a job though.”
I would suggest that comment is one heck of a tautology.

Richard S Courtney
May 11, 2011 12:57 pm

Excellent! Congratulations to all involved.
And, as is usual with the most interesting of studies, the findings are not what anybody could have predicted.
Are the findings typical of sites worldwide? Perhaps and perhaps not, so reason form more study: i.e. another indication of good science.
Thankyou.
Richard

Stephen Brown
May 11, 2011 1:07 pm

I have had insufficient time to read thoroughly the entire paper but what has impressed me above all else is the fact that the paper depends entirely on observed and observable data.
That is exactly where the scientific emphasis should be.
BRAVO to you, Anthony, and to your veritable army of grant-free volunteers. Together you have garnered data sufficient for many more studies, all of which, it is to be hoped, will be carried out in the true scientific process.
This is truly a job well done!

Ralph
May 11, 2011 1:13 pm

I know you have spent a lot of time on this Anthony, but could you explain more how the max temperatures of poor sites can be considered to be not quite as high as expected. If I have a monitoring station with a ruddy great Trent 900 ( jet engine) pointing at it, I am going to get a higher temperature. So how do such poorly sited stations end up with lower trends?
.

Wellington
May 11, 2011 1:16 pm

Congratulations, Anthony and all.

May 11, 2011 1:28 pm

Congrats Anthony.
Let me recap my long held position on all of this.
The question of bias in the temperature record comes down to three fundament issues.
1. Microsite bias. ( climate near the ground– see geiger to start your education folks)
2. UHI– see Oke to start your education.
3. Bias due to sampling issues. no real canonical text to start with.
1. Microsite bias. By looking at the original field studies on microsite ( performed by Dr. LeRoy’s associate) and by looking at all the studies to date -JohnV, myself, menne, and now Fall et all, we can find no substantial microsite bias that SKEWS the MEAN global temp up or down. This was exactly as some of us expected. Early studies showed the effect, if present at all, was small or within the noise floor. We should also reconize that IF microsite was LARGE we would see discrepencies (large discrepencies) between UHA and say CRU or GISS. That is, the microsite bias, if it existed, would be SMALLER than the differences we see between UHA and CRU or GISS. What about the ROW (rest of the world)? As a pure research project and as a QA exercise I think it makes sense to survey stations around the world. But you cannot expect to find anything different than you found in the US. You can expect to find pretty much the same thing.
2. Mesoscale /UHI. to date the studies done on UHI ( with the exception of Imhoffs recent work) have not taken advantage of up to date Satillite products. A few people are walking down that path; Muller and others I won’t mention. The key datasets here are the ISA data set and the MODIS 500m dataset. Classifying urban and rural is a key uncertainty. However, do NOT expect to find a UHI signal that exceeds .15C.
The small size of the UHI signal must be taken into account in your DOE. if your DOE does not recognize the small effect size, you won’t find the signal. Further, to date all studies have one major failing. They tend to focus on identifying urban by proxies that are not tied to the major causes of UHI. We can look at the causes like so.
1. Disruption of the boundary layer. That is, tall buildings. 3D imagery will be required to classify sites by this.
2. Land use/type AROUND the urban site. Especially water use. Also the building
of dams can transform the weather at Rural sites. That needs to be controlled for.
agri use is also critical
3. Heat capacity changes when rural is transformed to urban.
Those physics are far more important to capture than proxies like population and night lights. In the end, UHA temperatures should lead us to believe that the meso scale bias is small. But, that’s important to quantify.
Bias due to sampling. This is a misunderstood topic. We have no reason to believe that sampling biases the answer. It may however impact our certainty.
The other issue here is the whole historical metadata issue.
In the end, folks will find that the temperature records are sound. Not perfect, sound.
What’s that mean? Well it means that we are coming out of an LIA. It was colder in the past. The world is getting warmer. Our estimate ( say .8c) is pretty darn good considering all the warts in the data and data collection.
The REAL questions are
1. what uncertainty bounds do we put around that number.
2. how MUCH of the .8C is due to changes we have made to the atmosphere?
It has gotten warmer. Some of that is of course natural variability(sun and ocean cycles) . A small part of that may be UHI bias. and some of that, physics tells us, is due to GHGs.
You want a debate IN climate science, that is where the debate is.
If you want to argue that 100% of the .8c is UHI, you’re not in the debate
If you want to argue that it is all the sun, you’re not in the debate
If you want to argue that GHG is ALL of it or NONE of it, you’re not in the debate.
So one way to get the debate you want is to put your numbers down.
1. UHI ( ~.1c)
2. NV ( ~.3c)
3. GHG (.4c)
or any such thing, subject to some constraints.
1. UHI ( ~.8c)
2. NV ( ~.0c)
3. GHG (.0c)
That is not a position that can be defended. So, its not a part of the debate.

James Sexton
May 11, 2011 1:42 pm

Congrats guys! On the road, so I won’t have time to read and digest the paper for a few days. WTG!!!

Snowlover123
May 11, 2011 1:43 pm

I hope that this will be the last time I hear from an advocate “he’s not a climatologist so his opinion is garbage” etc.
I am quite impressed at the authors of this skeptical paper. Not one, but two State Climatologists with PhDs co-authored this paper.
We also have prominent scientists Dr. Souleymane Fall, Robert Pielke Sr. and Dr. John R. Christy, a climate scientist.
And of course we have Anthony Watts!! 🙂

Rob Honeycutt
May 11, 2011 1:47 pm

Yes, congratulations on confirming that all the data sets we’ve all been looking at for so long are not in error. We all appreciate that.
REPLY: Congratulations on the typical non thinking snark response. You obviously didn’t read the paper. – Anthony

Rob Honeycutt
May 11, 2011 2:07 pm

Anthony… I have read the paper and your comments and Dr Pielke’s comments. In their entirety.
REPLY: Really? Must be a snark problem then, because your answer had nothing but that in it. – But it is typical for your track record here. Of course you would have snarked no matter what the paper said. We still don’t know the magnitude of the combined effects, but we’ll have more in the second paper. – Anthony

Rob Honeycutt
May 11, 2011 2:12 pm

I mean, how much more clear can it be?….
“…In the United States, where this study was conducted, the biases in maximum and minimum temperature trends are fortuitously of opposite sign, but about the same magnitude, so they cancel each other and the mean trends are not much different from siting class to siting class.” [emphasis added]
REPLY: Ah you missed a whole bunch, but that’s OK , here ya go, from the Texas State Climatologist:
On the other hand, there are several warning flags raised by this study. First, station siting is indeed important for the maximum and minimum temperature measurements. Second, the adjustments are only partly correcting the temperature record. Third, since the adjustments use data from all surrounding stations, there’s the danger that the mean trends are dominated by data from the poorer stations. (Less than ten percent of the USHCN stations are sited well enough to be considered appropriate for climate trend measurements.) Finally, and perhaps most important, are we really so lucky that the rest of the world would also have its poorly-sited stations have erroneous maximum and minimum temperature trends that just happen to be equal and opposite to each other?
So if you thought that the temperature record in the US was lousy, well for mean temperatures in particular it may not be too bad. (Note: regional conditions may vary.) And if you thought that the adjusted station data had eliminated effects due to poor siting, well for most temperature variables there’s still a ways to go. I’m glad we now have the Climate Reference Network, which should at least guarantee accurate trend measurements going forward.
– Anthony

Rob Honeycutt
May 11, 2011 2:22 pm

Look, Anthony, it’s just as valuable in science to show what doesn’t have an effect as does an effect. In that you’ve done something very valuable. Enjoy it! But I think Pielke’s words are pretty clear here. Station siting quality has no effect on mean trends. Same thing that Muller said. Same thing every other study has said.
Honestly, I’m not trying to be snarky. I congratulate you! I’ve never had my name show up on a scientific paper. Now you have. It’s a great thing. Celebrate it!
REPLY: Ok I’ll give you the benefit of the doubt, thank you, your post appeared to be snark. Bear in mind this is just one analysis, once we drill deeper we’ll know more. One of the big problems witht eh network is that even the best stations are not free from problems, for example the majority of “best sited stations” are at airports, with different equipment. Most of the long term stations with original equipment have been done away with, which is why this project took so long. We wanted to find all of the best stations if possible, there was a plethora of bad ones, dime a dozen. But in reality, no station has gone untouched by change of some sorts. Even the station in Mohonk, NY which is touted as “one of the best” has problems.
Note that Neilsen-Gammon thinks the bad stations may still be swamping the good ones. – Anthony

Rob Honeycutt
May 11, 2011 2:39 pm

But I then need to ask… Do you believe this will, in any way, alter the big picture in climate science related to what is happening with global climate?
REPLY: It may, what we are trying to quantify is how much of the 0.7C to 0.8C trend in the last century is from: natural variation, GHG’s, and other biases (siting, UHI, land use change, equipment change etc.). Once we get closer, we’ll know how much of an impact there is. – Anthony

rpielke
May 11, 2011 2:39 pm

Steven Mosher –
1. Mesoscale and regional land use have a clear significant impact on multi-decadal surface temperature trends. This is much more than the UHI or local effect. For just two examples see our papers
Fall, S., D. Niyogi, A. Gluhovsky, R. A. Pielke Sr., E. Kalnay, and G. Rochon, 2009: Impacts of land use land cover on temperature trends over the continental United States: Assessment using the North American Regional Reanalysis. Int. J. Climatol., DOI: 10.1002/joc.1996.
http://pielkeclimatesci.wordpress.com/files/2009/08/r-329.pdf
Montandon, L.M., S. Fall, R.A. Pielke Sr., and D. Niyogi, 2011: Distribution of landscape types in the Global Historical Climatology Network. Earth Interactions, 15:6, doi: 10.1175/2010EI371
http://pielkeclimatesci.files.wordpress.com/2011/02/r-344.pdf
2. The interpretation of surface temperature trends is made more difficult (i.e. less certain) if there are concurrent trends at the same location in humidity; e.g. see
Davey, C.A., R.A. Pielke Sr., and K.P. Gallo, 2006: Differences between near-surface equivalent temperature and temperature trends for the eastern United States – Equivalent temperature as an alternative measure of heat content. Global and Planetary Change, 54, 19–32.
http://pielkeclimatesci.wordpress.com/files/2009/10/r-268.pdf
Fall, S., N. Diffenbaugh, D. Niyogi, R.A. Pielke Sr., and G. Rochon, 2010: Temperature and equivalent temperature over the United States (1979 – 2005). Int. J. Climatol., DOI: 10.1002/joc.2094.
http://pielkeclimatesci.wordpress.com/files/2010/02/r-346.pdf
3. There is clear divergence in time between the trends at the surface and in the lower troposphere with the warming trend, as diagnosed by the dry bulb temperature, significantly higher at the surface; e.g. see
Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2009: An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841.
http://pielkeclimatesci.wordpress.com/files/2009/11/r-345.pdf
4. The use of the minimum temperature to assess trends is made more difficult since it is typically a significant function of height above the gound even over a few meters; e.g. see
Steeneveld, G.J., A.A.M. Holtslag, R.T. McNider, and R.A Pielke Sr, 2011: Screen level temperature increase due to higher atmospheric carbon dioxide in calm and windy nights revisited. J. Geophys. Res., 116, D02122, doi:10.1029/2010JD014612.
http://pielkeclimatesci.files.wordpress.com/2011/02/r-342.pdf
These are just four issues, in addition to the siting issues, that raise questions on the “soundness” of the surface temperature data and on the interpretation on the observed trends. That we found systematic biases in both the maximum and minimum temperatures in our new paper alerts us that the absence of a bias in the mean is fortuitous, as this is not a random sampling error.

rpielke
May 11, 2011 2:47 pm

Rob Honeycutt – Thank you for your comments.
You wrote “But I think Pielke’s words are pretty clear here. Station siting quality has no effect on mean trends.” This is misinterpreting what we found. There is a statistically significant bias in the both the maximum and minimum surface temperature trends. They are of opposite in sign such that there is no statistically significant difference in the mean surface temperature.
If you want to think of these systematic biases at the poorly sited locations as errors, two errors do not create an accurate estimate. Also, our finding that using the best-sited stations, the diurnal temperature range in the lower 48 states has no
century-scale trend, while the poorly sited locations do, further emphasizes that the lack of a trend in the mean is not a robust result in general.

Stephen Rasey
May 11, 2011 2:48 pm

Is there an assumption that if a station is a Class 4 today, it has always been a Class 4?
Hypothesis: Suppose a station that is rated today as a Class 3 or 4 or 5 was originally setup properly as a Class 1 or 2? The assumption being that overtime, the siting quality of the station deteriorates as roads get paved, irrigation and A/C systems get installed. Would such a station show a materially different trend over its history?
Are there non-zero mean offsets in the minimum, maximum and means by Class compared to Class 1?

REPLY:
We believe it would, the problem is that the metadata is quite incomplete. – Anthony

Scott Covert
May 11, 2011 2:49 pm

For myself, the paper gives me more confidence in the temperature record. The data isn’t perfect but if you can extract small signals like biases from CRN ratings that have logical causes and effects, the signal to noise ratio must be pretty good and the data isn’t hopelessly corrupted IMO.
This is a good feeling. I am a skeptic but keeping an open mind is critical and I welcome hard data that changes my perspective. If you can’t change your opinion, you are pig headed and a fool.
Even though this study does not reinforce my position on AGW, I accept it and have a better understanding of the debate having read it.
I believe we humans are adding a significant amount of CO2 to the atmosphere but I don’t think the warming caused by it is. Yes it is believable that CO2 warming exists but I am not convinced it has a real measurable effect above the random background noise.
Rob Honeycutt, do you have evidence beyond GCMS or statistical manipulations that might convince me I am wrong? Hard data, experimental data, or at least some sort of logical argument I can follow?

Brian D
May 11, 2011 2:57 pm

Good job fellas! Still would like to see us use the best stations to monitor climate trends though.
The warming climate is not so unusual for some areas, as it is for others. MN has seen it this warm before back in the 30’s and 40’s. Just pull up 100+ yr stations in the GISS charts and you’ll see what I mean.
Regional changes are what is important, and are those changes unusual for that region. And if so, why?

John
May 11, 2011 3:03 pm

To Steve Mosher (1:28):
You nailed it pretty well when you said this:
“So one way to get the debate you want is to put your numbers down.
1. UHI ( ~.1c)
2. NV ( ~.3c)
3. GHG (.4c)”
I would add two things.
(1) The satellite record, for the last 30 plus years, shows a slighly smaller rate of temperature increase, than for land-based records. That should be accounted for as well. Could we would be talking about 0.7 degrees warming, not 0.8, when the dust settles? It doesn’t seem like a lot, but it means there is less warming for various sources to explain. On the other hand, if the slight discrepancy is due to the satellite record being relative immune to UHI effects, then your first point already captures satellite data differences from the land record.
(2) It isn’t just GHGs, but all anthropogenic emissions. So you have to add in the warming from increased methane and black carbon and tropospheric ozone and the cooling from increased sulfate. I don’t know how they balance out over the past century, but they influence temperatures and we can’t ignore that.

Stephen Rasey
May 11, 2011 3:03 pm

RE: “ Metadata is quite incomplete
No doubt that it is. However, there may be opportunity for some data and/or physical experiments on how big the problem might be. It could serve as a boundary criteria; “it could be this much, unlikely to be more.”
Steven Mosher: Put me down for:.
1. UHI ( ~0.4 to 0.6 c)
2. NV ( ~ balance)
3. GHG (~.1 – .4 c)
Given where the data is coming from, UHI is more than half the perceived signal.

1DandyTroll
May 11, 2011 3:23 pm

There’s one thing I don’t understand (yes well haha just hold on to yer pants for decency ) what is that actual goal of the study?
If the goal was to make a show of how ridiculous the climate hippies hubris at trying to correct “faulty” readings is, then you succeeded, I say. But if your goal is to further the knowledge of man in some other aspect it would be real nice if you guys could make a separate post where you explain it exclusively for that purpose for the rest of us normal geniuses. 😉

TA
May 11, 2011 3:39 pm

“rpielke” mentions:
“…our finding that using the best-sited stations, the diurnal temperature range in the lower 48 states has no century-scale trend, while the poorly sited locations do….”
Wouldn’t that be a good headline? The fact that the two errors cancel each other out would seem to corroborate the temperature record, but assuming I am understanding this correctly, if the daytime trend comes only from poorly sited stations, that would tend to discredit the temperature record.

u.k.(us)
May 11, 2011 4:08 pm

Rob Honeycutt says:
May 11, 2011 at 2:39 pm
But I then need to ask… Do you believe this will, in any way, alter the big picture in climate science related to what is happening with global climate?
=========
I might ask the same of yourself, regarding current policies to mitigate AGW , which of course is what the debate is all about.

Konrad
May 11, 2011 4:09 pm

Anthony, congratulations to you and your fellow authors for getting through the peer review process. Although I suspect that if ” Minimum temperature warming trends are overestimated at poorer sites” made it into press, your more adversarial reviewers may have been asleep at the wheel 🙂
http://digitalcommons.unl.edu/bioscifacpub/150/
http://www.met.sjsu.edu/~wittaya/journals/LargeScaleWarmingIsnotUrban.pdf
http://www.metoffice.gov.uk/hadobs/urban/Parker_JClimate2006.pdf

EternalOptimist
May 11, 2011 4:10 pm

As a layman, one thing springs to mind. If the history of instrument measurments is so flakey, as you have proven, who in their right mind would use a proxy ?
EO

May 11, 2011 4:11 pm

Stephen Rasey says:
UHI ( ~0.4 to 0.6 c)
Well lets review what we actually know. If UHI is that large, then what?
First a bit of logic. The land is 30% of the planet. The ocean is 70%.
Lets assume you were correct as do some simple math. I’ll just use some
approximate figures and people can look up more accurate figures to get a handle
on things.
Land = ~1C
Ocean = ~ .7C
1*.3 + .7*.7 = ~.8C
Now, you think that as much as .6C of the Land is Bias
Land = .4C
Ocean = .7C
PROBLEM. we know that the air over the land is generally warmer than the temp of the 1 meter of water.
PROBLEM. we know from satillites (UHA) which measure the troposphere that UHI
cannot be this big.
PROBLEM. even a pristine all rural dataset of land sites shows more warming that this.
PROBLEM. even IF it was this bad you get the following.
.4*.3 + .7*.7 = .6C of warming as opposed to .8C of warming
If you look at all the studies done the highest figure for UHI is around .3C, The lowest figure is 0, Jones figure is .05C.
based on what we know, a figure between 0C and .3C is consistent with our best knowledge. With a substantial amount of work I would NOT accpet a figure outside this range. Put it this way, if it were bigger than .3C you would see it in UHA.
we dont.

May 11, 2011 4:15 pm

“(1) The satellite record, for the last 30 plus years, shows a slighly smaller rate of temperature increase, than for land-based records. That should be accounted for as well. Could we would be talking about 0.7 degrees warming, not 0.8, when the dust settles? It doesn’t seem like a lot, but it means there is less warming for various sources to explain. On the other hand, if the slight discrepancy is due to the satellite record being relative immune to UHI effects, then your first point already captures satellite data differences from the land record.”
Yes, so a few years of looking at this puts me squarely in the camp that UHI could be
on the order of .1C to .15C.. or about TWICE what Jones estimated. Anything bigger than that would be easily detected.
here is the thing. the SMALLER the UHI effect is, the BETTER your criteria for separating urban from rural needs to be. Think about that. when we divide stations into rural and urban that categorization will have error. The bigger UHI is, the less important that screen is. the smaller UHI is, the more important that screen is

geo
May 11, 2011 4:16 pm

Well done to all involved, and particular congratulations to Anthony and Evan for having completed this leg of the journey.
Personally, I have always said that even if surfacestations.org proved that station siting had zero impact on the record, *it would have been no less worthy a project than if it showed problems* (as apparently it has). You can’t know until you know, and it was blindingly obvious in 2007 that there was utterly *no* reason to have confidence.
I mean no disrespect (in fact, exactly the opposite) when I say that I’m also confident that this group of authors are only the first and not the last to slice and dice this data in ways that will be fruitful to our understanding of the climate record.

Manfred
May 11, 2011 4:18 pm

@ Anthony Watts and Steve Moscher
@Anthony,
I wonder if the methology is capable of addressing the global mean temperature issue:
1. Station siting has an influence on absolute temperatures, but when it comes to temperature trends, small alterations around 1/2 classified station have a similar effect on trends as big alterations around 3/4/5 stations (see for example the effect on trends caused by population increase). We may then see the UHI / land use change effect on trends equally spread among all categories but still not quantifiable.
2. The US data shows the warmest year in 1934 what is rather atypical. Further, according to McIntyre, the GISS UHI correction appears to be working reasonably well in the US, while it fails anywhere else (because there are as man upwards as downwards corrections). This may limit the validity of these results on the 98% rest of the earth’s land area.
,
Microsite bias: You probably meant UAH and not UHA. UAH lower tropospheric trend should be significantly higher than ground based trends (according to all climate models). If it is not, climate models have problems not only with the complexity of climate but the basics as well. It may be more likely, that ground based trends are inflated.
Mesoscale/UHI: Your 0.15 deg guess doesn’t agree with various papers by McKitrick, Pielke and others and again with UAH data.
Sampling: No issue with that.
Summary lacks of the uncertainty arising from sea surface data. Land data contributes on 1/3, and the really big data adjustments – up to the order of the whole warming – have been done on sea surface data.

LazyTeenager
May 11, 2011 4:20 pm

It is claimed that the minimum temperature trend and maximum temperature trend cancel out “fortuitously”. That is an assumption that should be tested. I think that there is a reason for it.
So it’s time to do an experiment instead of relying on mistaken common sense. Build two weather stations side-by-side. One perfect and the other with asphalt and run both for a year. See then if the max and min trends cancel out.

May 11, 2011 4:38 pm

Re Steven Mosher defining the terms of the debate:
I find it quite interesting that there is an “accepted” warming of 0.8 degrees C (or 0.7 or any other number) during the past century, when so very many temperature records show zero warming. It is highly unlikely that a multitude of temperature records, from different locations across the USA, would all be unaffected by GHG, if there is a GHG effect. And yes, I’ve read and understand the “physics” argument for GHG warming. I don’t agree with it for reasons I’ve explained before.
It is a strange physics that allows a CO2 effect to be non-existent in some cities or other locations but not all such locations.

Stephen Rasey
May 11, 2011 4:42 pm

Anthony, I think you should add a internal link to the Gibbas 2011 paper
An Investigation of Temperature Trends from weather station observations representing various locations across Utah (21.5mb PDF) by Mark Gibbas
http://wattsupwiththat.com/2011/04/04/an-investigation-of-ushcn-station-siting-issues-using-a-cleaned-dataset/
It is a good compliment to yours. You address station Class. Gibbas brings up Land use and changes in land use over time and its affect on temperature records. They are certainly related, but different in the dimension of study.

Stephen Rasey
May 11, 2011 5:37 pm

steven mosher says: May 11, 2011 at 4:11 pm
I have to agree with Roger Sowell. Steven Mosher, is using uncertainty bands far too narrow. And frankly, I think I let him bully me into a UHI high side as low as 0.6. The problem is that his 0.8 deg C overall has lots of uncertainty to and I let him frame the question.
In his reply to me, he takes it as a given that the Oceans have warmed 0.7 dec C. Yea, like we have 100 year temperature records from a well sampled space of the ocean surface. Sorry Steven, just because you say so, doesn’t make me believe it.
You want to show me a link to a non-IPCC report that supports 0.7 deg +/- 0.0 ocean warming, I’ll look it up. Meanwhile, the first link I found was this: http://www.worldclimatereport.com/index.php/2007/05/14/questioning-ocean-warming/ which tells me the data is far less certain.
WUWT ENSO pages http://wattsupwiththat.com/reference-pages/enso/
don’t make 0.7 deg C / century ocean Warming a slam-dunk either.
I don’t deny that temperatures and sea level can move up and down. I’m a geoscientist. Climate change has been going on for 4 billion years without the hand of man involved.
For instance, here is an interesting paper about paleo coastal fossil dunes in NZ.
Disappearing beaches: hydro dams and rising seas
by Dr J Floor Anthoni (2000)
http://www.seafriends.org.nz/oceano/beach.htm
with a very interesting sea level chart on:
http://www.seafriends.org.nz/oceano/beachdam.htm
This chart is titled
Mean Sea Level and Tropical Temperature
over the past four ice ages.
The X-axis runs from 300 Kya to 0
The Y -axies data ranges are Temperature 22 to 29 deg C
and mean sea level (-100 m to +100 m)
but here is the kicker:
The reference is “After Fairbridge 1961 and Zeuner 1959”
about 15 years before Vail et al from Exxon published their eustatic curves.
Here is a link to a Fairbridge bio:
http://www.lavoisier.com.au/articles/greenhouse-science/solar-cycles/RichardMackeyForum2008.pdf

May 11, 2011 5:48 pm

I think what you did is very good Anthony. You seem to have eliminated the UHI and instrument error as major players in the game. That is huge. Simplification is always good.
I also think if you compare the warming trend from the 1910’s to the 1940’s with the warming trend from the 1970’s to 2000, assuming that the earlier trend is natural and the slope of the later trend was possibly caused by CO2, the difference in the two slopes indicate that CO2 contributed very little. Almost the entire temperature increase can be attributed to natural cycles.
REPLY: The study didn’t look at instrumentation error at all, so your conclusion is not part of the paper. – Anthony

Bill Illis
May 11, 2011 5:52 pm

Congrats Anthony et al.
I guess this answers a few questions, mainly why other groups were finding the mean didn’t change much between CRN 1 and 5 for example, when that seemed implausible. This answers why that is so a little better.
But then, there ARE differences between the classifications and in the unadjusted raw data versus the adjusted data ( by classification) which are puzzling. For one, I wouldn’t have expected the TOB adjustment to be so large since 1980 (maybe 1920 but not 1980).
There are larger differences in the data since 1895 (which is not particularly highlighted unless one reads the whole paper very carefully). I think there is alot of veiled references which the peer-review probably required that are evident. It is a little hard to tell since the draft paper in this form is not really clear which are the data shown in Figures 4,5,6,7,8,9,10,11,12.
Generally, I think the spin will be that there is not as much difference in the station ranking as the actual data shows. Getting it published probably required this so I await the follow-up studies. I note that a 0.3C is quoted in the conclusion.

Latitude
May 11, 2011 6:16 pm

Roger Sowell says:
May 11, 2011 at 4:38 pm
It is a strange physics that allows a CO2 effect to be non-existent in some cities or other locations but not all such locations.
=======================================================
Roger, do you know where Woodfortrees gets their temp data?
It’s confusing to me that almost without exception, every state you pull up shows a negative temp trend.
For example:
Alabama
http://stevengoddard.wordpress.com/2011/05/11/90-years-of-cooling-in-alabama-led-to-the-disastrous-tornado-outbreak/#comments
Georgia
http://stevengoddard.wordpress.com/2011/05/11/global-warming-ravishing-newts-home-state/#comments
and of course, the old press releases contradict everything they are trying to say now:
Date: January 29, 1989 Publication: Austin American-Statesman
WASHINGTON – If there is a global-warming trend, it has not shown up in records of the average annual temperature of the United States going back to 1895, according to researchers at the National Oceanic and Atmospheric Administration.
So what gives?

Latitude
May 11, 2011 6:21 pm

steven mosher says:
May 11, 2011 at 1:28 pm
So one way to get the debate you want is to put your numbers down.
1. UHI ( ~.1c)
2. NV ( ~.3c)
3. GHG (.4c)
=====================================================
No mosh, to get the debate I want is to start with the truth
1. LAPT (lied about past temperatures) (~.4c)
2. APTD (adjusted past temperatures down) (~.4c)
3. MAT (makeup Arctic temperatures) (~.4c)

James Reid
May 11, 2011 6:53 pm

mosher
“You want a debate IN climate science, that is where the debate is.”
As a layperson who has now read quite a bit in this area I am impressed with your summary of this part of the debate IN climate science… but surely the other really important part of the debate is the question of “CO2 forcing”?
If we (in Australia) are being asked to wear a “Carbon Tax” must the question of CO2 forcing not be central to our concerns? I take note of Drs. Richard Lindzen and Bob Carter on this matter (amongst others).
Great science Anthony and others. I look forward to further analysis of the data.
I would like to help with a similar survey of weather recording sites in Australia if that is going to occur. My first problem is knowing how to locate “official” sites in Australia that are used for the various global temperature data sets… can anyone set me on the right path?

May 11, 2011 6:59 pm

The “trend” of siting quality seems to be the dominant “forcing driver”. I.e., it gets worse as time goes on, mainly through urban encroachment — exacerbated most recently by disingenuous “adjusting” of records.

Fred Peterson
May 11, 2011 7:06 pm

A heat sink has these properties ie reduces variability, make coldest- warmer and hottest- colder. Is this not the case with buildings and artificial ground surfaces. The analysis performed appears to confirm this. The question comes back to how it affects the mean. If the diurnal variation is even then it probably doesn’t.
I suspect if this “hypothesis” is true we will find similar effects if the same data analysis is performed world wide (all other things being equal).
The next issue is then if the weather or climate or whatever has more variability (for whatever reason) we could put in an argument for it is both getting hotter and colder at the same time. As we know cherry picking data to strengthen a point is easy to do.
So is the mean daily temperature averaged over time the correct number to choose. I think the majority of “persons in the street” would say yes (a concerted effort to stop reporting of simplistic cherry picking data is required).
So we then come back to the $64 question if the mean temperature is rising how much is attributable to man made CO2.

Robert Morris
May 11, 2011 7:13 pm

Can I just query my understanding (or not)?
My interpretation is that the best and worst sited weather stations have their own inherent biases which the research has highlighted and although from a superficial averaging they cancel each other out, this would be a misunderstanding of the data.
Rather, the fact that the best and worst each have biases means rather than canceling them out they compound the uncertainty of any trend. In effect the margins of error are now expanded and the concept of a measured or understood trend in US temps is now demonstrably more moot than previously considered?
Is that roughly right, accepting gross oversimplification?

May 11, 2011 8:28 pm

Congratulations.
“even the best-sited stations may not be accurately measuring trends in temperature or, more generally, in trends in heat content of the air which includes the effect of water vapor trends. Also, most are at airports, are subject to encroaching urbanization,..” Most of the best-sited stations are at airports????
Twenty six years ago I first heard the term, “airport effect” as a cause of most of the measured warming.
So the study really didn’t address land use. This is a point that needs to be made.

Rex
May 11, 2011 8:58 pm

Fred Peterson asks :
>> if the mean temperature is rising how much is attributable to man made CO2.
The further question is this : are the temperatures rising, or are the mean
temperatures rising … there is a difference … after all, you can increase the
mean temp. by extending the ‘warm’ season … this need not entail any actual
increase in temperatures
Further, if any increases in the mean are caused by rising temperatures,
are these increases in the minima, or increases in the maxima, or both.
After all, it is possible to have an increasing annual mean, coupled with
decreasing maximum temperatures.
I think that the concept of a “mean annual global temperature” is inutile.
Surely important climate changes are (1) seasonal, and (2) regional ?
( or perhaps my ‘surely’ is special pleading ! )
From a beautiful autumn day in Wellington, NZ

JFD
May 11, 2011 9:14 pm

Thanks, Anthony and your co-authors for tackling a big data handling job and making sense of the numbers so they could be used in a published paper. Thanks also, Anthony to you and your cast of hundreds of volunteers who visited and reviewed the measurement sites. You had a big job just to document the data in a usable manner.
Please take pride in what you do for climate science. You are one of the good’uns as are your volunteers.
I have one concern about using poor data when homogenization is used to adjust temperature readings up to 1200 km distance. As I understand it, this could result in using bad readings to adjust good readings and vice versa to a lesser degree. The whole homogenization effort leaves me cold.
I have used a bad thermometer to measure process temperatures many times, and then tested the same sites with a good thermometer when I could find a good one. The level of the readings of the bad thermometer is not correct but the differential temperature is usually close enough to draw conclusions about what the process is doing. Even given this, I would prefer an accurate temperature measurement – always.

Policyguy
May 11, 2011 9:35 pm

Anthony, earlier in this post someone commented on the rarity in climate “science” of people actually collecting and analyzing data so that some conclusions can be drawn about that data.
I’d like to echo that comment and join the choir of people that commend all of the volunteers and authors on this project, for gathering and interpreting this data for initial conclusions and so that it could be analyzed from a variety of perspectives.
Why aren’t others in this lucrative game doing this type of basic data based research that requires the collection and analysis of data?
I realize that this is a rhetorical question, but my hope is that legitimate inquiring minds that “know” of the scientific method (maybe they learned it in 8th grade?) will research the term, and apply it to today’s climate “science” to help slow down this conclusion dominated – model based (not data based)- prediction factory that is now being funded to prove a political/religious point.
High fives to all!!

May 11, 2011 9:53 pm

To the other “Mike” posting on this topic…
I am a meteorologist and one of Anthony’s surfacestation volunteer surveyors. I suspected that the warming trend would be overstated as a result of poor siting of so many of the stations. That has only partially turned out to be correct (for the mins), a result I didn’t expect.
BUT THAT IS HOW GOOD SCIENCE IS DONE. One does investigations and publishes the results regardless the personal expectations or beliefs of the person doing the research. You should be congratulating Anthony and company rather than making sarcastic postings. We have identified one more piece in the climate puzzle. Hooray.
Mike Smith

May 11, 2011 10:20 pm

Airports:
“” Most of the best-sited stations are at airports????
Twenty six years ago I first heard the term, “airport effect” as a cause of most of the measured warming.
So the study really didn’t address land use. This is a point that needs to be made.”
The case of airports versus non airports has been tested. Globally there is no difference.
We have looked at a case with only non airports. no difference.
I have seen a study done of japan which showed cooling at airports. One explanation is that airports tend to be constructed in areas with very low obstructions. airports tend to be constructed where there is a long fetch. Since UHI tends to infect Tmin rather than Tmax, one important thing to realize is that when windspeed gets above 7m/sec there is no UHI. Also, one major paper on UHI (parker) used a high percentage of airports and found no UHI signal.
So don’t expect a lot by controlling for the airport variable. This does not mean that you will find that every airport site is good. what it means is that globally the airport effect is small. IF it were large we would see clear differences between airport/non airport. we dont. If it were large we would see a big difference between all airport and UHA. we dont.
Again, do not expect all the warming we see (~1C over land) to vanish. It wont. It wont because its real. we know its real because of what UHA tells us, because SST has gone up since 1850 and because we can see other changes in proxies for temperature.

juanslayton
May 11, 2011 10:20 pm

LazyTeenager: So it’s time to do an experiment instead of relying on mistaken common sense. Build two weather stations side-by-side. One perfect and the other with asphalt and run both for a year. See then if the max and min trends cancel out.
Go for it! Too lazy to actually build stations? Not to worry, somebody else already has. Take a look at COOPs #244560 and #244558 (both at the Kalispell airport). Let us know what you come up with.

May 11, 2011 10:30 pm

Latitude.
So its the same temperature today as it was in the LIA?
or is it warmer now?
Is roy spencer lying about UHA?
http://www.woodfortrees.org/plot/uah/from:1979/to:2011/every/offset/plot/uah/from:1979/to:2011/trend/plot/hadcrut3vgl/from:1979/to:2011/trend/plot/none
What you see here is a warming planet. UHA is free of UHI. Its free of adjustments.
And look at the trend for CRU.
Question: if CRU has loads of UHI why isnt its trend different from CTU?
If CRU is adjusted to warm of cool planet why does it match?
Here another question. why does my temperature reconstruction that does not have any of CRU adjustments track CRU within .1C?
It’s warmer. The sea level rise tells us that. UHA tells us that. the glaciers tell that story. no story, no data, no theory, suggests that it cooler now than in the LIA.

Editor
May 12, 2011 12:29 am

Mosh
It was sometimes almost as warm at times in the LIA- depending on where you were- but generally it was cooler then than it is now, sometimes very markedly so.
Averages mask so many intersting variations when temperature records are really lots of peaks and troughs but I find it wholly unremarkable that the planet generally is warmer (thank goodness) now than it was then.
I put the low point as 1607 with a general-but not consistent-warming since then.
tonyb

Manfred
May 12, 2011 1:04 am

Another difference between UAH and land based measurements was identified by Frank Lasner a while ago. Sadly, it hadn’t been discussed when he posted it. I’ll try to do it here:
UAH land only and UAH sea surface only trends tend to converge to the same value from time to time. Land based land only and sea surface trends don’t.
The difference between land only and sea surface measurements has therefore been increasing all the time (excluding short term variations).
This is an unexpected behaviour. Of course, the land mass reacts quicker but as the land mass is strongly coupled with the oceans, a certain temperature difference would require a convergence of the trends.
In the simplest model
m(land) = k1*m(sea) – k2*(temp(land)-temp(sea))
where m is the linear trend slope
k1 accounts for the faster respones of the land mass
k2 accounts for the coupling of land mass and oceans.
A convergence of trends m(land) = m(sea) should then happen at a temperature difference of
temp(land)-temp(sea) = (k1-1)*m(sea) / k2.
As this hasn’t happened in ground based measurements. either k2, the coupling between oceans and land is extremely small and land response times to ocean temperatures are in the 100 years plus range or so. This is against all experience.
The other explanation would be a trend inflation affecting specifically the land only trend.

Keith Minto
May 12, 2011 1:12 am

It would be interesting to look at the nature of the instrument error. Temperatures recorded descending through max to min, I would say would be different from recordings made going from Tmin to Tmax. Is it assumed that the Tmax error is equal to the Tmin error ?
I am reminded of it in measuring blood pressure, if the sensor is not located properly, systolic always cuts off late, diastolic cuts in early resulting in an underestimate of the high end and an overestimate of the the lower reading. Not the same as temperature reading but an uncanny resemblance.

Roger Sowell says:
May 11, 2011 at 4:38 pm
It is a strange physics that allows a CO2 effect to be non-existent in some cities or other locations but not all such locations.

This comment goes to the heart of the ‘warming’ issue and should not be forgotten.

Patrik
May 12, 2011 1:39 am

steven mosher>> UAHCRU correlates well, yes.
None of them seem to correlate all that well with GISS:
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1990/plot/uah/offset:0.2/from:1990/plot/gistemp/from:1990
A (not very appropriate but anyway) extrapolation of those curves would probably yield quite different global means in 100 years.
My “analysis” here is 100% amateurish, I know, but have you made comparisons with GISS and if so, what have you concluded?

John Marshall
May 12, 2011 2:18 am

There are many errors in the data stream and all will have differing adjustments so how can we get any meaningful answer to the problem?
Far better to have sited these stations correctly in the first place.

Shevva
May 12, 2011 2:33 am

Sorry I would like to leave a political comment.
‘Power to the people’.
There the ‘People’ that spent ‘Their’ time and money on a project like this because they care about the world they live in and not because they get a grant or have some other motive.
To every single person involved in this please take my total gratitude.

Alexander K
May 12, 2011 2:42 am

Anthony, huge congratulations to the entire team for getting this massive job done and getting it through peer review to publication, all without government or institutional support. I have only skim-read the paper, but I take it that you and your team have low confidence in the veracity of the data overall due to the very small number of surface stations that comply with best practice and have a significant recording history over time; or did I get that wrong?

Shub Niggurath
May 12, 2011 4:19 am

Hi Anthony,
Do you think there is enough station classification data to put together a ‘best stations’ network for the US land mass?
Secondly, have you been approached by anyone wanting to do the same, from other countries? China and India would be good to study.

rpielke
May 12, 2011 5:05 am

Robert Morris – Thank you for correctly summarizing one of the implications of our study. As you write (with one edit]
“…the fact that the best and worst each have biases means rather than canceling them out they compound the uncertainty of any trend. In effect the margins of error are now expanded and the concept of a measured or understood trend in US temps is now demonstrably more [uncertain] than previously considered.”

Frank K.
May 12, 2011 5:33 am

Congratulations Anthony! And well done to all of the authors of the paper. Excellent work.

Volt Aire
May 12, 2011 5:52 am

Congrats and GJ all involved. I quess the basic outcome has been apparent from early statistical runs so kudos on pulling it through the process anyways. I can only assume a whole lot of climate science gets it’s plug pulled when the results do not obey the politics – so well done indeed.

Latitude
May 12, 2011 6:14 am

steven mosher says:
May 11, 2011 at 10:30 pm
Latitude.
So its the same temperature today as it was in the LIA?
or is it warmer now?
Is roy spencer lying about UHA?
=====================================================
Mosh, that’s not what I was talking about at all, and you know it.
But since you brought it up….
If you start those stupid temperature graphs at 1700 (LIA) like you mentioned, you get
the exact same slope we’re getting now. 1700-1800
That is natural global warming. Anything on top of that slope “could” be man made global warming.
But since both slopes are exactly the same, show me the man made signature.
The only way you can increase that slope is by adjusting past temperatures down, faking it, lying about past temperatures.

Warm
May 12, 2011 7:02 am

(sorry, I do not speak perfectly well english)
I noticed some weakness in the report of statistical results in the article.
– P values are not systematically reported. p=0.04 and p=0.00000001 are both significant at 0.05 level, but do not represent the same level of confidence..
– There is multiple comparaisons, what increase the risk of type I error. Examining 20 associations will produce one result that is “significant at P = 0.05” by
chance alone. This issue is not addressed.
– There is no assesment of effect size. Effect size allows the evaluation of the strength of an association, not only its statistical significance. Very small difference can be statistically significant, but without any practical importance…
References:
Sifting the evidence—what’s wrong with significance tests?
Jonathan A C Sterne, George Davey Smith
http://www.rni.helsinki.fi/~kja/epid10/article2.pdf
Effect size, confidence interval and statistical significance: a practical guide for biologists
Shinichi Nakagawa1,* and Innes C. Cuthill
http://www.kyb.mpg.de/bethge/teaching/introstats11/nakagawa2007.pdf

Edward
May 12, 2011 7:06 am

Martin says:
“Congratulations.
“even the best-sited stations may not be accurately measuring trends in temperature or, more generally, in trends in heat content of the air which includes the effect of water vapor trends. Also, most are at airports, are subject to encroaching urbanization,..” Most of the best-sited stations are at airports????
Twenty six years ago I first heard the term, “airport effect” as a cause of most of the measured warming.
So the study really didn’t address land use. This is a point that needs to be made.”
I think this is very important. So how does a site that was a field 50 years ago and now is a big city could now have underestimated (lower) max temps? My car thermometer says it is hotter in town than in rural areas during the hottest time of the day. Maybe land use changes have not been addressed. Maybe the many reasons for bad siting washes out any land use changes and maybe the statistical methods used also contribute to this washing out.

Richard M
May 12, 2011 7:37 am

I haven’t read the paper yet but a thought occurred to me that I haven’t seen mentioned.
The results may be reasonable from a purely scientific perspective. If heat is being captured during the day and released at night, then that heat is not present during the day to influence the high temperature for the day. Something to consider.
In addition, I have always assumed that weather stations for the most part are not in the heart of the cities. They exist mostly on the outskirts (airports). In my own situation I happen to live at the edge of a medium sized city. When I go into town I see typically see the temperature go up (especially in winter). However, when I go into the country I also see the temperature go down, usually much more than when I go into town.
Clearly, there is a UHI effect. However, the biggest part of the UHI effect is probably missing from our weather station data base. I realize this paper is trying to deal with microsite issues only, but growth in and around the microsite is probably just as big a factor if one is trying to understand the real warming.

Editor
May 12, 2011 8:23 am

Richard M
You might be intersted in these few article on UHI from my own web site.
http://climatereason.com/UHI/
Many weather stations move with surprising frequency and may become engulfed by urbanisation. Therefore a series of different micro climates ares often being recorded which may bear no relation to the one that the station started out in.
Many will argue that it is the anomaly that is important and provided these are consistent such aspects as you mention aren’t crucial.. Some of us disagree with that…
Tonyb

May 12, 2011 8:47 am

It looks like we are back to Satellite temperature records.

May 12, 2011 2:31 pm

@Latitude on May 11, 2011 at 6:16 pm
Re: So, what gives?
Regarding the 1989 article about global cooling, that is consistent with what I have seen in the temperature record for roughly 1890 to 1990. I wrote about this on my blog under the topic “Abilene Effect.” In short, there were some very cold and unusually frequent winters in the late 1970s and early 1980s. From the point of view in 1989, those five or six cold winters skewed the temperature trends downward, leading to the conclusion that the Earth was entering a global cooling period.
Enterprising climate scientists, though, have used that same cold period (1975 to 1985) to show a WARMING trend up through about 2000.
see http://sowellslawblog.blogspot.com/2010/02/abilene-effect-and-anomalies.html
There are so many holes in the CO2-causes-warming premise that it is no wonder that nothing goes right for those who predict catastrophe. As just one example, cold winters around 1980? But, CO2 causes WARMER winters – IPCC says so!
Sea levels rising due to thermal expansion and melting polar ice? Oops, Antarctic and Greenland ice masses are increasing, and the Pacific Ocean level is decreasing.
Snow is a thing of the past? Oops, there was snow just this past weekend at Lake Tahoe in California — with more snow on the way this weekend.
But, at least to me, the clincher is the fact that CO2 does not perform in a uniform manner, but appears to have no effect on come locations. How can so many sites in the US have zero warming, or even a cooling trend over roughly a 100 year time span, when neighboring cities have “global warming” due to CO2? Even using the climate scientists’s own data (HADCRUT3) and their anomalies to compare trends rather than absolute temperatures, one sees warming in some places but cooling in others. Physics does not allow arbitrary behavior – CO2 has to either heat everything up, or not heat any at all. This is especially true where the cities are all in the same hemisphere, all in the same general range of latitude, and all in the same general range of longitude. The lower 48 states in the USA all qualify for that last sentence.
As an example, Winnemucca, Nevada has a gently rising trend of 0.53 degrees C per century. Yet a neighboring city, Reno, has a trend almost 5 times greater at 2.55 degrees C per century. For another example, Abilene (Texas) shows a slight cooling trend of (minus) -0.19 degrees C per century, while its neighbor, El Paso, shows a slight warming trend of 0.71 degrees C per century.

shortie of greenbank
May 12, 2011 3:33 pm

Even if differences can be measured to say CRN 3,4,5 station measure warmer (higher than CRN 1,2 stations) at night and the opposite during the day it would be incomplete to argue long-term trends since site history seems to be lacking. It is only looking at the siting of now not the 30 or 115 year record (lawn and certain cropping areas return cooler but if for the reporting period the site has always had that then it should matter little in the long-term trends). Trends in sites where we know usage has not changed in the least is of most interest to me as was shown by Warwick Hughes in places like canefields just outside of Mackay, it has always been a canefield since the temperature has been recorded there and showed minimal warming (but was adjusted by almost 1oC due to being classed Urban and other places at airports being classed as Rural, go figure).
Well done to you Anthony and all the other volunteers involved in this exercise though, more representitive results are at least something that will come out of this.

May 12, 2011 5:06 pm

Richard M
“The results may be reasonable from a purely scientific perspective. If heat is being captured during the day and released at night, then that heat is not present during the day to influence the high temperature for the day. Something to consider.”
First lets be clear. There IS a UHI effect. We have many examples of this. In satillite imagery, in isolated site studies, and in transect studies.
Here is what these studies show.
1. the UHI effect is NOT spatially uniform. In fact some parts of a city or semi urban zone can be COOLER than the surrounding rural area. This is due primarily to canopy cover. See the study on portland or the studies on large european cities. What this means of course is that while the entire urban area as an averaged WHOLE is warmer, you will find what Oke called “cool parks”
2. The UHI effect depends upon the rural surroundings. See Oke
3. The UHI effect is not uniform in time. Very simply, some days are prone to more UHI than others. So a city may be warmer than the surrounding rural on one day, but the same temp on a different day. What drives this?
A. cloud cover
B. rain
C. season
D. wind.
So many readers here seeing a daily snapshot of UHI ( say 3C warmer) fail to realize that this is a low frequency occurence. let’s make an extreme example. If UHI happened one day of the year, a 10C warming would disappear in the yearly average.
If UHI only impacts Tmax at a site, then its impact is HALVED. why? because we look at Tave (Tmax+Tmin)/2.
So lets do a sample back of the envelop guesstimate just to show you the problem.
Tmax gets a 3C bias on sunny windless days.
Tave will show a 1.5C bias on sunny windless days.
if 10% of your days are sunny and windless then you can see how a big 3C effect gets diminished in a monthly and yearly average.
Finally, Not ONLY does the heat have to be released at night, BUT it has to be release at precisely the right time. what time? well when the thermometer records Tmin.
In many cases this is the early morning. NOW, if we integrated temperature every 5 minutes we would see the increase in nighttime temps as heat is released, but since we take only one value (the lowest value recorded) then all the UHI heat could be released BEFORE tmin is recorded. So, the nights are warmer for a while, but eventually they reach a tmin which is not effected by UHI. When you think about the whole problem, you quickly becme aware that UHI is not a simple thing to discover in the temp record.

Manfred
May 12, 2011 5:26 pm

As some commenters compare UAH with CRU, here is what would be expected:
There is no reason to believe, UAH and CRU trends should be same same. Similarly, everybody expects Arctic trends to be higher than global trends.
Over land, UAH trend should be 1.1 times higher and over oceans 1.6 times higher,, resulting in an overall trend increase by approx. a factor of 1.5.
As the UAH trend is actually lower than CRU, there is a HUGE discrepancy between these datasets.
http://blogs.agu.org/wildwildscience/files/2009/11/2009_Klotzbach_etal6.pdf
http://hurricane.atmos.colostate.edu/Includes/Documents/Publications/klotzbachetal2010.pdf

May 12, 2011 5:44 pm

Steve, it is very disturbing to see you use the word “deny” for aspects of climate science that are disputed. That is the type of tactic I would expect from an alarmist.
I don’t see the arguments you presented (1+2) as the norm. The LIA is only mentioned in the context of the MWP or when used to define the starting point of the instrumental record.
Most people who argue for the existence of the MWP do so based on extensive scientific evidence,
http://www.co2science.org/data/mwp/mwpp.php
The question of whether the MWP was warmer than today is very relevant to determine if there is any cause for alarm.
Regardless the debate becomes largely irrelevant once it is acknowledged that any current warming is “unremarkable”, which I believe it is. This is why the unprecedented argument is critical for proponents of mitigation policies.

Fred Peterson
May 12, 2011 6:55 pm

@Rex
Indeed. All good points / questions. Nice Autumn day in Perth 24C and blue sky in the middle of a huge record breaking drought in SW WA ,unlike the rest of Australia. So very aware of local variability / issues.
However the main game here is the carbon tax. I won’t go into how crazy this tax is (others are far more eloquent). The issue the taxers are saying is that temps are rising due to CO2 therefore we have to reduce the CO2 by taxing “polluters”. CO2 concentration is taken as a global number in popular discussion. So a global temp (probably the mean) is a simplistic number (I agree) to allow communication to the proletariate.
A small poll here in Perth found that
CO2 comprises less than 1/20th of one percent of the earth’s atmosphere – it is a trace gas. Just 7% of respondents knew that CO2’s concentration was under 1%; a sizeable 44% saying more than 10% concentration and 21% saying CO2 represents more than 50% of the atmosphere (Stephen L. Harper April 29th 2011 I think posted here and at Jo Nova’s site)
So imho we have to keep things simple (even if inaccurate to some degree) to communicate with a population with that level of understanding.
Which is why this Surface Stations work is so important (back on topic). We need to know and trust that at least the temperature numbers come from a sound base and are valid over a long time frame.

May 12, 2011 7:00 pm

@Poptech,
Another reason we know that the current temperature state (warmer) is not without precedent is the ancient hunter whose body was discovered in the Alps a few years ago, after a glacier had partially melted. It would appear that the ancient one had been mortally wounded by an arrow and died in the Alpine pass. Either he dug a hole down and into the glacier, fell into a crevasse in an existing glacier, or his body was later covered by snow that turned into a glacier. As he was not wearing cold-weather clothes, it would appear he was later covered by snow that turned into a glacier.
It’s a bit hard to believe that today is warmer than then, as the glacier has only now receded to the point that the body could be discovered.

Richard M
May 12, 2011 7:16 pm

steven mosher says:
May 12, 2011 at 5:06 pm
Richard M
“The results may be reasonable from a purely scientific perspective. If heat is being captured during the day and released at night, then that heat is not present during the day to influence the high temperature for the day. Something to consider.”
First lets be clear. There IS a UHI effect. We have many examples of this. In satillite imagery, in isolated site studies, and in transect studies. [snip]

Well Steve, that’s all very nice, but I was referring specifically here to the micro-site situation of lower daytime temps and higher nighttime temps of poorly sited stations. From there I went into a discussion of UHI, maybe I didn’t break the two apart clearly.
The thought I was trying to get through is possibly the microsite situation has a reasonable cause AND, IN ADDITION, ALSO was masking a more substantial UHI effect than we realize.

juanslayton
May 12, 2011 9:46 pm

Steve Mosher: See the study on portland….
I’d like to look at this. Any chance you have a link? Portland, Maine? Oregon?

John Finn
May 13, 2011 1:45 am

steven mosher says:
May 12, 2011 at 5:06 pm

In addition to your points there is also the fact that if there is no trend in the UH contribution then UH cannot affect the temperature trend at a given location.

May 13, 2011 4:38 am

Typos:
“… both an area of asphalt (which is warmer than the surroundings on a sunny day or irrigated lawns (which is cooler than surrounding bare soil on a sunny day)”
[Missing “)” after “day”]
“Menne at et al (2010).”
[and there should be a period after “al”]

Dean Morrison
May 13, 2011 4:57 am

I note the abstract of the paper ends with this statement:
“According to the best-sited stations, the diurnal temperature range in the lower 48 states has no century-scale trend.”
But climate scientists and the climate models never said it should did they? And the reason why? because both daytime and night-time temperatures are increasing. Why is that? Because of the blanketing effect of greenhouse gases, which warm the planet by trapping radiation both night and day. What you’ve drawn attention to is an observation which is a powerful piece of evidence that global warming is because of greenhouse gases, and not the sun, because any in any model where you increase solar forcing, daytime temperatures increase relative to night-time temperatures.
Well done Anthony for drawing attention to this important piece of evidence for AGW.

Dean Morrison
May 13, 2011 9:37 am

Richard S Courtney said:
“And, as is usual with the most interesting of studies, the findings are not what anybody could have predicted.”
Well they certainly don’t support the hypothesis that global warming is an artefact caused by poorly sited stations and the urban heat island effect.
Since others have looked at this data, and shown in peer reviewed papers that removing poorly sited stations makes absolutely no difference to the long term trend of global warming – I think the result of this paper is precisely what they predicted, and they’ve been vindicated.
There is now much moving of goalposts. The observation about no trend in diurnal temperature range based on the best quality stations is inconsequential and a distraction from the clear admission that the claim that global warming is an artefact from it’s main proponent. It is always possible to make ‘interesting’ observations if you trawl through enough, but you can’t say such observations vindicate your hypothesis unless you made a hypothesis beforehand. What we see here is a clear example of blasting a barn door with a shotgun. drawing a target around a cluster of pellet holes and claiming to be a sharpshooter. To say that ‘it matters quite a bit’ that diurnal temperature range is underestimated by poorly sited stations as Pielke Sr does is post hoc rationalisation for the exercise. If indeed ‘it matters quite a bit’ why did was the importance of this drawn to our attention before the exercise was undertaken. The obvious fact that the underestimate means that if anything, the true situation regarding global warming is worse than stated is something that neither Roger Pielke or Anthony Watts thinks ‘matters quite a bit’ otherwise why not draw attention to obvious conclusion.
As for it being ‘fortuitous’ that errors cancel out – that’s a remarkable way to justify a null result. There are errors in the measurement of any physical phenomenon, and the entire field of statistics has been developed in order to deal with them. Measurements always vary around a mean, typically in a Gaussian bell curve – and to blame this on fortuitous ‘luck’ if the result doesn’t please you is simply sour grapes.
However I am pleased to see that the authors of this paper are now taking an interest in the rest of the world. It wasn’t so long ago that claims were being made that there hadn’t been any increase in global temperature since the 1930’s, on the basis of a outlying data point from the 2% of the globe that is the USA. Good luck with extending the surface stations project to the rest of the globe though. I think you’ll find that McDonalds car parks and unfortunately sited air conditioning units are in short supply in the Antartic, Chile, the Australian Outback or Siberia, not to mention the 70% of the Earth’s surface that is covered in water.
Whilst I commend the citizen science exercise that Anthony set in motion, and the submission of a paper for peer-review, I also think the attempts to spin this into something positive for the ‘sceptics’ really are rather desperate.

May 13, 2011 9:50 am

Dean Morrison,
The current trend goes back to the LIA, well before the start of the industrial revolution. Further, temperatures declined for thirty years, between 1940 and 1970 – right in the middle of the industrial revolution. And the current very mild natural warming cycle is nothing new.
Even Phil Jones shows that the current trend is not unusual. Since the trend goes back to at least the beginning of the LIA, your conjecture that GHGs make a measurable difference fails, and the null hypothesis remains unfalsified.

Richard M
May 13, 2011 10:52 am

Dean Morrison, the paper discusses microsite problems, not UHI. These stations might also be impacted by UHI and the degree is still an open question. In fact, it’s possible the better microsites could exist in more significant UHI areas. Could be one reason for the results.
Might not be the best time to uncork that champagne.

May 13, 2011 7:38 pm

Anthony Watts, in the June 2010 you made a tour of Australia in which you gave an interview at the ABC which included this:
“Dr Pielke, his research group and myself are now in the process of finishing a paper for submission to a peer reviewed scientific journal that illustrates what we found in the way that siting difference has affected the US temperature record. And I can say with certainty that our findings show that there are differences in siting that cause a difference in temperatures, not only from a high and low type measurement but also from a trend measurement and a trend calculation…..
Michael Duffy: In which direction does the bias lie? Are you suggesting that the temperature has not got as hot as the American official historical record suggests?
Anthony Watts: That’s correct. It’s an interesting situation. The early arguments against this project said that all of these different biases are going to cancel themselves out and there would be cool biases as well as warm biases, but we discovered that that wasn’t the case. The vast majority of them are warm biases, and even such things as people thinking a tree might in fact keep the temperature cooler doesn’t really end up that way. ”
So, what changed?
You would probably know that your interview was extracted by Andrew Bolt, a very popular (and politically influential) “skeptic” blogger in Australia.
Do you have any concern about correcting the false impression you gave about the forthcoming results, even at a time you said the paper was close to its finalisation?
REPLY: Apparently you and the folks at Deltoid missed this, but that’s understandable when you want to play the denigration game that goes on there, or “rubbishing” as you call it. The fact is, you folks would “rubbish” the conclusions no matter what they were. Here’s a must read to help you understand should you choose to:
Something for Everyone: Fall et al. 2011 John Nielsen Gammon
As you may have heard, the long-awaited peer-reviewed analysis of the results of the SurfaceStations.org project has finally been released. I can’t wait to see the dueling headlines. Some will argue that the take-home message should be: Poor Station Siting Strongly Effects Temperature Trend Measurements, and will laugh at the idea that we can say with sufficient accuracy what has happened to our climate. Others will argue that the take-home message should be: Poor Station Siting Has No Effect on Temperature Trend Measurements, and will laugh at all the effort expended on a null result. Both sides will find solid evidence for their points of view in the paper. How can that be? How can one paper support opposing conclusions?
Read it all here: http://blog.chron.com/climateabyss/2011/05/something-for-everyone-fall-et-al-2011/
The simple and most indisputable fact about the USHCN surface network is clearly shown in this chart.
http://surfacestations.org/Figure1_USHCN_Pie.jpg
Only 1 in 10 meet climate station siting requirements by the NOAA adopted CRN rating, and the vast majority have a warm bias based on the Climate Reference Network rating system error magnitude numbers. There’s no mistaking that. At the time of that interview, and today, that statement remains true. Note the paper was submitted in October 2010, not June. Analysis by John N-G didn’t commence until we completed all the survey QC, and that took quite a bit of time.
In a couple of days, I’ll have my writeup and you can practice your “rubbishing” further on that. Be sure to heed Dr. Neilsen-Gammon’s writeup first though. – Anthony

Dean Morrison
May 14, 2011 7:44 am

Smokey – you say with confidence that the trend goes back to the ‘Little Ice Age’?
How do you know this? Do you have secret access to an unimpeachable temperature record stretching back centuries on which to base such a statement? Or perhaps you feel able to accurately reconstruct global temperatures with great precision on the basis of some Viking sagas about a failed colonisation of a few villages a few centuries ago?
I think us scientists will stick with the surface temperature record from thousands of sites around the world, which is confirmed not only by cutting edge satellite technology, but also by Anthony Watts. Feel free to stick with mythology if you prefer, but don’t expect to be taken seriously.

Dean Morrison
May 14, 2011 7:55 am

Richard M – you say that the paper concerns itself with ‘microsite problems, and not the UHI’. I’m afraid that quite simply you are wrong. The hypothesis put forward by Anthony Watts and others is that global warming is merely an artefact caused by a systematic problem of poorly sited stations falsely showing a global warming signal because of increasing urbanisation and the Urban Heat Island effect. Anthony’s paper shows no such signal, and confirms several other pieces of work which show that station quality is not responsible for the globally observed trend of warming. Furthermore, by pointing out that there is no increasing trend in diurnal variation, Anthony points to a powerful piece of evidence that such warming is because of greenhouse gases, and against the hypothesis that it is because of increased solar activity. We should be grateful to Anthony for exposing his work to peer review, but I’m afraid it confirms not only what is already known, but the predictions of climate models. If you have a hypothesis that something has been missed, or that something is Anthony’s work, then you are free to conduct your own research, and if you feel it supports you hypothesis, to submit you evidence for peer review. However your postulations alone do not count as evidence, and do nothing at all to counter the overwhelming established scientific evidence for global warming.

May 14, 2011 8:00 am

Dean Morrison,
You’re not really up to speed, are you? Here’s a chart of the gradually rising temperature trend since the LIA. The CET record is as ‘unimpeachable’ as any you will find anywhere.
As you can see, my statement was based on empirical evidence, not on Viking sagas, etc. But nice try at misdirection, and thanx for playing.☺

Dean Morrison
May 14, 2011 8:21 am

Smokey – the data you presented doesn’t include the Little Ice Age which you mentioned. The scales are arranged to deliberately downplay the increasing rate of warming since 1880. In the Central England Temperature record there is no statically significant warming from 1660 to 1890, and if anything there is a slight cooling trend. Since then there has been steadily increasing warming, with a plateau in the middle of the last century, followed by warming at an increasing rate. The same general picture is true of all of the data sets you show, and therefore the red lines that have been put through those charts are deliberately misleading. Globally the upward trend in temperature is detectable only from about 1880 – and not as you say from the ‘Little Ice Age’. If you want to provide evidence for your assertion you need to show there was significant global warming during the period 1660- 1880. That’s assuming of course you are going to use actual temperature measurements, rather than paintings of ice fairs… 😉

May 14, 2011 8:52 am

Dean Morrison,
First you claimed that my view was based on Viking saga and paintings of ice fairs, etc., while disregarding the links in my previous comment. Then when I posted charts of the clearly rising temperature trend line from the LIA, you bizarrely claimed that it shows a cooling trend. The obvious conclusion is that your mind is already made up, the science is settled, and all evidence that contradicts your world view is simply rejected. It is clear that none of the facts I could provide would make any difference to you.
That being the case, I won’t bother. Arguing against cognitive dissonance is fruitless. But now it’s my turn to ask you a question, since you claim to be one of “us scientists”: can you provide any empirical, testable evidence, per the scientific method, showing global damage due to CO2? No one else has been able to, but maybe you can.

May 14, 2011 9:12 am

Congratulations Anthony et al. Don’t I recall that the worst of the warming trends was supposed to be manifested in higher minimum (night-time) temperatures? It seems to me that the difference in trends between poorly-sited and well-sited surface stations in your study is telling. I’m looking forward to your further analysis of this report.

Editor
May 14, 2011 9:17 am

Dean Morrison
I am absolutely incredulous that you can make the assertions you did to Smokey (8.21 and previously)
This is my web site;
http://www.climatereason.com
In it I collect historic temperature records dating back to 1659. I have also written a number of articles on the increasing warmth from the low point of 1607.
There were ups and downs of course (a period from 1698 to 1730 was very similar to today) but basically there has been a slow and unremarkable warming captured in CET and other records.
I would respectfully suggest you read a few books by such as Hubert Lamb-the first Director of CRU. He was certainly aware of this long term warming and dated the retreat of the glaciers to around 1750. A good one is;
‘Climate, History and the Modern World’ ISBN 0415-12735-1
Here is a Blow by Blow account of the steady rise in warmth throughout the 19th century;
http://wattsupwiththat.com/2010/12/05/has-charles-dickens-shaped-our-perception-of-climate-change/
As it happens my next article is called ‘The long slow thaw’ and deals with this gradual warming from 1607. Fortunately we have a wealth of diaries, church records, crop records and instrumental records etc that show this centuries old rise very clearly and demonstrate that it didn’t start at 1880.
If you are American and would like to search the articles on my web site you will see two from me that noted the steady warming in the US in the 19th century and comments on the oddity of James Hansen commencing his records just as the temperature turned down temporarily, thereby missing out on the preceding warmth and accentuating the slope of the subsequent rise.
Incidentally, CET in 1659-the first year of CET- was exactly the same as 2010-the last year of the record at 8.83C
tonyb

Mike B
May 14, 2011 11:04 am

I am just an occasional viewer of your web site. I am a conservative person that believes there is a little warming going on, but probably being over stated by the alarmists. This surface station project has been very interesting. Many times, you pointed out the badly sited stations with the implication that they were overstating temperatures. I had come to the belief that a significant portion of the increase in temperatures could have been from poor measuring sites. Now based on your summary of this analysis it appears that the bad siting has very little effect on the mean temperatures. Does this mean that the alarmists are more correct than I thought? I’m afraid they will use this study to claim the skeptics have just lost one of their arguments in trying to refute man made global warming. I think this will be viewed as a big win for them and their cause, but the results are what they are and we should respect people like you that give us honest information. Thank you.
REPLY: It is one way of analyzing the data, but it doesn’t take into account everything that we learned along the way. Peer review makes one stop at a certain point and stick with what you have then. What we learned was that the problem was more complex than we first thought. Look for a second paper. Science builds on levels of understanding. – Anthony

Dean Morrison
May 14, 2011 11:12 am

Smokey – you wrote:
“First you claimed that my view was based on Viking saga and paintings of ice fairs, etc., while disregarding the links in my previous comment. Then when I posted charts of the clearly rising temperature trend line from the LIA, you bizarrely claimed that it shows a cooling trend. ”
Since the global temperature we are currently experiencing is unprecedented in thousands, and perhaps hundreds of thousands of years, they you could pick a starting point at any point in that time period and show a rising trend. The point is that there is a distinct warming phase which started around 1880, which was preceded by centuries of relative global stability. As for a ‘Little Ice Age’ – where is your temperature record to show this was a global rather than a regional phenomenon? There is no global instrumental record of course – so the only alternative is to use proxies such as bore holes, isotope ratios in ice bubbles, stalactites or others – all of which give ‘hockey stick’ shapes of course. I’m afraid that too many sceptics point to the Viking settlement of Greenland as ‘proof’ of both a medieval warm period and a Little Ice Age, without realising that is a very unreliable proxy indeed. Maybe you are not one of them, and discount such ‘evidence’ in which case I apologise.
On the other hand I note you say your graphic shows a steadily rising temperature change since the ‘end of the Little Ice Age’. Strangely it would seem from your graphic that the Little Ice Age ends at the precise moment when people start to measure temperature. Therefore according to you it ended in 1840 in Copenhagen; 1820 in Washington DC, New York and Minneapolis; 1760 in Geneva; 1740 in St Petersburg; 1730 in Berlin and 1660 in Central England. Funny that. How do you square a global ‘Little Ice Age” with such wide regional variation? Or perhaps you have discovered some hitherto unnoticed phenomenon, whereby temperature goes up as soon as anyone takes a thermometer to a new part of the globe?
Nice try, but I wouldn’t bother trying to get that past peer review if I was you… 😉

Dean Morrison
May 14, 2011 11:34 am

Hi Tony.
I’m impressed you have a website and have written articles where you express your opinion. Do you have anything you have submitted for peer review? The stuff about Dickens and Napoleon and so on is very entertaining, but I’m more interested in statistical analysis of data, rather than anecdotes and cherry picked records from single locations. Since Smokey can’t seem to make his mind up, and you seem to be something of a historian – perhaps you’d like to commit to a date for the end of the ‘Little Ice Age’? Incidentally much is made of the CET series – but I think you should show as much scepticism towards the early part of it as has been shown to the modern Surface Station record for the USA. For example – from Wiki:
“Data quality
Although best efforts have been made by Manley and subsequent researchers to quality control the series, there are data problems in the early years, with some non-instrumental data used. These problems account for the lower precision to which the early monthly means were quoted by Manley. Parker et al. (1992) [1] addressed this by not using data prior to 1772, since their daily series required more accurate data than did the original seies of monthly means; MBH98 only used data from 1730 onwards. Before 1722, instrumental records do not overlap and Manley used a non-instrumental series from Utrecht compiled by Labrijn (1945), to make the monthly central England temperature (CET) series complete. Between 1723 and the 1760s most observations were taken not from outside measurements but from indoor readings in unheated rooms, and thus are of little or no use.”
“Indoor readings in unheated rooms”?
Where would such a ‘station’ rank on Anthony’s scale of station quality do you think? Not to mention the fact that there is no possibilty of using a mean of stations so errors cancel each other out.
I’m sorry Tony, I’m really more interested in proper statistical analysis of data using scientific methods – I’ve browsed your website, but I don’t see where you’ve attempted to do this.
I also note that on your website you make the claim that the increase in temperature since 1880 is due to increased population. Now that is something I can agree with. However you then state with confidence that this is because of the influence of the Urban Heat Island Effect on surface stations. Now that Anthony has debunked such claims, will you be updating your website to correct this?

Editor
May 14, 2011 3:12 pm

Hi Dean
Bit confused anout which points you are making here.
I think the temperature record is extremely flawed and can be used as nothing more than an indication of direction of temperatures. Due to the many inconsistencies in the methods of measuring we can not get closer than a 1 degree temperature error and in many cases rather more than that. It is nonsense for anyone including Hansen to parse such poor records to tenths of a degree and produce this as scientific evidence of anything.
I have also written about temperature readngs being taken in unheated rooms etc so there is no need to quote Wiki to me. I have also written about the way in which CET has been consructed so again this is all well known
Quite how you subject such poor quality data to a proper statistical analysis is something you could perhaps enlighten me on? Once we get to the 1980’s and digital automatic weather stations I suppose we can start to get some accuracy for individual locations but then we run into (some) siting problems.
That some data is highly corrupted by uhi is something that is evident from observations, that some is problematic because the site has become urbanised or moved is also problematic. This is something that Phil jones has attempted to unravel with various grants from the EU.
Rather than read Wiki why don’t you try out some Lamb-its mostly very interesting and doesn’t rely as heavily on theoretical computer analysis of suspect data to arrive at results as do much of the work that appears in papers.
tonyb

Dean Morrison
May 14, 2011 5:31 pm

Tony – you said this:
“Due to the many inconsistencies in the methods of measuring we can not get closer than a 1 degree temperature error and in many cases rather more than that.”
Do you have any scientific evidence for your statement, or was that something you thought up yourself? Remembering of course that absolute temperature is unimportant when the matter in question is trend, then yes, it is entirely possible to make meaningful measurements of a fraction of a degree.
Could you please cite the scientific evidence on which you base your assertion?
You also made this extraordinary statement: “Quite how you subject such poor quality data to a proper statistical analysis is something you could perhaps enlighten me on?”
You seem to be unaware that the entire field of statistics was developed to deal with poor quality data, and to extract the underlying signals lying within it? Even the simple expedient of making repeated measurements and defining a mean will improve on raw data, and there are many more sophisticated methods which advance things further still. The very communications technology we are using at this moment depends on such methods, so you can hardly deny their effectiveness. Of course if you have one measurement made at one point in time in a situation where there is the likelihood of a systematic error, then statistics can’t help you – but then it was you that made a comparison between one such record from central England in 1659 and compared it to modern data.
Anthony’s paper is a comprehensive rebuttal of your claim that modern data is ‘corrupted by the UHI’ Tony. The fact that it merely replicates many previous such findings would make it unremarkable, if it were not for the fact that he has been the principle proponent of the hypothesis you are still clinging to.
Frankly I don’t see the relevance of the source of Phil Jones grant funding Tony. Perhaps you could explain why it matters here, and why you chose to mention it – perhaps I’m missing something?
It seems you don’t like works that “rely as heavily on theoretical computer analysis of suspect data to arrive at results as do much of the work that appears in papers.”
That’s a perfect description of what Anthony et al. have done in this peer reviewed work. Are you discounting it because it fits in that category.
Personally I’m sceptical of historical temperature reconstructions which seem to be based on an analysis of the the life and times of Charles Dickens. That’s perhaps because I’m sceptical by nature, and because I’m more interested in science than literature.

Richard M
May 14, 2011 8:24 pm

Dean Morrison is obviously in denial of basic facts. That puts him squarely in the TROLL category. Much of what he has posted so far is total nonsense. He either didn’t read the paper or ignores what is stated.

Editor
May 15, 2011 1:26 am

iDean
You said
“You seem to be unaware that the entire field of statistics was developed to deal with poor quality data, and to extract the underlying signals lying within it? Even the simple expedient of making repeated measurements and defining a mean will improve on raw data, and there are many more sophisticated methods which advance things further still.”
That is realy quite insulting. Of course if you take say 10 measurements of a single temperature point then there are ways of extracting a perfrectly meaningful result from it. However that wasn’t done was it? A SINGLE measurement was taken often at inconsistent times of day (or missed out altogether) using uncalibrated equipment and untrained observers and the night time temperature then either dreamt up or not used at all. We started to obtain some sort of consistency with the introduction of Stevenson screens and professional onservers but multiplying hundreds of highly dubiuous records a la Hansen to obtain a meaningful global average accurate to tenths of a degree back to 1880 is torturing the data to the nth degree.
Anomalies rely on accurate measurements as much as an actual reading if any sort of ‘scientific’ result is to be obtained.
We also have the complication that even today there are up to 30% of locations in the world cooling for a statistically meaningful period, so although the warming signal ( for whatever reason) overwhelms it the notion of a ‘global’ warming is untrue.
The relevance of Phil jones’ funding is that he was also unable to extract accurate information from the data. I am perfectly happy with computer analysis when it uses information that is accurate to begin with.
I think we are the only people left talking in an empty room as the party has moved elsewhere so hope to see you again on another thread.
All the best
tonyb

Dean Morrison
May 15, 2011 2:39 am

Dear Richard,
I’ll chose to ignore the gratuitous insult, and instead engage with what you’ve said.
Perhaps you could explain to me what you think are the pertinent facts that I’m in denial of?
Also, you say I haven’t read the paper – which I can in fact reassure you that I have. In fact you’ll see I quoted the concluding statement from the abstract in my first post here. However you say I have ‘ignored what is stated’. Perhaps you could quote to me the key passages you think I have ignored?
If you can do so I think we may be able to proceed on the basis of constructive dialogue, rather than the trading of insults.

May 15, 2011 5:39 am

Richard M says, regarding Dean Morrison:
“Much of what he has posted so far is total nonsense.”
Concur. His preposterous assertion that temperatures are higher today than for hundreds of thousands of years is flatly contradicted by the evidence from ice cores in both hemispheres.
Morrison previously asserted that there was a cooling trend since the LIA. But presented with a chart of the natural warming trend, he reversed his position. Classic cognitive dissonance. As Orwell describes it, “doublethink”: holding two contradictory thoughts at the same time. The classic alarmist mindset.
I would explain the null hypothesis to Dean, but I don’t want his head to explode.

May 15, 2011 5:45 am

Morrison is a conspiracy theorist who cannot provide evidence for his libelous claims.

Dean Morrison
May 15, 2011 7:57 am

Smokey – you seem to have picked two data series which suit your purposes and in doing so ignore the entirety of evidence not only from all the other available ice cores, but also evidence form the dozens of other proxies which all show unprecedented temperatures in recent times. I can’t say I recognise either of the data sets you cited – your the unreferenced figure you give for Vostok certainly doesn’t resemble anything published in a peer reviewed journal. What is your source for it? However that is of little import compared to the fact that you appear to have cherry picked to make your point. The temperature reconstructions published in the peer reviewed literature show that current global temperatures are unprecedented over a very long timescale. You might disagree with that, but it’s a fact. To prove me wrong you need to cite a global temperature reconstruction which is at odd with what I’ve said, not a couple of data points of your choosing.
I didn’t ‘assert there was a ‘cooling trend since the end of the Little Ice Age Smokey, for the rather obvious reason that I happen not to think that the ‘Little Ice Age’ was a global phenomenon. The peer-reviewed literature actually shows a slight downward trend going back one or two thousand years at least – until the latter part of the 1800’s. That trend is most marked in the reconstruction offered by McShane and Whyner, who actually hold a ‘sceptic’ position – so what I’m saying is unremarkable and shouldn’t really be controversial. If you are hostile to this evidence, I suggest you also take things up with those in your own camp who have interpreted the evidence this way and had success in getting their work published in a peer reviewed journal. The cognitive dissonance is all yours I think.
There really is no need to explain the null hypothesis to me Smokey, or to make derogatory remarks. If you feel you are in the position where the evidence supports your position, there should be no need for you to lower yourself to such a level to win the argument.

Dean Morrison
May 15, 2011 8:24 am

Tony,
You were the one who put great store on the individual records from early in the CET data, not me. However since you said:
“Of course if you take say 10 measurements of a single temperature point then there are ways of extracting a perfrectly meaningful result from it.”
– and of course if you take hundreds or thousands on a daily basis from many disperate locations you can get an even meaningful result from it. The quality of the data can give meaningful results with a much greater accuracy than ‘a degree’ and therefore you are conceding that the following statement you made was incorrect:
“Due to the many inconsistencies in the methods of measuring we can not get closer than a 1 degree temperature error and in many cases rather more than that. It is nonsense for anyone including Hansen to parse such poor records to tenths of a degree and produce this as scientific evidence of anything.”
I asked you why you mentioned that Jones had funding from Europe, and why you thought this was relevant. You don’t seem to have been able to answer. The European Union funds a lot of scientific research – is your point that they shouldn’t? Or does the fact the funding comes from the European Union somehow ‘taint’ the research? Or perhaps you meant something else? Could you explain please.
And yes – you’re right – the argument has effectively moved on. Now that Anthony and the others have admitted in a peer reviewed paper that the quality of US surface stations and urbanisation is not responsible for the upward trend in the global temperature record, we are able to move on to more important matters. I’m sure there will be some die-hards who will question Anthony’s research, and either try to pick holes in it or say that the US isn’t representative of the globe after all, but they really are flogging a dead horse. Apart from anything the satellite record confirmed the surface data long ago – and that includes the satellite data from UAH produced by the sceptics Christie and Spencer:
http://en.wikipedia.org/wiki/UAH_satellite_temperature_dataset
Not only do mainstream scientists think that the rise in global temperature is real, they have now been joined by Spencer, Christie and now Watts; who have replicated the work in peer-reviewed literature. The BEST analysis has been accepted by all sides as an agreed means of settling the matter – and of course the provisional results from that confirm the long-held mainstream position.
So, as you said, the argument is over, and science moves on.

May 15, 2011 8:54 am

Dean Morrison,
It is a fact that you cannot provide evidence for your false assertion that current temperatures are higher than during the last hundreds of thousands of years:
click1 [Greenland/Antarctica overlay showing a global effect]
click2
click3
click4 [from Law Dome, yet another ice core site]
click5
I have lots more charts all showing evidence that past temperatures exceeded current temperatures. Most use data that has been peer reviewed. Just ask, and I’ll post them for you. I doubt if you will ask, though, since they explicitly contradict your false belief that the current temperature is… the hottest evah!
You may now return to Skeptical Pseudo-Science and RealClimatePropaganda for more debunked talking points.☺

Dean Morrison
May 15, 2011 9:21 am

Dear Smokey,
those figures are pretty meaningless unless they are sourced to peer-reviewed work. Some of them show no sources of any kind. It is not sufficient for you to say they’ve used ‘data that has been peer reviewed’ – that is possibly the case but that does not mean that any subsequent treatment therefore also becomes ‘peer-reviewed’.
Could you reference the scientific papers they come from please, or am I to assume that they’ve been lifted from blogs of some kind?
In the meantime here is some recent peer-reviewed work:
Evidence that North Atlantic temperatures are unprecedented in at least the last 200 years:
http://www.sciencemag.org/content/331/6016/450.abstract
Evidence that temperatures in the Northern Hemisphere in the last two decades are unprecedented in the last millennium:
http://onlinelibrary.wiley.com/doi/10.1111/j.1468-0459.2011.00002.x/abstract
Evidence that temperatures in Lake Tanganika are unprecedented since at least AD 500
http://www.nature.com/ngeo/journal/v3/n6/abs/ngeo865.html
– and here’s one that’s very relevant to Anthony’s paper. There is good reason to believe that early methods of recording temperature has a systematic bias towards warmth – and therefore if anything the degree of global warming may have been underestimated because of the surface station record. If the Surface Stations project wishes to extend its remit to the rest of the world, then I hope that in the interests of impartiality they are are as interested in potential bias such as that described here, as any bias which may fit the narrative that global warming is exaggerated…
http://www.springerlink.com/content/g111046235jnv572/

Gneiss
May 15, 2011 9:25 am

Smokey writes,
“I have lots more charts all showing evidence that past temperatures exceeded current temperatures. Most use data that has been peer reviewed. ”
None of the five charts you linked come within a century of “current temperatures,” do they? So they essentially show past temperatures in Greenland or Antarctica exceeded those at the close of the Little Ice Age.

May 15, 2011 9:43 am

Gneiss,
It’s easy to show how wrong you are. Just look at the temperatures on the charts. The current very *mild* 0.7°C rise over the past century and a half doesn’t come close to past temperature rises.
The Minoan Optimum, the Holocene Optimum, the Roman Optimum and the Medieval Warm Period all exceeded today’s temperatures by between one and 3 degrees [and the previous interglacial was even warmer]. They are called “optimum” because warmer is better – cold kills. Only in the lunatic world of CAGW climate “science” do we find the preposterous scare stories about [evidence-free] runaway global warming.
# # #
Dean Morrison says:
“Could you reference the scientific papers they come from please, or am I to assume that they’ve been lifted from blogs of some kind?”
Obviously you’re thrashing around trying to find something to criticize. The data sources are right in most of the charts. Take a look.

Gneiss
May 15, 2011 9:56 am

Smokey writes,
“Obviously you’re thrashing around trying to find something to criticize. The data sources are right in most of the charts. Take a look. ”
Smokey, if you actually looked up the original papers by scientists, you could learn that (for example) the Greenland temperature reconstruction based on GISP2 which you’ve so often cited ends in the year 1855. The Little Ice Age.

Dean Morrison
May 15, 2011 1:28 pm

I take it you couldn’t find any peer-reviewed work by scientists which supports your position Smokey, otherwise you’d have cited it.
I’m sorry – given the choice between the published and peer-reviewed work of the overwhelming majority of the world’s scientists – reinforced now by this paper by Watts et al; and what appears to be your layman’s opinion based on your reading of partial and cherry-picked data – I’m afraid I have to go with the scientists. I’ve just been to visit a friend of mine this evening who is at death’s door in intensive care. He’s hooked up to every machine conceivable, and is receiving the close attention of consultants who have spent a lifetime dedicated to study of sick people and using the latest available scientific information to effect a cure. I’d rather put my faith in their expertise, and the track record of evidence based medicine, rather than listen to a hospital porter who says the entire medical profession is engaged in a grand conspiracy based on convincing people that patients like my friend are ill, when actually they are fine and dandy.
Perhaps you can see why I approach your claims with a similar degree of scepticism?

Dean Morrison
May 15, 2011 1:47 pm

Poptech.
Still no response as to who I’m supposed to have libelled here…
You do realise that comments on this blog are moderated, and therefore Anthony takes responsibility for what is published here? If your suggestion is that I’ve libelled Anthony for some reason, I’m afraid you are quite simply wrong, because not only did Anthony allow my comments to pass moderation, but if he’d considered them libellous, he’d effectively have been responsible for publishing a libel against himself. Try getting that one through the law courts – even in the UK. If you think I’m responsible for libelling some other person, then I’m afraid then that Anthony would also be held responsible for publishing my comments. Since I don’t recall mentioning anyone else, except perhaps Pielke Sr, then I think that unlikely. As for the people involved in our discussion, since it would seem to be only myself and Richard Courtney who choose to post under their whole real name, rather than a pseudonym, I don’t think anyone here is in a position to say they’ve been libelled.
Of course the decent thing for you to do would be to withdraw the accusation if you don’t intend to back it up. However since you chose to make it whilst hiding behind a pseudonym, I can’t say I really expect that to happen. However this is the first time I’ve posted on this blog and I have to say I am a little disappointed in the approach of some of the commentators here, which doesn’t seem to be entirely serious, or in the spirit of a genuine interest in the science. Are such attitudes commonplace here, or have I pressed the wrong buttons or something?

Gneiss
May 15, 2011 1:51 pm

Richard M writes,
“Dean Morrison is obviously in denial of basic facts. That puts him squarely in the TROLL category. Much of what he has posted so far is total nonsense. He either didn’t read the paper or ignores what is stated.”
That’s a lot of name-calling, Richard. And yet Dean is the one who has shown a knowledge of science here, and who has cited recent peer-reviewed studies in support of his points. Which of these are “total nonsense” or “in denial of basic facts,” Richard?
“Evidence that North Atlantic temperatures are unprecedented in at least the last 200 years:”
http://www.sciencemag.org/content/331/6016/450.abstract
“Evidence that temperatures in the Northern Hemisphere in the last two decades are unprecedented in the last millennium:”
http://onlinelibrary.wiley.com/doi/10.1111/j.1468-0459.2011.00002.x/abstract
“Evidence that temperatures in Lake Tanganika are unprecedented since at least AD 500”
http://www.nature.com/ngeo/journal/v3/n6/abs/ngeo865.html
“- and here’s one that’s very relevant to Anthony’s paper. There is good reason to believe that early methods of recording temperature has a systematic bias towards warmth – and therefore if anything the degree of global warming may have been underestimated….”
http://www.springerlink.com/content/g111046235jnv572/

May 15, 2011 2:30 pm

Gneiss says:
“Smokey, if you actually looked up the original papers by scientists, you could learn that (for example) the Greenland temperature reconstruction based on GISP2 which you’ve so often cited ends in the year 1855. The Little Ice Age.”
Old news, and if you ever put on your thinking cap on, you might finally understand that since your 1850’s reference point, the global temperature has risen only about 0.7°C. That still leaves current temperatures well below the MWP, the Holocene Optimim, the Roman Optimum and the Minoan Optimum.
Why is that so hard for you to understand? Current temperatures have been routinely exceeded in the recent geologic past. And CAGW has been debunked by the ultimate authority: the planet itself. If you don’t like what the planet is telling us, go on the internet and complain.
# # #
Dean Morrison says:
“I take it you couldn’t find any peer-reviewed work by scientists which supports your position Smokey, otherwise you’d have cited it.”
That statement is just non-factual hogwash like all your other alarmist gibberish.
The pointers to the peer reviewed papers are right in the charts, as I’ve patiently explained to you above. I’m not being paid to spoon-feed you what you can easily find with a simple search. eg: “R.B. Alley, climate”. There you go, junior. Have at it.
Now run along back to skeptical pseudoscience for the latest super-easy-to-debunk talking points.

May 15, 2011 3:14 pm

Dean, Anthony is in no way responsible for your comments, made from your computer via your IP address. Having moderation turned on does not make him anymore responsible for what you choose to post.
You have libeled the reputable scientists in the other thread with false accusations you cannot back up,
http://wattsupwiththat.com/2011/05/14/smear-job-by-the-carbon-brief/#comment-660565
Yeah sure you are all “disappointed” for posting libelous statements about reputable scientists and then getting called on it.

Gneiss
May 15, 2011 3:20 pm

Smokey writes,
“Old news, and if you ever put on your thinking cap on, you might finally understand that since your 1850′s reference point, the global temperature has risen only about 0.7°C.”
So you believe that the temperature at Summit, Greenland has risen only 0.7°C, like HadCRU’s global index, since 1855? And that the central Greenland temperature anomaly in 985 represented the whole globe?

May 15, 2011 3:27 pm

Gneiss,
Your first link concerns only the Arctic region around Svaalbard. That’s not global, is it?
Your next link uses tree ring proxies – a notoriously unreliable temperature proxy, as Mann and Briffa showed, to their public embarrassment. You want to show that tree rings corellate with temperature? No problem. You want to show that tree rings corellate with CO2? No problem. Take your cherry-pick.
There is no long term temperature proxy that comes close to the accuracy of ice cores, and the ice core evidence tells a completely different story.
Your next link? You really need to get up to speed, that was the paper that Willis Eschenbach debunked in Nature.
Your final link is once again a report on the Greater Alpine Region [GAR]. We’re debating catastrophic anthropogenic global warming. Stick to the issue, instead of trying to move the goal posts by cherry-picking regions that seem to support your beliefs. The climate is different in different regions, and the climate is always changing somewhere. That’s why they’re called climate regions. See?

May 15, 2011 3:52 pm

Gneiss,
Once again with the climate regions?
And there is corroborrating evidence from both hemispheres showing global temperature change.
Happy to be of service teaching you things you apparently didn’t know.☺

Gneiss
May 15, 2011 4:00 pm

Smokey writes,
“Your first link concerns only the Arctic region around Svaalbard. That’s not global, is it?”
Let’s take just that first link, an article by Spielhagen et al. (2011), and go a step farther than sound bites. Here, with emphasis added, is the paper’s concluding paragraph:
“Although we cannot quantify from our data the variability of previous inflow to the Arctic by volume, our temperature data series and the above observational link suggest that the modern warm AW [Atlantic water] inflow (averaged over two to three decades) is anomalous and unique in the past 2000 years and not just the latest in a series of natural multidecadal oscillations. Both effects—a temperature rise as well as a volume transport increase—introduce a larger heat input into the Arctic Ocean. Although there is no direct contact of the AAWL [Arctic Atlantic water layer] with the ocean surface in the Arctic, such an increased heat input has far-reaching consequences.
The strong AW warming event in the Arctic Ocean in the 1990s caused a shoaling of the AW core and an enhanced heat flux to the surface (29), concurrent with decreasing sea ice (4). Recent oceanographic data from the Laptev Sea continental margin indicate the impact of warm AW-related water masses on the shallow (80-year time series. The data also provide evidence for a significant heat flux to the overlying shelf waters (30). Even without any modification of the vertical heat transfer processes, the enhanced temperature contrast between the AW and the surface sea water freezing point (increased from ~5 to 7 K as identified here) leads to an increase in the vertical heat flux of ~40%. Any positive feedback mechanism will magnify the effect of this flux increase on the ice cover. Complementing the strong feedback between ice and atmospheric temperatures (1), warming of the AW layer, unprecedented in the past 2000 years, is most likely another key element in the transition toward a future ice-free Arctic Ocean.

May 15, 2011 8:59 pm

OK, back on topic.
Anthony, over the weekend I found your radio interview with Andrew Bolt in Australia from June 2010 in which you said you estimated that warming bias from siting factors could account for .5 degree C of warming. Andrew then made the observation that this meant that 2/3 of the roughly .7 degree warming of the last century could be due to this alone, and I don’t believe you disagreed.
Is your coming post going to make reference to that specific estimate of only 13 months ago in light of your paper?

June 13, 2011 12:11 pm

I suggest a phrasing change:
“The minimum temperature rise appears to have been overestimated, but the maximum temperature rise appears to have been underestimated.”
would be better written:
“The rise in minimum temperatures appears to have been overestimated, but the rise in maximum temperatures appears to have been underestimated.”
…so that it is clear what the adjectives “minimum” and “maximum” are intended to modify.
Dave