Watts et al paper 2nd discussion thread

The first press release announcement thread is getting big and unwieldy, and some commenters can’t finish loading the thread, so I’m providing this one with some updates.

1. Thanks to everyone who has provided widespread review of our draft paper. There have been hundreds of suggestions and corrections, and for that I am very grateful.  That’s exactly what we hoped for, and can only make the paper better.

Edits are being made based on many of those suggestions. I’ll post up a revised draft in the next day.

2. Some valid criticisms have been made related to the issue of the TOBS data. This is a preliminary set of data, with corrections added for the “Time of Observation” which can in some cases result in double max-min readings being counted if not corrected for. It makes up a significant portion of adjustments prior to homogenization adjustments as seen below in this older USHCN1 graphic. TOBS is the black dotted line.

TOBS is a controversial adjustment. Proponents of the TOBS adjustment (Created by NCDC director Tom Karl) say that it is a necessary adjustment that fixes a known problem, others suggest that it is an overkill adjustment, that solves small problems but creates an even larger one. For example, from a recent post on Lucia’s by Zeke Hausfather, you can see how much adjustments go into the final product.

The question is: are these valid adjustments? Zeke seems to think so, but others do not.  Personally I think TOBS is a sledgehammer used to pound in a tack. This looks like a good time to settle the question once and for all.

Steve McIntyre is working through the TOBS entanglement with the station siting issue, saying “There is a confounding interaction with TOBS that needs to be allowed for…”, which is what Judith Curry might describe as a “wicked problem”. Steve has an older post on it here which can be a primer for learning about it.

The TOBS issue is one that may or may not make a difference in the final outcome of the Watts et al 2012 draft paper and it’s conclusions, but we asked for input, and that was one of the issues that stood out as a valid concern. We have to work through it to find out for sure. Dr. John Christy dealt with TOBS issues in his paper covered on WUWT: Christy on irrigation and regional temperature effects

Irrigation most likely to blame for Central California warming

A two-year study of San Joaquin Valley nights found that summer nighttime low temperatures in six counties of California’s Central Valley climbed about 5.5 degrees Fahrenheit (approximately 3.0 C) between 1910 and 2003. The study’s results will be published in the “Journal of Climate.”

Most interestingly, John Christy tells me that he had quite a time with having to “de-bias” data for his study, requiring looking at original observer reports and hand keying in data.

We have some other ideas. And of course new ideas on the TOBS issue are welcome too.

In other news, Dr. John Christy will be presenting at the Senate EPW hearing tomorrow, for which we hope to provide a live feed. Word is that Dr. Richard Muller will not be presenting.

Again, my thanks to everyone for all the ideas, help, and support!

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

UPDATE: elevated from a comment I made on the thread – Anthony

Why I don’t think much of TOBS adjustments

Nick Stoke’s explanation follows the official explanation, but from my travels to COOP stations, I met a lot of volunteers who mentioned that with the advent of MMTS, which has a memory, they tended not to worry much about the reading time as being at the station at a specific time every day was often inconvenient.. With the advent of the successor display to the MMTS unit, the LCD display based Nimbus, which has memory for up to 35 days (see spec sheet here http://www.srh.noaa.gov/srh/dad/coop/nimbus-spec.pdf) they stopped worrying about daily readings and simply filled them in at the end of the month by stepping through the display.

From the manual http://www.srh.noaa.gov/srh/dad/coop/nimbusmanual.pdf

Daily maximum and minimum temperatures:

· Memory switch and [Max/Min Recall] button give daily

highs and lows and their times

The Nimbus thermometer remembers the highs and lows for

the last 35 days and also records the times they occurred. This

information is retrieved sequentially day by day. The reading

of the 35 daily max/min values and the times of occurrence (as

opposed to the “global” max/min) are initiated by moving the

[Memory] switch to the left [On].

So, people being people, rather than being tied to the device, they tend to do it at their leisure if given the opportunity. One fellow told me (who had a Winneabago parked in is driveway) when I asked if he traveled much, he said he “travels a lot more now”. He had both the CRS and MMTS/Nimbus in his back yard. He said he traveled more now thanks to the memory on the Nimbus unit. I asked what he did before that, when all he had was the CRS and he said that “I’d get the temperatures out of the newspaper for each day”.

Granted, not all COOP volunteers were like this, and some were pretty tight lipped. Many were dedicated to the job. But human nature being what it is, what would you rather do? Stay at home and wait for temperature readings or take the car/Winnebago and visit the grand-kids? Who needs the MMTS ball and chain now that it has a memory?

I also noticed many observers now with consumer grade weather stations, with indoor readouts. A few of them put the weather station sensors on the CRS or very near it. Why go out in the rain/cold/snow to read the mercury thermometer when the memory of the weather station can do it for you.

My point is that actual times of observation may very well be all over the map. There’s no incentive for the COOP observer to do it at exactly the same time every day when they can just as easily do it however they want. They aren’t paid, and often don’t get any support from the local NWS office for months or years at a time. One woman begged me to talk to the local NWS office to see about getting a new thermometer mount for her max/min thermometer, since it wouldn’t lock into position properly and often would screw up the daily readings when it spun loose and reset the little iron pegs in the capillary tube.

Some local NWS personnel I talked to called the MMTS the “Mickey Mouse Temperature System” obviously a term of derision. Wonder why?

So my point in all this is that NWS/NOAA/NCDC is getting exactly what they paid for. And my view of the network is that it is filled with such randomness.

Nick Stokes and people like him who preach to us from on high, never leaving their government office to actually get out and talk to people doing the measurements, seem to think the algorithms devised and implemented from behind a desk overcome human urges to sleep in, visit the grand-kids, go out to dinner and get the reading later, or take a trip.

Reality is far different. I didn’t record these things on my survey forms when I did many of the surveys in 2007/2008/2009 because I didn’t want to embarrass observers. We already had NOAA going behind me and closing stations that were obscenely sited that appeared on WUWT, and the NCDC had already shut down the MMS database once citing “privacy concerns” which I ripped them a new one on when I pointed out they published pictures of observers at their homes standing in front of their stations, with their names on it. For example: http://www.nws.noaa.gov/om/coop/newsletters/07may-coop.pdf

So I think the USHCN network is a mess, and TOBS adjustments are a big hammer that misses the mark based on human behavior for filling out forms and times they can’t predict. There’s no “enforcer” that will show up from NOAA/NWS if you fudge the form. None of these people at NCDC get out in the field, but prefer to create algorithms from behind the desk. My view is that you can’t model reality if you don’t experience it, and they have no hands on experience nor clue in my view.

More to come…

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I have some additional thoughts up here: http://rankexploits.com/musings/2012/initial-thoughts-on-the-watts-et-al-draft/
Its intended as constructive criticism to help improve the paper, not an attack on Anthony or anything of that sort, so be civil.
[snip – Zeke we already covered this issue in email – Anthony]

Climatists’ have been, “locked into a simple-minded identification of climate with greenhouse-gas level. … That climate should be the function of a single parameter (like CO2) has always seemed implausible. Yet an obsessive focus on such an obvious oversimplification has likely set back progress by decades,” (Richard Lindzen, July 2012)
Facts are facts: the surface temperatures of the Earth constantly fluctuate. A supposed rise of temperatures of 0.8 °C in 150 years is just too small to worry about. This study analyzes the surface record as reported by the NOAA and shows half of the global warming in the USA is artificial. In addition to recording temperatures at poorly-sited stations located at airports and in urbanized areas that will of course show increases in temperature trends, Well sited rural, non-airport stations show a warming nearly three times greater after NOAA adjustment is applied.

For folks interested in the details of the adjustments NCDC does, this presentation by Menne at the 2011 AMS conference is a good accessible introduction: https://ams.confex.com/ams/19Applied/flvgateway.cgi/id/18288?recordingid=18288

Steve Huntwork

TOBS has always been a dating issue and never a temperature offset.
Think of a Sin wave being sampled by two observers 1/3 out of phase. Both will correctly record a +1.0 maximum and a -1.0 minimum over their periods of data recording.
To “adjust” one set of valid observations with a set temperature offset, would be dumb beyond belief.
Except for very rare occasions, the maximum temperature will occur around 2:00 PM local time and the minimum around local sunrise.
For after midnight recordings, both of the maximum and minimum temperatures will be dated for the previous day.
For post-sunrise recordings, the maximum temperature occurred on the previous day and the minimum was recorded on the CURRENT day.
This has always been a timing phase offset and never an error with the actual recorded data. Those minimum and maximum temperatures actually occurred.

Christoph Dollis

Thanks for this post and explanation of differing viewpoints on TOBS adjustments.
If I hadn’t made the point clearly in the other thread, I’ll reiterate it in paired down form here: I appreciate and respect both our host, Anthony Watts, and Steve McIntyre precisely for their airing out differences publicly and honestly. This is how it should be done, in my opinion.
McIntyre didn’t say definitively that he will sign on as a co-author in the final version to be presented for publication. I hope he does after properly weighing in on the paper.
REPLY: Steve contributed greatly to the first effort, creating a whole section, not naming him would have been a travesty. It will be his choice for the final though. – Anthony

Anthony, when will the list of station ids used in this paper and their classifications be made available? And maybe some detail about how the classification was made?
REPLY: Hello Ron,
We want to at least get the paper into submission form first, so that we can preserve the years of work that Evan and I and the many volunteers put into it by being able to submit first. Bear in mind that gathering this data caused out of pocket expenses and much time away from my family, plus my openness has been abused in the past. Both Menne et al and Muller/BEST submitted papers before we even got ours out the door. I don’t think it is unreasonable to get my submission in first for once.
That said, I’m intending to provide it to allow for full replication as I did to Dr. Muller and when Fall et al 2011 was published.
We do have description on how the classifications were done in the PowerPoints as well as the paper. – Anthony

William Roberts

Hey look at that, all suggestions for robust trend analysis are completely ignored!
REPLY: No that’s an assumption on your part. We’ve looked at everything in the thread, including yours. Suggestion: you’ll get further in this thread by being more cordial. People who also use their real name rather than lie with the first comment made by using a fake name, also tend to be taken more seriously. Thanks for your consideration. – Anthony

Jim Steele

TOBS adjustments always confused me. If a thermometer measures the maximum and minimum, why would TOBS affect a multidecadal trend? I had the impression the TOBS could alter a monthly or annual average because the depending on the Time of Observation the temperature could carry over into the next time period. But why would that affect a trend?

Christoph Dollis

“TOBS has always been a dating issue and never a temperature offset.
“Think of a Sin wave being sampled by two observers 1/3 out of phase. Both will correctly record a +1.0 maximum and a -1.0 minimum over their periods of data recording.”

Ummm, the difference is the temperature doesn’t fall and rise with the regularity of a Sine wave.

Geo

Thanks for all the work. You are correct, the pre-posting of this has been a remarkable success, and will assist in carving the way in how science can be reviewed by ALL!! I have one question….do you feel at all “bothered” by “tiresome” distracting questions from those who “only want to find fault with your work..”? ;P
REPLY: No of course not, if I was I’d be ignoring suggestions like the fact that TOBS needs to be addressed. So we are. I don’t mind valid criticisms of the work. Small minded people who want to tear me down personally or speak in third person lagomorphic languages do become tiresome though. – Anthony

Christoph Dollis

“You are correct, the pre-posting of this has been a remarkable success ….”

I think he jumped the gun by a week myself.

Steve Huntwork

“Ummm, the difference is the temperature doesn’t fall and rise with the regularity of a Sine wave.”
The phase of the sampling periods is what I was trying to express…
A difference in sample timing phases will never be a linear offset.
A very simple concept if you think about it…

I finally found a link that explained TOBS in a way that made sense to me. Apparently bias is only introduced if the time of day that the measurement is made changes. Am I to assume that NOAA actually knows this information and can correct for it in a meaningful way?
http://climateaudit101.wikispot.org/Time_of_Observation_Bias

Andrew

Anthony,
You deserve credit for putting your money where your mouth is!
Not everyone has the cojones to open yourself (and et al.) up to the public criticism for your work. Leading with your chin hurts sometimes, but I am glad you are willing to do so!

Christoph Dollis

The phase of the sampling periods is what I was trying to express…

Sure, but also the “observers” to use your analogy (or varying measuring times) aren’t going to be equidistant apart either.
The point is I just don’t know the magnitude of difference TOBS makes, but I know it isn’t likely to be a neat zero.

Think of TOBs this way:
Suppose for 5 years you take one temperature measurement a day at sunset. At that point you change the observation time to morning and for the next 5 years take daily measurements at sunrise.
If you take the measurements, turn them into monthly means, and calculate the trend over 10 years you will get rather biased results.

Kelly Haughton

It will be interesting to see what the “peers” do for the peer-reviewed journal. How will the peers be selected? What will they say? Will they read all the comments?

Steve Huntwork

“Sure, but also the “observers” to use your analogy (or varying measuring times) area’t going to be equidistant apart either.”
…………………..
Having been one of those trained monkeys that obtained the raw weather data at each and every hour, every day of the year, so I kinda know how things were done.
For some weather stations, the observer would record the maximum and minimum temperatures over the last 24 hours with those thermometers. He is human and was not willing to do this stuff at midnight every day. So, for human observers, the standard was around 8:00 AM each morning when there was enough light to even find the darn shelter.
For those of us who did this for a living, the observations were conducted every hour and summary reports were sent out to the World every six hours. The next morning, another team would perform “quality control” and insure that what we issued wa absolutely correct. And if not, then a message correcting the errors would be transmitted.

davidmhoffer

Entropic Man;
I see some papers to make one wince, too. Nevertheless, these are the ground rules that scientists and scientific journals go by.
>>>>>>>>>>>>>>>>>
It is indeed sad that otherwise intelligent people cling to the past that they are comfortable with. Odder still that someone would first promote peer review as the means to filter out bad science, and in the very next comment, admit that it doesn’t achieve that goal.
The fact of the matter is that there is a huge body of science that is published without the benefit of peer review nearly every day. The paper’s are called patents. Peer review journals do not and never did have any lock on the progress of science, the notion that they do is falsified every single day at patent offices all over the world. As for that portion of science that does progress through the journal system, I’m afraid you are stuck in the past. The world is changing, the internet permits for an exchange of information at a speed and cost that journals in their traditional format can never compete with. The only thing keeping them alive is the kind of attachment to the past the compels me to pick up an actualy newspaper from time to time to enoy along with a cup of coffee, despite my knowledge that the content was obsolete before it was printed, and current content from the same reporters is available instantly for a fraction of the cost on my desk top computer.
Will there be more crap on the internet because it is accessible to all? Of course. Will a tiny cabal of politicaly motivated scientists be able to get editors fired and legitimate science suppressed?
Not a chance. Welcome to the new world.

That TOBS is a PITA.
How many sites are there like this?comment image
There was 4 interpolated monthly data points, not in a CRS but a larger well ventilated enclosure, liquid in glass with 7 a.m and 7 p.m readings since day one, did have 4 moves to 4/10 of a mile from its original location.
http://climatetrends.colostate.edu/map?station=53005

Christoph Dollis

Cool Steve, thanks for the lowdown.
However, as Zeke points out, even if the recording times are tightly controlled, when they change, that’s going to skew things, so it should be accounted for in a perfect world. How much of a difference it makes to the end product I can’t say and will leave that for McIntyre and others to elucidate further.

Rob MW

Anthony,
I know you don’t have time for this question but I’ll put it any way, just in case.
If the paper was to somehow use a completely unadjusted TOB, would this then shift the focus of the paper into the area of “Unintended Consequences” (i.e. – debunking other papers in this area) and away from your et al. results that are achieved using contentious yet perpetuated TOB’s ??

A. Scott

Ron Broberg says:
July 31, 2012 at 5:47 pm
Anthony, when will the list of station ids used in this paper and their classifications be made available? And maybe some detail about how the classification was made?

I believe I have read a comment that this is being “addressed.” My inference is the information will be provided to select folks who can properly review it.
From my limited non-technical understanding the data is readily available publicly with the exception of Anthony’s siting results using Leroy 2010. This includes the raw and adjusted temp data along with the Leroy 2010 rating spec’s, which would allow anyone to do their own duplication of the work.
To me that seems preferable here – anyone attempting to duplicate should start from the beginning – rather then working backward from the conclusions.
The paper notes they applied the readily available specs of Leroy 2010 to the Fall 2010 USHCNv2 data set.
They identify the data they use: “We make use of the subset of USHCNv2 metadata from stations whose sites have been classified by Watts (2009)”. and “site rating metadata from Fall et al (2011)”. They further narrow: “Because some stations used in Fall et al. (2011) and Muller et al. (2012) suffered from a lack of the necessary supporting photography and/or measurement required to apply the Leroy (2010) rating system, or had undergone recent station moves, there is in a smaller set of station rating metadata (779 stations) than used in Fall et al (2011) and Muller et al. (2012), both of which used the data set containing 1007 rated stations.”. Steven Mosher and Zeke one would assume would have access to this station data as Watts used the same data as Muller 2012 in this regard.
They gave a description of the data used, their methods – how they calculated numbers – and presented their conclusions.
To me it would be much more relevant and useful it would seem, for those interested in replicating to follow the entire process – and see how their siting category counts came out. And only THEM compare to Watts conclusions.
I would also be interested in seeing how the USCRN stations, which were designed per Leroy 1999 (“which was designed for site pre-selection, rather than retroactive siting evaluation and classification”), fare under a review using Leroy 2010.
Watts 2012 notes “Many USHCNv2 stations which were previously rated with the methods employed in Leroy (1999) were subsequently rated differently when the Leroy (2010) method was applied in this study”…
Again, it would be very interesting, and potentially valuable, to see if the new USCRN sees the same siting quality results using Leroy 2010.

A. Scott

One more TYPO:
299 As in Fall, et al (2011), Menne (2010), and Muller (2012), only the heat source/sink
300 proximity and area ratings from Leroy 2010 and are do consider ground-level vegetation
301 or shade.
I suspect from the paragraph following that should say we only consider heat sink/source under Leroy 2010, and not shade or vegetation ….

Brad

Why not just offer a TOBS and non-TOBS graph with a discussion?

Jim Steele

Zeke Hausfather says: Think of TOBs this way:
Suppose for 5 years you take one temperature measurement a day at sunset. At that point you change the observation time to morning and for the next 5 years take daily measurements at sunrise.
That is not a good analogy Zeke.
That assumes the maximum and minimum is dependent only on whatever time the observation was made. I used minimum/maximum thermometers for 30 years. It didn’t matter when you read it. If the high was 70 F, it left the marker at that point as the temperatures then retreated. The only observer error that could happen, occurred if the observation was not done daily or if it was not made before the next maximum was reached.

Brad

Also, why isnt it possible to gets TOBS to be more exact? The sites should have evening temps even if morning temps are used in the database.

Steve Huntwork

Anthony, I have always supported your data quality control efforts. How anyone could object to efforts to insure quality control is beyond my comprehension.
What has happened between Steve McIntyre and you is none of my business. That is something that the two of you must work out.
But please, keep honest!

L.

Sorry if this has been discussed earlier, but has the Watt’s paper been dicussed on the ‘warmist’ sites yet..?
I had a look on desmog and realclimate, but couldn’t find anything.
I would be interetsed in a critique by people more qualified than myself.

Bill Illis

TOBS is a relatively newly discovered problem.
It was only discovered about 200 years ago.
The former Weather Bureau of the United States was already adjusting for it 1909.
http://babel.hathitrust.org/cgi/pt?id=uva.x030228867
110 years later, we are still making adjustments to temperatures of just 5 years ago apparently. Obviously, the dedicated weather-people of the United States did not know what they doing (in 1873 or in 2007).

Phil

Jason Samenow has rounded up early criticism/concern. Links below:
Josh Halpern/Eli Rabett
http://rabett.blogspot.com/2012/07/bunny-bait.html
Steve McIntyre
http://climateaudit.org/2012/07/31/surface-stations/

Gerry Parker

Anthony,
I agree with what you’ve done so far with regards to the stations, but there are additional points to consider. The entire premise by the team that an unknown signal mixed with an unknown noise can be descrambled by averaging, gridding, applying (seemingly) arbitrary offsets is beyond me. I have worked with some pretty sharp DSP algorithm folks descrambling noisy signals, and from my experience, there are too many unknowns for their approach to work. In fact, from my experience it is snake oil of the first degree.
Also, the mechanics of measuring the UHI of a city is something that is relatively trivial which I believe you have done yourself (recognizing it requires a lot of labor and some technology), so that is something that could factually be determined for many urban areas. The sectioning measurement could better determine the UHI affect on some of the stations by sectioning near the stations (although the ability to capture the dynamic nature would be limited since it would be one or more snapshots in time). This could be used to show that for X sections in a year, the average UHI near station Y was measured to be (some value). That seems much less arbitrary and based on measured data.
Gerry Parker

Zeke Hausfather says:

Suppose for 5 years you take one temperature measurement a day at sunset. At that point you change the observation time to morning and for the next 5 years take daily measurements at sunrise.
If you take the measurements, turn them into monthly means, and calculate the trend over 10 years you will get rather biased results.

You have got to be kidding!
Thanks to a little algebra, a monthly mean can be viewed as
MonthlyMean(j) = ((Sum of Max(i))-(Sum of Min(i)))/2, i = days(i) of month j
If I change the time of Observation from evening to morning, The most that happens is that I replace the High (from the last day of one month) with the High from the last day of the next month. And over the year, that will even out. For a 10 year trend you ought to see no effect at all.
And that assumes you have good meta data on the station and that the highs and lows were not already corrected in the record.
Ok. Maybe if you need the daily Max and Min to get a daily mean, to do something by day, you might need to sync the high and low values. But you don’t need to do this for Monthly means and multiyear trends.

Ron Broberg

A. Scott: To me it would be much more relevant and useful it would seem, for those interested in replicating to follow the entire process – and see how their siting category counts came out. And only THEM compare to Watts conclusions.
A., replication (aka “auditing”) requires the original data set. If Anthony feels it is appropriate to hold the data in private, away from public view, at least until publication, then the next step is to attempt to reproduce it by following his methods. Anthony explains above that he believes there is sufficient information in to reproduce their Leroy 2010 classification for USHCN stations. “We can, however, quite accurately determine heat sink coverage by use of satellite and aerial imagery and in particular, that of Google Earth aerial photography and its distance measurement tool.” That certainly tells us where the data came from, but only hints at how it was processed.
So neither Watt’s data nor his classification methods are currently available for public review. It’s important to understand the limits of this blog review. Nevertheless, I believe it could be possible to develop an independent classification per Leroy 2010 of USHCN stations.
REPLY: if you want to do that, since you are in Europe, why not start with GHCN instead of USHCN and contribute something useful and new as I did? There’s a whole mess of stations in GHCN just waiting to be rated right in your own back yard. – Anthony

scp

A thought, and maybe it’s wrong, but I’ll toss it out there – Instead of adjusting for TOBS, is there no way to slide the window so the day starts and stops at a different time? i.e. Offset the calendar by a number of hours to some different time zone in order to avoid the need for an adjustment?

Steve Huntwork

@scp says:
Now you are starting to understand what I was trying to say about the TOBS adjustments.
Lable the Y axis as temperature and the X axis as time.
The TOBS adjustments are along the X axis.
Amazingly simple if you think about it.
Slide the time window and the temperatures will match. It is that simple!

Ron Broberg

Europe? I guess even your penchant for revealing personal information of commentators is fallible! 😆
REPLY: Ron, Someone told me you were based in Germany, I took them at their word. So where are you based?
The suggestion still stands, there’s a need to get GHCN metadata/ratings. Apparently there was a group that was going to get around to doing it, but they have postponed to 2015. BTW my name is Anthony since you have trouble with that.
– Anthony

Eric Barnes

Reading the Karl TOBS paper here ftp://ftp.ncdc.noaa.gov/pub/data/ushcn/v2/monthly/karl-etal1986.pdf it would seem to me that you could experimentally determine TOBS bias for any site(s) that also had hourly data (the airports im assuming) based on an hour that you choose to reset the thermometer. IMO this would be a fairly easy way to bound the magnitude of the problem. Hasn’t anyone done that? Has anyone seen the tobs fortran code? I haven’t been able to find it.
Algorithm.
Use Hourly data to get min/max (reset at midnight).
Calculate max, min and mean values +trend.
Use hourly data but reset at 5pm say.
Calculate max, min and mean values +trend.
compare steps 2 and 4.

wayne

Christoph Dollis
Ummm, the difference is the temperature doesn’t fall and rise with the regularity of a Sine wave.

Christopher, a minimum is a minimum and a maximum is a maximum, please tell us all why you keep drawing time into the picture concerning this paper. Now if you are speaking of ~WWII changeover from single readings in the afternoon to single COOP readings at specific times in the morning I would see your point. This paper however is the 1979-2008 span. I would be surprised if any of the older single time readings even plays into this time period of records. See?

If you were to get maximum TOBS bias, you would read at the maximum temperature at about 3 in the afternoon. Then you would get a double high reading on a cooling trend. Unless the time of reading was changed often, you would just have one double reading and the rest a day off. Generally, people are a little curious about what the actual high temperature of the day might be. If I were reading the temperature, I might be incline to make sure I didn’t have the wrong temperature for the wrong day. The neighbors might start calling me an idiot or skeptic or something. I am sure that climate scientists considered the human element. Didn’t TOBS adjustments start when the geniuses realized the MMTS and the other automated system gave false readings? Oh, wait, they believed the high tech stuff first didn’t they?

MrX

Do any current thermometers keep monitoring temperature all day long and can I download this data anywhere? What sampling frequency is available? If anyone has a link to a handful of station data like this (preferably in Canada or the US), could you please post it? I’d like to do some simple analysis and also apply a possibly new algorithm for data that is cyclical (basically, it can detect shifts between the patterns, and/or give you some error analysis on slightly noisy data compared to a baseline or aggregate set of cyclical data, or even compare two sets of data)

Steve Huntwork

TOBS adjustments are kinda like dating an unknown sample of wood by matching the tree rings with known historical data to identify it’s date.
Archaologists do this all the time…

Eric Barnes

MrX says:
July 31, 2012 at 7:30 pm
Hourly data is here …
ftp://ftp.ncdc.noaa.gov/pub/data/noaa/

James Humbolt

[SNIP: James, I’m not going to get into this. I’ve had it with rude, hostile, superior, snarky and sneaky commenters. Sometimes you need to hit them with a two-by-four to get their attention. -REP]

Steve Huntwork

MrX:
You asked: “Do any current thermometers keep monitoring temperature all day long..”
There are so many sources of max / min thermometers available on the market today, that I could not hope to list all of them.
However, see if this link will help to answer your question:
http://www.bing.com/images/search?q=max+min+thermometers&qpvt=max+min+thermometers&FORM=IGRE

From the article:
In other news, Dr. John Christy will be presenting at the Senate EPW hearing tomorrow, for which we hope to provide a live feed. Word is that Dr. Richard Muller will not be presenting.
Muller is making the rounds. This afternoon he was a live guest on a.m. radio 910 in the San Francisco Bay area. The blurb I caught said: “Richard Muller, who was a skeptic funded by the Koch Brothers, has reversed his views…” [or something very close].
Muller the chameleon is still pretending that he used to be an AGW skeptic. I would call him a self-serving opportunist.

Rob MW

It seems to me that Anthony et al. will be damned by the climate science community if he uses unadjusted TOB’s, or damned by the skeptic community if he doesn’t.
Toss a coin Anthony and the rules are; heads you lose and tails you lose !!!

Paul Westhaver

much better-er… I like the graph. My brain responds to this form of representation.

Gunga Din

TOBs, Time of Observation biases. That was one of those terms I wasn’t familiar with and didn’t know what difference it might make until I followed the link above, “Steve has an older post on it HERE which can be a primer for learning about it.”
We report our precipitation to the NWS. One day a few years ago I took a call from them questioning our monthly report. We were taking our reading at about 6 AM and put it down under the previous days total. (Midnight was a very busy time for us, especially before we had any automation.) That was usually not a problem. The call was because there had been a heavy downpour between midnight and 6 AM on the first day of the month but nothing after 6 AM. Our report showed “0.0” precipitation while everyone else had a couple of inches at least. The time we took our reading had no effect on total for those two months but it did effect which of the two months it fell in.
I hope that might help someone understand what everyone is talking about when “TOBs” comes up.
(I’m still working on why it might matter that much to the paper.)

MrX says:
July 31, 2012 at 7:30 pm
“Do any current thermometers keep monitoring temperature all day long and can I download this data anywhere?”
Mr. X, click the icon on the right sidebar that says “Monitor your own weather”. Anthony doesn’t really push it, but his company sells numerous weather related instruments, including inexpensive usb dataloggers that can be set to record temps from very short to very long intervals.
I worked in a facility where almost every room had chart recorders for temp & humidity. The recorders and circular paper charts could be set for 1 day, 1 week, 1 month, etc. I am retired now, but I am sure there are models available. Ours were made by Honeywell. But Anthony’s are less expensive, and the versatility, specs & accuracy look to be even better than the paper chart recorders.