Guest post by Bill DiPuccio, Science Teacher
Let’s face it, high school science videos can be boring and ineffective. I like my science with a twist of comic exaggeration. So I decided to produce a video with enough humor to keep the students awake, and enough depth to challenge them intellectually.
This 30 minute video on the Greenhouse Effect is the prototype for a possible new series: “Bill Scientific” (I gave it a personal imprint to infuse some warmth and presence). Unlike introductory videos which attempt to cover a broad field of knowledge in a short time, the goal of this prospective series is to drill down into specific, but pivotal, topics in the physical and earth sciences.
Rather than just spooning out information, each program would be designed around experiments (the simpler the better) that can be used to illuminate and verify crucial scientific principles. Students will see science in action and gain a better grasp of the empirical basis for scientific theories.
Of course, future programs will depend on the response from students, educators, and scientists, as well as securing funding. The “Greenhouse Effect” was shot and produced on amateur equipment and software. Despite these limitations, I believe the final product faithfully conveys the intent of series.
P.S. If you like the video, pass it on!
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tjfolkerts; I argued with a modeller [I suspect the Met. Office, when they tried to shoot me down]. He claimed ‘back radiation’ is an ‘accounting mechanism’ so I asked him whether he excluded the extra 333 W/m^2 from heating the air near the Earth’s surface. He did not answer.
So it seems to me that it’s a PMM of the second kind because it’s claimed that extra expansion of the air near the earth’s surface is taking place by transferring heat energy from the cooler atmosphere via the Earth’s surface. The work done is PdV hence all the claims about more hurricanes etc.
As for the term ‘energy flux’, the diagram claims 333 W/m^2 ‘Absorbed by Surface’ and 396 W/m^2 ‘Surface Radiation’, So, the ‘back radiation’ merry-go-round’ is needed to make up the S-B BB flux in a vacuum for 16 °C. This has never been measured experimentally. I can say this confidently because I was trained as a process metallurgist and did research with real experts developing pyrometers and designing thermal processes.. For natural convection with steel you need ~100 °C before the radiative heat loss rate exceeds convective, for aluminium it’s ~300 °C. Look it up in McAdams, [McGraw Hill] the process engineer’s bible. Also look up Hottel’s work at MIT:.
Prevost Exchange Energy comes from the oldest radiation law. It’s the S-B flux from the colder body to the hotter body, or both at temperature equilibrium. So it’s S-B2 in the difference equation S-B1 – S-B2 for the net flux with 2 the colder. At equal temperatures, net flux is zero so the Prevost Exchange can do no thermodynamic work. Some physicists call it a ‘photon gas’ and imagine these photons bounce off filled quantum states.
As for the mechanism, there are others besides me investigating what Planck did not work out. it is possible that the modellers don’t use 356 W/m^2 in their near surface GHG absorption in which case I could be wrong. However, if I am not wrong, they have used the PMM to predict CAGW and that’s very naughty, impossible to admit because of the politics.
Also whenever I discuss the issue with ‘climate scientists’ they argue ‘back radiation;’ is real because the pyrgeometers measure it. I have shown above why it is not real, but even if it was, because the detector is shielded from IR from the Earth’s surface, the internal reference isn’t connected in any way to the Earth’s surface. These are astonishingly bad errors.
PS I had a climate scientist argue that the reason why ‘back radiation’ did not heat up passive solar panels at night was because to overcome the thermodynamic limitation of the PMM, you need the external SW energy source, proof I think that they are going through intellectual hoops.
Another issue is that they and I suspect most physicists fail to realise that Kirchhoff’s Law of Radiation only applies at thermal equilibrium and at TOA, where convection changes to radiation, the composite emitter cannot be treated as a standard radiator. This may be new physics.with an effective emissivity to the Earth near zero.
You’re kidding – right?
This simply presents all the misinformation with some stupid inane commentary.
One of the biggest contradictions in climate science is if GHGs emit most of the longwave radiation to space – 165 by atmosphere + 30 by clouds = 195/235 = ~83% of radiation to space it is difficult to comprehend why increasing concentrations of the super emitters will result in less radiation to space.
Seems counter-intuitive – and yes I’ve seen the Nimbus charts – is it not possible the reduction in the radiative temperature implied in these charts could be offset by the increase in radiative units ?
Hell, what would I know?
Mydogsgotnonose says:
April 28, 2012 at 2:00 pm
“Also whenever I discuss the issue with ‘climate scientists’ they argue ‘back radiation;’ is real because the pyrgeometers measure it. I have shown above why it is not real, but even if it was, because the detector is shielded from IR from the Earth’s surface, the internal reference isn’t connected in any way to the Earth’s surface. These are astonishingly bad errors.”
This is basically the same thing as Professor Claes Johnson is saying about “backradiation”.
Good that more and more people is beginning to realise this.
Keep at it, Mydogsgotnonose! The thruth will be known, sooner or later.
tjfolkerts says:
April 28, 2012 at 11:27 am
Well, your example is fairly non-conventional if you using the +/- 5% to refer to accuracy as opposed to precision. It is generally accepted that the “+/-” refers to either the precision (e.g. standard deviation or standard error) of the technique or total uncertainty.
I still disagree with your argument. It does not matter if the reading is with different DMMs or the same DMM. The range for the first reading was 95.0 – 105.0 ohms and the second was 95.5 – 105.5 ohms. You simply cannot conclude that the difference in readings is 0.5 +/- 0.1 ohms, unless you are arguing that the precision of the DMM is +/- 0.1 ohms. The signal readout is not sufficient justification. This fact is independent of whether you anticipate that the resistance changes a specified amount with temperature. You need a sufficient change in temperature to overcome the intrinsic error in the measurement. When the uncertainty in the measurement is larger than the difference, you cannot know the change for certain.
I routinely perform calorimetric experiments that rely on temperature changes due to changes in resistance. We calibrate the linearity (using a range that far exceeds the uncertainty of the DMM) before and after our measurement. And, we ensure that the change in resistance of our measurement is within our calibration range. If we just assumed a change in resistance was statistically significant, then our results would be meaningless. The DMM that we use is research grade with uncertainties far less than 0.1%. Nevertheless, the repeatability of our measurements are always significantly worse than the reported uncertainty of the DMM.
Right now, it appears that you are trying to justify an argument that goes against all current statistical paradigms. You are not going to convince me that your contention has merit without a valid literature reference from a reputable statistics source.
Mydogsgotnonose is right, and a simple experiment with solar cookers proves it-
If the so-called ‘back radiation’ from the cold atmosphere to warm Earth was capable of doing any thermodynamic work, solar cookers pointed at the sky (not the Sun) would produce heating day and night. Instead, experiments show that when a solar cooker concentrates the alleged 324 W/m2 infrared ‘back radiation’ from greenhouse gases, cooling results during both day and night.
http://solarcooking.org/research/McGuire-Jones.mht
Thanks Wikeroy: yes, I am on the same path as Johnson. On Bishop Hill I had a toe to toe fight with people who tried to trick me with a particular radiation calculation. What it came down to was that they used the textbook S-B equation, equal emissivity and absorptivity which you get from Kirchhoff’s Law of Radiation, to ‘prove’ back radiation exists but did not realise that Kirchhoff’s Law only applies at thermal equilibrium and the problem was far from it.
This is why the next step is to show that at TOA, extreme non-equilibrium means the emission towards the Earth’s surface is near zero, another nail in the back radiation coffin because you don’t need it to balance radiative transfer through the atmosphere.
It’s funny how it’s engineers and non Anglos who see through the scam!
Mydogsgotnonose:> Spartacus: the major problem with the Trenberth cartoon is the claim that heat transfer from the Earth’s surface to the atmosphere is [17+80+396=493 W/m^2] when in reality it’s [17+80+63=160 W/m^2], or an exaggeration by a factor of 3.08.
I completely agree with you! But there are more problems in that cartoon…
@tjfolkerts April 28, 2012 at 9:17am
You can see why I am less than enamoured of analogies. Might I suggest we discuss the alleged “greenhouse gas effect”, and not get into endless semantic arguments? I will of course be happy to attempt to point out the fallacies in your analogies if you wish, but this is digression for the sake of digression.
Now when you say ” . . .The sunlight penetrates to the “interior of the atmosphere” (ie the surface) and heats the atmosphere “from the inside” (like the furnace heats the house “from the inside”). . . .”, you can possibly remove extraneous words, and say “the sunlight penetrates to the surface.” I hope we agree on that. When the surface absorbs EMR (of any wavelength – energy is energy), the temperature of the surface and hence of the Earth, will rise. I trust you agree with this also.
But here’s the rub. When the surface “heats the atmosphere from the inside”, it does so by radiating EMR to the atmosphere. This process is exactly the opposite of absorbing EMR causing a rise in temperature, and results in a fall in the temperature of the surface. Wait for night in the desert or any other cloudless still night, and you will notice the temperature drops. The surface loses energy, the temperature drops.
Obviously, the atmosphere will absorb some of the radiation, and its temperature will rise. However, there are unavoidable energy losses when energy is transferred in this fashion. In any case, if you have ever looked at the stars, or across a room, you will notice that the atmosphere is remarkably transparent to a wide range of EMR wavelengths. So the atmosphere, of itself, allows a large amount of EMR to be lost from the surface to space without impediment.
If you examine the maximum surface temperature of the Moon when it is at the same distance from the Sun as the Earth, you will notice that it is much higher than anything that can be achieved at the Earth’s surface without artificial concentration of the incoming energy.
As I have said, anything other than a vacuum reduces, rather than enhances, the amount of EMR transferred between bodies.
So, once again, inducing a rise in temperature by reducing the amount of energy a body receives is nonsense. No ifs, buts or maybes.
Live well and prosper.
MIke Flynn.
Mike, I agree with most of what you say, especially:
Reducing the energy a body (in this case, the surface) receives will indeed reduce the temperature. If the surface could absorb all the sunlight, it would reach an effective black body temperature of ~ 279 K (warmer around noon; lower at night), radiating away 342 W/m^2 to match the incoming 342 W/m^2 of sunlight. Blocking some of the sun’s energy from reaching the surface (clouds reflecting light or air scattering light or ozone absorbing UV or …. ) will lower this effective temperature. The typical number is ~ 255 K (corresponding to 240 W/m^2), depending on exactly how much radiation you block from reaching the surface. Blocking incoming photons did cool the surface — no ifs, buts, or maybes.
But the converse is ALSO true. Reducing the energy a body LOSES will INCREASE the temperature. At an effective BB temp of 255 C, the surface will radiate ~ 240 W/m^2 to balance the income absorbed 240 W/m^2 of sunlight (the rest having been reflected away).
With no mechanism to block those IR photons, that 240 W/m^2 worth of photons will be shot straight out to space, never to return. If, however, there are GHGs that can absorb some of those IR photons, then the energy is NOT lost to space forever. Some of it can return when those GHG molecules emit energy back in random directions. When some of those photons return to the surface, they will get absorbed, adding energy to the surface that would not otherwise have been there.
Reducing the energy a body LOSES will INCREASE the temperature — no ifs, buts, or maybes.
Mydogsgotnonose says:
“PS I had a climate scientist argue that the reason why ‘back radiation’ did not heat up passive solar panels at night was because to overcome the thermodynamic limitation of the PMM, you need the external SW energy source, proof I think that they are going through intellectual hoops.”
Its good to hear that some people understand thermodynamics. This explanation is pretty much spot on.
A heat engine needs a hot reservoir and a cold reservoir, as any good engineer knows. The sun can be the hot reservoir, and the surface is the cold reservoir, with a net flow of heat from hot to cold and some work extracted.
What you seem to be expecting is that you could collect energy from a cold reservoir ( the cool atmosphere) and “focus it” to a hot reservoir ( the warmer surface) and run a heat engine from it. YOUR version would indeed be a violation of the 2nd Law of thermodynamics!
If you don’s see that your expectations are are wrong and the answer you got was right, then you SHOULD jump through a few more intellectual hoops until you understand the fundamental physics better.
“I still disagree with your argument. It does not matter if the reading is with different DMMs or the same DMM. The range for the first reading was 95.0 – 105.0 ohms and the second was 95.5 – 105.5 ohms. You simply cannot conclude that the difference in readings is 0.5 +/- 0.1 ohms, unless you are arguing that the precision of the DMM is +/- 0.1 ohms. ”
Lets make it an old-fashioned analog meter. Are you truly saying that you could watch the pointer moving 2% farther from zero, yet wonder if the resistance is increasing simply because the meter was only calibrated to +/- 5%?
Are you truly saying that you could watch a column of mercury climb 1% farther up a thin tube, yet wonder if the temperature is increasing simply because you don’t know if the starting position corresponded to 20 C or 25 C?
@ur momisugly Mydogsgotnonose
http://www.flir.com/cs/emea/en/view/?id=41964
Imaging Performance
IR resolution 640 x 480 pixels
Spectral range 7.5 – 13 µm
Image frequency 30 Hz
Focus Automatic or manual
Focal Plane Array (FPA) Uncoooled microbolometer
Measurement
Temperature range -40°C to +500°C (optional up to +2000°C)
Environmental specifications
Operating temperature range -15 °C to +50 °C
This thermal imaging camera will operate at +50C ambient This means the imigaging device (a micro bolometer array) is at at least 50C since it is uncooled.
How can it measure -40C when it is at 50C?
Easy
1 point the camera at a body at -40C and it will lose heat as a black body at 50C but It will gain heat from the cold body at -40C It will produce a voltage developed by the temperature difference set by -40C incoming 50C outgoing
2 point it at a surface at -10C and it will still lose heat as a BB of 50C but now it will receive radiation from the -10C body. It will now produce a voltage set by the -10C incoming and +50C outgoing
I.E. a colder body is warming the hotter body above the value that it would be when pointed at a body at 0K.
tjfolkerts 7:54 pm
Well, almost there.
You say “But the converse is ALSO true. Reducing the energy a body LOSES will INCREASE the temperature. ”
Not at all. Reducing the energy a body loses will slow the rate of temperature drop – that is all. That is how insulators work.
Bear with me. A body at a constant temperature is emitting precisely as much EMR as it is absorbing. As it emits radiation, the amount of energy left in the body drops. Unless the body absorbs enough energy to replace that which is lost, the temperature decreases – at a rate dependent on the energy flux differential.
Eventually after all available EM energy is emitted, then absolute zero is reached. Merely reducing the rate of energy loss will not increase the temperature. For that to occur, the body’s energy needs to increase. Even totally stopping energy loss – say for example, you had a perfect insulator surrounding the body, the temperature will not rise. At best, it will not fall.
So, a great big BUT. Once again, reducing the amount of radiation a body absorbs will not cause a temperature increase.
You are free to believe otherwise if you wish.
Live well and prosper.
Mike Flynn.
SergeiMK: a bolometer is similar to a pyrgeometer in that it measures the temperature difference between a collector in radiative equilibrium with the radiator and a controlled temperature reference
A negative temperature difference means the viewed material is colder.
tjfolkerts: like they you are clutching at straws!.
@- ozzieostrich says: April 28, 2012 at 11:51 pm
“Not at all. Reducing the energy a body loses will slow the rate of temperature drop – that is all. That is how insulators work.”
Have you never worn a coat, or put an extra blanket on the bed?!
Reducing the amount of energy lost from an object, while the the source of energy added remains constant results in the object warming.
The surface is warmed by the sun.
the rate it loses that energy depends on its temperature ~T^4. and the amount of energy any insulator returns to the surface. That is why it is warmer on a cloudy night, the cloud returns much more energy back to the surface than a clear sky.
But even a clear sky returns some energy back to the surface as can be measured with IR sensors. This reduces the rate of cooling so keeping the surface at a higher temperature than would be the case in a vacuum with no returning energy, as with the moon.
Those rejecting the role of the atmosphere as an insulator which modulates the gradient of energy emitted from surface to tropopause thereby increasing the surface temperature above that of a naked surface without an atmosphere are rejecting well established, experimentally confirmed physics. There are areas of the AGW theory that are uncertain, sensitivity and possible feedbacks that react to the warming. But the basic thermodynamics of energy flows in the atmosphere is old science, rejecting it is far more damaging to the credibility of the objectors than the science.
Try this for an equations and numerical explanation of surface warming from back radiation and the 2LoT. –
http://scienceofdoom.com/2011/02/07/understanding-atmospheric-radiation-and-the-%E2%80%9Cgreenhouse%E2%80%9D-effect-%E2%80%93-part-six-the-equations/
Izen,
Yes, I have worn a coat and have put an extra blanket on a bed. As insulators, they both reduce the rate of heat loss from my body, which then does not have to oxidise as much carbon to create sufficient heat to keep my temperature around 37C.
Have you ever wrapped a coat or a blanket around a corpse, (or a concrete block or similar, if you don’t have corpse handy?) No rise in temperature at all.
Now as to your statement which mentions the Moon. I assume you are unaware that surface temperatures on the Moon easily exceed anything that can be achieved on the Earth without concentrating incoming EMR. Likewise, the minimum temperatures on the Moon are lower than anything found on Earth.
This is because there is far more of the Sun’s energy per unit area hitting the Moon’s surface in accordance with maximal radiative energy transfer occurring in a vacuum. The same thing occurs in reverse when the surface of the Moon is radiating directly to space, without the insulating effect of an atmosphere to impede the transfer of EMR energy to outer space.
I am not sure where you obtained your information that the surface of the Moon is colder than that of the Earth when both are in direct sunlight, but I can assure you that your source is wrong.
As I have said a few times on this thread, the atmosphere acts as a relatively poor insulator. I should point out that insulators work both ways, if you like. They retard the rate of both heating and cooling (the insulator doesn’t know what it is insulating). For example, a rather good insulating device is a Dewar flask. It can keep hot things hot, and cold things cold. Amazing, eh? But even a Dewar flask cannot stop the remorseless radiative balancing that Nature dictates. Left long enough, both the cold and hot contents will be at exactly the same temperature, Dewar flask or no.
I agree that the basic thermodynamics of energy flows has been accepted science for a longish time. People who believe in the nonsensical notion that surrounding a body with no internal source of heat, (a corpse or concrete block, say) with an insulator will magically cause the temperature of the body to rise, are likely to believe almost anything.
Anyway,
Live well and prosper.
Mike Flynn.
tjfolkerts says:
April 28, 2012 at 8:21 pm
Lets make it an old-fashioned analog meter. Are you truly saying that you could watch the pointer moving 2% farther from zero, yet wonder if the resistance is increasing simply because the meter was only calibrated to +/- 5%?
Are you truly saying that you could watch a column of mercury climb 1% farther up a thin tube, yet wonder if the temperature is increasing simply because you don’t know if the starting position corresponded to 20 C or 25 C?
OK, it is clear now that you are confusing precision with accuracy.
There is a large degree of misunderstanding shown by many on what the cause and effect of the Earth’s so called greenhouse effect is. The misunderstanding on radiation heat transfer is only part of the problem. A few comments make some of the issues clear:
1) If the storage and transient effects are not large, incoming energy and outgoing energy are nearly equal. If the Earth is rapidly heating, or if the oceans are increasing total energy at a high enough level, the balance is off, but aveage temperature has been essentially constant for about a decade now, and ocean energy increase is fairly slow, so these are not major issues to a basic understanding of the greenhouse effect. For this case, solar energy heating the ground will be transferred by radiation, conduction, and convection, including evaporation and condensation of water. The heat transfer rate will not change at different surface temperatures. i.e., the greenhouse induced warmer Earth does not have a different rate of heat transfer than a planet with no greenhouse effect, but with the same albedo. There is no thermal insulation effect on heat transfer rate for the average steady state case.
2) When the so called greenhouse gases (they shoule be called selective optically absorbing gases or Tyndell gases or something else, as the effect is not at all like a greenhouse) absorb long wave thermal radiation, they will also radiate long wave thermal radiation. The only effect of this is to act as a thermal radiation insulator. However, due to 1), the conduction and convection heat transfer will adjust so that total energy transfer is the same as for no insulation. In the extreme case of the gases bening nearly perfect absorbers of the long wave energy, the radiation component of heat transfer from the surface goes to near zero, but conduction, convection and evaporation folloewd by condensation of water do all of the heat transfer. Talking about back radiation HEATING the surface is wrong. The back radiation would equal the up radiation, and net radiation would be zero. However, unlike with a blanket, the heat transfer would not be changed, since the other forms of heat transfer make up the difference.
3) The temperature gradient (average) is called the lapse rate, and only depends on the specific heat of the gas, gravity, and phase change of water vapor. When clouds are present, it is locally different, but I am referring to average value. The greenhouse gases do not change the lapse rate except for a minor change in average specific heat, and this is very small for Earth.
4) The absorbed solar energy has to eventually escape to space. This can only be done by radiation. There is a variation of altitudes where radiation escapes, but an average altitude can be found. The average temperature can be calculated from this average altitude from the outgoing energy level needed to balance incoming energy. The average temperature at that average altitude plus the average lapse rate times the average altitude of outgoing radiation result in the average surface temperature. That is the sole cause of the so called Earth greenhouse effect. Note that the only effect of the absorbing gases was to RAISE the altitude of outgoing radiation from the surface to a an average location up in the atmosphere. The greater the absorption, the higher you have to go before radiating to space.
Mike (ozzieostrich) says “Not at all. Reducing the energy a body loses will slow the rate of temperature drop – that is all. That is how insulators work.”
Sorry, no.
ΔQ/Δt = k A ΔT / Δx
Or ΔT = (ΔQ/Δt) (Δx) / (k A)
Assume (ΔQ/Δt), the rate of heat production, is constant (for example, running a furnace at a constant level in a house, or shining the sun at a constant rate onto the earth’s surface). Assume the temperature on the “outside” is constant (eg 0C outside the house or 0K outside the earth). Assume the area doesn’t change (no additions to the house; the earth stays the same size).
The difference in temperature between outside an inside, ΔT, then depends on thermal conductivity, k, and thickness of the insulation, Δx. The temperature difference increases (ie the “inside” gets warmer) if either
1) the thickness increase.
2) the thermal conductivity decrease.
So if we increase the insulation (by either of these two methods), the “inside” gets warmer.
THAT is how insulation works!
Having said that, the ability of actual insulation to slow the loss of energy is a different mechanism from GHGs slowing the loss of energy. But the end result in either case is a “warmer interior” while keeping the energy loss at the exterior the same.
“OK, it is clear now that you are confusing precision with accuracy.”
No, I do know the difference. Precision is typically considered how many digits you can read (or some similar measurement), which is different from linearity (and different from accuracy). All three bits of information are important when interpreting a measured value.
Put another way, measurements of DIFFERENCES can be MUCH more accurate (and just a precise) compared to measuring each value separately and subtracting AFTER you have already thrown away information you have about the linearity and repeatability of the meter.
Specifically, if I knew that my instrument was perfectly linear but only accurate to +/- 10%, then an increase from 100.00 +/- 10% to 101.00 +/- 10 % would be an increase of 1.00 +/- 10 %.
Curved Insulation Pipe/Earth Analogy
It would seem at first that the thicker the insulation the less the total heat loss. This is always true for flat insulation but not for curved insulation. For instance considering a pipe with successive layers of cylindrical insulation, as the thickness of the insulation is increased, the surface area from which heat may be removed by air increases and the total heat loss may also increase if the area increases more rapidly than the resistance.
In the case of the pipe the maximum heat loss from its surface occurs when the critical radius from pipe centre equals the ratio of the thermal conductivity of the insulation to the surface coefficient of heat transfer. Perhaps Leonard Weinstein was alluding to this with his statement that for Earth – ‘the average temperature can be calculated from this average altitude from the outgoing energy level needed to balance incoming energy. The average temperature at that average altitude plus the average lapse rate times the average altitude of outgoing radiation result in the average surface temperature. That is the sole cause of the so called Earth greenhouse effect. Note that the only effect of the absorbing gases was to RAISE the altitude of outgoing radiation from the surface to a an average location up in the atmosphere. The greater the absorption, the higher you have to go before radiating to space.’
tjfolkerts says:
April 29, 2012 at 7:40 am
No! Precision is defined as the repeatability of a measurement. The number of digits that you can read from the instrument is irrelevant.
Again, no! Differences will always be less precise than the individual measurements. This fact is commonly referred to as subtractive cancellation and the magnitude can be readily calculated by propagating the errors. As far as the statement “thrown away information… about linearity and repeatability…,” I have absolutely no idea what this means. The general procedure for calibration of an instrument, where one is only interested in relative changes, requires establishment of both repeatability (often referred to as system suitability) and linearity (or establishment of another suitable response curve). In addition, it is critical to establish the LOQ (limit of quantitation) and LOD (limit of detection), which are based on the signal-to-noise ratio. All of these data are vital to interpretation of any measured quantity and to rationally determine whether that measured quantity is meaningful. For time dependent studies, such as those which would be required for establishment of a temperature trend, you also need to establish reproducibility of the instrument, which is defined as the precision obtained from measurements collected on the same piece of equipment on different days and by different operators. Note: reproducibility will always be worse than repeatability. If you are really interested in educating yourself on the subject, I suggest you study the cGLP/cGMP requirements that establish the best practices for collecting analytical data of the highest quality.
I do not understand why you keep using “+/-” to refer to accuracy. If the instrument is inaccurate, it will be off either by a positive deviation or a negative deviation, but not both. If it can be off by either a positive or negative deviation (i.e. +/-), then you are referring to the precision of the instrument.
tjfolkerts says:
“So if we increase the insulation (by either of these two methods), the “inside” gets warmer.”
This use of language is not accidental.
The more thoughtful supporters of IPCC science have enough sense as to not say ‘heat’ the inside.
The less careful supporters like Chris Colose and ‘Eli ‘ Halpern are less inhibited.
tjfolkerts knows fine well that insulation does not heat anything.
It can however reduce the heat transfer to the colder side.
The public are being asked to take a massive dislocation of their economy and standard of living.
The least they should expect is honest answers from their educated professionals who should know better.