Guest Post by Willis Eschenbach [see update at the end]
Over on Twitter, Michael Tobis made the claim that the 1979 Charney report entitled “Carbon Dioxide and Climate: A Scientific Assessment” was a “triumph of 20th century meteorological science”, in part for predicting “surface warming tending to be concentrated in polar regions”.
This got me to thinking and when I think, I think about actual observations. So I went and got the UAH MSU satellite data for the temperatures of the lower troposphere (the part of the atmosphere closest to the surface).
Using that data, I calculated the temperature trends by 1° latitude band for the area that the satellite covers (85 North to 85 South). Here is that result:
UAH MSU T2LT (lower troposphere) satellite data.
A “triumph of 20th-century meteorological science”?
Hardly … this result is totally unlike what Charney et al. predicted. Not just a little different. Not even in the same ballpark.
My very best regards to everyone on a sunny summer day … going outside now to get some work done.
w.
[UPDATE] My thanks to Nick Stokes, who pointed out in the comments that Charney was talking about the surface and I’d graphed the lower troposphere. So I’ve rectified that below, where I show both the surface (white) and the lower troposphere (red) temperature trends. Lower troposphere temperatures are red as in Figure 1. Note the change in scale from Figure 1 necessary to encompass the surface temperature trends.
Hmmm … not sure what to say about that. The surface trends shown in white are not too far from a straight line from 85°North (top right) to about 60° South (bottom left). Also, much more of the surface is actually cooling (trend below zero) and the surface at ~ 60° South is cooling more than the lower troposphere trends.
I do love exploring the data, always more to learn.
[UPDATE 2] In the comments, esalis said:
We in Finland are on the white straight line of the graph between 60 and 70 lat. As far as I know we have not had such an increase in warming towards north. Could you plot as well along longitudes?
Thanks, esalis, for moving the discussion forwards. Here you go:
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Willis Eschenbach: We in Finland are on the white straight line of the graph between 60 and 70 lat. As far as I know we have not had such an increase in warming towards north. Could you plot as well along longitudes?
esalil, I’ve added this to the head post.
Regards,
w.
Funny thing tho, the high-summer Arctic temps continue to be avg/slightly below avg & increases are in the colder seasons. That seems like something “good”, not “bad”.
If I remember right, satellite temperature data is inferred from upward radiation? So in a sense, rather then a direct measurement, it is proxy-like (they have to tease the temperature data out of the noise using assumptions) and is subject to being tweaked or misinterpreted.
As long as the processes to tweak the data remain the same and there are no variances caused by replacing equipment, then a trend should be valid – but still, I would be cautious about giving the data too much credence.
For example, if low level thin (almost invisible) clouds where to increase, I imagine this would change the temperature data but not reflect an actual temperature change (or at least not reflect it accurately). I am not an expert on satellite data so this is all speculative – I just remain cautious.
What is really needed are a set of real direct temperature measurements established in pristine areas to validate the satellite data. Using a few land temperature measurements taken at the end of runways makes me cringe.
UAH has been checked against weather balloons. That is “real,” “direct,” and “pristine.”
The lower troposphere should warm at least as fast as the surface, so its trend is an upper-bound, not an exact match to the surface.
The balloons are not perfect. Some discrepancies have been found, in China for example.
https://link.springer.com/article/10.1007%2Fs13351-019-8130-1
Interesting data. Since the time period covers the switch in the AMO cycle from cold to warm, my guess is that is what it is capturing. As someone said up thread, its ocean currents. Below is a link to a graph. Sorry, I don’t know how to make it clickable.
It’s interesting that the Arctic seems to be warming much more than anywhere else, and parts of the Southern Hemisphere are cooling.
I remember seeing some data that show temperature trends for the area above 80 degrees N as a function of (Julian) date, where temperatures from November through April are highly variable (but always below freezing), but May to September temperatures are stuck a few degrees above freezing (between 273 and 277 K) year after year. This would seem to indicate that as soon as there was ice-free water somewhere in the Arctic, evaporation would cause clouds and fog to form over the remaining ice near the North Pole, thereby obscuring the sun and limiting the temperature increases in summer.
It would be interesting to calculate the temperature trends by month or season, to determine whether the Arctic is warming in all seasons, or only in autumn and winter (when ice cover would limit evaporation, with little or no solar heat input), but (relatively) warm air could be convected from regions further south, particularly over the ocean between Greenland and Scandinavia, due to the Gulf Stream.
I hope it is not the intention to start an item every time somebody writes something grotesk on twitter on some 40 year old climate assessment / modelling report. The graph seems to indicate that there is more to climate modelling than meets the eye and the deeper you dig the more puzzles you come across.
Keeps it exciting.
Explain like I am five years old. That chart seems to show almost everywhere in the world is warming. There is an anomalous cooling at around 70°S, but that doesn’t discredit the warming everywhere else.
So the Charney report got everything right except 70°S. That doesn’t discredit the entire report. It just means someone needs to explain what is causing the cooling at 70°S.
It’s pretty obvious to me what is causing the warming elsewhere.
It is mostly loss of ice albedo. This is shown clearly in CERES satellite data.
https://www.researchgate.net/figure/Trend-in-reflected-shortwave-computed-from-annualmean-data-and-plotted-as-a-function-of_fig2_277678034
Bart Tall: “That doesn’t discredit the entire report. It just means someone needs to explain what is causing the cooling at 70°S.”
That’s a bit like saying someone just needed to explain why Newtonian mechanics failed to explain reality at very small and very large scales.
Somebody did investigate that, and realized our understanding of reality was off the mark, with Newtonian mechanics being only a subset of Relativistic mechanics.
So, this discrepancy with reality could indeed discredit the entire report.
Just want to say, your analogy isn’t really a good one, because we haven’t actually tossed out Newtonian physics. Newtonian physics is a fine approximation for most things that people do. We don’t need to do Lorentz transformations in order to fly an airplane. For spacecrafts travelling at high speeds or approaching large masses like the Sun, we use Einstein’s formulas though.
And even there, Einstein’s formulas are not perfectly predictive, and there is a small anomaly called the flyby anomaly that has been observed, but not yet explained. That doesn’t discredit Einstein’s formulas. They are still a good approximation, just like Newton’s are for many things.
Yes, an approximation valid when certain conditions are met.
The point is, saying “It just means someone needs to explain what is causing the cooling at 70°S.” seems a rather cavalier attitude. This discrepancy could be minor, or major – we don’t know.
It’s possible the cooling around 70°S may be due to the stratospheric ozone loss. Loss of ozone, a greenhouse gas, would cause cooling.
This is the modeled radiative forcing effect of just stratospheric ozone:
https://www.researchgate.net/figure/Multi-model-mean-normalised-ozone-radiative-forcing-mW-m-2-DU-1-for-MASKZMT_fig4_307653734
Jamal Munshi has several papers on the Charney sensitivity, this is his latest.
https://www.academia.edu/36536514/VALIDITY_AND_RELIABILITY_OF_THE_CHARNEY_CLIMATE_SENSITIVITY_FUNCTION?
Monthly means of Mauna Loa atmospheric CO2 concentrations are used in conjunction with surface temperature data from two different sources for the sample period 1979-2017 to test the validity and reliability of the empirical Charney climate sensitivity function. Detrended correlation analysis of temperature in five global regions from two different sources did not show that surface temperature is responsive to changes in the logarithm of atmospheric CO2 at an annual time scale. Correlations observed in source data are thus shown to be spurious. We conclude that the empirical Charney Climate Sensitivity function is specious because it is based on a spurious correlation.
The results are consistent with the movement of earth’s inner core, more north east.
I figured this a long time ago from some of my own results. Geothermal warming is changing. See comment on the relevant thread.
Willis, if you split the UAH data in two and do one chart from Dec 1978 to April 1995, and a second chart from April 1995 to the present, you would see very different changes in the polar regions.
Have to wonder what happened in 1980 to start the continuing divergence between the Northern and Southern Hemispheres.
http://www.woodfortrees.org/plot/hadcrut4nh/from:1930/plot/hadcrut4sh/from:1990/trend/plot/hadcrut4nh/from:1990/trend/plot/hadcrut4sh/from:1930
[IMG]http://i63.tinypic.com/iwjkmb.jpg[/IMG]
Have never figured how to post a graphic on this website.