Best Climate Change Temperatures

By Andy May

I just gave an informal Zoom talk to a small group on measuring climate change through temperatures. The host, Dave Siegel, recorded it and has posted the presentation here, if you want to view it. It is about 15 minutes, plus some discussion afterword.

The PowerPoint slides can be downloaded here, and the slides with my notes can be downloaded here.

The key points of the talk are:

  • The IPCC and I agree that temperature is a key indicator of the changing state of the climate system.
  • The IPCC has traditionally used the global mean surface temperature (GMST) to estimate global temperature change, it has an organized database behind it, but atmospheric temperatures are very chaotic, so it might not be meaningful from a climate perspective.
  • The new GSAT (global surface air temperature) model-based measure of warming is highly problematic, if it is introduced, as planned, in AR6. It is calculated with a model from GMST and increases the warming rate by 4%. Models suggest that GSAT is warming faster than GMST, but the data that exists does not support this extra warming. The data we have are mainly night marine air temperature measurements from ships.
  • The ocean mixed layer is in constant communication with the surface and has 27x the heat capacity of the entire atmosphere. It covers 71% of Earth’s surface and does not react to short-term chaotic swings in atmospheric temperature. As a result, it is a more stable long-term record of climate change.
  • The deeper ocean, below the mixed layer, is a record of temperatures in the past.
  • A model is needed to build a good temperature record from current deep ocean temperatures plus proxies from ocean floor sediments.
  • The phrase “climate change” is redundant, climate always has always changed and always will, we should just say “climate.”

The final slide of the presentation illustrates what can be done, it uses data from Yair Rosenthal, 2013, Science.

The left-hand graph shows a temperature reconstruction by Yair Rosenthal and colleagues in their 2013 paper in Science. On the right we see a location map and a temperature profile for the Makassar Strait from the University of Hamburg database.

The left-hand graph shows a temperature reconstruction by Yair Rosenthal and colleagues in their 2013 paper in Science. They use bottom-dwelling foraminifera in the Makassar Strait, between Sulawesi and Borneo in Indonesia. The water at about 500-meters, where the forams live, is sourced from the Southern Ocean near Antarctica, the southern Indian Ocean and the North Pacific. This location is ideal for checking the 500-meter water temperature for much of the Southern Hemisphere and a portion of the Northern Hemisphere.

Deeper water is more insulated from the surface and the trends reflect longer-term climatic changes, uncontaminated with atmospheric variability.

On the right we see a location map and a temperature profile for the Makassar Strait from the University of Hamburg database. The database is a high resolution (0.25° latitude and longitude) monthly series that uses all available data from many years. This profile gets most of its data from 2004-2016. It shows an average temperature, at 500 meters, of about 7.7°C. Thus, this area, at 500 m, warms about 0.5°C from the depths of the Little Ice Age. Here the low temperature was 7.2°C in 1810.

The Holocene Climatic Optimum is identified on the graph, and in this strait, the temperature was often over 10 degrees, the Medieval Warm Period was about 8.5°C, much warmer than today.

In summary, the data we need to reconstruct Holocene, and older temperatures are in the oceans and in ocean sediments. Ocean temperature reconstructions represent much more of Earth’s surface (defined as from the ocean floor to the top of the atmosphere) than any land- or ocean-based measurements in the atmosphere. The atmosphere is too chaotic and unstable to give us representative climatic trends. Ocean temperatures are more stable, usable, and easier to compare to paleo-temperatures.

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Philip Mulholland
March 26, 2021 2:24 pm

If you want to study long term trends, use a damped system.

shrnfr
Reply to  Philip Mulholland
March 26, 2021 3:19 pm

You are damped if you do and damped if you don’t.

Reply to  Philip Mulholland
March 26, 2021 5:19 pm

No one disputes that the oceans are dampening the atmospheric climate response to a forcing, us occupying the lower ~3 km of the atmosphere.
But alarmists imagine an underdamped system that overshoots to thermageddon when forced by a small CO2 rise that is mostly LWIR saturated already by pre-existing CO2 and water vapor. They live in fear and worry — storytelling bedwetters like Mann.

I see an overdamped system, that suppresses and undershoots and would take a millennia to respond to a CO2 impulse forcing like anthropogenic CO2 if there weren’t so many other coupled internals and external forces that can’t be separated, by which time so many other negative feedback ‘forcings’ are in play at different time scales it is a chaotic response, until orbital changes drives the system to a new attractor, the Ice Age. We live in a blessed time of a Modern Climate Optimum. No warming climate crisis, not now nor in the future. Cold is in our future.
Climate change policy and energy poverty is what we must fear from the Marxists.

Pillage Idiot
March 26, 2021 2:35 pm

A very interesting and compelling study.

Do they have data back to the major temperature swings going into and out of the Younger Dryas? A correlation of oceanic temperatures with the glacier dome temperature records through that period would indicate a robust data set.

David A
Reply to  Andy May
March 27, 2021 2:00 am

A very interesting post in my perspective. The atmosphere is clearly a thin sandwich between the1300 watts per sq m solar insolation at the top, and the 27x heat capacity of the mixed layer of the oceans. Very powerful study IMV.

I do however think going back to just before the glaciation ended may be very informative. I recall some recent WUWT posts that showed very warm ocean T then as well, perhaps warmer then 10 k years ago.

The 500 m flux appears larger 10 k years ago, with reduced swing variations as we move towards the presence. ( A clue to something)

I have a slowly formulating thought that during our glaciation phase, the atmosphere and oceans are less coupled then during interglacials, and the oceans slowly gains energy that builds from the bottom up during glaciation, as the tropical T varies little, a colder slightly less cloudy atmosphere allows increased solar insolation into the oceans, and much greater ice areas at the poles insulates in the very very slowly building ocean heat content, which slowly warms the oceans from the bottom up.

During an interglacial the oceans slowly give up that heat due to the much smaller ice caps, with the greater amplitude swings being due to greater then today cold water flux of diminishing land ice. As the reduced land ice flux to the oceans diminishes, the T swings moderate, the sea ice reduces, the oceans slowly cool, the ocean atmosphere coupling increases, producing the ever reduced amplitude, step down atmospheric T we observe in this interglacial.

As the oceans cool, eventually the interglacials ends, the ice slowly locks in more ocean heat from expanding sea ice, the not released to the atmosphere ocean heat very very slowly warms the oceans, from depth at first, so not affecting the atmosphere, relatively decoupling the atmosphere from the ocean compared to an interglacial. Ocean water that moved Poleward, moves back towards the equator, not giving up it warmth to the atmosphere due to greater sea ice, and slowly warms the ocean from depth, very gradually working towards the surface.

The bottom of the expanding sea ice is somewhat insolated from warmer ocean by a saline density gradiant, and the much colder ice age atmosphere, no longer receiving ocean energy near the poles, is still conveying adequet snow fall ( the water vapor producing tropics and sub tropics are ice free and receiving great insolation) to build the ice sheets and build the sea ice ice from the top, ( unlike today) as the ocean atmosphere coupling is separated more then during an interglacial.

Well it’s a thought…

March 26, 2021 2:37 pm

Models suggest that GSAT is warming faster than GMST, but the data that exists does not support this extra warming.

Oh, why not just change the data ?

March 26, 2021 2:39 pm

The surface temperature cannot exceed 30C and the bottom temperature in this region is close to 3C. The only way that the temperature at 500m can alter is by the rate of change of net evaporation; evaporation less precipitation.

An increase in temperature at 500m requires a reduction in evaporation rate such that heat conduction downward has more effect than the upward flow of deep water due to net evaporation.

Less net evaporation could be the result of the persistence presence of a warm pool because they create local convergence, increasing local precipitation.

I expect your chart is a better indicator of evaporation/convergence/precipitation than the actual surface temperature.

If you look at a temperature profile across the tropical South Pacific you will see that the 10C and 20C isotherms diverge considerably from 120W to 180E:
comment image
This is due to higher rates of net evaporation on the eastern side compared with the western side where the warm pools occur. So the surface temperature not changing much but the temperature at depth considerably higher in the west compared with the east.

Reply to  Andy May
March 26, 2021 2:59 pm

I agree that the surface temperature measurements are noisy but nothing that happens at 500m is directly indicative of what is occurring on the surface from the perspective of temperature indication.

I am just focusing on the Nino34 region. It is a well known region in terms of being significant to global weather. The method that NCEP have used to interpolate moored buoy and satellite data appears to be producing a reliable result. I am less certain about the NCEP data set away from the moored buoys.

The best method for a global temperature may be to interpolate ARGO surface data with satellite data; taking a page from Reynold’s song book.

Reply to  Andy May
March 26, 2021 3:37 pm

Find twelve sites well spread across the globe in latitude and longitude that shows the same trend. Then it would be more compelling. Even a couple more away from a tropical warm pool would start to build a better picture.

My point is that response of a tropical thermocline is a function solely of net evaporation rate that is not directly linked to the surface temperature. So it is not only damped but could be meaningless with regard to temperature.

David A
Reply to  Andy May
March 27, 2021 2:15 am

I agree, it is just very long term, and the 60 to 80 year atmospheric ocean surface, and atmosphere surface flux, hides the longer interglacials variations. CAGW skeptics show the longer term interglacial atmospheric charts regularly.

Clearly what happens to the plus 27 times mixed layer ocean T is going to dominate atmospheric T over greater time, and the slowly reducing mixed ocean T over time, very well fits what is observed in the atmospheric T of this interglacials.

The mixed layer ocean T you show here, is yet another dagger into Michael Mann’s attempt to wipe out the MWP and falsely establish CO2 as a control knob.

The ocean heat content wags the tail of the atmosphere T.

Great post and study!

David A
Reply to  David A
March 27, 2021 9:27 am

Correction, Andy shows the 500 m ocean T flux, not the mixed layer 0 to 70 m, yet that mixed layer is greatly affected by the 500 m level T, as observation based models show rising anomaly waves, warm and cool, migrating into the mixed layers, affecting the extremes of El Nino – La Nina flux.

Reply to  RickWill
March 26, 2021 3:11 pm

I know why the global surface temperature is stuck where it is.

I know there is no “greenhouse effect”.

I know that CO2 cannot alter the global energy balance.

I know why climate models fail.

What I am yet to learn is how to convince a climate modeller that their work is poo. Current strategy is to show how badly they predict temperature in the Nino34 region.

Australians were told a little over a decade ago that the dams would never fill again and vast sums were spent on water recycling and desalination infrastructure. Then comes the 2021 La Nina and Australia is awash. CSIRO CIMP3 model indicated there would not be another La Nina after 2010.

Scissor
Reply to  RickWill
March 26, 2021 3:45 pm

Upton Sinclair said, “It is difficult to get a man to understand something, when his salary depends on his not understanding it.”

old engineer
Reply to  Scissor
March 26, 2021 5:40 pm

It’s more than just money. They are ego involved with their model. Criticizing their model is like criticizing their child. In a lot of ways their model is their child.

Bob boder
Reply to  old engineer
March 27, 2021 8:27 am

It’s more then that, they think they are saving the world. It’s a Messiah complex.

Rud Istvan
Reply to  RickWill
March 26, 2021 4:55 pm

Rick, a gentle disagreement. You cannot ‘know there is no greenhouse effect’ when Tyndall experimentally proved the opposite in 1859. Overstating the case does great credibility harm. Here and elsewhere. Sort of like Monckton.
The correct (in my opinion) GHE question is how much—does it matter? Unlike Monckton’s nil, my conclusion based on many posts here and at Judith’s is that the ECS is about 1.65, so is there BUT does NOT matter.

Reply to  Rud Istvan
March 26, 2021 5:37 pm

Rud
I am not questioning the radiating properties of certain atmospheric gasses. They are essential to the way the atmosphere operates.

The “greenhouse effect” is bedded in the reasoning that cloud albedo is essentially fixed or has some positive feedback and the surface temperature is 33 degrees C warmer than the average radiating temperature so the “greenhouse effect” is providing that 33C. That is WRONG.

The surface temperature is regulated by two powerful thermostatic processes. Formation of sea ice at the poles at -2C and formation of persistent high level cloud (air ice) over water at 32C but regulated to 30C through convergence. So the average surface temperature is 14C give or take an immeasurable amount. The radiating temperature will be whatever is the result of the cloud required to regulate the maximum surface temperature to 30C.

The climate modellers are looking at some fine energy balance and taking clouds as a given. No climate model uses a physics derived determination of cloud – all clouds are just parameterised.

gbaikie
Reply to  Rud Istvan
March 26, 2021 5:39 pm

“The correct (in my opinion) GHE question is how much—does it matter?”

If we were going into a glaciation period {and we sort of are, but I mean going in direction of getting too cold, too fast- and so a lot humans going to die as result} then having a plan of dumping vast amount CO2 into the atmosphere, seems like a plan which will fail to stop the cooling. Nor I think adding different greenhouse gases to atmosphere, like the useful to heat a home, methane gas, would also “not work” to warm Earth. Nor would “super greenhouse gases”, be useful idea in order to do something about stopping things like 1 mile of ice over New York city.
What greenhouse gases don’t do, is make hotter days. “More” GHE does not equal hotter. More GHE is more uniform global temperature.
And reason Earth doesn’t have a very uniform global temperature is because, Earth has a cold ocean.
Or biggest lack of GHE that Earth presently has, is it has a cold ocean.
Or Earth is in an Icehouse global climate, in which the definition of icehouse climate includes having a cold ocean.
Our ocean is currently about 3.5 C, if it was 5 C, then it’s still a cold ocean. But 5 C ocean is huge greenhouse effect in regards to our present greenhouse effect.

Reply to  Rud Istvan
March 26, 2021 5:46 pm

Tyndall did not “prove” a greenhouse effect.
He only proved that carbon dioxide, and other gases are what are now called greenhouse gases.

Nor did Tyndall measure or control how much energy he generated and what portion CO₂ warmed or reradiated.

Reply to  ATheoK
March 26, 2021 7:06 pm

Tyndall did not “prove” a greenhouse effect.”

Correctamudo.

fred250
Reply to  Mike
March 26, 2021 9:45 pm

A glass jar is NOT representative of the planetary atmosphere.

Tom Abbott
Reply to  ATheoK
March 27, 2021 12:44 pm

Let me throw this in here:

https://wattsupwiththat.com/2018/09/11/the-new-york-city-climate-museum-really/

“So I [David Middleton] looked up Möller (1963) and found the abstract to this seminal publication…

On the influence of changes in the CO2 concentration in air on the radiation balance of the Earth’s surface and on the climate

F. Möller

Abstract

The numerical value of a temperature change under the influence of a CO2 change as calculated by Plass is valid only for a dry atmosphere. . .

The effect of an increase in CO2 from 300 to 330 ppm can be compensated for completely by a change in the water vapor content of 3 per cent or by a change in the cloudiness of 1 per cent of its value without the occurrence of temperature changes at all. Thus the theory that climatic variations are effected by variations in the CO2 content becomes very questionable.”

end excerpts

Yeah, I don’t think the science is settled yet.

Reply to  Tom Abbott
March 28, 2021 4:28 am

The funny thing is that the #Exxon Knewtards led me to Möller… 😎

Tom Abbott
Reply to  Tom Abbott
March 28, 2021 4:53 am

It looks like Möller and Willis Eschenbach are on the same page. 🙂

Reply to  Rud Istvan
March 27, 2021 6:56 am

Anthony’s CO2 jar experiment demonstrated that increased CO2 did not cause an increase in temperature. Further, there are numerous charts showing the eons long temperature versus CO2 and they show no cause and effect.

Professor Hoyt Hottel conducted numerous experiments showing that CO2 had almost zero emissivity below 33 C. The specific heat tables list no addendum about warming of CO2, the Shomate equation does not say anything about it, the NIST data sheet for CO2 says nothing the last I looked, infrared causes vibration not translation and there is no explanation for how the vibration turns into translation, finally according to Planck’s constant each CO2 molecule at best can have and energy output of 1.325E-20 J.

Nope, CO2 does not cause climate change.

F2D4C325-74A7-4A35-83AC-7F13B53363F9.jpeg
Joseph Campbell
Reply to  mkelly
March 27, 2021 8:20 am

Thank you, mkelly. Look: Does anyone suggest that the atmosphere is constantly in an energy-unstable state? It is NOT, which it would need to be in for CO2 to act as some form of “greenhouse” gas. The Connollys have shown conclusively that the atmosphere obeys the ideal gas law, and thus the gases that make up the atmosphere obey the ideal gas law. Thus, as mkelly notes above (“[t]he specific heat tables list no addendum about warming of CO2″), there is no reason to believe that CO2 picks out specific “radiative-generated” joules from any other, so Cp of CO2 is just its Cp…

Drake
Reply to  Rud Istvan
March 27, 2021 9:47 am

Over 15 years ago I first became a AGW skeptic after reading a blog post about the original experiments to measure the temperature of deep space. The poster noted that the temperature determined over 100 years before was the same as using the same method at the current time. That is, when looking to space in a low humidity cloudless night, using the same instruments from the same location, there was NO DIFFERENCE in the temperature determined. He then stated there was a difference in the atmosphere, the addition of substantial more co2 by % His conclusion was that if co2 was so important, as shown by Tyndall’s lab experiments, then the temperature should be different. That started me paying attention to the science and led me to first Climate Audit and then WUWT.

I cannot find the articles that I read way back then. Perhaps you can provide a link, Rud, to something that disproves what that long ago blogger posted.

This same blog post mentioned that if the sea level was rising so fast, than the earth’s rotation should be slowing due to more water at the equator. That also made sense to me, but I now know there a way more influences on the earth’s rotation than the shift of mass to the equatorial region. Too many for me to understand. But a quick search brings this link:

https://www.timeanddate.com/time/earth-faster-rotation.html

According to this article 2020 had THE SHORTEST DAYS ON RECORD. Sounds like THE HOTTEST YEARS EVAH.. How is that possible if the sea level is rising AT AN EVER ACCELERATING RATE?

If I have displayed ignorance of the science behind these two scenarios, I hope to be corrected/educated as to the scientific reality. I know it is not your job to educate me, but I hope ANYONE reading this can help me out.

Thank you in advance,

Drake

meab
Reply to  Drake
March 27, 2021 12:45 pm

Ocean rise is mainly from 1) Land grounded ice mass melting and 2) thermal expansion. You have to first figure out how much rise is from each. Recent estimates have 2/3 of the increase coming from #1 and about 1/3 coming from #2. The change in the moment of inertia of the Earth and therefore the change in rotation rate is different for the two main causes of ocean rise.

For #1, since the land grounded ice was always at a higher elevation than the sea, the moment of inertia drops when the glacier melts into the sea. The equatorial bulge causes the Earth to have a moment of inertia about .3% greater than if the equator was the same diameter as the poles. So as the water redistributes, there would be rotational slowing. So the two effects partially compensate.

For #2, the mass of the ocean stays the same but the inertia increases (by a complicated formula with the fifth power of the radius difference of the shell divided by the same to the third power).

In any regard, the ocean rise is quite small – about 7 inches in 100 years with a correspondingly small change in the radius – a factor of about 1.000000029 in 100 years, or 1.00000000029 per year.

The earth’s rotation rate is also affected by tidal drag transferring rotational energy to the Moon, the mass distribution of the crust (plate tectonics, you can sometimes actually see the rotation rate change after a big earthquake), the rate and direction of spin of the Earth’s molten iron core, and the drag of the core on the mantle. Since we really don’t have a good understanding of what the core and mantle are doing, we can’t accurately separate the changes in rotation rate into its causes.

Drake
Reply to  meab
March 27, 2021 8:04 pm

Thanks, so as I thought it is not so simple. The rotation has been making records for “shortest days evah”, when ocean rise should be making the days longer. One or many other things must be counteracting that effect.

Maybe the climate modelers can do a computer program, if they ever figure out how to actually provide for ALL effects on the climate, like length of day, That must have SOME influence on the climate. I mean the earth isn’t just a flat black body. I am sure they have taken that into account.

Reply to  Andy May
March 27, 2021 6:37 am

I hate to keep harping about the term noise but I believe it is an important concept when dealing with the warmists. There is no “noise” when dealing with temperature measurements. Noise is extraneous information that interferes with the intelligence that is being captured. Nothing like that exists with temperature measurements unless one wishes to address siting and other complications.

What you have is VARIANCE in the signal. That would be akin to measuring the difference in volume of an audio tone from the softest to the loudest. The current practice of using averaging of averages of averages to determine differences simply hides the original variance in daily temperatures.

Ignoring a variance in degrees when looking at “anomalies” of 1/100th of a degree is foolish. Ignoring the uncertainty in measurements is also foolish. We are going to be spending trillions and trillions for the tail wagging the dog.

Reply to  Jim Gorman
March 28, 2021 4:54 am

Noise is anything extraneous to the signal…

In signal processingnoise is a general term for unwanted (and, in general, unknown) modifications that a signal may suffer during capture, storage, transmission, processing, or conversion.[1]

Sometimes the word is also used to mean signals that are random (unpredictable) and carry no useful information; even if they are not interfering with other signals or may have been introduced intentionally, as in comfort noise.

https://en.m.wikipedia.org/wiki/Noise_(signal_processing)

Bill Treuren
Reply to  RickWill
March 26, 2021 3:11 pm

does it not depend on provenance?

Reply to  Bill Treuren
March 26, 2021 6:44 pm

The response of the oceans is relatively slow. They have shallow circulation taking about a year in each major basin driven by prevailing wind but much slower one way flow from poles to equator between 1000m and 2000m.

I believe this deep flow is driven by the atmospheric circulation lifting water in the tropics and dropping it at higher latitudes. The actual flow rate is not much.

The evidence is compelling for evaporation driven equatorial flow at depth. I have not done the mass balance for the actual flow but you get some clue for how the fresher water tongues its path from shallow depth at the poles to the 1000-2000m channel below the temperate zones before being drawn upward into the tropical region:
comment image

Changes in evaporation can have an impact within decades for the local thermocline. Time frames could be thousands of years for the deep water equatorial flows. Nothing changes much below 2000m in terms of human timeframes.

One thing for certain is that any temperature change at the surface in the tropics that does not alter evaporation rates will take thousands of years to be reflected at 500m. That depth is far more responsive to evaporation rate than surface temperature. If the zone shifts from divergence at say 28C to become net zero evaporation at 30C then the temperature at 500m would warm by 2C within a hundred years.

David A
Reply to  RickWill
March 27, 2021 2:41 am

And yet, over this 10 k year period, The past known step downs in atmospheric T, as we approach the end of this interglacial, clearly shown by everyone except Mann, and the mixed ocean T, which is not at 500 meter depth, but extends down to that depth, clearly reflect the atmospheric step down gradiant, and most certainly drive it.

March 26, 2021 2:43 pm

Ocean currents are also chaotic on these time scales. Proxies are inaccurate to several unknown degrees. Global averages require random samples and will have large confidence intervals. Taken together it is very unlikely that we can ever know what the global temperatures were on the century to millennial scale. It is not clear we know what they are today. The flip side of intrinsic unpredictability is intrinsic unknowability. All we get for the big money is dueling graphs.

RicDre
Reply to  David Wojick
March 26, 2021 3:10 pm

“All we get for the big money is dueling graphs.”

This is one of the best (and most accurate) comments I have heard in a while. Thanks.

Crispin Pemberton-Pigott
Reply to  RicDre
March 26, 2021 11:33 pm

“A chart is an inaccurate representation of a partially understood truth.”

[Do any of you know who said that?]

Drake
Reply to  Crispin Pemberton-Pigott
March 27, 2021 10:04 am

OK you made me look.

I didn’t find that one yet, but I did find this one, perfectly suited to any discussion of “Climate Models”. But, I will give you the author.

I never guess. It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts.
Sir Arthur Conan Doyle, Author of Sherlock Holmes stories

Reply to  David Wojick
March 26, 2021 3:25 pm

It is not clear we know what they are today

This is the truth.

Ask anyone claiming that the globe is warming to tell you what the temperature was in 1950 (or any date in the past) and what it is today.

Also the descriptor “they” is correct because every official body responsible for a global dataset has their own view on what the global average temperature is and how much it is increasing by (note none would be silly enough to claim it s reducing). There is no single temperature value that the bodies can agree on.

It should be a requirement that each IPCC report come out with a number on the consensus global temperature at the date of the report. Imagine how long it would take arguing the fourth decimal point.

Reply to  RickWill
March 27, 2021 3:59 am

They should also have to report the range of estimates to show how little consensus there was.

Rud Istvan
March 26, 2021 3:12 pm

Andy, nice presentation—and btw am enjoying your new book, now on chapter 4.
A quibble with your slide 2. Its ending question is why anomalies are used. Unfortunately, anomalies wash out the several degrees C disagreement between the various CMIP5 model average absolutes, another model weakness Judith Curry pointed out in a presentation some years ago, footnoted if I recall correctly in my essay Models All the Way Down in ebook Blowing Smoke.

I don’t think the ‘instumental’ GMST or GAST are fit for purpose. Too many problems with surface stations (UHI being one, siting another), too little global coverage. And SST was biased by trade routes and ship ladings prior to ARGO. We CAN go back in time at least qualitatively, as your slide 9 shows. Or, as tree stumps emerge from under melting ice to show the ice had melted for long periods before.

March 26, 2021 3:27 pm

Call NASA…NASA knows everything about climate….NASA knows man increased CO2 by 47% and caused 1.5 F increase in temp since 1880…..ask NASA what the ideal temp of earth should be and how much CO2 is ideal….will you receive an answer? I doubt it. NASA is kinda busy indoctrinating kiddies into their climate belief system….sort of a NASA Youth League, eh? NASA will be there when Uncle Joey convenes a Big Three Conference with Russia and China to decide our Climate Future.

Tom Abbott
Reply to  Anti_griff
March 27, 2021 12:53 pm

The Big Three and Climate ought to be a real circus.

Here ole Joe will be serious as can be about saving the Earth, and the Russians and the Chinese will be shaking their heads in agreement while they laugh behind his foolish back.

Yes, Mr. Biden, the Chicoms and Russians will be happy to cheer you on as you ruin the U.S. economy chasing a Climate Change science fiction scare story.

Vuk
March 26, 2021 3:42 pm

What is knowable is that tropics cover ~40% of the Earths surface and that intra-annual temperature varies very little. Polar regions cover ~20% of the surface but intra-annual temperature varies about ~30C. The other 40% of the surface is most likely halfway between two.
Simple calculation shows that global intra-annual temperature varies about 10.5 C degrees, and according to NOAA that is more or less global temperature variability during the last half a million years.

Vostok_TemperatureCO21.png
Reply to  Vuk
March 26, 2021 5:58 pm

IF THAT GRAPH IS CORRECT, IT IS REAL SCARY OR FUTURE GENERATIONS…..5 relatively brief peaks and 4 dives to ice ages….next dive seems not too far away, no? Abundant cheap electric power from MSRs can provide grow lights for food in warehouses or caves…sort of greenhouses even.

Waza
March 26, 2021 5:39 pm

Andy
Thanks for providing the very informative presentation.
In addition to being informative, I gained a new “weapon”.

The discussion with Pat Frank provided a new phrase – “ coupled oscillators”
In any battle with an alarmist, I can ask him/her to explain the maths associated with the energy transfer of the phenomenon they are bsing about.

March 26, 2021 9:26 pm

Andy gave an excellent presentation.

I was honored to participate. Thank-you, David.

Reply to  Pat Frank
March 27, 2021 6:56 am

Let me add my thanks to you and Andy for an enlightening podcast. The term “coupled oscillators” certainly helps me expand on something I posted recently.

All of the variables in climate are continuous functions, just like a vibrating violin string. They each have their own frequency and power. Temperature, clouds, humidity, insolation all vary from moment to moment and location to location. Maxwell was a genius for developing equations that still perfectly describe the relation between electric and magnetic fields, just two variables. Until we are able to develop similar equations for all the variables involved in climate we are going to be wandering in the dark hoping something will fall out that leads us to a correct predictor. I won’t hold my breath.

March 26, 2021 11:19 pm
  • “The IPCC has traditionally used the global mean surface temperature (GMST) to estimate global temperature change, it has an organized database behind it, but atmospheric temperatures are very chaotic, so it might not be meaningful from a climate perspective.”

It’s not meaningful from any perspective, except to scare people.

fred250
Reply to  Jeff Alberts
March 27, 2021 5:11 am

except to scare people.

.
I still haven’t figured out how a degree or so of warming out of the coldest period in 10,000 years, should actually SCARE anyone who has more than a couple of functional brain-cells.

YIPPEE! should be the response. !

March 27, 2021 3:43 am

@ The ocean mixed layer is in constant communication with the surface and has 27x the heat capacity of the entire atmosphere.
It is surprising that the contribution made by motor ships, especially the world merchant fleet, to global warming has never been questioned. High-traffic sea areas such as the North and Baltic Sea are suitable as a model case.
“Activities at sea contribute to warming. The Baltic Sea shows how it’s done.”
https://1ocean-1climate.com/the-influence-of-the-baltic-sea-climate-reinforced-by-humans/