From Dr. Roy Spencer’s Global Warming Blog
Roy W. Spencer, Ph. D.
I’ll get right to the results, which are pretty straightforward.
As seen in the accompanying plot, 50-year (1973-2022) summer (June/July/August) temperature trends for the contiguous 48 U.S. states from 36 CMIP-6 climate model experiments average nearly twice the warming rate as observed by the NOAA climate division dataset.
The 36 models are those catalogued at the KNMI Climate Explorer website, using Tas (surface air temperature), one member per model, for the ssp245 radiative forcing scenario. (The website says there are 40 models, but I found that four of the models have double entries). The surface temperature observations come from NOAA/NCEI.
The official NOAA observations produce a 50-year summer temperature trend of +0.26 C/decade for the U.S., while the model trends range from +0.28 to +0.71 C/decade.
As a check on the observations, I took the 18 UTC daily measurements from 497 ASOS and AWOS stations in the Global Hourly Integrated Surface Database (mostly independent from the official homogenized NOAA data) and computed similar trends for each station separately. I then took the median of all reported trends from within each of the 48 states, and did a 48-state area-weighted temperature trend from those 48 median values, after which I also got +0.26 C/decade. (Note that this could be an overestimate if increasing urban heat island effects have spuriously influenced trends over the last 50 years, and I have not made any adjustment for that).
The importance of this finding should be obvious: Given that U.S. energy policy depends upon the predictions from these models, their tendency to produce too much warming (and likely also warming-associated climate change) should be factored into energy policy planning. I doubt that it is, given the climate change exaggerations routinely promoted by environment groups, anti-oil advocates, the media, politicians, and most government agencies.
#
HT/Cam_S
And here’s a musical coda from The Specials: Too Hot. — charles
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Not only that, but how much warming is spurious already (UHI, site changes etc)?
Anthony Watt’s Surface Station Project (latest 2022) will give that answer for CONUS.
Aren’t there more than 36 models in CMIP6? What about the full model population?
@moderator Rotter
How long dioes it take to generate those AI graphics? Some are very related.
Understand the need for infringement problems. Useful tech.
Joe Biden’s climate emergency proclamation is two years old. According to NOAA it is 0.052 deg C warmer on average now than when he took office. I’m pretty sure his 3 trillion climate emergency bill will be spent judiciously to prevent any more of this disastrous heating.
The biggest problem with computer models is getting them to matchup to reality.
The modellers done too much, much too young.
And the elephant in the room is? … 0.1º change per decade is NOT alarming..
For the US, it’s around 0.26C over 50 years. Closer to 0.05C per decade.
It’s 0.26°C / decade. About 1.3°C over 50 years.
Bellman,
Before you quote a change of anything over 50 years, you need to understand the measurement uncertainty 50 years ago, like 1970. In their 2020 State of the Climate report, BOM claim
“Australia’s climate has warmed on average by 1.44 ± 0.24 °C since national records began in 1910″
Apart from national T records actually going back to 1856, the BOM appear to think that uncertainty has been constant and symmetrical since 1970 or so.
One small example disproves this. Metrication was on 1 Sept 1972. BOM estimate about 0.1 to 0.15C of change from metrication, when rounding from Fahrenheit to Celcius. They do not include this error in their figures because they claim inability to distinguish it from the Great Pacific Climate Shift of the mid-1970s. So the error remains. It is not symmetrical, it is only towards seeming warmer, so their +/- expression is wrong. It is also (maybe) 0.15 of the 0.24 total uncertainty, a guesstimate by the BOM of uncertainty that is quite implausible, a product of choice of certain statistics that seem inappropriate as well as weightings for land ar4eas in claculating national figures.
When you account for all of the irregularities, not just metrication, you get uncertainty much larger than 0.24. (All numbers here are 2 sigma).
A group of us who have worked on these numbers from the late 1980s have considerable familiarity with the uncertainty. There is no consensus number, but many of us seem not far away from drawing a line through 1.44 +/- 0.24 C and a better estimation of numbers giving 0.6 +0.7/-0.4C for Australian land Taverage change since 1910. (It is less if we start in 1890). There are, as yet, unexplained large changes since year 2000, as colleague Chris Gillham explains in link 3 below.
Geoff S
Links:
http://www.waclimate.net/round/index.html
Uncertainty Of Measurement of Routine Temperatures–Part Three – Watts Up With That?
http://www.waclimate.net/aws-corruption.html
I’ve asked what Dr Spencer considers the uncertainty to be of this 50 year trend. For some reason nobody seems to object to quoting the trend with no confidence interval as long as the claim is that there has been less warming than the models predict.
But when I correct a trivial factual error , that the warming quoted is 0.26 per decade, and not over 50 years, suddenly it’s back to measurement uncertainties.
By my calculations, and nothing to do with measurement uncertainties, the 95% confidence interval for the 50 year trend is around ±0.09°C / decade.
Your reference to Part Three of your uncertainty work in WUWT is really good. It is a prima facie case of BOM malfeasance. People that haven’t ought to review it, Geoff.
Not according to the data.
What data would that be?
I’m talking about the data that is used by Dr Roy Spencer in this very article. It’s clearly stated in the graph at the top that the warming rate is 0.26°C / decade, and not 0.26°C / half century. You can check the source yourself.
If you think this is wrong, take it up with Dr Spencer, not me.
From Dr. Spencer’s blog.
From Dr. Spencer’s blog.
Almost half of the all time hottest temperatures in the 50 US states were set in the 1930’s.
https://en.wikipedia.org/wiki/U.S._state_and_territory_temperature_extremes
RADIATIVE FORCING BY CO2 OBSERVED AT TOP OF ATMOSPHERE FROM 2002-2019
https://arxiv.org/pdf/1911.10605.pdf
“The IPCC Fifth Assessment Report predicted 0.5080.102 Wm−2RF resulting from this CO2 increase, 42% more forcing than actually observed. The lack of quantitative long-term global OLR studies may be permitting inaccu-racies to persist in general circulation model forecasts of the effects of rising CO2 or other greenhouse gasses.”
Here is a related data presentation about Australia.
Our CSIRO government research agency has 2 models in this CMIP, named ACCESS CM2 and ACCESS ESM1.5. On Roy’s bar chart comparison their anomaly temperatures for the US are 0.52 and 0.57, so they come in amongst the highest projections of the 36.
CSIRO produced a CMIP6 comparison shown in this figure showing CSIRO’s Australian data:
http://www.geoffstuff.com/csirocmp.jpg
I have added some of theie text to the figure caption, plus the link to the larger CSIRO description.
I have also added as big green asterisks the UAH satellite temperature anomalies for the years 1980, 1990, 2000, 2010, 2015 and 2020. Tes, I know these are Version 6 with a different baseline to the animalies, but look at the trend!
CSIRO has simulated Australia cooling far faster than UAH.
More,
http://www.geoffstuff.com/uahoct.jpg
Geoff S
Exceeded my best typo count.
“anomalies”, “Yes”, “their”, “warming” not cooling.
No excuses. Apologies.
But look at the implications. Geoff.
The UN IPCC CliSciFi propaganda mill uses various graphing tricks so as to hide the fact that their models do not replicate the late 19th Century and early 20th Century cooling nor the 1910 to 1945 global warming.