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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The Roman Climate Optimum represents one of the warmer periods in earths history. Can someone explain this since this period was way before cars, etc.

Member Since: April 26, 2009 Posts: 3 Comments: 3667
827. HadesGodWyvern (Mod)
Tropical Cyclone Warning Center Darwin
Tropical Cyclone Advice #23
TROPICAL LOW, FORMER OLGA (07U)
5:00 AM CST January 27 2010
========================================

At 3:30 am CST, Tropical Low, Former Olga (997 hPa) located at 16.1S 137.4E or located 115 kms east of Borroloola and 200 kms west northwest of Mornington Island has 10 minute sustained winds of 25 knots with gusts of 45 knots. The low is reported as moving northwest at 9 knots.

Dvorak Intensity: T2.0/2.0/D1.0/24HRS

Ex-Tropical Cyclone Olga is currently located near the coast and is expected to move northwest, remaining close to the coast. Ex-Tropical Cyclone Olga is expected to redevelop over water near the coast late today. Redevelopment may occur sooner if Ex-Tropical Cyclone Olga takes a more northward track into the Gulf of Carpentaria.

GALES with gusts to 110 kilometres per hour are expected to develop between the NT/Qld Border and Cape Shield, including Groote Eylandt, later today or early Thursday. GALES with gusts to 110 kilometres per hour may develop as far east as Burketown in Queensland, including Mornington Island, during today if Ex-Tropical Cyclone Olga takes a more northward track.

HEAVY RAIN may lead to significant stream rises in the Roper-McArthur District

Tropical Cyclone Warnings
===================================
A Cyclone WARNING is now current for coastal and island communities from Cape Shield, including Groote Eylandt in the Northern Territory to Burketown in Queensland.

Forecast and Intensity
=====================
12 HRS: 15.5S 136.3E - 30 knots (Tropical Low)
24 HRS: 14.9S 135.8E - 40 knots (CAT 1)
48 HRS: 15.0S 136.8E - 60 knots (CAT 2)
72 HRS: 16.4S 140.3E - 80 knots (CAT 3)

Additional Information
=========================
Ex-TC Olga was located by radar and surface observations close to the SE Gulf of Carpentaria coast. Convective bands have developed around the LLCC. Dvorak DT unclear, with FT based on MET and PAT, MET/PAT=2.0. The system is forecast to continue move NW under the influence of the mid-level steering ridge to the south and remain close to the southern Gulf of Carpentaria coast, before recurving towards the N or NE late Wednesday or Thursday as an upper trough amplifies over central Australia. The broad-scale environment is very favourable for redevelopment of a tropical cyclone when the LLCC moves further over southern Gulf of Carpentaria waters, with divergent outflow aloft and strong monsoonal westerlies to the north.
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Quoting JFLORIDA:
WunderBlogs - Dr. Masters' Blog Content Rules

No hot linking external or copyright images without the image owner's permission.

No comments that contain only personal notes such as, "Good Morning!", or "You've got mail, X".


Fair use would stipulate a REFERENCE or LINK at LEAST.


Mail
Member Since: June 28, 2006 Posts: 25 Comments: 8325
MYTH: Global temperatures are rising at a rapid, unprecedented rate.

FACT: Accurate satellite, balloon and mountain top observations made over the last three decades have not shown any significant change in the long term rate of increase in global temperatures. Average ground station readings do show a mild warming of 0.6 to 0.8C over the last 100 years, which is well within the natural variations recorded in the last millennium. The ground station network suffers from an uneven distribution across the globe; the stations are preferentially located in growing urban and industrial areas ("heat islands"), which show substantially higher readings than adjacent rural areas ("land use effects").

Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting JFLORIDA:


Ive seen Ham shacks with sophisticated weather instrumentation. Id assume radio stations and other entities would have similar instrumentation.

DR M ID the example he used thus:

A poorly sited temperature sensor in Marysville, California, used for the USHCN.

Any of the stations that show on the WU as MADIS stations are used (with some QC) for modeling. And most are part of the GHCN.
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Quoting McBill:

What you're showing are pictures of housings, not temperature sensors. How do you know what's inside?

BTW - if you want people to take you seriously on the issue, spamming the blog isn't going to help. FWIW


Im not taking you seriously. Your not making any sense.

Member Since: August 11, 2008 Posts: 0 Comments: 2315
Quoting McBill:

What you're showing are pictures of housings, not temperature sensors. How do you know what's inside?

BTW - if you want people to take you seriously on the issue, spamming the blog isn't going to help. FWIW


How do I know what's inside? LOL!!!

You can ask the exact same question about the one posted by Dr. Masters!
Member Since: June 28, 2006 Posts: 25 Comments: 8325
Quoting CatchMeifUCan:
temperature station is located in Eastport, Maine and is especially mind-boggling. This is a state of the art meteorological station that has the thermometer two feet downwind from the air conditioner condenser. Thanks to Anthony Watts, the arrows in the picture show how the little fan inside the thermometer housing draws air into the sensor.




Anthony Watts should be applauded for all of his work in this arena!
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting PcolaDan:


mail


LOL replied
Member Since: June 28, 2006 Posts: 25 Comments: 8325
Quoting JFLORIDA:


good question and one that deserves an answer. Unfortunately as they are not used for measurement and modeling I dont see the reliance.

Oh, yes they are. (At least the MMS pics from t-dude).

So is this one:



Here is the sign attached to the fence:


sarc: I wonder if anything has changed in the last 143 years... [/sarc]

Tough to pick out when the parking lot was paved...or the increasing vehicular traffic over the years. One would need to compare to a pristine, rural site nearby to make any use of this...

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Quoting tornadodude:


mail
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting McBill:

Sorry, but where's your evidence that any of those are used by the NCDC? They just look like random pictures to me.


Those type of sensors are used by the NCDC. You dont find those kind of thermometers for personnel use.
Member Since: August 11, 2008 Posts: 0 Comments: 2315
Severe Weather reports from iReport (CNN), from last 48h.

Is Woodstock the Next Niagara?
Flooding in Dolgeville,New
Small stream flooding
storms destruction
Peru Macchu Picchu floods
Heavy rains, winds, and warm
Heavy rains and warm weather
http://www.ireport.com/ir-topic-stories.jspa?topicId=1303
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Quoting McBill:

Sorry, but where's your evidence that any of those are used by the NCDC? They just look like random pictures to me.


I didnt say they were. I just said I was posting examples of the thermometers mentioned in the blog entry.
Member Since: June 28, 2006 Posts: 25 Comments: 8325
Now
Scattered light snow showers will move across northern Maryland...the eastern West Virginia panhandle...and extreme northern virgina through the afternoon. Brief moderate bursts of snow may reduce visibility to under 2 miles...mainly close to the Pennsylvania border. West winds of 10 to 15 mph will occasionally gust to 25 mph. With temperatures in the upper 30s...no accumulation is expected.
Lo: 26
Mostly cloudy this evening...then becoming partly cloudy. Lows in the upper 20s. West winds 10 to 15 mph.

Friday
1/29/2010
Hi: 31
Cloudy with a 30 percent chance of snow. Highs in the upper 20s.
Lo: 24
Snow likely. Lows around 20. Chance of snow 60 percent.

Saturday
1/30/2010
Hi: 30
Snow likely. Highs in the mid 20s. Chance of snow 60 percent.
Lo: 16
Snow likely. Lows 15 to 20. Chance of snow 60 percent.

from Weatherbug
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Member Since: June 28, 2006 Posts: 25 Comments: 8325
Quoting CaneWarning:
Can someone explain why there was a huge surge in CO2 levels after WWII, but global temperatures fell?


Testing of atomic BOMBS, they put a lot into the atmosphere, im pretty sure there was a volcano eruption to during WW2.
Member Since: August 11, 2008 Posts: 0 Comments: 2315
Quoting TampaTom:
Everyone in Florida...

Tomorrow is the Statewide Tornado Drill. We've been Tweeting about it.

We are planning a drill at our office... And the school system is doing their annual drill tomorrow to coincide.

Anyone else doing anything?


No plans here in my office building.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Here is a list of the scheduled talks...Should be a great event:

This year, FSU faculty and staff from the Meteorology and Oceanography Depts. will be giving weather talks geared toward the general public on popular topics of the day. Scheduled topics are listed below.


"El Niño and its Impact on the Southeast U.S." by NWS Tallahassee Meteorologist-in-Charge, Paul Duval

"Shocking Facts about Lightning" by Dr. Henry Fuelberg

"Meteorology on the Gulf" by Dr. Paul Ruscher

"Climate Change and ClimateGate" by Dr. Jon Ahlquist

"Slowing Down of the Global Conveyor Belt and It's Impact on the Climate" by Physical Oceanography graduate student, Mona Behl
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Can someone explain why there was a huge surge in CO2 levels after WWII, but global temperatures fell?
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting McBill:
re 780, 781, 786 & 793:

tornadodude, what do you see as the significance of the pictures you posted? Especially in light of the paper from Menne et al discussed in Dr. Masters' blog entry.


This pictures being shown, depict how inaccurate weather sensors can be when to close to concrete materials and other things that put off heat.
Member Since: August 11, 2008 Posts: 0 Comments: 2315
Everyone in Florida...

Tomorrow is the Statewide Tornado Drill. We've been Tweeting about it.

We are planning a drill at our office... And the school system is doing their annual drill tomorrow to coincide.

Anyone else doing anything?
Member Since: Posts: Comments:
Quoting McBill:
re 780, 781 & 786:

tornadodude, what do you see as the significance of the pictures you posted? Especially in light of the paper from Menne et al discussed in Dr. Masters' blog entry.


oh, I was just showing examples of the thermometers he was referencing
Member Since: June 28, 2006 Posts: 25 Comments: 8325
Member Since: June 28, 2006 Posts: 25 Comments: 8325
Good Afternoon. For those of you from/in North Florida, the NWS Office in Tallahassee (located on the campus of Florida State) is having it's 2nd annual WeatherFest this coming Saturday from 10:00 to 5:00. Good weatherfun/information for the Family and a chance to chat up the Mets. Here is a sample from the event menu. Hope to see some WU folks there. I'll be the "older" man with the young children in tow walking around in a brown cap (hiding the bald spot) like in my Avatar....Rock & Roll keeps me young........ :)

After a very successful event in 2009, WeatherFest will be returning on
January 30, 2010.

WeatherFest is an outreach event developed by the National Weather Service office in Tallahassee and organized in partnership with the Florida State University Meteorology Department, the North Florida Chapter of the American Meteorology Society, and state and university emergency management officials. This annual event is intended for weather enthusiasts of all ages and brings together meteorology professionals from the federal and state government, academia, the media, and various partner organizations, to increase awareness about how forecasts and warnings are produced and disseminated, how meteorologists are trained, and the science of meteorology in general.

WeatherFest 2010 will be part of Florida's Severe Weather Awareness Week, and will feature many of the events from the inaugural WeatherFest last January, with some new and exciting exhibits in store as well. Food and drinks will be available for purchase. If you didn't visit us last year, or missed the severe weather simulation or weather balloon launches, stop by and visit us this year! If you are curious about our 2009 event, check out the photo gallary provided by our photographer, Bob Duggan. We hope that you will plan to make WeatherFest 2010 part of your winter plans.

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World's glaciers continue to melt at historic rates

Latest figures show the world's glaciers are continuing to melt so fast that many will disappear by the middle of this century

Glaciers across the globe are continuing to melt so fast that many will disappear by the middle of this century, the World Glacier Monitoring Service (WGMS) said today.

The announcement of the latest annual results from monitoring in nine mountain ranges on four continents comes as doubts have been cast on how much climate scientists have exaggerated the problem of glacier melt, which is seen as a leading indicator of how much the planet is heating up.

Last week the head of the Intergovernmental Panel on Climate Change (IPCC) apologised for "a paragraph" in its four-volume 2007 report which warned there was a "very high" risk that the Himalayan glaciers, on which at least half a billion of the world's poorest people depend for water, would disappear by 2035.

However the director of the WGMS, Professor Wilfried Haeberli, said the latest global results indicated most glaciers were continuing to melt at historically high rates.

"The melting goes on," said Haeberli. "It's less extreme than in years [immediately before] but what's really important is the trend of 10 years or so, and that shows an unbroken acceleration in melting."
http://www.guardian.co.uk/environment/2010/jan/25/world-glacier-monitoring-service-figures
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Quoting CaneWarning:
tornadodude - too funny.


;)
Member Since: June 28, 2006 Posts: 25 Comments: 8325
tornadodude - too funny.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Member Since: June 28, 2006 Posts: 25 Comments: 8325
Quoting McBill:
re #769:

Somebody did a poor job of Photoshopping in those NOAA signs.


They did, It's a pathetic photoshop image. Ah well that sensor is still way to close to the road.
Member Since: August 11, 2008 Posts: 0 Comments: 2315
Quoting tornadodude:


George Bush has his right next to an ice cellar xD.
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.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Member Since: June 28, 2006 Posts: 25 Comments: 8325
Member Since: June 28, 2006 Posts: 25 Comments: 8325

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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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