Poorly sited U.S. temperature instruments not responsible for artificial warming

By: Dr. Jeff Masters , 5:57 PM GMT on January 25, 2010

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Former TV weatherman Anthony Watts, who runs the popular global warming contrarian website, "Watts Up With That", was convinced that many of the U.S. network of surface weather stations had serious flaws in their siting that was causing an artificial warm bias in the observed increase in U.S. temperatures of 1.1°F over the past century. To address this concern, Watts established the website surfacestations.org in 2007, which enlisted an army of volunteers to travel the U.S. to obtain photographic evidence of poor siting of weather stations. The goal was to document cases where "microclimate" influence was important, and could be contaminating temperature measurements. (Note that this is a separate issue from the Urban Heat Island, the phenomenon where a metropolitan area in general is warmer than surrounding rural areas). Watts' volunteers--650 strong--documented the siting of 865 of the 1,218 stations used in the National Climatic Data Center's U.S. Historical Climatology Network (USHCN) for tracking climate change. As reported in Watt's 2009 publication put out by the Heartland Institute, the volunteers "found stations located next to the exhaust fans of air conditioning units, surrounded by asphalt parking lots and roads, on blistering-hot rooftops, and near sidewalks and buildings that absorb and radiate heat." Watts surmised that these poorly-sited stations were responsible for much of the increase in U.S. temperatures over the past century, due to "a bias trend that likely results from the thermometers being closer to buildings, asphalt, etc." Watts concluded, "the U.S. temperature record is unreliable. And since the U.S. record is thought to be the best in the world, it follows that the global database is likely similarly compromised and unreliable".


Figure 1. A poorly sited temperature sensor in Marysville, California, used for the USHCN. The sensor is situation right next to an asphalt parking lot, instead in the middle of a grassy field, as it is supposed to be. The sensor is also adjacent to several several air conditioners that blow their exhaust into the air nearby. Image credit: surfacestation.org.

Analysis of the data disagrees with Watts' conclusion
While Watts' publication by the Heartland Institute is a valuable source of information on siting problems of the U.S. network of weather stations, the publication did not undergo peer-review--the process whereby three anonymous scientists who are experts in the field review a manuscript submitted for publication, and offer criticisms on the scientific validity of the results, resulting in revisions to the original paper or outright rejection. The Heartland Institute is an advocacy organization that accepts money from corporate benefactors such as the tobacco industry and fossil fuel industry, and publishes non-peer reviewed science that inevitably supports the interests of the groups paying for the studies. Watts did not actually analyze the data to see if taking out the poorly sited surface stations would have a significant impact on the observed 1.1°F increase in U.S. temperatures over the past century. His study would never have been publishable in a peer-reviewed scientific journal.


Figure 2. Annual average maximum and minimum unadjusted temperature change calculated using (c) maximum and (d) minimum temperatures from good and poor exposure sites (Menne 2010). Poor sites showed a cooler maximum temperature compared to good sites. For minimum temperature, the poor sites were slightly warmer. The net effect was a cool bias in poorly sited stations. The dashed lines are for stations ranked by NOAA, while the solid lines are for the stations ranked by surfacestations.org.

Fortunately, a proper analysis of the impact of these poorly-sited surface stations on the U.S. historical temperature record has now been done by Dr. Matthew Menne and co-authors at NOAA's National Climatic Data Center (NCDC). In a talk at last week's 90th Annual Meeting of the American Meteorological Society, Dr. Menne reported the results of their new paper just accepted for publication in the Journal of Geophysical Research titled, On the reliability of the U.S. Surface Temperature Record. Dr. Menne's study split the U.S. surface stations into two categories: good (rating 1 or 2) and bad (ratings 3, 4 or 5). They performed the analysis using both the rating provided by surfacestations.org, and from an independent rating provided by NOAA personnel. In general, the NOAA-provided ratings coincided with the ratings given by surfacestations.org. Of the NOAA-rated stations, only 71 stations fell into the "good" siting category, while 454 fell into the "bad" category. According to the authors, though, "the sites with good exposure, though small in number, are reasonably well distributed across the country and, as shown by Vose and Menne [2004], are of sufficient density to obtain a robust estimate of the CONUS average". Dr. Menne's study computed the average daily minimum and maximum temperatures from the good sites and poor sites. The results were surprising. While the poor sites had a slightly warmer average minimum temperature than the good sites (by 0.03°C), the average maximum temperature measured at the poor sites was significantly cooler (by 0.14°C) than the good sites. As a result, overall average temperatures measured at the poor sites were cooler than the good sites. This is the opposite of the conclusion reached by Anthony Watts in his 2009 Heartland Institute publication.

Why did the poorly sited stations measure cooler temperatures?
The reason why the poorly-sites stations measured cooler temperatures lies in the predominant types of thermometers used at the two types of sites. An electronic Maximum/Minimum Temperature System (MMTS) is used at 75% of the poor sites. These MMTS sensors are attached by cable to an indoor readout device, and are consequently limited by cable length as to how far they can be sited from the building housing the indoor readout device. As a result, they are often located close to heated buildings, paved surfaces, air conditioner exhausts, etc. It turns out that these MMTS thermometers have a flaw that causes them to measure minimum temperatures that are slightly too warm, and maximum temperatures that are considerably too cool, leading to an overall cool bias in measured average temperatures. In contrast, only 30% of the "good" sites used the MMTS sensors. The "good" sites predominantly used Liquid in Glass (LiG) thermometers housed in wooden shelters that were more easily located further from the buildings where the observers worked. Since the poorly-sites stations were dominantly equipped with MMTS thermometers, they tended to measure temperatures that were too cool, despite their poor siting.


Figure 3. Comparison of U.S. average annual (a) maximum and (b) minimum temperatures calculated using USHCN version 2 temperatures. Temperatures were adjusted to correct for changes in instrumentation, station relocations, and changes in the time of observation, making the trend from good sites show close agreement with poor sites. Good and poor site ratings are based on surfacestations.org. For comparison, the data between 2004 - 2008 taken by the new high-quality U.S. Climate Reference Network (USCRN, black dashed line) is shown, and displays excellent agreement for that time period. Image credit: Menne 2010.

Independent verification of recent USHCN annual temperatures
Clearly, the siting of many of the surface stations used to track climate change in the U.S. is not good. To address this issue, in 2004 NOAA created the U.S. Climate Reference Network, a collection of 114 stations in the continental United States for the express purpose of detecting the national signal of climate change. The stations were sited and instrumented with climate studies in mind, and can provide an extremely high-quality independent check on the old USHCN network. Each of 114 stations at 107 locations (some stations were installed as nearby pairs) is equipped with very accurate instruments in a triplicate configuration so that each measurement can be checked for internal consistency. As shown in Figure 3, the USCRN air temperature departures for 2004 - 2008 are extremely well aligned with those derived from the USHCN version 2 temperature data. For these five years, the the difference between the mean annual temperatures measured by the old USHCN compared to the new USCRN was just 0.03°C, with a mathematical correlation coefficient (r-squared) of 0.997. Menne et al. concluded, "This finding provides independent verification that the USHCN version 2 data are consistent with research-quality measurements taken at pristine locations and do not contain spurious trends during the recent past even if sampled exclusively at poorly sited stations. While admittedly this period of coincident observations between the networks is rather brief, the value of the USCRN as a benchmark for reducing the uncertainty of historic observations from the USHCN and other networks will only increase with time". The authors finally concluded, "we find no evidence that the CONUS temperature trends are inflated due to poor siting".

Crediting Anthony Watts
The surfacestations.org effort coordinated by Anthony Watts has made a valuable contribution to science, helping us better understand the nature of the errors in the U.S. historical temperature data set. In his talk last week at the AMS conference, and in the credits of his paper, Dr. Menne had some genuinely grateful comments on the efforts of Anthony Watts and the volunteers of surfacestations.org. However, as of this writing, Watts has made no mention on surfacestations.org or on wattsupwiththat.com of Dr. Menne's study.

I'll have a new post Wednesday or Thursday.

Jeff Masters

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Just a note regarding Al Gore's electric bill...

What the Gore bashers conveniently neglect to mention is that 100% of the electricity the Gores purchase is generated from renewable sources - wind, solar, etc. In addition, those high bills oft quoted include power used during the construction process that converted the mansion to an efficient, LEED certified building.
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looks like activiity is on increase since jan 17 edvidence of even more activity on the horizon to the left in the image yet to rotate into view also note dark area in southern hem of sun and also to left nw of equatorial area sw of north pole looks like we may be in turn for a little increase activity in the near term anyway needs to be watched to see outcome
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ok bye..
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The post from the Doc tells us we do have issues with what is going on.

Is this video wrong? I sincerely want to know..






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Fascinating..,but Im still learning myself as well.

I learned this from the above entry today,..

Analysis of the data disagrees with Watts' conclusion
While Watts' publication by the Heartland Institute is a valuable source of information on siting problems of the U.S. network of weather stations, the publication did not undergo peer-review--the process whereby three anonymous scientists who are experts in the field review a manuscript submitted for publication, and offer criticisms on the scientific validity of the results, resulting in revisions to the original paper or outright rejection. The Heartland Institute is an advocacy organization that accepts money from corporate benefactors such as the tobacco industry and fossil fuel industry, and publishes non-peer reviewed science that inevitably supports the interests of the groups paying for the studies. Watts did not actually analyze the data to see if taking out the poorly sited surface stations would have a significant impact on the observed 1.1F increase in U.S. temperatures over the past century. His study would never have been publishable in a peer-reviewed scientific journal.
Member Since: July 3, 2005 Posts: 420 Comments: 127543
School kids verify NASA satellite observations


The S'COOL program has been urging students outside to help verify NASA satellite measurements and learn about clouds and climate for 13 years now. Credit: Science Directorate, NASA Langley Research Center

Most scientific observations are made by the most sophisticated of instruments. We build miles-long particle accelerators to see the smallest bits of atoms. We send bus-sized satellites all the way out to space to observe the dynamic interactions happening in our planet's atmosphere.

Sometimes, though, a machine just wont do. Sometimes a school kid looking up at the sky does the job quite well.

That is the premise of NASA's COOL (Students Cloud Observations On-Line) project. While a satellite passes overhead observing the radiation emitted by Earth, SCOOL participants look upwards and take careful notes on the type and multitude of clouds in the sky.

This is not just for fun, and it's not just to get children and teens interested in the basics of atmospheric science. These observations are put to use by NASA scientists to verify that a satellite instrument overhead the Clouds and the Earth's Radiant Energy System (CERES) sensor is accurately observing clouds from above. In some cases, CERES radiometers may interpret a glare or a land feature as a cloud. Student observations act as a ground truthing method to make sure the satellite is accurate.

The more observations, the better. In this regard, the gold star goes to the students at Chartiers-Houston Jr./Sr. High School in Houston, Pa. These students have made more than 5,000 all-time observations for the SCOOL folks at NASA's Langley Research Center. (5,276 observations as of Jan.10, to be exact.) The number is a record and nearly the doubles the total reported by any other school.

The SCOOL program is beginning its 14th year and has inspired school children in more than 75 countries to take their cloud charts outside. Chartiers-Houston has long been among the most active in the program. Students can make observations anytime, but ideally they walk outside at the precise time that the satellite is passing over their town. They must know the types of clouds and know the recording methods to make useful observations. This requires, in other words, dedication.

Science teacher Gary Popiolkowski, who's been leading students outside to look skyward since Aug. 2000, said he likes SCOOL because it allows students to get involved doing real science, acting like real scientists. He said his students even make observations after school and on weekends, on their own time.

My students have developed a sense of pride in continuing our observations over the years, he said. Besides recording the scheduled observations, we also identify the clouds each period throughout the day as a daily class starter. SCOOL is integrated into our weather unit and fits into my philosophy of no child left inside as we constantly look up anytime we are outside.

-- Patrick Lynch, NASA's Earth Science News Team
Member Since: July 3, 2005 Posts: 420 Comments: 127543
Quoting AstroHurricane001:
Since Pine Island Bay is past its tipping point, here is a youtube video showing the area: Link

I woner why he was not mention http://en.wikipedia.org/wiki/Moulin_%28geology%29
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Quoting AussieStorm:
Happy Australia Day everyone.


HBA
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Happy Australia Day everyone.
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Quoting gregpinehurstnc:
all . i wanted to know,, was the weather,, this is getting absurd, the weather in the next week,is all i would like to know,, if i could change climate and the weather,, my name would not be gregg,, it would be


Did you say you once worked for EA?
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Since Pine Island Bay is past its tipping point, here is a youtube video showing the area: Link
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Quoting gregpinehurstnc:
all . i wanted to know,, was the weather,, this is getting absurd, the weather in the next week,is all i would like to know,, if i could change climate and the weather,, my name would not be gregg,, it would be


type your zip code into the convenient search box located at the top of the page, click search, and there is the weather for the next week
Member Since: June 28, 2006 Posts: 24 Comments: 8201
all . i wanted to know,, was the weather,, this is getting absurd, the weather in the next week,is all i would like to know,, if i could change climate and the weather,, my name would not be gregg,, it would be
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Quoting Grothar:


I wish I could send you more, but I have to save the money for the electric bills. We expect to have a very hot summer here.

By the way, what personalized one?


Lol nice!

there is one with a note taped around it that reads "From your friend, Grothar Von Hapsburg"
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Quoting tornadodude:


Hey lol actually I have only drank 2 of them so far. I want them to last :P I am saving the personalized one, keeping another for after I graduate, and I promised a friend he could have one.


I wish I could send you more, but I have to save the money for the electric bills. We expect to have a very hot summer here.

By the way, what personalized one?
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Scan your elect bill block your name and post it
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Quoting Grothar:


PAT! LOL.


LOL :)
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Quoting Patrap:


Whats a Deusch,a small German?






PAT! LOL.
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Quoting Jeff9641:


And I thought Al Gore was all about the green movement with his $33,000 a month electric bill. What a deusch!


I'm not necessarily a fan of Al Gore's, but fair is fair. The rumor was $30,000 per year not $33,000 per month. Actually, my electric bill is more than the Gore's, (in the real figures), and I have more conservation measure in place than most. He is a link if anyone is interested in the truth.


Link
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Not peer reviewed? If all the "peers" think the same way you do, and any "peers" that think differently are suppressed, how is this whole warming thing anything other than junk science at its best?
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Quoting Jeff9641:


And I thought Al Gore was all about the green movement with his $33,000 a month electric bill. What a deusch!


Whats a Deusch,a small German?








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Quoting Grothar:


Hey, TD, any Urge left?


Hey lol actually I have only drank 2 of them so far. I want them to last :P I am saving the personalized one, keeping another for after I graduate, and I promised a friend he could have one.
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Quoting tornadodude:


LOL you were about $300 shy ;)

have a good one!


Hey, TD, any Urge left?
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Quoting spathy:
by 1990, NOAA had deleted from its datasets all but 1,500 of the 6,000 thermometers in service around the globe.

3 Times the same link? Maybe make it all bold ;)
Btw. no matter which dataset you take all are very close in agreement. So i guess all got it wrong and it's just a worldwide conspiracy behind it.
Back to work ;)
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Quoting tornadodude:


I wasnt showing that to dis him, I was comparing the electric bills of him and canewarning


Nor was I dissing him I did vote for the guy and like him sometimes....

Taco :0)
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Quoting CaneWarning:


LOL, I don't think my electric bill is as high as Al Gore's. Well folks, I'm going to save a bit of electricity and turn my computer off while I go watch some tv with my partner.


LOL you were about $300 shy ;)

have a good one!
Member Since: June 28, 2006 Posts: 24 Comments: 8201
Quoting tornadodude:


I wasnt showing that to dis him, I was comparing the electric bills of him and canewarning


LOL, I don't think my electric bill is as high as Al Gore's. Well folks, I'm going to save a bit of electricity and turn my computer off while I go watch some tv with my partner.
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Quoting GeoffreyWPB:


Agree Matt...it's getting old and tiring. Time to come up with something new.


I wasnt showing that to dis him, I was comparing the electric bills of him and canewarning
Member Since: June 28, 2006 Posts: 24 Comments: 8201
7. I run my pump all the time, year round.

canewarning, i'm thinking that's the one that is socking ya!
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Quoting tornadodude:
Que the dont hate on al gore cries :P


Agree Matt...it's getting old and tiring. Time to come up with something new.
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Quoting tornadodude:


right, it's an apartment?


Rental condos I believe
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Quoting CaneWarning:
It's not a house.


right, it's an apartment?
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It's not a house.
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Que the dont hate on al gore cries :P
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Quoting tornadodude:
is this your house?



Nope that Al Gore's House....
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Quoting CaneWarning:


LOL, no but I know where that is.


LOL figured you did since it's on your island :P
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Quoting tornadodude:
is this your house?



LOL, no but I know where that is.
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Quoting CaneWarning:


Wealth management


And I thought you were the Poster Child for the Power Company in S FL....

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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