Guest Post by Willis Eschenbach
I got to thinking about the raw unadjusted temperature station data. Despite the many flaws in individual weather stations making up the US Historical Climate Network (USHCN), as revealed by Anthony Watts’ SurfaceStations project, the USHCN is arguably one of the best country networks. So I thought I’d take a look at what it reveals.
The data is available here, with further information about the dataset here. The page says:
UNITED STATES HISTORICAL CLIMATOLOGY NETWORK (USHCN) Daily Dataset M.J. Menne, C.N. Williams, Jr., and R.S. Vose National Climatic Data Center, National Oceanic and Atmospheric Administration
These files comprise CDIAC’s most current version of USHCN daily data.
These appear to be the raw, unhomogenized, unadjusted daily data files. Works for me. I started by looking at the lengths of the various records.

Figure 1. Lengths of the 1,218 USHCN temperature records. The picture shows a “Stevenson Screen”, the enclosure used to protect the instruments from direct sunlight so that they are measuring actual air temperature.
This is good news. 97.4% of the temperature records are longer than 30 years, and 99.7% are longer than 20 years. So I chose to use them all.
Next, I considered the trends of the minimum and maximum temperatures. I purposely did not consider the mean (average) trend, for a simple reason. We experience the daily maximum and minimum temperatures, the warmest and coldest times of the day. But nobody ever experiences an average temperature. It’s a mathematical construct. And I wanted to look at what we actually can sense and feel.
First I considered minimum temperatures. I began by looking at which stations were warming and which were cooling. Figure 2 shows that result.



Figure 2. USHCN minimum temperature trends by station. White is cooling, red is warming.
Interesting. Clearly, “global” warming isn’t. The minimum temperature at 30% of the USHCN stations is getting colder, not warmer. However, overall, the median trend is still warming. Here’s a histogram of the minimum temperature trends.



Figure 3. Histogram of 1,218 USHCN minimum temperature trends. See Menne et al. for estimates of what the various adjustments would do to this raw data.
Overall, the daily minimum temperatures have been warming. However, they’re only warming at a median rate of 1.1°C per century … hardly noticeable. And I have to say that I’m not terrified of warmer nights, particularly since most of the warmer nights are occurring in the winter. In my youth, I spent a couple of winter nights sleeping on a piece of cardboard on the street in New York, with newspapers wrapped around my legs under my pants for warmth.
I can assure you that I would have welcomed a warmer nighttime temperature …
The truth that climate alarmists don’t want you to notice is that extreme cold kills far more people than extreme warmth. A study in the British Medical Journal The Lancet showed that from 2000 to 2019, extreme cold killed about four and a half million people per year, and extreme warmth only killed a half million.



Figure 4. Excess deaths from extreme heat and cold, 2000-2019
So I’m not worried about an increase in minimum temperatures—that can only reduce mortality for plants, animals, and humanoids alike.
But what about maximum temperatures? Here are the trends of the USHCN stations as in Figure 2, but for maximum temperatures.



Figure 5. USHCN maximum temperature trends by station. White is cooling, red is warming.
I see a lot more white. Recall from Figure 2 that 30% of minimum temperature stations are cooling. But with maximum temperatures, about half of them are cooling (49.2%).
And here is the histogram of maximum temperatures. Basically, half warming, half cooling.



Figure 6. Histogram of 1,218 USHCN maximum temperature trends.
For maximum temperatures, the overall median trend is a trivial 0.07°C per century … color me unimpressed.
Call me crazy, but I say this is not any kind of an “existential threat”, “problem of the century”, or “climate emergency” as is often claimed by climate alarmists. Instead, it is a mild warming of the nights and no warming of the days. In fact, there’s no “climate emergency” at all.
And if you are suffering from what the American Psychiatric Association describes as “the mental health consequences of events linked to a changing global climate including mild stress and distress, high-risk coping behavior such as increased alcohol use and, occasionally, mental disorders such as depression, anxiety and post-traumatic stress” … well, I’d suggest you find a new excuse for your alcoholism, anxiety, or depression. That dog won’t hunt.
My very best to everyone from a very rainy California. When we had drought over the last couple of years, people blamed evil “climate change” … and now that we’re getting lots of rain, guess what people are blaming?
Yep, you guessed it.
w.
As Always: I ask that when you comment you quote the exact words you’re discussing. This avoids endless misunderstandings.
Adjustments: This raw data I’ve used above is often subjected to several different adjustments, as discussed here. One of the largest adjustments is for the time of observation, usually referred to as TOBS. The effect of the TOBS adjustment is to increase the overall trend in maximum temperatures by about 0.15°C per century (±0.02) and in minimum temperatures by about 0.22°C per century (±0.02). So if you wish, you can add those values to the trends shown above. Me, I’m not too fussed about an adjustment of a tenth or two of a degree per century, I’m not even sure if the network can measure to that level of precision. And it certainly is not perceptible to humans.
There are also adjustments for “homogeneity”, for station moves, instrument changes, and changes in conditions surrounding the instrument site.
Are these adjustments all valid? Unknown. For example, the adjustments for “homgeneity” assume that one station’s record should be similar to a nearby station … but a look at the maps above show that’s not the case. I know that where I live, it very rarely freezes. But less than a quarter mile (1/8 km) away, on the opposite side of the hill, it freezes a half-dozen times a year or so … homogeneous? I don’t think so.
The underlying problem is that in almost all cases there is no overlap in the pre- and post-change records. This makes it very difficult to determine the effects of the changes directly, and so indirect methods have to be used. There’s a description of the method for the TOBS adjustment here.
This also makes it very hard to estimate the effect of the adjustments. For example:
To calculate the effect of the TOB adjustments on the HCN version 2 temperature trends, the monthly TOB adjusted temperatures at each HCN station were converted to an anomaly relative to the 1961–90 station mean. Anomalies were then interpolated to the nodes of a 0.25° × 0.25° latitude–longitude grid using the method described by Willmott et al. (1985). Finally, gridpoint values were area weighted into a mean anomaly for the CONUS for each month and year. The process was then repeated for the unadjusted temperature data, and a difference series was formed between the TOB adjusted and unadjusted data.
To avoid all of that uncertainty, I’ve used the raw unadjusted data.
Addendum Regarding The Title: There’s an Aesop’s Fable, #35:
“A Man had lost his way in a wood one bitter winter’s night. As he was roaming about, a Satyr came up to him, and finding that he had lost his way, promised to give him a lodging for the night, and guide him out of the forest in the morning. As he went along to the Satyr’s cell, the Man raised both his hands to his mouth and kept on blowing at them. ‘What do you do that for?’ said the Satyr. ‘My hands are numb with the cold,’ said the Man, ‘and my breath warms them.’ After this they arrived at the Satyr’s home, and soon the Satyr put a smoking dish of porridge before him. But when the Man raised his spoon to his mouth he began blowing upon it. ‘And what do you do that for?’ said the Satyr. ‘The porridge is too hot, and my breath will cool it.’ ‘Out you go,’ said the Satyr, ‘I will have nought to do with a man who can blow hot and cold with the same breath.’”
The actual moral of the story is not the usual one that people draw from the fable, that the Man is fickle and the Satyr can’t trust him.
The Man is not fickle. His breath is always the same temperature … but what’s changing are the temperatures of his surroundings, just as they have been changing since time immemorial.
We call it “weather”.
Ja. Ja. I told. Maxima are dropping. Worldwide. I wonder why nobody noticed it? I am even battling keeping the temperature of my swimming pool up….
See fig. 4, here
https://breadonthewater.co.za/2022/03/08/who-or-what-turned-up-the-heat/
Note that in Table 1 of same report I show what is happening. It corresponds 100% with Willis’ observations. Minima are going up in the NH. But they are going down in the SH. Now look at the change in position of the magnetic north pole?
Henry Pool,
Temperatures from UAH satellite platfoms are dropping all over the world just now, but that does not allow a forecast of the future trends. Any month ahead can see a reversal of the present trend. You simply must expect a future warming trend, magnitude and timing unkown because the predictive efforts do not work. We do not understand enough about the causes of changes to temperatures like these. Geoff S
Geoff
Carefully look at table 2 of my report quoted earlier to understand why minima in the nh are going up. Here where I live, in Pretoria, minima went down by 0.8K compared to 40 years ago. The heat in the nh is not coming from the sun. It is not coming from the CO2. It is simply coming from inside…..
I live in Vermont, New England, US., already for 35 years.
During earlier years, we had lower temperatures in winter, such as -25F or -30F, near my house.
During later years, we had temperatures of -10F or -15F.
On average the US colder temperatures have not changed much, per the histograms, but that is not the case in New England.
It would be interesting, if Willis could verify that with histograms
Cold temperature records for Vermont are here. Winter temps look like this:
Per the LOWESS line, the change has been maybe 3°F (1.7°C) winter warming,
w.
Thank you, Willis.
I am astounded the difference is that little, about 3F over about 4 decades
Vermont’s and New Hampshire’s climate is colder from south to north.
I live near Woodstock, VT, near the middle
Hi Willis,
I have one more request.
Please add the Lowess line for the maxima.
That would give me some ammunition to try to change the minds of a few fence-sitting Legislators, who might be persuadable towards sanity
No worries, Wil. This thread is getting too long, check your email for the two graphs.
Best to you,
w.
Date to remember:
Great Blizzard of New York City on March 11 1888
https://en.wikipedia.org/wiki/Great_Blizzard_of_1888
Why is that a date to remember?
Probably no particular relevance. But interesting- a late winter blizzard to remind people nature is in control not man.
More relevant
Top 10 snow falls , most were blizzards too
6 of the 10 since the 2000s
http://www.weather2000.com/NY_Snowstorms.html
I think (more) snow forms when it is cooler. So the extra snow must be because of all that global warming….
Joe Bastardi is saying conditions next week are nearly identical to when that blizzard occurred.
Depends on who your date was.
Speaking of which, when is Anthony’s new temperature dataset that he announced at the conferences going to be up in running? I can’t wait to see how the media will react to that.
Also, February’s temperature for the USCRN just came with a +1.1 anomaly, which is colder than February 2005. I tried searching on the web for any articles and pieces from the media about the warmth back then and if it supposedly equates to catastrophic human caused global warming. I couldn’t find anything. Yet now there are articles like this:
https://www.cnn.com/2023/02/23/us/early-spring-record-warmth-impacts-climate/index.html
https://www.washingtonpost.com/business/50f-in-february-this-is-what-climate-change-looks-like/2023/02/15/7470c3f8-ad3f-11ed-b0ba-9f4244c6e5da_story.html
It just shows how misleading and desperate they are. This is literally brainwash.
You should not compare one month with another month
That is data mining
The USCRN trend is down since 2015
after being up from 2005 to 2015.
While an eight year cooling trend from 2015 to 2023 in the US does not predict the future Us or global climate, it does reveal a very important fact.
The largest 8 year increase of global CO2 emissions in history was accompanied by global cooling in the US, and very close to a flat trend globally (UAH data) for the past 101 months,
Looks like CO2 lost its imaginary job as the climate control knob !
The real problem with USCRN is that it did not come on line until 2005.
Richard,
My main point was that despite the fact that the winter of ‘04-‘05 was warmer than the winter of ‘22-‘23, there was no such ridiculous reporting connecting it to climate change back then. It just shows that they’re trying to scare people and they are stepping up their propaganda tactics even more now.
Climate change is 1% science and 99% trying to scare people to gain government power and control over the private sector.
“You should not compare one month with another month.”
Bingo. These “hottest month” pronouncements are not only meaning free, but provide legit – if convenient – targets for posters here. Since we have confidence limits for those GAT months, you can assess the probability of those “hottest month” pronouncements,. But even then, who cares?
“Looks like CO2 lost its imaginary job as the climate control knob!”
Not necessarily. It just demonstrates the importance of periodic oceanic trends to the cyclical, overall up trending, global temperatures since the waning of the mid century aerosol era. I realize that you deny the importance of that era climactically, but it is undeniable, above ground.
“ I can’t wait to see how the media will react to that.”
What makes you think they’ll even notice it?
What is the period these trends are measured over? Is it using the same period for all stations?
I ask, because it makes a difference. NOAA’s trends for USA:
1895 – 2014
Min: 0.8°C / Century
Max: 0.7°C / Century
1950 – 2014
Min: 1.8°C / Century
Max: 1.3°C / Century
1979 – 2014
Min: 2.1°C / Century
Max: 2.7°C / Century
If the apparent trend varies so much due to the choice of end points then you need to increase your error bars dramatically. Or consider the need to worry about a fluffy trend at all.
Or consider that warming over the last 125 years has not been linear.
I agree with Steve Richards. You always gripe about cherry picking end points. The variance in the trends you show how trending can mislead one. I am arguing with someone on twitter who declares the temperature data to be “noise” and the linear trend to be the actual signal. That is basically what you are doing also. As Steve points out, the error bars on your trends should definitely be large. Large to the point where the uncertainty in the trend prevents one from making any conclusions.
I spent 30 years in the telephone industry forecasting call growth, usage growth, usage from here to there, capital and expense expenditures, people, maintenance, etc. I learned early on that time series trends and smoothing were your enemy. Time is not a functional variable in any of those and it is not in temperature either. The ONLY way to make any headway in determining what causes variations in anything is to know what the actual inputs are and how they interact with each other. Modelers have tried to do this and fail miserably. Why do you think a time series trend when temps go up and temps go down will tell you anything beyond having your confirmation bias confirmed?
You realize that every one of your points could have been addressed to Willis Eschenbach. It’s his article. He’s the one drawing trend lines for every individual weather station in the US. He’s the one claiming on the basis of the median of all these stations, that the rate of warming is nothing to worry about. He’s not producing any uncertainty for these trend lines, or specifying what end points he’s using.
Sounds like you are concerned about scientific debate.
Just remember that a time series of temperature being trended does not prove any causation. If people aren’t enamored of your “trends”, maybe you need to consider why?
Debate? All you do is throw insults and demonstrate you’re inability to address the point. E.g.
“Just remember that a time series of temperature being trended does not prove any causation.”
I claimed absolutely nothing about causation, anymore than this article does. My point, was that you can’t just say “the trend” without specifying what period your trend is over. This is particularly addressed to the point int he article where it’s stated
“If people aren’t enamored of your “trends”, maybe you need to consider why?”
They are not my trends – I just pulled them off the NOAA website. Again, though the usual issue with your comments – why do you only object when I present a trend? Not when Monckton does it, not in this article, only when I report a trend do you suddenly go on about causation, or predicting the future or uncertainty etc.
Here’s the graph of maximum temperatures across the series, from 1895 – 2022.
Trend is 0.80 ± 0.25 °C / Century. (2σ confidence interval)
So statistically significant. But, as I say, it doesn’t represent a linear rate of warming.
Here are the time periods I used before, with their 2σ confidence intervals
1895 – 2014
Min: 0.80 ± 0.23°C / Century
Max: 0.65 ± 0.27°C / Century
1950 – 2014
Min: 1.77 ± 0.52°C / Century
Max: 1.25 ± 0.68°C / Century
1979 – 2014
Min: 2.1 ± 1.4°C / Century
Max: 2.7 ± 1.8°C / Century
Jim Gorman March 12, 2023 2:34 pm
Not clear why you claim this. Take for instance a time series of hourly temperatures. Temps assuredly go up and down, both hourly, monthly, annually, and decadally.
Here, for example, is a multi-year average of an hourly time series for Santa Rosa, CA, the weather station nearest to me.
This tells me lots of things. It tells me the lag between peak insolation and peak temperature. It tells me the average highs and lows. It tells me that cooling is much slower than warming. It tells me that cooling slows in the early morning hours.
You might compare it to a time series of my weight. Yes, time is not a variable in my weight … but I weigh myself daily, and whether I’m gaining or losing weight assuredly tells me something.
As I said, not sure what the basis of your claim might be.
Regards,
w.
It is as simple as your weight. A trend doesn’t necessarily predict what is going to happen. It can tell you what has occurred but since time isn’t a functional variable determining your weight, you need to know what functional variables are controlling your weight in order to have an idea how it will change and if it will follow the established trend.
When I look at UAH, I see temps increase then fall back to the base line. I also see that they have decreased and gone back up. That simply can’t happen under a constantly increasing CO2 if CO2 is the controlling variable.
My preliminary investigations point toward seasonal changes as partially causing spurious trends. Averaging NH and SH likely have an effect on spurious trends also.
I learned early in my career that simple linear regression based on time is most likely going to give incorrect answers when predicting. I am seeing too many locations that show no warming and even cooling to all of a sudden start believing in linear regression based on averages of averages of averages as a panacea for forecasting future temperatures.
Jim Gorman March 13, 2023 3:42 pm
A trend in my weight absolutely predicts what is going to happen unless something changes in my eating and exercise habits.
You’re right, it doesn’t tell me what the “functional variables” are or how to control them… but that doesn’t mean it’s not a very valuable predictive measure.
Which is why I weigh myself every morning buck naked, to see which way my weight is trending. And observing those trends is why I’m only five pounds heavier than when I graduated high school.
Yes, you’re right, linear trends are wildly overused … but that doesn’t mean they’re useless.
w.
I’ll just point out that experience has taught me that trends, especially linear trends, will bite you on the butt. They are only good to show where you have been.
I know that you know what goes into your body and can therefore have a good idea what is going to happen. My point is how many people forecasted the current pause the CMB is tracking? How many people have gone on the record about when it will end? As Nick pointed out above, a lot of people think the current linear trend will continue and maybe even get steeper until the earth literally burns up. That is what trends are good for. The SVB bank near you probably used a similar method to track their viability.
I might as well continue the “debate” here.
“You always gripe about cherry picking end points.”
As should anyone. Monckton used to get very self righteous about “the end-point fallacy”, pointing out how carefully choosing your endpoints to get a result you wanted was a bogus statistical technique.
I’ve also griped about looking at a linear trend over non linear data, and making claims about the strength of that trend.
“The variance in the trends you show how trending can mislead one.”
I wasn’t making any specific point about those three periods. Just trying to get an answer to the question, over what period are the trends in this article calculated. I think this is an important question because the trend is being used to argue that the rate of warming isn’t a problem.
“I am arguing with someone on twitter who declares the temperature data to be “noise” and the linear trend to be the actual signal. That is basically what you are doing also.”
How? I’m pointing out the trend varies over different periods. It’s not possible for both the trend from 1895 and the trend from 1979 to be “the actual signal” when they are different.
“As Steve points out, the error bars on your trends should definitely be large.”
I’ve calculated the confidence intervals for all the trends below. As expected they get larger over shorter periods, but none of them indicate the warming trend isn’t significant.
But, as so often, you just assume they “should definitely be large” without doing the calculations for yourself.
“Large to the point where the uncertainty in the trend prevents one from making any conclusions.”
No. See above.
Continued.
“I spent 30 years in the telephone industry forecasting call growth, usage growth, usage from here to there, capital and expense expenditures, people, maintenance, etc.”
You keep saying this, and I’m sure I’ve suggested to you that the telephone industry and global temperatures may not work in the same way.
“I learned early on that time series trends and smoothing were your enemy.”
Or maybe, you just weren’t very good at understanding them.
“Time is not a functional variable in any of those and it is not in temperature either.”
And we’ve been over this numerous times before. 1) Time is a dependent variable (assuming that’s what you mean by functional; variable) is the function you are interested in is how does something change over time. 2) Nobody is suggesting that time causes the change, just that things change over time, and that suggests something is cause the change.
“The ONLY way to make any headway in determining what causes variations in anything is to know what the actual inputs are and how they interact with each other.”
As I’ve agreed with you on many occasions. If you want to understand and predict how changes occur, than you need to understand the why. Statistics won’t prove why something is happening, but they can give indications, and they can be used to provide evidence for a particular hypothesis.
“Modelers have tried to do this and fail miserably.”
That’s your belief.
“Why do you think a time series trend when temps go up and temps go down will tell you anything beyond having your confirmation bias confirmed?”
I’m not sure what particular bias you think I’m trying to confirm here. If I wanted to talk about global warming I wouldn’t be looking at US temperatures. I’m specifically making the point that a linear trend over temperatures that are going up and down like they are in the US data, is not a reliable indicator of what is happening, or what will happen.
You missed the entire point. A trend based in time, when time is not a functional variable, leaves you blind as to what the variables that determine the trend. Did your trend forecast the pause we are currently experiencing? If not, why not? Did your trend forecast any of the excursion up or down? why not.
All your trends can tell you is that something has caused both warming and cooling to occur. You have no data to explain what the causes were and where the future will go. Does that sound like the GCM’s that turn linear and just keep growing? Does any GCM forecast when temps will level off? Does your trend, or do you believe we are destined to burn up?
“Did your trend forecast the pause we are currently experiencing?”
You realise your hypothetical pause is also a trend line based on nothing but time?
As I’ve said before the trend line up to the pause would have predicted cooler temperatures than we’ve seen int he last 8 years.
“Did your trend forecast any of the excursion up or down? why not.”
Of course not. Because it’s linear.
But the point of this or any other regression is not to predict every up and own. It’s to indicate what the overall change has been.
Again, here’s my linear regression using just CO2, ENSO and a volcanic index.
“I learned early on that time series trends and smoothing were your enemy.”
Yeah, I am sure I just wasn’t smart enough to understand what a straight line was showing for growth. It only takes meeting with the boss one time to discuss missed forecasts to learn what those straight lines really meant. You obviously have never had one of those meetings after missing forecasts.
For your own education, there were any number of factors that needed to be considered, not unlike temperature. Government funding of all kinds, layoffs, new businesses, recessions, population changes, and on and on. If you didn’t do the research properly and just relied on what the past did, you were screwed.
“It only takes meeting with the boss one time to discuss missed forecasts to learn what those straight lines really meant.”
That’s my point. If all you did was project a linear trend would continue into the future, you were not very good at forecasting. Hopefully you learnt from your mistake.
“For your own education, there were any number of factors that needed to be considered, not unlike temperature.”
I love how you keep trying to “educate” me on things I keep showing you. I keep showing you my simple linear models based on any number of things that might affect global temperatures. And, as I kjeep saying, if I was trying to predict the future I wouldn’t rely on that. I’d want an actual physical model, and that wouldn’t be enough to predict the future. It would require knowing how much more CO2 is going to go into the atmosphere along with any other factors, which is not something you can predict.
If that is truly the case, then what are you trying to accomplish when discussing your trends. If they can’t be used to forecast, just show the data and forget the trend. It is meaningless by your own admission.
As I keep saying, I’m using them to determine the rate of warming. And in this case to illustrate that the more recent trend was faster than the trend since 1895.
I’m not saying the trend can’t be used to forecast. But it’s not going to be a very accurate forecast, especially if you project it too far into the future.
Probably mostly due to UHI. That would explain the difference between the trends. UHI is more significant at night.
USCRN numbers are similar to NClimDiv numbers
The rural USCRN weather stations allegedly have no UHI
So how much UHI could possibly be included in the similar NClimDiv numbers?
UHI affects cities of all sizes to some degree. The siting issues are different from UHI.
https://www.drroyspencer.com/2023/02/urbanization-effects-on-ghcn-temperature-trends-part-ii-evidence-that-homogenization-spuriously-warms-trends/
USCRN weather stations are claimed to be perfectly sited rural weather stations, NOT affected by UH I, not needing adjustments, and not needing infilling because temperature data reporting is automated. That sounds too good to be true, so maybe it is not true?
It is my opinion, the integrity of the PEOPLE who compile the national average temperature are just as important as the quality of data they have. And I do not trust NOAA.
The operative words in your post are “claimed to be perfectly sited”.
UHI affects can be seen downwind of UHI sites for miles, at times 20 miles or more.
Do you ever wonder why the variance of the temperature data sets is never addressed? The variance of truly rural sites will be different than the variance of those with UHI impacts.
USCRN stations should be capable of providing 5min data or even 2 minute data. Heck, my Davis Vantage Vue weather station can do that! It should be able to analyze the resulting profiles to see if there are any impacts from wind-related UHI caused by variable weather.
Of course with this kind of data it would be better for climate science to join the 21st century and begin to use integral-based degree-day analysis for each station.
See the image. If accuracy, is ±0.3C, how does anything below this ever get reported? Averaging simply does not change the precision to which measurements are actually made.
This sounds about right. More energy is used heating buildings at night than during the day, and the larger temperature gradient at night would accelerate heat losses to the outside air.
The map for the trends in the maximum temperature is interesting. Most of the stations where daily maxima are decreasing are in the Southeast and Midwest, while the stations where daily maxima are increasing are in the desert southwest, the Northwest, and Northeast.
In the Southeast, where the climate is generally warm and humid anyway, days are getting cooler, while the generally cooler climates in the northern states are getting warmer, which would tend to lengthen growing seasons. If such trends continue, this would lead to smaller temperature gradients between north and south, and tend to decrease the frequency of strong storms.
As for the desert southwest, could the daytime warming be the result of increasing urbanization (for example, Phoenix or Las Vegas), where asphalt and concrete absorb sunlight better than natural soil in the desert?
I think this analysis was far from complete, which is rare for Willie E.
First Problem
How can one be sure that raw “unadjusted” numbers are really raw and unadjusted?
One would have to trust NOAA to be confident.
I don’t trust NOAA, do you?
NOAA has two different weather station networks, NClimDiv and USCRN, with completely different siting, yet they somehow manage to show almost the same temperature trends.
Is that just a coincidence, or is the fix in?
That is very suspicious to me.
My general rule of thumb is to NOT trust government politicians and bureaucrats.
I do trust Roy Spencer and John Christy for UAH data — they are volunteers who do not have any financial incentives to show more warming than actually exists in their data.
Second.Problem
Are the known arbitrary adjustments in the numbers shown to the public really completely missing from the raw “unadjusted” data?
For example, the mid-1930s included the hottest US year for a long time. Hotter than the initial 1998 number. Then there were arbitrary adjustments and 1998 became warmer than any year in the 1930s. It that arbitrary adjustment also included in raw “unadjusted” data?
Third Problem:
While a weather station may be listed as being in community A. What if it was moved from downtown Community A to the out of town Community A airport? That move is really a new weather station, in a different environment, even if still listed as “Community A” weather station. How about a weather station moved to one or more different locations within the Community A over many decades? Maybe Community A had a weather station for 120 years, but it was moved four times in those 120 years?
Would you still call it a 120-year record weather station?
Fourth Problem:
There are many estimates included in the so called raw numbers, called infilling. Tony Heller, at his website, claims the estimated (infilled) data are a large percentage of USHCN data. if he is correct, the alleged raw data are not raw data at all. They are a mix of raw data and wild guessed numbers, with the guesses coming from government bureaucrats who are likely to be biased to want to see more warming.
61% Fake Data | Real Climate Science
In my opinion, are few real data in the average US temperature statistic
There are mainly adjusted numbers and infilled numbers
Those are not data
Only raw unadjusted measurements are data.
The big question is what is actually included in the statistical average US temperature that NOAA tell the general public:
The percentage of raw unadjusted numbers?
The percentage of adjusted numbers?
The percentage of infilled numbers?
Without answers to those three questions, all we know is the average US temperature is whatever NOAA tells us it is, and there is no way we can verify if their average is correct.
I’m not sure that those problems are significant.
#1. How can one be sure that raw “unadjusted” numbers are really raw and unadjusted?
They are the rawest we have. They don’t have to be 100% raw in order to be different to the official numbers or interesting, just rawer. If even rawer numbers become available, I’m sure that Willis will tell us about them.
#2. Are the known arbitrary adjustments in the numbers shown to the public really completely missing from the raw “unadjusted” data?
The paper describing the data does indicate that the data is of the actual station readings.
#3. While a weather station may be listed as being in community A. What if it was moved from downtown Community A to the out of town Community A airport?
The same paper also states that station moves were a factor in selecting the stations. So we can reasonably assume that if there were indeed any station moves then there were fewer station moves in the selected stations than in others.
#4.There are many estimates included in the so called raw numbers, called infilling.
The same paper states that there are both daily and monthly numbers. Infilling for a station would be used for monthly numbers where daily data was missing. Willis uses only the daily data. Maybe Willis can confirm whether some daily values are missing, in which case there is likely to be no infilling in the daily data. In any case, if there is any same-station infilling then it is surely likely to be consistent with any trend in the station’s actual measurements, That’s very different to homogenisation, where a station’s trend can easily be influenced by different trends in other stations.
No-one is claiming that the data used by Willis is as pure as the driven stuff that children don’t know any more. The data is different to the homogenised official data, and it’s interesting. That makes it worth analysing, and I thank Willis for doing the analysis.
“The same paper states that there are both daily and monthly numbers. Infilling for a station would be used for monthly numbers where daily data were missing.”
It is hard to believe that infilling would be used for monthly numbers and not for daily numbers. It would seem to me that missing daily numbers would have to be infilled to compile a monthly average temperature.
I still have the largest potential problem (4) reported by Tony Heller,
claiming a majority of USHCN numbers are estimated, which means infilled. And the estimated, infilled numbers themselves have a steep warming trend. Very suspicious.
If that is anywhere close to being a true percentage of infilling, then the data are not fit for any scientific analysis.
“It is hard to believe that infilling would be used for monthly numbers and not for daily numbers.”
There are two different notions of infilling here. The one referred to here is infilling in time. If days in the month are missing, some expected values derived from data for the same station are used to infill before averaging. That is much better than the common device of just leaving them out of the average. But obviously, you can’t do that for daily data.
The other notion is spatial, where nearby stations are used to provide an estimate. That is never done for USHCN raw or GHCN unadjusted.
RG said: “I still have the largest potential problem (4) reported by Tony Heller,”
Keep in mind that it was Tony Heller’s insistence that you didn’t need to grid and infill data that sparked the controversy getting himself banned from WUWT. Even Anthony Watts knows that you must grid and infill data to produce a spatial average.
RG said: “claiming a majority of USHCN numbers are estimated,”
No they aren’t.
RG said: “which means infilled.”
As Nick points out there are two notions of Infilling. The one that is most relevant to the discussions is the spatial infilling or the interpolation of grid cells without an assigned observation.
RG said: “And the estimated, infilled numbers themselves have a steep warming trend.”
In the US the infilling doesn’t matter much. It is the TOB and instrument change adjustments which make the trend higher relative to the raw data. This is because both the TOB changes and instrument changes put a low bias on temperature measurements [Vose et al. 2003] [Hubbard & Lin 2006].
RG said: “If that is anywhere close to being a true percentage of infilling, then the data are not fit for any scientific analysis.”
Infilling is inevitable when doing a spatial average. You can’t avoid it. The no effort biased strategy is to assume the unfilled cells behave like the filled cells. This is often handled implicitly like is the case with NOAAGlobalTemp v5.0 and lower and HadCRUTv4 and lower which have less than 100% spatial coverage but call it a “global” value anyway. Other datasets like GISTEMP, BEST, and yes even UAH do the infilling explicitly with locally weighted strategies. The idea being that a grid cell is behaves more like it’s neighbors than with the average with of the entire globe.
That was a lot of tap dancing saying nothing of value, and sounding like you are a NOAA employee.
Tony Heller reports that a majority of USHCN numbers are estimated (infilled), and the infilled numbers show a sharp warming trend NOT seen in the measured raw numbers.
That suggests infilling has a warming bias.
Either Tony Heller is right
or Tony Heller is wrong.
You obviously have no answer.
You character attacked him but
conveniently avoided my question.
I want to know what percentage
of USHCN numbers are infilled,
The answer requires a percentage
A number
Not your “no they aren’t” claim
Not an explanation of what infilling is.
If you don’t know, just say: “I don’t know”.
And if you don’t know, your conclusion that:
“In the US the infilling doesn’t matter much”
is your speculation, NOT a fact.
“I want to know what percentage of USHCN numbers are infilled”
Very imprecise. Do you mean
1) % of raw data – answer 0%
2) % of adjusted data – probably his count of 61% is right.
But the thing is that USHCN was replaced by nClimDiv nine years ago. It has not been used since then in any NOAA published work. It is true that they have kept posting data from USHCN stations on a file on the internet; they have not closed that system down. But they have not made efforts to keep those stations reporting. Why should they? That system is obsolete. They now have a bunch of 10,000 stations that is what they actually use.
Of course the Raw Data has been adjusted.
You only need to compare the Raw data from GISS V2 to the raw data for GISS V4.
Because of course V4 has been Quality Controlled.
If there are versions,
then something has changed.
If there are no changes,
then there would be only ONE version.
They are trying to snow you. They are statisticians and not physical scientists. Infilling creates more data points than are actually available thus making the distribution look more peaked around the “average”. To a statistician this means the data “looks” more accurate, i.e. a smaller standard deviation.
All it does is spread UHI and measurement uncertainty around making the data *more* unreliable, not more reliable.
Excellent comments, Richard. Excellent questions.
“Infilling is inevitable when doing a spatial average.”
Malarky. All the infilling does is drive the temperature toward the average. It hides the true variance in the actual data by adding data points that are actually unknown. Infilling SPREADS UHI impacts and measurement uncertainty over other stations.
I’ve given you the study by Hubbard and Lin before in other threads that show that adjustments (i.e. infilling) on a regional basis are just not acceptable. They must be done on a station-by-station basis.
The average of the data you *have* is what is scientifically acceptable. Anything else is just guesswork and not fit for purpose.
“NOAA has two different weather station networks, NClimDiv and USCRN, with completely different siting, yet they somehow manage to show almost the same temperature trends.”
The conspiracy notions here are nuts. Firstly just on the common sense grounds. nClimDiv has over 10000 stations. That is, just for a start, over 10000 people who would know if their data was being fiddled to match. Then of course, there are FOI, OIGs etc. You may dislike how bureaucracies work, but they just can’t work that way.
But second, the station data are published as soon as read. Here is a NOAA site which has both USCRN and nClimDiv, updated every hour, at least. How do you imagine data fiddlers are getting to it before posting? It is clearly coming straight from AWS; there is too much data for human processing. But they wouldn’t even know what USCRN stations were showing before their own station data had appeared.
“Are the known arbitrary adjustments in the numbers shown to the public really completely missing from the raw “unadjusted” data?”
Same thing. The raw data hasn’t changed. Pre-1990 data was recorded in GHCN V1 and distributed on DVD. Data this century was posted almost as soon as read. You can track it, as I showed in a WUWT post for Australia.
“There are many estimates included in the so called raw numbers, called infilling.”
Untrue. Raw data was measured at that station only. Again, you can check the station records. NOAA even posts facsimiles of the hand-written data from olden times.
You can’t compute a monthly average temperature without infilling
Therefore, raw data are incomplete until missing daily data are infilled,
Your blind trust in NOAA, and all other government data, has been noted here before. I do not have that confidence in government data on Covid, Covid vaccines, government censorship, climate change, Nut Zero temperature averages, etc. This website is popular because of the mistrust of government data and claims. We are obviously on opposoite sides of this subject.
The 1940 to 1975 global cooling, as reported in 1975, was revised away by NASA-GISS. I know NASA-GISS is not NOAA, but there is no logical reason to trust government temperature averages. There are too many temperature revisions made after the week of the initial measurements.
“You can’t compute a monthly average temperature without infilling”
Well, you can if none are missing. Else the missing are estimated by interpolation of the station time series.
“ there is no logical reason to trust government temperature averages“
OK, then do it yourself. Here is my Feb 2023 estimate. GISS will be out in a few days. It will be much the same, even though I use unadjusted GHCN data.
“ Else the missing are estimated by interpolation of the station time series.”
You are dissembling, something you are very good at. The issue isn’t infilling *station* information, it is using data from station A to estimate the temperature at station B.
Hubbard and Lin showed clear back in 2004 that is unacceptable due to microclimate differences between stations.
As I spelt out here, for raw data the only thing done is time infilling when calculating monthly averages. Spatial infilling is not done.
bdgwx: “Even Anthony Watts knows that you must grid and infill data to produce a spatial average.”
Nick, you and bdgwx need to get together and get your stories straight.
There is no reason for infilling daily data in order to calculate a *monthly* average at a specific measuring station. Daily median values only use Tmax and Tmin. If you are missing those for a day are you going to *guess* at what they actually were? Since they are at an inflection point you can’t use “interpolation” to find out what they were. Or are you just going to use the rest of the days in the month to get an average?
Of course you must grid and infill data to get a global average. That is an average for the globe, and so you must estimate what lies between the sample points.
But you seem unable to handle the most elementary distinctions. I said that raw data is not infilled. That is, in the supplied data set. Of course people may do so themselves later.
Once again, pure malarky! Infilling data only creates more data points having the average value – thus making the distribution have a smaller standard deviation. It is statistical hocus-pocus!
The word “estimate” is synonymous with the word “guess”. Guessing temperatures is a fraud! That’s why Hubbard and Lin found that you couldn’t use regional adjustments. The micro-climates between stations can be vastly different.
You use the data you have. Period. Exclamation point!
You don’t guess the temperature on top of Pikes Peak is the same as in Colorado Springs merely because they happen to be in different grids. Your guess would be wildly wrong.
See the attached graphic. If you didn’t know the temperature in Osage City would using the temp in Topeka provide a valid “estimate”? It would be off by several degrees!
Just use the temperatures you have and be done with it.
Tim Gorman March 13, 2023 11:48 am
Perhaps you are foolish enough to infill by adding “more data points having the average value”.
Protip—sane people do not infill in that manner.
Note that many of the infilled points are FURTHER from the average than the actual points. And the splined data points are not an average of anything.
w.
“Perhaps you are foolish enough to infill by adding “more data points having the average value”.
Protip—sane people do not infill in that manner.”
Isn’t that essentially what happens if you don’t infill? You assume all the missing data is the same as the average.
“You can’t compute a monthly average temperature without infilling”
Sure you can. How much effect do you think 2 or 3 days or even more has on a monthly average?
Temperatures are highly correlated, especially daily averages. Can you have a large change in between two days, sure. However, as long as the missing temps are random, over time, there isn’t a major effect.
Jim Gorman March 12, 2023 6:26 am
Those who know me know that I much prefer data to theory. Here are the results for a random month of USHCN minimum temps with one to five days randomly removed.
As you can see, with up to three days missing your result will be within ± 1°C of the true average, and in all cases shown, 95% of the results will be within ± 1°C of the true average.
Now, how about infilling? There’s been a lot of speculation about whether it should be done or not … me, as I said, I prefer data to speculation.
Here’s 1,000 reps with one day missing, either without infilling or infilled with the average of the previous and following days.
The heavy black horizontal lines are the medians of the data. As you can see, infilling both decreases the spread and increases the accuracy of the results.
Glad to help, and please, folks, DON’T MAKE CLAIMS UNTIL YOU ACTUALLY RUN THE NUMBERS!!!
w.
“The heavy black horizontal lines are the medians of the data. As you can see, infilling both decreases the spread and increases the accuracy of the results.”
The “accuracy” is just a phantom. It’s created by inserting more data points close to the “average”. It makes the standard deviation look as if it is smaller. It makes the distribution more peaked around the average.
That’s not a real increase in the “accuracy”. It’s like walking up to an archery target and sticking a bunch of extra arrows by hand into the bullseye and saying that your accuracy has gone up as a result.
Tim, I have NOT “inserted more data points close to the “average”” as you incorrectly claim. Nor have I “stuck a bunch of extra arrows by hand into the bullseye”. That’s simply not true.
Instead, as I clearly stated, I interpolated by inserting values that were the average of the previous and the following days.
However, now that I think about it, I suspect I could get a better result by infilling using a spline rather than a linear interpolation as above.
If I apply both procedures to an entire month, knocking out the data points one by one and replacing them with interpolated points, I get this result.
Note that contrary to what you said, in a number of points the interpolation is further from the mean than the actual data, thus falsifying your claim that I’ve just “inserted more data points close to the average”.
Clearly, you will get a more accurate average by infilling than by leaving the gaps, and spline infilling will give a more accurate answer than linear infilling.
Best to you,
w.
This the first time I see the term spline infilling.
I have always used linear infilling
Yeah, wil, it’s likely because I just invented the term and the procedure. Probably not the first time it’s been invented, but certainly new to me.
Now I’m thinking about an even better method. Stay tuned, I’ll post about it if it works.
w.
I would be interested in how the variance changed by performing the infilling. If the variance changes, then the distribution is different.
I think what Tim was pointing out what would happen if you infilled with the “monthly average”. Using surrounding days would give a different affect.
The problem with infilling, even with an average of the surrounding days is that there is no way to know if that is an accurate value. It may be that it should be closer to the preceding temp or closer to the following temp. Who can know?
The preliminary work I am doing doesn’t show a large problem with changing variance by simply using the days that are available. Over a number of years, the variance in same a same month distribution appears to be within the range of variance.
The image I have attached has RSS as Root Sum Square. The variances have been calculated based on the NIST TN 1900 Example 2 method of determining the expanded uncertainty. As you can see the uncertainties haven’t changed much over the years.
I will add before someone else does, that for this station, there are a number of missing years, like 1970 to 1999. However, it doesn’t appear that either anomaly values nor their uncertainty have had drastic changes over the years.
“Instead, as I clearly stated, I interpolated by inserting values that were the average of the previous and the following days.”
You interpolated by using an average value. You *added* data points that you didn’t actually measure. In other words you guessed.
Attached is a graph of the temperatures at my weather station for the past 30 days. Yes, on some days you could average the day before and the day after and make a good guess at the temperatures. On other days you would be wildly wrong by doing that.
If your “average” interpolation method works then just averaging the actual data you have should give almost the same answer. If you sample 20 days out of 30 and get a different average from those 20 data points than you do by “infilling” the missing 10 data points then there is something drastically wrong with your sample to begin with.
I should also point out that you are speaking of infilling at ONE specific measurement station. That is vastly different than using the measurement made at station A to infill a missing value at station B in order to just have a value to put in an empty grid.
I did experiments similar to what Willis did here and here. Similar result, infilling is good. I didn’t try splines, though.
Thanks, Nick. Your examples and explanations are quite clear.
What folks don’t seem to get is that replacing missing data with “NA” actually IS infilling, you’re just infilling with NA … and that you’re better off to infill with almost anything but that.
As to splines, it was something I just thought up when I was halfway through creating my graphic example above. And when I tried it, it improved the answer.
I’d also suspect that my Fourier method, which unlike standard Fourier allows for missing data, might also do quite well for infilling … haven’t tried it yet though.
w.
Thanks, Willis
“actually IS infilling, you’re just infilling with NA “
There is a bit extra to that, which I find useful. It is arithmetically equivalent to infilling with the average of the points for which you do have data. So if it is a colder or hotter place than the average, that will correspondingly be a bad choice.
The way I usually describe it is that when you leave a cell unfilled and do the trivial average of only the filled cells you have only produced a spatial average that is a subset of the whole. For example, if NOAAGlobalTempv5.0 has 20% of its cells unfilled then the grid average is for only 80% of Earth. That’s not strictly “global”…obviously. But if you then use that 80% figure as a proxy for the whole you are effectively infilling the remaining 20% of cells with the average of the filled 80%. That gets you to the 100% and now you can rightfully call it “global”. This is what I mean when I say infilling is inevitable. The question is…do you want to infill using a local strategy (like kriging) or a non-local strategy where you effectively assume the unfilled cells behave like the average of the filled cells.
Willis it is a little more than that. You only did a part of an experiment to determine the affects of infilling. Here are some questions.
Too many folks that post here about averages just blithely ignore distributions and variance. You posted frequency charts in your essay. Have you examined those for monthly values. From my investigations, few months, unless you’re near a coast, have normal distributions. Plot the mean on those charts and you can recognize the skewness and kurtosis that is there. Two more statistical parameters that are never discussed.
To many of the folks posting here are focused entirely on doing averages only. Let’s average this, or adjust that to get a better mean, maybe homogenize regardless of what it does to the actual distribution and variance.
One should ask themselves why medical research papers, physics research papers, and other scientific papers delve deeply into the statistical parameters and how sampling is done. Even political pollsters have better statistics than we see in climate science.
After studying Dr. Possolo’s paper that is published by NIST, I have a better understanding and appreciation for the steps he used to calculate a mean temperature in TN 1900. I have also obtained his book and studied it. One can easily understand why he makes the assumption that systematic and random measurement errors are negligible when compared to the variance in Tmax and Tmin throughout a month. Using his method, most months have an expanded uncertainty @95% confidence of ±2 -4°C. You never see a variance like this quoted here.
Jim, yes, the distribution changes. But you’re looking at the wrong comparison. You’re comparing the distribution with the missing value with the distribution with the infilled value.
Instead, you should be looking at the distribution with the infilled value compared to the distribution with the actual value. Do some experiments knocking out a value. Here’s an example comparing standard deviations
> sd(c(1, 4, 5, 4, 2)) #Original Data
[1] 1.643
> sd(c(1, NA, 5, 4, 2), na.rm=T) #2nd Value Removed
[1] 1.826
> sd(c(1, 4.25, 5, 4, 2)) #Spline Infilling
[1] 1.677
You are 100% correct that the interpolation changes the distribution. But what you fail to note is that the infilled distribution may well be closer to the actual distribution.
Often this process can be aided by the cyclical nature of many weather datasets. Here’s two months of CERES surface temperature data. I’ve knocked out the first July, and then replaced it with spline infilling. (Note that in this example, spline infilling is much better than linear infilling … but I digress).
Here are the standard deviations.
> round(sd(shortemp),3) # original CERES data
[1] 1.372
> round(sd(shortna,na.rm=T),3) # July data omitted
[1] 1.352
> round(sd(splinena),3) # spline infilling
[1] 1.375
Again, you’re right. Infilling changes the standard deviation, from 1.352 to 1.375 … but it brings it much closer to the actual data distribution than you get by just leaving the data omitted.
Best regards,
w.
A long answer but I want people to understand where I am coming from.
I understand what you are doing. I have not looked at what occurs with missing entire months of data that are missing. All of my investigations have looked at missing days within a month.
As you can see from the image I previously posted, the expanded uncertainty for each individual month, as calculated using NIST TN1900, has little variation. You simply can not tell which months have missing days by looking at the values.
I also need to point out that the statement of uncertainty has rules for significant digits also. From this web site:
Microsoft Word – Uncertainties and Significant Figures.doc (deanza.edu)
Since your data values are integers and have 1 significant digit, the uncertainty should be rounded to 1 significant digit at the units place.
For example:
(1, 4, 5, 4, 2) => mean = 3
stated answer => 3 ± 2
We can evaluate this using the TN 1900 method.
1.643/√5 = 0.73
k factor for (DF = 5 – 1) @ 97.5% = 2.776
0.73 * 2.776 = 2.02 => 2 @ 95% confidence interval
stated answer => 3 ± 2
We get the same expanded uncertainty. Isn’t that amazing?
Let’s do it for the 2nd set – minus one value
(1, NA, 5, 4, 2) => mean = 3
1.826/√4 = 0.91
k factor for (DF = 4 – 1) @ 97.5% = 4.541
0.91 * 4.541 = 4.13 => 4 @ 95% confidence interval
stated answer => 3 ± 4
Whoa! Why is this? The fewer values you have, the larger the uncertainty. Let’s look at a number set with 30 values, then remove tfour of them.
(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44)
mean => 22.5
SD = 15.4
SD/√30 = 2.81
k factor for (DF = 30 – 1) @ 97.5% = 2.05
2.81*2.05 = 5.76
Stated answer => 23 ± 6
(1,2,3,4,5,6,8,9,10,11,12,14,15,30,31,32,33,34,35,36,38,39,40,41,43,44) {missing 7, 13, 37, 42}
mean = 22.15
SD = 15.4
SD/√26 =3.02
k factor for (DF = 26 – 1) @ 97.5% = 2.06
3.02*2.06 = 6.22
Stated answer => 22 ± 6
Please note that I have carried extra digits solely for the purpose of reducing rounding errors. The final answer follows Significant Digit rules.
I have also included a portion of Dr. John Taylors book as an image. It basically says the same thing concerning the digits in an uncertainty quote. There are many sites that say the same thing about physical measurements and their uncertainty.
Since SD is an indication of uncertainty, your values would all round to a similar number. Don’t be misled by those on here that use the SEM as a measure of uncertainty determined by dividing the SD by a number in the thousands. The uncertainty must tell one how accurately an actual physical measurement has been done and not how close a sample mean is to the population mean (SEM). An uncertainty far, far below the resolution of the actual measuring device is an indicator that one does not understand metrology or how physical measurements are made.
Following the NIST TN 1900 will not lead one astray when evaluating the expanded uncertainty of a sample of measurements.
“First Problem
How can one be sure that raw “unadjusted” numbers are really raw and unadjusted?”
You can’t, because they aren’t.
In the summer of 2009 I was going to compare the raw numbers with the homogenized numbers to see how much Hansen et al were creating warming. I downloaded all the raw charts from Iowa, Illinois, and Wisconsin. Then I got distracted for a few months, then I got started downloading some raw charts, then remembered I had already done that. Just to check, I compared newly downloaded with previous raw charts. They were different.
Bad luck for them. I accidentally caught them [doing something not good].
Here are my blink charts for the 3 states, all sites.
https://www.rockyhigh66.org/stuff/USHCN_revisions_wisconsin.htm
https://www.rockyhigh66.org/stuff/USHCN_revisions.htm
https://www.rockyhigh66.org/stuff/USHCN_revisions_iowa.htm
Those are not raw USHCN data. They are numbers as reprocessed by Gigtemp.
Sure they’re raw data. Both charts were labelled as raw data with nary a mention of Mr Gigtemp making them even better. Not long after these went viral (136,000 downloads international before I pulled off the counter), they had to relabel their artwork Version 2.
https://chiefio.wordpress.com/2010/01/15/ushcn-vs-ushcn-version-2-more-induced-warmth/
The labels on those charts are obviously not from GISS, but have been added for the blink.
Richard,
You can look at individual USCRN stations and compare the data with other weather stations nearby. I have for my area, and there is a huge difference between official measurements taken at the airport or at a NWS office and the USCRN station. I mean HUGE difference.
“Nearby” is meaningless. Just a few miles can make a major difference. Averaging all this stuff into a single number is just plain nuts.
Yep!
You use the data you have or you don’t use it at all. You don’t just create data because it makes the data distribution look more accurate. That is a statistician’s trick, not a physical scientist’s trick.
Richard Green said: “I do trust Roy Spencer and John Christy for UAH data”
Year / Version / Effect / Description / Citation
Adjustment 1: 1992 : A : unknown effect : simple bias correction : Spencer & Christy 1992
Adjustment 2: 1994 : B : -0.03 C/decade : linear diurnal drift : Christy et al. 1995
Adjustment 3: 1997 : C : +0.03 C/decade : removal of residual annual cycle related to hot target variations : Christy et al. 1998
Adjustment 4: 1998 : D : +0.10 C/decade : orbital decay : Christy et al. 2000
Adjustment 5: 1998 : D : -0.07 C/decade : removal of dependence on time variations of hot target temperature : Christy et al. 2000
Adjustment 6: 2003 : 5.0 : +0.008 C/decade : non-linear diurnal drift : Christy et al. 2003
Adjustment 7: 2004 : 5.1 : -0.004 C/decade : data criteria acceptance : Karl et al. 2006
Adjustment 8: 2005 : 5.2 : +0.035 C/decade : diurnal drift : Spencer et al. 2006
Adjustment 9: 2017 : 6.0 : -0.03 C/decade : new method : Spencer et al. 2017 [open]
That is 0.307 C/decade worth of adjustments with a net of +0.039 C/decade and that does not include the unknown magnitude of adjustments in the inaugural version A.
Pay particular attention to their infilling strategy.
15 grids representing 2.5° of longitude each at the equator is 4175 km. Compare this to GISTEMP which only interpolates to a maximum of 1200 km. GISTEMP does not perform any temporal interpolation.
My point is this. An awful lot of people put their full faith in 2 guys who perform some of the most (if not the most) aggressive homogenization, adjustment, and infilling procedures of any global average temperature dataset yet believe that everyone else is a liar and a fraud who is participating in a grand conspiracy to fake temperature data. Strange isn’t it?
I don’t pay attention to anyone who creates a global average. It’s complete nonsense.
It is either the man, the method or the machine. In this case I am inclined to think that it might be more machine related. I don’t know how they calibrate the probes. No doubt they are being attacked by the most energetic SW.
All UAH revisions are clearly documented, so even you can tell us what was done.
No financial incentive for Christy and Spencer to exaggerate global warming. their work done voluntarily without payment.
Those facts are all important to me.
“An awful lot of people put their full faith in 2 guys who perform some of the most (if not the most) aggressive homogenization, adjustment, and infilling procedures of any global average temperature dataset yet believe that everyone else is a liar and a fraud who is participating in a grand conspiracy to fake temperature data. Strange isn’t it?”
I believe the satellite methodology has the POTENTIAL for a reasonably accurate global average, mainly because of much less infilling than surface averages. Also, I have more trust in two private sector scientists with NO government funding, over government bureaucrat scientists, especially after the past few years of consistent government lying and censorship, such as lying and censorship about January 6, Covid and Covid vaccines, is a fool. Based on your comment, you are such a fool.
In the long run, the historical temperature trend does not matter much, as long as it is increasing, as it was from 1975 to 2015.
Because the predictions of FUTURE global warming are barely related to any past trend of global warming, even the cherry picked 1975 to 2015 period.
It’s not like manmade CO2 emissions began in 1975 and ended in 2015. CO2 emissions were mainly in the past 82 years, from 1940 to 2023, But the global cooling from 1940 to 1975 is usually ignored, especially after being “revised away”. And the flat temperature trend since 2015 gets no mass media attention.
UAH is *not* a global average temperature. I suspect Christy and Spencer will tell you the same thing if actually pinned down. It is a “METRIC”. It’s like measuring snow depth with an uncalibrated stick. You can tell if the snow depth is going up, down, or sideways by putting marks on the stick but you don’t really know what the actual depth values are.
Tim Gorman March 12, 2023 6:22 am
Not true at all, Tim. The UAH MSU is calibrated and validated against radiosonde balloon data, as well as reanalysis results. See Dr. Roy on the subject here.
Regards,
w.
WE said: “See Dr. Roy on the subject here.”
Keep in mind that the [Christy et al. 2018] methodology does two interesting things.
First…they use IGRA. Note what IGRA says about their own dataset.
Second…they adjust IGRA to match the satellite data.
WE said: “The UAH MSU is calibrated and validated against radiosonde balloon data”
It is true that UAH is calibrated and validated against radiosonde data to some extent. In fact, they use the data to bias correct satellite observations. But the context here is of spot measurements only. [Spencer et al. 1990]
Here is the comparison with 3 radiosonde datasets in terms of the trend.
It is *still* just a sample from a huge population and there is no guarantee that each orbit’s readings are the same distribution as the population. Different locations and different times for each measurement. It is no more capable of determining a “true value” for the globe than anything else. It is a *metric” just like using a stick to measure snow depth. That stick *will* tell you if the snow depth has gone up, down, or sideways but it simply can’t give you a “true value” for the snow depth. It really can’t even tell you *why* the snow depth changed, just that it did. Same with UAH.
“All UAH revisions are clearly documented, so even you can tell us what was done.”
That’s right. Nobody associated with the UAH satellite data is trying to hide anything. It’s all out in the open for everyone to see.
TA said: “That’s right. Nobody associated with the UAH satellite data is trying to hide anything.”
Except of course the source code and materials required to replicate their work.
RG said: “All UAH revisions are clearly documented, so even you can tell us what was done.”
They publish their methods in academic journals like all the others, but that’s it. They do not publish the source code and materials to replicate their work. Contrast this with GISS which publishes everything you need to replicate their work in as little 30 minutes.
“No financial incentive for Christy and Spencer to exaggerate global warming. their work done voluntarily without payment.”
I don’t think that’s true. According to their report
https://www.nsstc.uah.edu/climate/2023/february/GTR_202302FEB_1.pdf
But, regardless, the logic that voluntary workers are less likely to “manipulate” data than paid workers, is questionable. The usual argument is that all these producers of data sets are manipulating them in order to prove a point, not because they are being paid to do it. If money is the only motivation, it would be easy for other companies to offer more money to get the results they want.
“My point is this. An awful lot of people put their full faith in 2 guys who perform some of the most (if not the most) aggressive homogenization, adjustment, and infilling procedures of any global average temperature dataset yet believe that everyone else is a liar and a fraud who is participating in a grand conspiracy to fake temperature data. Strange isn’t it?”
Not really. The Weather Balloon data correlates with the UAH data about 97 percent, so those two guys must be doing something right.
TA said: “The Weather Balloon data correlates with the UAH data about 97 percent”
Sure. It correlates pretty well when you adjust radiosonde data, which the creators warn against using for climatic research, to match the satellite data like what [Christy et al. 2018] did.
Here is a comparison with three radiosonde datasets without adjusting first. Notice that the match isn’t so great.
“Fourth Problem:
There are many estimates included in the so called raw numbers, called infilling. Tony Heller, at his website, claims the estimated (infilled) data are a large percentage of USHCN data.”
Again, total confusion here. Raw data does not undergo spatial infilling. Heller is calculating the percentage of adjusted stations that have been infilled, basically because they were missing data.
But, absurdly, Heller has never acknowledged that NOAA replaced USHCN with nClimDiv in March 2014. Since than they have never posted a NOAA-calculated USHCN average for the USA. Heller’s simple solution was to calculate it himself, badly, and then castigate NOAA. So when, in the post you linked he posts this graph (my red), well, you can see the problem:
USHCN kept a fixed set of stations since it began in 1987. They were mostly staffed by volunteers, and over time, fewer were reporting. The fixed set was a good idea while it lasted, but by 2014 the dropouts had reached a level where they needed something new. But Heller kept going.
The percentage were already high BEFORE nClimDiv
Yes, maybe the change was overdue. But it happened.
“For example, the mid-1930s included the hottest US year for a long time. Hotter than the initial 1998 number. Then there were arbitrary adjustments and 1998 became warmer than any year in the 1930s. It that arbitrary adjustment also included in raw “unadjusted” data?”
Yes, at one time, James Hansen said 1934 was 0.5C warmer than 1998, and he showed this U.S. temperature chart as verification.
Hansen 1999:
Then when the temperatures failed to continue to get warmer after 1998, while CO2 amounts in the atmospher continued to climb, Hansen apparently felt the need to adjust the U.S. temperature profile so that 1934 was no longer warmer than 1998. If 1934 was warmer than 1998, then that would mean that the temperatures have been cooling since 1934, not climbing, and Hansen and the other climate change alarmists did not want that to be the case so they bastardized the temperature chart to promote 1998 and demote 1934.
And about temperature databases, somewhere in the Climategate emails is a note from a colleague of James Hansen where the author (I forget his name) told Hansen that the author’s independent data verfied that 1934 was 0.5C warmer than 1998.
Now that Hansen has bastardized his temperature record, and no longer shows 1934 to be warmer than 1998, I wonder what his colleague, who did show 1934 as warmer, thinks of Hansen’s changing of the temperature record?
Any temperature chart you see today that does not show the Early Twentieth Century as being just as warm as today is Science Fiction. The raw, unmodified data does not supprt any other temperature profile.
No comments from the Peanut Gallery?
Fig. 6 is a BIG problem for AGW alarmists. Not only is there no observational cause for alarm, there is no observational evidence for AGW. AGW was always long on theory (models) and short on observational support. AGW ignores natural variation (assuming A) to its peril.
We know models are wrong in several basic ways. All but one in CMIP6 produce a tropical troposphere hotspot that does not observationally exist. All but two produce an ECS significantly higher than observational energy budget methods, by about a factor of 2x. Sea level rise did not accelerate as modeled. Despite theoretical polar amplification, summer Arctic sea ice did not disappear as modeled.
Fig. 6 is a BIG problem for AGW alarmists. Not only is there no observational cause for alarm, there is no observational evidence for AGW
False
The effect of greenhouse warming should mainly be seen in the TMIN numbers, rising faster than the TMAX numbers, and that is exactly what is shown on figure 3 and figure 6.
The average temperature is the net result of ALL local, regional and global causes of climate change.
The average temperature does not have to match the expected warming pattern of increased CO2. But it happens to match in the US in the two charts above.
.
Greenhouse warming is EXPECTED to be mainly TMIN in the six coldest months of the year.
That is not how it is portrayed by the mass hysteria media though is it. We tirelessly keep hearing about heatwaves and record daily temperatures being the hottest ever. But Willis clearly shows that’s all bullshit.
It was so hot in Australia yesterday that a woman whose range was broken had her bald husband stand outside in the noon sun for a half hour. When his scalp warmed up enough, she fried an egg on his head. It was in all the Australian newspapers.
LOL. He obviously was not a Tasmanian, who reputedly have pointed heads.
Say what? You bust an egg on a guy’s bald head and it immediately runs off onto his shoulders and the pavement. Urban legend.
w.
W
I think it was a joke.
TFN
Poe’s Law strikes again …
w.
Istvan: Fig. 6 is a BIG problem for AGW alarmists. Not only is there no observational cause for alarm, there is no observational evidence for AGW
Greene: False
The effect of greenhouse warming should mainly be seen in the TMIN numbers, rising faster than the TMAX numbers, and that is exactly what is shown on figure 3 and figure 6.
At least part of what Rud said is true. There is no observational cause for alarm.
Nor is Tmin going up any kind of confirmation of AGW. Tmin could be going up for any number of reasons. AGW could be a “part” of it or none of it. The models certainly can’t distinguish.
“Nor is Tmin going up any kind of confirmation of AGW. Tmin could be going up for any number of reasons. AGW could be a “part” of it or none of it. The models certainly can’t distinguish.”
Good point.
“Greenhouse warming is EXPECTED to be mainly TMIN in the six coldest months of the year.”
So how much does CO2 increase TMIN?
Answer: Nobody knows.
Thanks for the very interesting look at the raw data and the fascinating maps indicating the warming and cooling of the maxima and minima. What struck me at first glance was how the coastal stations appeared to show far more warming than cooling. (more red dots than white). Any guesses as to why?
It might also be interesting if Willis could produce similar histograms using only those stations for which data is available for more than 30, or even 40 years, to see if they generate similar trends.
The oceans and deep lakes in the Northern Hemisphere are warming and retain their heat through winter. Winter heat advection from ocean to land is increasing. So the regions most influenced by the oceans (and large lakes) is warming the most.
A consequence of the increased winter advection is increasing snowfall. Snowfall records will be a feature of weather reporting for the next 9000 years. The warming of the NH oceans has only been occurring for about 500 years.
The single place and time that shows the most warming on the entire globe is the Greenland plateau in January. It has warmed from -30C to -20C in the past 70 years.
As an oceanside resident in the mid-Atlantic region, I notice that the ocean has a moderating effect on whatever temperature exists as little as a mile inland, making my residence cooler in the summer and warmer in the winter than those living more inland.
I watch the artic air as it circles the globe and I have noticed that when it starts getting close to the UK the ocean starts moderating the temperatures and the UK barely gets touched by the cold air because it has warmed by the time it gets there.
Population density is growing more in the coastal regions causing more UHI?
That struck me too. My first guess would be warming surface water.
The eastern half of the country seems to be cooling and the western half warming
I hope the left coasters don’t move East
They already have been.
“In my youth, I spent a couple of winter nights sleeping on a piece of cardboard on the street in New York, with newspapers wrapped around my legs under my pants for warmth.”
I can empathize.
The coldest life of my youth was spent trekking up the Baltoro glacier on a shoestring budget of food and equipment.
Trying to sleep, having placed every piece of clothing, fabric and equipment, except the ice axe, underneath, the ground still sucked heat out of my body.
It was only later that I realised that pitching the tent on flat stone was much worse than pitching it on snow/ice.
The coldest I have ever felt (including after years of racing sled dogs in Alaska) was during the monsoon season laying in rice paddy mud for night ambush operations in Vietnam. Just thinking about those nights makes my bones hurt.
It could get chilly over there. Monsoon, rain, mud, cold.
I was there in 1969 when Vietnam got hit by a Typhoon and dropped 22 inches of rain in 24 hours. I don’t remember the name of the Typhoon.
I was in a bunker located about 50 feet from a 50-foot-wide-creek and within a matter of hours after it started raining, we had to move to higher ground as that creek turned into a roaring river.
Where were you located, Tom?
I was living right next to a bridge at the east end of the An Khe pass, at the time. Four Americans and 40 South Korean infantry who were guarding the bridge.
My war was different: As part of the 9th Division, we were dealing with daily tides during combat patrols, helicopter assaults and ambush operations in the Mekong Delta.
I forgot to add, I was wounded on a night riverine operation in a converted LST.
Just an old extreme camper. Used to snowshoe up big NE mountains in mInus 20 F weather. So, to keep warm,
I thrived in a two pole simple V tarp shelter (not a tent) at 20 below when that night before the wood reflector fire, had my hot coffee freeze half thru the old army issue canteen cup aluminum mug. Now, admittedly used the snow shoes to dig out a snow bank place below the wind, roofed with cut fresh evergreen boughs, just in case it began snowing heavily again before setting up my four corner tarp
You used the space blanket upside down.
Some home/house insulation products come with ‘shiny sides’ = always a layer of Aluminium foil. Of course **everyone** thinks that the shiny stuff is ‘reflecting heat’
Wrong. The shiny/reflective bit is simply a feature of the material
If you read the instructions that come with those shiny insulation products (the ones that know their job and what they’re talking about) – they will say to install the material with the “Shiny side facing the cold”
Not because the shiny side reflects the ‘cold from getting in’
It is that Aluminium has very low Emissivity
Other shiny substances would not work.
It is why Thermos Flasks haven’t just got a vacuum inside them, but also the shiny Aluminium layer. The vacuum stops conduction and convection while the Aluminium stops radiation.
I have explained this A Trillion Times on here – yet Magical Thinking stops the message getting through every single time.
So the SpaceBlanket works by
Trapping warm air (stopping convection)When that warm air (object inside the blanket) warms the Aluminium foil layer, the Aluminium does not radiate the heat away (to the extent most other materials would)The foil does not reflect the heat back in – it stops it from getting out. Those are NOT the same things, like the difference between a Tax Credit and a Subsidy
That last point is vital when considering the GHGE and The 2nd Law is properly applied
i.e. When energy has radiated away from any object, it instantly at that time becomes ‘spent energy’ or ‘waste heat’
iow: It has started its path down a thermal gradient
The 2nd Law, Entropy, Carnot. Stefan/Boltzmann and everyday experience tell me. you, anyone that that energy can NOT return to the object that radiated it away
The GHGE as always explained is total junk.
The only way Earth can get warmer in the presence of a Constant Sun is if either its Albedo and or its Emissivity reduced
It does not matter what Earth is made of – apart from the Emissivity value of whatever that substance is.
Whatever is absorbed and re-radiated inside Earth is utterly irrelevant.
Emission, absorption and re-radiation are no different than Conduction and the GHGE is not (supposedly) a conduction effect
As it happens and at the temps/pressures of Earth’s atmosphere, CO2 does actually have vanishingly low Emissivity.
But at the concentrations it is at in the atmosphere, the effect will be unmeasurable.
“The 2nd Law, Entropy, Carnot. Stefan/Boltzmann and everyday experience tell me. you, anyone that that energy can NOT return to the object that radiated it away
The GHGE as always explained is total junk.”
That is not true. The 2nd law only requires that the radiated energy from the hot object to the cold object be greater than the radiated energy from the cold object to the hot object. The net flow of energy is from the hot to the cold.
The GHGE lives.
I took a thermodynamics class in the 1970s. It was awful but I passed. I can not understand why so many conservatives pontificate about thermodynamics, which they do not understand, and then use their misinformation to declare there is no greenhouse effect. Which leads to the claim that CO2 does absolutely nothing.
The military emergency “space blankets” issued when I was in, and which we all carried in our “bug out kits”, were shiny on one side and OD green on the other. The obvious intent being that the OD be facing out.
Peta, your “The shiny/reflective bit is simply a feature of the material” is not even wrong: The actual radiative science (in practical use since the 1970s) is “The reflective agent on space blankets — usually silver or gold — reflects about 80 percent of our body heat back to us.” [from “How Stuff Works”] It was originally built to reflect sunlight from the space station to keep from overheating. It is used worldwide to reflect body heat back to the person it covers in all sorts of medical and inclement weather uses.
BTW, the shiny side of standard fiberglass batting insulation placed between the studs and rafters faces inward to act as a vapor barrier. It also holds the batting together for ease of transportation and use. When was the last time you built a house?
Thanks, Willis!
Those links to the USHCN sources appear not to be the latest available though. The daily data appears to be through 2015.
I have been using the following links to access both the daily and monthly USHCN files which NOAA keeps up to date.
Daily – these are not adjusted. Each station file contains its entire record.
At this link: https://www1.ncdc.noaa.gov/pub/data/ghcn/daily/
The ghcnd_hcn.tar.gz file contains all the 1,218 USHCN station files of daily data.
Or the individual files can be found here. https://www1.ncdc.noaa.gov/pub/data/ghcn/daily/hcn/
And the monthly files are here.
https://www.ncei.noaa.gov/pub/data/ushcn/v2.5/
The monthly files by station are separate for “raw”, “tob” (time of observation adjusted) and “FLs.52j” (after pairwise homogenization) tmax, tmin, tavg. And raw and FLs.52j for precip.
Finally, about the adjustments. Your comment is, “This also makes it very hard to estimate the effect of the adjustments.” Yes, but the USHCN monthly files can be analyzed by station and in aggregate to directly see the effect over time of the tob and FLs.52j adjustments as applied to a particular month’s raw values. At this link are plots for the monthly tavg values for December, from 1895 through 2021, for the mean of all USHCN stations reporting a value.
https://www.dropbox.com/sh/23ao8mh3b4j4rpg/AAB6Gx5DEtOrHEEfKXcVaF5ba?dl=0
Again, much appreciation for this post and for all your work.
Thanks, David. You are correct that the data I used only runs to the end of 2014. Your links to more current data are appreciated, I’ll take a look when I have time.
Best to you and yours,
w.
Heat transport and storage dynamics have almost nothing to do with radiation in the turbulent boundary layer.
It’s all about tangible heat, net latent flux, and material properties (specific heat or volumetric heat capacity). These are very local factors, subject to very localized variability.
This is most evident at night using near surface thermometers.
Note that net latent flux (QE here) is up and out of the turbulent boundary layer. The magnitude of the upward daytime arrow is larger than the nighttime downward arrow. The heat released in cloud condensation aloft exceeds the heat released in condensation of ground dew and frost.
QH does not have such behavior (sensible heat).
a better illustration
According to the US National Institute of Standards and Technology: “To measure the temperature, thermometers have historically used the fact that liquids such as mercury and alcohol expand when heated. These thermometers are reasonably accurate, to within a degree or two” (How Do You Measure Air Temperature Accurately).
+/-1C or +/-1F seems the most accurate and precise that can be assumed from the historical record given even the most diligent observers.
I’m not sure in the case of weather stations the large number of measurements and so-called ‘adjustments’ improve the data quality to narrow the confidence level from +/-1 (C, F).
They don’t. Those are the uncertainty intervals of each individual measurement. Averaging different things, i.e., one time readings of a passing temperature provides no distribution that can be used to lower the uncertainty of individual readings.
In addition, the biggest part of the uncertainty interval has to do with the resolution (precision) of an LIG or MMTS station. If the temperature is recorded in integer fashion, averaging integers can not and does not increase the resolution available. Adding decimal digits by averaging is functionally creating new information out of thin air. It is why significant digit rules were created. Those rules prevent altering the resolution of the original measurements.
±1 C is good estimate for the uncertainty of older observations. Observations using modern instrumentation are probably closer to ±0.5 C. So for a monthly average at a station the uncertainty would be about 1/sqrt(60) = 0.13 C and 0.5/sqrt(60) = 0.06 C respectively for the uncorrelated case [JCGM 100:2008]. Adjustments only remove error arising from systematic effects. They do not do anything to improve the uncertainty arising from random effects.
You confuse variation of the stated values of the data with the measurement uncertainty of the data.. x/sqrt(y) is the SEM. It’s a measure of the variation in the measurement values. It’s how closely your estimate of the average approaches the population average. The measurement uncertainty is totally different. If the population average is not accurate the uncertainty simply can *not* be less than the uncertainty of the measurements. It usually would be the root-sum-square of the individual measurements and certainly no smaller than the inherent uncertainty of the individual measurements, i.e. +/- 0.5C.
+/- 1 and +/- 0.5 are *NOT* the variation in the measurement data. They are not appropriate measures to use in deciding how close you are to the population average.
If your ruler is off by an inch then it doesn’t matter how many measurements you take, the average will be off by an inch. No amount of averaging can lessen that. You can take all samples you want, it won’t help.
+/- 1.0 and +/- 0.5 are measurement uncertainty and have two components, random error and systematic bias (the ruler being off by an inch). You simply have no idea of the size of each component which means you can’t just ignore the measurement uncertainty. And, once again, the SEM is *not* measurement uncertainty.
If you would include these words in every post you make on the subject maybe it would sink in. “Variation in the stated values of the measurements is not the measurement uncertainty”.
“If your ruler is off by an inch”
Ah, the usual conflation of random and systemic error. Yes, if you have an unknown, constant, systemic error in every one of kazillions of temp measurements over the decades, then the temp trend would be – oops – unaffected. But what you are (perhaps unintentionally, due to your Dan Kahan System 2 bias), claiming is even more unlikely. You are claiming that when these systemic errors start, they are increasing temps by large fractions of a degC, and then, as the decades go by, those errors are smoothly reduced to nada, and finally, are then smoothly replaced by errors that decrease that apparent temp, also by large fractions of a degC. All with nada for technical backup. Sorry Maxwell Smart – I find that hard to believe…
blob the clown weighs in with a hand-waved blob word salad.
Seriously, karlo? Your answer to a reasoned argument is that garbage insult without a scrap of actual refutation?
Read this before you embarrass yourself by posting again.
w.
Willis,
km is correct. bigoilbob just threw out a word salad with no actual refutation contained in it.
b-b won’t accept that a measurement of 2.5C +/- 0.5C and a second measurement of 2.6C +/- 0.5C doesn’t automatically mean a positive trend.
Like so many in climate science he always wants to ignore that +/- 0.5C uncertainty.
In TN1900, Possolo made two very restrictive assumptions in order to allow the variation of a partial set of Tmax values from the same station to define the uncertainty of the monthly average Tmax. The first assumption is that there is no systematic bias in the measurements. The second assumption is that the measurement uncertainty is random, Gaussian and therefore cancels. Therefore the measurements of the temps become the stated values only.
That is what b-b *always* uses as unstated assumptions. If you don’t use these assumptions then you can’t claim that the stated values define a specific trend because you *can’t* know that due to the measurement uncertainties.
You could also just ban me for my bad attitude toward the trendologists instead of going for the mime.
And it is quite pointless trying to argue with these persons, but go ahead, have fun.
“Yes, if you have an unknown, constant, systemic error in every one of kazillions of temp measurements over the decades, then the temp trend would be – oops – unaffected. “
Malarky!
“You are claiming that when these systemic errors start, they are increasing temps by large fractions of a degC”
I’m claiming no such thing! Stop putting words in my mouth. You do *NOT* understand measurement uncertainty at all! The *actual* value of the measurement done in the field is always unknown, every single time. You can’t tell if the temps are increasing or decreasing or are stagnant as long as they remain within the uncertainty interval.
How do you know that 2.5C +/- 0.5C and 2.6C +/- 0.5C define a positive trend?
The stated values certainly do if the uncertainty is ignored as you want to do.
The first temp can range from 2C to 3C. The second temp can range from 2.1C to 3.1C. 3C for the first measurement to 2.1C for the second defines a NEGATIVE trend. How do you know that isn’t the actual trend?
The problem is that Tmax and Tmin are highly correlated. A simple arithmetic mean of the two values is not a transform that can remove that correlation. When you start with correlated data the data IS NOT independent and it stays that way regardless of how much you average it. Your use of 60 data points for the SEM indicates that you are using correlated data.
This is one reason that that Tmax and in should be evaluated separately.
Correlated data invalidates any statistical calculation requiring independent values such as your reduction in “error”. Neither the Law of Large Numbers nor the Central Limit Theory can be used in the fashion you are doing when data is correlated.
Lastly you are calculating the SEM which defines how well the sample mean represents the population mean. It is not a measurement uncertainty that is propagated. Nor is it a proper use of significant digit rules. You can not declare a calculation to have more resolution than what the original measurement contained.
Following NIST TN 1900 Example 2, one should divide the the SD of the sample by the number of data points then expand that value to a 95% confidence level. You will find that far exceeds the values you are arriving at. That is one reason that NIST declared measurement uncertainty as negligible.
Of relevance to this article are the following publications.
Vose et al. 2003
Hubbard & Lin 2006
Menne & Williams 2009
Hausfather et al. 2016
Note that nClimDiv supersedes USHCN. USHCN is considered a legacy product, but is still updated daily and made available to the public for historical purposes. The data files can be found here. The PHA source code is available here.
The way to measure how much the adjustments matter is to download the FLs.52j and raw files. You’ll have to roll your own gridding, infilling, and averaging code though. You could do a simpler non-grid analysis, but that comes at the cost of overweighting urban areas.
That is for version 2. Version 2.5 uses PHA.
That’s fine, but your analysis will be contaminated with the time-of-observation change bias, station relocation bias, station commissioning/decommissioning bias, instrument/shelter change bias, etc. The biases known have the largest impact are discussed in [Vose et al. 2003] and [Hubbard & Lin 2006]. Make sure you cross reference the citations. For example the TOB bias was known back in the late 1800’s with a long history of discussion and strategies for mitigating appearing in the literature.
Validating PHA can be done in a variety of ways. See [Menne & Williams 2009] [Williams et al. 2012] [Venema et al. 2012] and [Hausfather et al. 2016] for details. The Hausther et al. 2016 approach is compelling because it uses the overlap period with the USCRN network.
‘The Hausther et al. 2016 approach is compelling because it uses the overlap period with the USCRN network.’
I bet it is ‘compelling’, given that the goal seems to be to use homogenization to pollute data from relatively pristine rural stations with data from urban stations that has been hopelessly corrupted by UHI effects.
At the end of the day, the only way to infer any change in climate from temperature records is to look at individual t_min and t_max records from rural stations, wherein any change in location, instrument, methodology, etc., means that the old record has ended and a new record has begun. Only this allows one to say if temperature for a specific location during a specific period has gone up, down or stayed the same.
While this certainly puts a damper on calculating the Earth’s surface temperature from ‘pre-industrial’ times, the simple truth is we just don’t have the data and tampering with the sparse data we do have is simply dishonest.
USCRN is not homogenized or adjusted. It does not “pollute data from relatively pristine rural stations with data from urban stations” or is “hopelessly corrupted by UHI effects.”
That’s great! Hopefully in 30 years, or so, we’ll have sufficient data to infer individual temperature trends at each of these supposedly pristine locations.
No such thing as “relatively pristine rural stations”. As Dr Spencer has clearly shown, all areas in the US have been growing.
Wind, inversions, pressure fronts (related to wind), and land use can all spread UHI over vast areas – even to the supposedly “relative pristine rural stations”.
“You’ll have to roll your own gridding, infilling, and averaging code though.”
And that’s where it all goes wrong. Averaging alone, of disparate stations, is a major no-no. And infilling, is just making shit up.
Infilling and averaging only serve to falsely make the data distribution more peaked around the average than it truly is. It makes the standard deviation of the distribution artificially smaller.
If you have 1000 measurements with a standard deviation of σ1 and you add 1000 more data points equal to the average of the original 1000 measurements, what does σ2 become?
Tim Gorman March 13, 2023 4:12 am
Um … er … since that’s not in the slightest what I’m doing, so freakin’ what? It’s like saying:
Doesn’t matter. I’m not doing that either, or anything like that.
w.
The operative words are “Averaging alone, of disparate stations“
If you are adding data points that you have *not* measured then you are screwing around with the distribution. If the data you have is not fit for purpose then adding “guesses” in order to create more data points won’t help. It just hides the problems the data has.
Finally realised the relevance of looking at temperature range rather than anomally.
Anomalies remove most of the information in a data set as you have now discovered.
Averaging removes even more data since it hides the actual variance of the temperature profile. You can have two different locations with the exact same “average” but widely different temperature profiles with different variances – meaning different climates. Creating other averages with those original averages just hides even more of the variance. Every time you do an average you lose data.
I seem to recall the BEST temperature dataset showed the same thing; most stations showed ‘global warming’ but 20% or so did not. “Clearly, “global” warming isn’t.”
BEST is Science Fiction, too.
Any temperature chart that does not show the Early Twentieth Century as being just as warm as today, is Science Fiction. Best does not show the Early Twentieth Century are being just as warm as today, therefore. . .
Excellent Willis. Raw data with explanations of which sites might be compromised due to poor siting or urban growth is far more meaningful and believable than data that has been adjusted for whatever reason. Even with the problems we know exist I don’t see anything to be concerned about. Yet more proof that we are being lied to and cheated by those we should be able to trust.
I’m not a fan of average (mean) temperatures and even less so of mid-range values. However, I don’t think that your claim can be logically supported. If someone stays in the same location where they experienced the daily low, they will also experience the mid-range value as the day heats up.
Clyde, it seems my meaning wasn’t clear. We can tell when the day is at the hottest and the coldest. Either we can sense it directly, or we can hold a thermometer in our hands for 24 hours.
But even with the thermometer in our hands, we can’t know when we hit the “average” temperature. This is particularly true when the “average” really isn’t a true average, it’s just (MAX + MIN)/2. It’s not a real phenomenon, like the hottest temperature. It’s a mathematical construct.
w.
Even with the advantage of a thermometer in hand, one cannot know that they have ‘experienced’ the daily max or min until some time after it has passed. Without a thermometer, I doubt that most people can properly estimate the temperature to +/- 5 deg C except at the freezing point. While someone may not know when the daily mid-range temperature occurred, they will have ‘experienced’ it.
Let me try a metaphor. It’s like walking on a trail that has hills and valleys. You can know when you’re at the bottom or the top. But you don’t know when you’re at the average height.
Or to take a different tack regarding temperatures, a day that goes from -10°C to 20°C in 24 hours is very different from a day that goes from 4°C to 6°C in 24 hours … but both have exactly the same average temperature.
Which is my point. Highs and lows are actual observations. The average is a mathematical construct.
w.
But that problem exists for Tmin and Tmax as well. Neither Tmin nor Tmax are the instantaneous low and high values for the day. They aren’t even instantaneous values. They are themselves averages albeit over a short period of time. That means people don’t experience those either.
I get it! Since thermometers don’t provide instantaneous readouts, we shouldn’t have an issue with averaging T_min and T_max, which I guess also means we shouldn’t have an issue with grafting modern temperature records on to bristlecone tree ring reconstructions if that helps the rubes come to the right conclusions.
TMIN and TMAX would change from changes in measurement instruments. It would be possible now to have a TMIN or TMAX for a 5 second period during a day. I bet the older equipment could not do that.
See my response to bdgwx above.
w.
It is possible for a modern instrument to have response time of 5 seconds. They just aren’t typically deployed to ASOS stations. And you correct, LiGs cannot respond as fast modern instrumentation.
Dunno about today, but for most of the period of record mercury min/max thermometers were used, like the one we had at our house in the fifties. And yes, they do measure the “instantaneous low and high values for the day”.
Here are typical specs, in this case for the unit in the above photo:
Used to be my job as a kid to use the magnet to reset the floats for the next day’s recording.
w.
Is it possible for modern equipment to record the warmest and coldest ONE SECOND of a day?
Would the older thermometers have the ability to respond that fast, with the same level of precision? I doubt it.
I am thinking about a jet plane moving past a thermometer at an airport, with the heat from the jet engine exhaust hitting the thermometer for a moment.
Even the sensors used today have thermal inertia. They simply can’t respond instantaneously. Are they faster than LIG devices? Probably. How much faster actually depends on the entire measurement device, not just on the sensor itself.
The air moving through the measurement device will be conditioned in some manner by the entire device. If the material in the device’s airflow is cooler or hotter than the air, the temperature of the air will be changed in some manner. How much depends on several factors including changes in the air flow due to obstructions such as dirt and other things, e.g. snow or ice blocking the inlet.
It’s why measurement uncertainty in the readings is such an important consideration. But climate science never seems to understand that simple fact.
LiGs are not instantaneous either. [Burt & Podesta 2020]
“And yes, they do measure the “instantaneous low and high values for the day”.”
Respectfully, they simply can’t. The fluid in the thermometers have thermal inertia. Meaning they can’t respond instantaneously. If the temperature peaks in value and then starts to fall before the fluid can respond. The fluid will never catch the actual instantaneous peak. It will stop responding when the falling temperature matches where the fluid temperature is at the time.
In reality it probably doesn’t matter very much. The measurement uncertainties associated with the instrument will be wider than the difference between the instantaneous peak and the actual reading of the fluid. It’s why the measurement uncertainty should be propagated throughout all of the temperature data bases and should be considered in any “average” reached using the temperatures – but for some reason in climate science measurement uncertainty is always ignored, it seems to always be assumed to be zero!
Tim Gorman March 13, 2023 4:24 am
Yes, I know that, Tim. However, I was talking about the practical reality. You know, the part where you say
Because (as you point out) it “doesn’t matter” I didn’t include the slight lag in instrument response.
How about you focus your interest on something that actually matters, rather than trying to score points by boring us with meaningless trivia?
w.
Willis,
It is *NOT* meaningless trivia. The thermal inertia *is* part of the measurement uncertainty. It doesn’t just apply at Tmax and Tmin but for all measured temperatures. It’s why in calibration lab processes using water baths the amount of time the temperature sensor has to remain in the bath is usually specified.
I know in climate science it is always assumed that measurement uncertainty is random, Gaussian, and cancels but that simply isn’t true in practice. It is *not* just noise. It can’t just be dismissed as meaningless.
Tim Gorman March 13, 2023 12:23 pm
First, you said:
“In reality [thermometer thermal lag] probably doesn’t matter very much. The measurement uncertainties associated with the instrument will be wider than the difference between the instantaneous peak and the actual reading of the fluid.”
Now, in some vain attempt to stand on tiptoes in order to bite my ankles, you say:
Pick a damn lane and stick to it. You’re contradicting yourself.
w.
Yes I used to operate my high school’s weather station for about 5 years, reset the floats every lunchtime.
Thermometers have hysteresis so that they do not respond instantaneously. It is one of the items that goes into the NOAA/NWS specs for uncertainty. If I remember correctly, LIG’s have something like a 30 second period before they can respond to a step change. If the temperature changes within that period, the LIG will never show the instantaneous maximum or minimum temperature.
The response time of an LIG is about 30 sec, this is the time it takes to reach 63% of the step change. If you know the response time it is possible to calculate what the actual temperature history was from the measured temperature trajectory.
Willis, Tmin and Tmax are themselves averages at least for modern digital instrumentation. For example Tmax = (T0+T10+T20+T30+T40+T50) / 6 and similarly for Tmin. The difference between Tmin/Tmax and Tavg is that the former averages 6 values whereas the later averages 12 values from two subsets of 6 values each. See the ASOS User Guide for more details.
You don’t mention the reason for this. It is so that temperatures can be adequately correlated with what an LIG thermometer would show. Otherwise, you could never compare readings from the two. All records would have to be stopped, which they should be anyway, immediately with the change.
If anyone is interested, here is a 2016 study (https://etda.libraries.psu.edu/catalog/13504jeb5249) that looked at 215 US airport stations to compare the differences between min-max averaging and hourly averaging (since the daily temperature curve is of course non-symmetrical). They found that the differences varied by season predictably, mostly due to six significant climate variables (cloud cover, precipitation, specific humidity, dew point temperature, snow cover, soil moisture). Generally, the max-min method “overestimates daily average temperature at 134 stations, underestimates it at 76 stations, and has no difference at only 5 stations.” The differences are greatest in summer (in August, the average difference for all 215 stations was +0.54F). They also found that the shape of the diurnal temperature curve changes over time (from 1980-2010), which is interesting, but maybe expected for airport stations. Here’s the (kriged) map of differences for August (1980-2010), it looks like the min-max method overestimates average temperature by about .5F for me in PHL.
w. ==> If the data you processed was”the raw, unhomogenized, unadjusted daily data files” — why is it also “CDIAC’s most current version of USHCN daily data.”?
If it has been recorded and remained unchanged, there would not be versions, of which this is the most current — versions mean it has not remained the same.
Anyone else notice this? Where, if anywhere, are the previous versions? Are they different? How different? Why different?
Once again Hansen is Mr. Smarty Pants here.
“most current version” suggests there were many prior versions
This is the best comment here today.
Here’s my theory:
If the raw data supported the coming climate crisis narrative, they would be available to the public without adjustments, revisions, infilling and versions. If there are versions, then there have been “adjustments”.
When raw data are adjusted, they are no longer data
They are an estimate of what the raw data would have been if measured correctly in the first place, or deliberate science fraud.
Kip, please see at this link under “methods” for NOAA’s GHCNd, of which the USHCN station daily data is a subset, for more information. The daily USHCN station data would have passed through quality checks as described there to be published. But not time-of-observation, pairwise homogenization, or other adjustments for station changes etc. (if I understand this correctly!)
https://www.ncei.noaa.gov/products/land-based-station/global-historical-climatology-network-daily
So yes, it is the case that these are the “the raw, unhomogenized, unadjusted daily data files.” It is also true that certain QA checks may have flagged or removed values that violate the tests.
Please also see my comment above about links to the currently maintained USHCN data (and for daily data, also for GHCNd).
David ==> “So yes, it is the case that these are the “the raw, unhomogenized, unadjusted daily data files.”
That is far from the case — the link clearly states the opposite. Stations are not even a set number of stations, they don’t necessarily include the same stations in each versions, and then some stations which are mingled with other stations.
I don’t think you have understood the magnitude of the process.
The “raw, unhomogenized, unadjusted daily data files.” would be just that — a predetermined set of stations, with their normal daily reported values, untouched by automatic or human corrections or changes. There must be, of course, some error checking — missing values, or “999s”….but these should be flagged.
It is possible to check the RAW data, many stations have this available day by day. Unhomogenized means specifically NOT MINGLED. And, of course, UNASDJUSTED mean that NO adjustments, no matter how seemingly totally justified.
The data set used by willis might be the best we have easily available — but it is NOT Raw, it is NOT UNHOMOGINIZED, and it is NOT UNADJUSTED.
Kip, I’m not going to get in a semantic debate on this. Just explaining. I believe I understood Willis’ use of those words when he wrote, “These appear to be the raw, unhomogenized, unadjusted daily data files.” I don’t think he is wrong. This means that there has been no time-of-observation adjustment or pairwise homogeneity adjustment applied to the daily values contained in the files. Quality processing and flagging has been applied, yes. But not the two key adjustment algorithms that are applied later as monthly values are computed for the legacy USHCN list of stations (and for taking GHCNd data into ClimDiv.)
The “version” issue does not bother me much, as a managed dataset might indeed have had differences in format, file structure, processing, etc. applied.
All the best to you.
I don’t think that looking at the entire available USHCN provides the whole story. The relationship between Tmax and Tmin has not been consistent.


https://wattsupwiththat.com/2015/08/11/an-analysis-of-best-data-for-the-question-is-earth-warming-or-cooling/
You might get very different results if you just looked at 1982 through 2022.
It is interesting to note that aerosols increased significantly post WWII. But then starting around 1980 aerosols began to decline. This could explain the more rapid decline in the diurnal range from 1950-1980 and an increase from 1980 to 2015. Note that an increase in aerosols suppresses Tmax more than Tmin while a decline augments Tmax more than Tmin since they modulate the solar input.
1975 to 1980 SO2 emissions rising but temperature is rising too, not falling, as would be expected with rising SO2 emissions
2015 to 2023 SO2 emissions falling, but the temperature trend was flat, not warming, as would be expected from fewer SO2 emissions.
Seems like SO2 is a minor cause of climate change.
“Seems like SO2 is a minor cause of climate change.”
No correlation.
Net-zero climate effect with a good chance of greening.
Willis, your map of the USA showing areas of increasing and decreasing maximum temperatures is interesting. Looking at California on the map, most of the UNHCN stations seem to have increasing maximums. I have looked at California stations with long temperature records but less urbanized areas, and found generally those stations have flat or decreasing maximums, with the exception of some in the desert southeast, and the central coast. The aggregate of 27 weather stations geographically spread over the state with best siting and long records (90 years or more) the maximum temperatures show an upward trend of about 0.7 F per century, and minimums have an upward trend of about 2.6 F per century. I think once urban heat island effect is controlled, the split between rising and falling maximum temperatures in California is close to even, while minimum temperatures have definitely increased statewide.
Probably the necessary data isn’t widely available but it seems to me that a different measure of trend would be more realistic. From some long ago reading I learned about the concept of what I think was called heat hours. This was mainly in relation to fruits, which I presumed included annuals such as tomatoes and peppers on the warm side while the cold side possibly only related to perennials such as trees (many fruits), shrubs (nuts and berries), and vines (berries).
Basically, some minimum hours of temperature above some particular temperature is needed for proper ripping and some minimum hours of cold below some particular temperature is needed during the dormant stage to assure the next year’s crop.
Some places I’ve lived frequently have temperatures still around 100̊F at midnight, meaning the “hours of heat” however they are defined, are rather numerous. However, some days with maximum at 110 and above were down to 70 well before midnight.
Where I am currently is not so cold as some places, but overnight lows were frequently around 20̊F. During this winter, my only experience so far, they were never below freezing during early afternoon but some days were close to freezing again by 4:30 PM.
My point is that min and max temperatures may well not reflect the “amount” of hot and cold very well so not be a very accurate measure of what the area is really like or whether or not any significant change is taking place.
The temperature profile during the day is approximately a sine wave. The path of the sun over a specific location is a sinusoid so this makes sense. The temperature profile at night is an exponential decay, which also makes sense.
What you are describing is called degree-days. You can have growing degree-days in agriculture, cooling or heating degree-days used for sizing HVAC requirements in a building, and even soil temperature degree-days.
Degree-days are a much better representation of climate, at least in my opinion. It’s why the ag sector and building engineering sector use degree-days. Both are *very* climate dependent.
The old method of calculating degree-days used the daily median values just like climate science does today. But 20 years ago or so industries moved to using integrals of the entire temperature profile to calculate degree-days. It provides much better estimates of the climate at a location. For some reason climate scientists have remained stuck in the 20th century. The big question is why.
I don’t know if night is the correct time for the decay to start. According to the graph, the decay in air temp starts around 4pm to 5pm.
There is heat storage both in the soil and in the atmosphere. This will have some hang over before the change really gets going.
I recall Roy Spenser examined CA temperatures a few years ago (6?) and related warmer night-time temperatures to irrigation being used on increasing acreage. Maybe that was reposted on WUWT but that I do not recall. It might be searchable. Not saying urban heat island effects do not contribute.
One for Willis to ponder.
On any given night at my simple little Accurite weather station the dew point and the temperatures will lock together and look as if the low temperature is being limited by the moisture in the air. The temperature drops until it hits the dew point and then they track together all night while dropping only a couple degrees C more. It’s hard for me to see how a daily low temperature measurement is meaningful without also knowing what the dew point is. Alternatively, what would the temperature be if it were a function of radiation only without being held up by heat released by water vapor changing to liquid state.
I just don’t see how this obvious phenomenon is being considered. Been wondering this for a while.
My location is in East Tennessee.
It’s why temperature is such a poor proxy for enthalpy which is what you are actually describing.
Willis,
Thank you for this – but – are the red dots actually different to the white dots or do their uncertainties mostly overlap?
Some modern statistics programs provide easy-to-use analysis of data for quality control, even forensic analysis that looks for dud stuff. The program JMP is an example.
With Tom Berger, I did some analysis of Australian data on WUWT late last year. It would be interesting to see similar work on US data and that on many other countries. I cannot understand its (supposed) absence in IPCC reports, for example.
In science and metrology, it really is basic, accepted procedure to understand the limitations of your numbers before you use them for serious purpose.
Our Australian work has showed parties unable to agree on how uncertainty should be measured, unable to accept that “RAW” data have been fiddled by unreported means and people and more. Read it here, the last link in particular.
The middle link had 839 comments, very large for WUWT, including regulars like bdgwx, nick stokes, bellman. Some are writing again on this Willis article as if they had never read the following, that is, they appear not to have learned from them.
Geoff S
https://wattsupwiththat.com/2022/08/24/uncertainty-estimates-for-routine-temperature-data-sets/
https://wattsupwiththat.com/2022/09/06/uncertainty-estimates-for-routine-temperature-data-sets-part-two/
https://wattsupwiththat.com/2022/10/14/uncertainty-of-measurement-of-routine-temperatures-part-iii/
“The middle link had 839 comments, very large for WUWT, including regulars like bdgwx, nick stokes, bellman. Some are writing again on this Willis article as if they had never read the following, that is, they appear not to have learned from them.”
Huh? I didn’t comment on any of those articles, and all I’ve asked in this one is for clarification on what time period is being used for all these trends.
Bellman,
My apologies. You did not post directly, but you were in my mind since bdgwx was mentioned with you a few times in the one sentence. Geoff S