Paper finds a decrease of IR radiation from greenhouse gases over past 14 years, contradicts expected increase – cloudiness blamed for difference.
A paper published in the Journal of Climate finds from 800,000 observations a significant decrease in longwave infrared radiation from increasing greenhouse gases over the 14 year period 1996-2010 in the US Great Plains. CO2 levels increased ~7% over this period and according to AGW theory, downwelling IR should have instead increased over this period.
According to the authors,
“The AERI data record demonstrates that the downwelling infrared radiance is decreasing over this 14-yr period in the winter, summer, and autumn seasons but it is increasing in the spring; these trends are statistically significant and are primarily due to long-term change in the cloudiness above the site.”
The findings contradict the main tenet of AGW theory which states increasing greenhouse gases including the primary greenhouse gas water vapor and clouds will cause an increase of downwelling longwave infrared “back-radiation.”
The paper also finds a negative trend in precipitable water vapor, as do other global datasets, again the opposite of predictions of AGW theory that warming allegedly from CO2 will increase precipitable water vapor in the atmosphere to allegedly amplify warming by 3-5 times. Is the unexpected decrease in water vapor the cause of the decrease in downwelling IR?
Global datasets also show an increase of outgoing longwave IR radiation to space from greenhouse gases over the past 62 years, again in contradiction to the predictions of AGW theory.
Gero, P. Jonathan, David D. Turner, 2011: Long-Term Trends in Downwelling Spectral Infrared Radiance over the U.S. Southern Great Plains. J. Climate, 24, 4831–4843.
doi: http://dx.doi.org/10.1175/2011JCLI4210.1
Long-Term Trends in Downwelling Spectral Infrared Radiance over the U.S. Southern Great Plains
P. Jonathan Gero
Space Science and Engineering Center, University of Wisconsin—Madison, Madison, Wisconsin
David D. Turner
NOAA/National Severe Storms Laboratory, Norman, Oklahoma, and Department of Atmospheric and Oceanic Sciences, University of Wisconsin—Madison, Madison, Wisconsin
Abstract
A trend analysis was applied to a 14-yr time series of downwelling spectral infrared radiance observations from the Atmospheric Emitted Radiance Interferometer (AERI) located at the Atmospheric Radiation Measurement Program (ARM) site in the U.S. Southern Great Plains. The highly accurate calibration of the AERI instrument, performed every 10 min, ensures that any statistically significant trend in the observed data over this time can be attributed to changes in the atmospheric properties and composition, and not to changes in the sensitivity or responsivity of the instrument. The measured infrared spectra, numbering more than 800 000, were classified as clear-sky, thin cloud, and thick cloud scenes using a neural network method. The AERI data record demonstrates that the downwelling infrared radiance is decreasing over this 14-yr period in the winter, summer, and autumn seasons but it is increasing in the spring; these trends are statistically significant and are primarily due to long-term change in the cloudiness above the site. The AERI data also show many statistically significant trends on annual, seasonal, and diurnal time scales, with different trend signatures identified in the separate scene classifications. Given the decadal time span of the dataset, effects from natural variability should be considered in drawing broader conclusions. Nevertheless, this dataset has high value owing to the ability to infer possible mechanisms for any trends from the observations themselves and to test the performance of climate models.
via the Hockeyschtick with thanks
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Pamela The phrase ” natural intrinsic variability” really means ” we don’t know why climate changes.”
One of my main points is that you don’t necessarily have to know or even understand the processes involved in order to make useful predictions. Just observe the existing periodicities in the temperature data and project them forwards. As to the sun there ,are obvious correlations between solar minima as seen in the10Be data and temperature minima see Figs 10 C and D and Fig11 at
http://climatesense-norpag.blogspot.com/2014/07/climate-forecasting-methods-and-cooling.html
In the same post I say
“NOTE!! The connection between solar “activity” and climate is poorly understood and highly controversial. Solar “activity” encompasses changes in solar magnetic field strength, IMF, CRF, TSI, EUV, solar wind density and velocity, CMEs, proton events etc. The idea of using the neutron count and the 10Be record as the most useful proxy for changing solar activity and temperature forecasting is agnostic as to the physical mechanisms involved.
Having said that, however, it is reasonable to suggest that the three main solar activity related climate drivers are:
a) the changing GCR flux – via the changes in cloud cover and natural aerosols (optical depth)
b) the changing EUV radiation – top down effects via the Ozone layer
c) the changing TSI – especially on millennial and centennial scales.
The effect on climate of the combination of these solar drivers will vary non-linearly depending on the particular phases of the eccentricity, obliquity and precession orbital cycles at any particular time.
Of particular interest is whether the perihelion of the precession falls in the northern or southern summer at times of higher or lower obliquity.”
It is perfectly possible to understand well enough to forecast what is going to happen in a complex system which can’t be calculated numerically because of the number of variables involved. See Section 1 of the link.
Calculations of cloud albedo which can then be used to determine how much energy is being absorbed by the ocean in the equatorial band. It is therefore possible to determine how much recharge is happening. My speculation is that this variation could explain the warming and cooling trends of oceans, which then translate to warming or cooling trends over land through the process of oceanic evaporation or absorption of solar energy.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCQQFjAA&url=https%3A%2F%2Fearth.esa.int%2Finstruments%2Fmeris%2Fpdf%2Fatbd_2_01.pdf&ei=2PXiU_v6AdWEyQT0v4KgDQ&usg=AFQjCNFnIOlFgmacY8W5cu1sOVM4UMFeIw&sig2=ihfvRbBEjIeFZxqvu1G3lg&bvm=bv.72676100,d.aWw
One more thought on intrinsic factors and drivers. The higher the albedo (reflectivity to shortwave IR solar energy) of clouds the greater amount of DWLWIR radiation. Which means that while the ocean is actually cooling through evaporation, the air will warm up a bit due to the additional LWIR that normally would escape (since it is re-radiated in all directions). Yet this kind of warming cannot reverse the oceanic evaporative cooling that is happening. Longwave radiation has a dickens of a time penetrating the ocean surface skin. It is mostly immediately evaporated off.
sturgishooper says, August 6, 2014 at 4:58 pm:
“Please correct me if wrong, but IIRC thermodynamics and thermochemistry, heat is the energy transferred from a warmer to a cooler object. Saying warm and cold leads to the murky intersections of temperature, heat and energy. Again IIRC, temperature is proportional to the average energy per atom or molecule in an object or mass measured, while heat is proportional to the total energy of all atoms in the object or mass.”
Yes. ‘Heat’ is that first thing. Energy transferred from a warmer to a cooler object. And no. It’s not that second thing. Proportional to the total energy of all atoms in the object or mass. Heat has got nothing to do with the temperature of an object. It has to do with the temperature difference between an object and its surroundings (and/or a nearby object). The temperature of an object is proportional to its ‘internal energy’. Heat is not something that can be and is contained within an object. It moves between regions of different temperatures, because of the difference in temperatures. And in nature it ONLY and ALWAYS moves from hot to cold.
The climate establishment thrives on this confusion. Just look at Trick and David M. Hoffer here. And Science of Doom. Take a look at this utterly confused statement by Hoffer: “It [‘atmospheric back radiation’] isn’t heat or work, it is an energy flux. We can measure it, we can measure the heat it creates and we can measure the work it does.” If everyone simply understood and stuck to the real physical definition of ‘heat’, took one step back and let it sink in, they would see at once how nonsensical and incongruous this statement really is.
These people simply wouldn’t and couldn’t have a case to build. Because everyone would understand, intuitively, that EM energy from a cooler atmosphere to a warmer surface is not an actual (detectable) transfer of energy. It is a potential transfer of energy based on radiant emittances, if those emittances were not faced with other and similar emittances inside one integrated, indivisible energy (radiation) field/exchange where ‘energy’ moves in all directions, but where the actual transfer of energy, the ‘heat’, the net sum of them all, moves in one direction only. Like bulk air from high to low pressure. Like an electric currrent from high to low voltage. Always from high to low potential.
People need to understand this. It’s how things work. Actually work. It’s what we see, observe, feel, sense. They need to comprehend it to be able to wake up from the climate ‘science’-induced slumber we all seem to be infused by.
“Is this understanding of thermodynamics outdated?”
Of course not. Thermodynamics can never be outdated. It describes reality. Natural processes. It just is. The concept, the physical phenomenon of heat doesn’t change even if we find out about electromagnetic radiation on a microscopic level. The laws of thermodynamics still stand. They are still absolute. There are no concessions granted. Not to conductive transfer. Not to radiative transfer. The climate confusion brigade wants to pretend, wants to argue of course that it’s somehow outdated, that now we know more so now all of a sudden for some reason the concept no longer holds. Er, why would it change a thing? The effects of natural processes don’t change even as we find out more about the processes themselves, the mechanisms behind them. The effect of a heat transfer remains the same as always. Thus ‘heat’ remains the same as always.
“If so, I hope it’s not more corruption of science to help explain the magical transfer of heat from the atmosphere to the oceanic depths, where it can’t be measured or the temperature of those layers be taken, without having first to pass through the upper layers of seawater, with their various halo- and thermoclines.”
Exactly. If we all simply knew what ‘heat’ is and how it moves, this argument would and could not see the light of day, much less gain any traction. Everyone would see immediately that a cool atmosphere can not be responsible for a warming ocean if the atmosphere and then the surface didn’t warm first and more.
F. Ross says, August 6, 2014 at 5:04 pm:
“How does one body “know” or “sense” that it is somehow at a higher (lower) temperature than the other body?”
How does water “know” or “sense” that it should move down a waterfall, not up? How does air “know” or “sense” that it should move from a higher to a lower pressure area? How does an electric current “know” or “sense” that it should move from a higher to a lower voltage?
Gradients. Potential gradients.
Kristian et al.
Note that energy is not necessarily heat.
Energy includes photons moving at the speed of light which does not generate heat until it interacts with matter, latent heat of phase changes from solid to liquid to gas and back again all of which involve disappearance and reappearance of heat between sensible and latent heat and work done with or against gravity which converts heat to and from gravitational potential energy (GPE) with GPE not being sensible heat.
Radiative theory ignores those transitions of energy to and from sensible heat yet it is those transitions that account for the increase in surface temperature above the S-B expectation which is a radiative only equation.
Energy which is engaged in conduction and convection within an atmosphere is not available for radiation to space at the same time yet it nonetheless gives rise to an enhancement of surface temperature.
That ‘extra’ 33C arises simply because the surface temperature enhancement is required for the conductive / convective energy exchange which keeps the mass of an atmosphere suspended off the surface. That ‘extra’ 33C cannot be radiated to space at the same time as it is being used for the conductive / convective exchange.
The same unit of energy cannot be in two places at once or carrying out two functions at once.
At the surface, all available energy is in the form of sensible heat but above the surface a portion of the radiative energy which would otherwise escape to space becomes locked into a non sensible form (GPE) as it supports the weight of the atmosphere and constantly recirculates in a net zero adiabatic energy exchange through conduction and convection for as long as there is a gaseous atmosphere.
GHGs simply allow some of the energy locked into the conductive / convective exchange to radiatively leak to space from within the atmosphere which then means that less energy circulates back to the surface as sensible heat than was removed from the surface in the first place.
That weakens the adiabatic exchange exactly as much as the amount of radiation leaked to space.
DWIR radiating down to the ground is the same as the energy leaked to space by UWIR because GHGs radiate in all directions equally and so that extra DWIR compensates for the reduction in strength of the adiabatic exchange.
Surface temperature stays the same but radiation to space shifts slightly from surface to space to atmosphere to space with the total amount of radiation lost to space still equalling the amount coming in from space.
Hence long term retention of atmospheres regardless of GHG quantities.
“””””….Alan Robertson says:
August 5, 2014 at 9:45 pm
Wayne Delbeke says:
August 5, 2014 at 9:37 pm
*Usage note
The often heard but misleading “rule” that a sentence should not end with a preposition is transferred from Latin, where it is an accurate description of practice. But English grammar is different from Latin grammar, and the rule does not fit English. In speech, the final preposition is normal and idiomatic, especially in questions: What are we waiting for?
_______________
Are you saying that those who insist on not ending a sentence with a preposition are up screwing?…..”””””
Well I’m rather adamant about this.
A preposition is not a proper word to end a sentence with.
Increase in outgoing IR is consistent with global warming. Radiative flux is directly proportional to the fourth power of temperature.
Decrease in downward longwave radiation (DLR) in past 14 years would imply decrease in greenhouse gases in atmosphere. US decreased its CO2 emissions from 6 billion tons to 5 billion tons in last 10 years. While US grains production increased 294 million tons to 400 million tons (2002-2012). Less CO2 emissions and more crops absorbing CO2 in the Great Plains. Slight decrease in atmospheric CO2 in the Great Plains? Surprise, surprise.
Kristian,
“How does water “know” or “sense” that it should move down a waterfall, not up? How does air “know” or “sense” that it should move from a higher to a lower pressure area? How does an electric current “know” or “sense” that it should move from a higher to a lower voltage?
Gradients. Potential gradients.”
Or you could say that the entropy increases. In simple terms air moves from a higher pressure to a lower pressure because when the molecules at higher pressure (moving at higher speed) collide with molecules at lower pressure (moving at lower speed), the result of the collision is that momentum is exchanged such that the slower moving molecules speed up and the faster moving molecules slow down. This is no more than the application of probability. The same goes for the transfer of heat.
Stephen Wilde says, August 6, 2014 at 11:30 pm:
“Kristian et al.
Note that energy is not necessarily heat.
Energy includes photons moving at the speed of light which does not generate heat until it interacts with matter (…)”
Once again: ‘Heat’ is not something contained inside a body. ‘Heat’ is not something that is ‘generated’ upon absorption of energy. This is one of the deep-rooted misunderstandings and misapplications of the physical term.
‘Heat’ is what’s being absorbed.
When ‘heat’ is absorbed by a body, then its ‘internal energy’ and hence its ‘temperature’ increases. That is the correct way of putting it. To avoid confusion. ‘Heat’ in physics is only the energy passed from hot to cold as a result of the temperature difference, Stephen.
I’ll reiterate the quote from hyperphysics, explaining the difference by rephrasing the words of physicist Mark Zemansky:
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heat.html
“Zemansky points to the First Law of Thermodynamics as a clarifying relationship. The First Law [ΔU = Q – W] identifies both heat [Q] and work [Q] as methods of energy transfer which can bring about a change in the internal energy [U] of a system. After that, neither the words work or heat have any usefulness in describing the final state of the sytem – we can speak only of the internal energy of the system.”
Vince Causey says, August 7, 2014 at 3:13 am:
True. Thanks.
Kristian says, August 7, 2014 at 4:30 am:
Sorry, that should be “… work [W] <em<…"
So man-made global warming theory isn’t true then is it?
Steven Mosher says:
One site.
This is the expected rebuttal.
Nick Stokes says:
But it doesn’t contradict any main tenets. It states explicitly that the result is due to a change in cloudiness. And since they measured cloudiness, that is not speculation.
But you cannot ignore clouds, like the models and all the cant do.
Clouds are obviously part of the climate
george e. smith says:
What are we waiting for?
That should be For what are we waiting? 😛
Sturgis 4:58pm: “…heat is the energy transferred from a warmer to a cooler object…..Is this understanding of thermodynamics outdated?”
Yes. This implies heat was over there in the warmer object and after being transferred (poured?) is now over here in the cooler object. So many people have talked and continue to talk about heat as if it were a substance that by hook or crook a corporeal form for heat must be invented in order to save appearances. Try this:
Net energy is transferred from a warmer to cooler object. Zeroth & 2LOT laws are macro.
Energy was over there and it is now over here. No need to invoke a confusing corporeal form for heat to be poured out of the higher temperature object; heat as a substance doesn’t exist. Invoking heat’s paranormal existence becomes a major source of befuddlement. Sometimes authors use “heat” correctly, many times not – the best solution is simply not to use the term. This campaign started as early as the ’50s, it is still unfinished work.
“..temperature is proportional to the average energy per atom or molecule…”
Averages are dissed on another thread. Research Maxwell-Boltzmann distribution of molecular speeds which contains some added clarifying explanation for the mean distribution of an object’s constituent particle energies in a non-gravity field. This M-B distribution allows for a higher energy molecule in the lower temperature object to transfer energy to a lower energy molecule in the higher temperature object at times. Cold can flow to hot in this manner as universe entropy is increased; the net energy flow of all the constituent particles will be toward the lower temperature object to increase universe entropy by macro 2LOT.
This issue has legs. For critical discussions & earlier ref.s of the confusing and contradictory uses of “heat” term, see Zemansky 1970, “Use & Misuse of the word “Heat” in Teaching Physics”, The Physics Teacher, Vol. 8, pp. 295-300; Tribus 1968: Generalizing the meaning of Heat”, Intl. Jnl. of Heat and Mass Transfer, Vol 11, pp. 9-14; Gagglioli 1969: More on Generalizing the Definitions of “heat” and “entropy”, Intl. Jnl. of Heat and Mass Transfer, Vol. 12, pp 656-60.
Bohren 2006: “there is no such thing as “heat radiation” in the sense of a special kind of radiation emitted only by “heated bodies”, “Radiant heat” is a “meaningless term” is from Yves Le Grand, 1957: Light, Colour, and Vision, John Wiley & Sons, p. 4.
Again, to parse Kristian comments et.al., especially OHC papers, substitute “energy” for “heat” term to add clarity to anyone’s reading comprehension. Both have units of joules.
If clouds cannot be modeled, how can cloudiness be blamed for the contradictions? There’s always a logical-fallacy justification involved when invented models don’t go to plan.
Never an apology.Funny, that.
sturgishooper says:
August 6, 2014 at 3:08 pm
“. . . climate can be . . is . . regional”
I agree with you. Climate can refer to regional weather when the time scale is decadal or centennial or even millenial. Did you miss my main points completely? The point about drawing global conclusions from regional data? The point about climate refering to long time scales, vs weather being local and short term? In attempting to correct me were you also disagreeing with those points?
Again, my main point was – – -> Unless you suspend the laws of physics which regulate, and place limits on, the transport to/from, and exchange of, energy between the atmospheric gasses, the liquids in the oceans, and the solids and liquids on land, then there can be no hidden positive feedback to cause a runaway catastrophic result caused by a 0.4 degree change in temperature over a century! The evidence for this conclusion is simple: If the positive feedback that has been proposed actually existed then surely it would manifest itself when there is a routine daily change of 20 degrees, and an annual change of 50 degrees. Both of these swings in the variable “temperature” are routinely observed, yet neither “extreme” ever causes “thermaggedon”.
My point was in defense of this article drawing what amounted to “global” conclusions from a long term historical look at very “regional” data. Steven Mosher seemed to object to these conclusions with his two word observation “One site.” The CAGW scientologists seem to me to be very biased in selecting which data can be used to draw “climate” change conclusions. For instance, temperature must be measured at as many sites as possible, then filtered, skimmed, homogenized, pasteurized . . . oh wait, thats what you do to milk . . . well at least filtered and homogenized. While CO2 data is righteously collected at the top of an active volcano above the clouds at only one location and this data is widely cited to be representative of the “global” value as the “ACTUAL” change in global CO2 concentration? Why aren’t CO2 values collected at each of the same sites as temperature along with the largest “carrier” of energy – water vapor? If this CO2 value is so righteous, why not look at the temperature and water vapor trends at that same site? Is it perhaps because the long term changes at that site show no causitive correlation between CO2 and temp? Is there even measureable humidity at the top of Mauna Loa?
My point in defense of drawing global conclusions from a historical look at data from one site, is that, if 1) a similar conclusions can be drawn from one site’s measure of the change in CO2 over decades/centuries, and 2) “climate” is the accumulated broad time-scale look at weather, then the conclusions regarding global impact of CO2 on temperature that are drawn in this paper are equally valid.
For the record, let me state my humble opinions regarding the “CO2 is evil” debate:
1) CO2 does contribute to keeping the planet warmer than for example a gas free planet, However, CO2’s contribution has just about reached it’s limit and changes at this point are pointlessly insignificant. Water is the dominant thermal governor on the blue planet. CO2 can not even come close to water’s impact because it never changes phase.
2) CO2 is necessary for green plant life,
3) Man has been working hard to rebalance the distribution of carbon from solid phase to gaseous to assist in “greening” the planet and helping out plant life,
4) In their order of value to mankind I offer my hierarchy of needs: God’s mercy, Fellow man, Energy, Food (ie green plants, and animals that eat them), Shelter, Warmth. . . . I’d put “Love” on the list as well, but I can’t decide where. We need to keep our priorities straight. The planet isn’t in trouble because of CO2!
5) Championing the elimination of CO2, or declaring a “war on climate change”, ahead of any of these, to me is a sure sign of chicken-little-the-sky-is-falling mental illness.
DonV says:
August 7, 2014 at 10:56 am
I didn’t miss your point about global. I agree with it.
One wonders if Kristian believes that Stefan-Boltzmann Law is correct.
Trick says:
August 7, 2014 at 6:30 am
Sturgis 4:58pm: “…heat is the energy transferred from a warmer to a cooler object…..Is this understanding of thermodynamics outdated?”
Gents, refrigeration will ‘move “heat” from a cooler object to a warmer object’ depending on how you define your system. Of course work has to be done on the heat transfer medium to take “heat” out of your ice cream and exhaust it into the warmer kitchen. I’m sure Trick knows his thermodynamics but it is the ‘little-bit-of-knowledge-is -a-dangerous-thing’ that gives Sturgis and many others the simplistic notion of what heat is. It has become a major incorrect argument among a group of them that insist that the pressure on the bottom of the atmosphere causes the heating of the atmosphere (another misguided understanding of the gas laws).
“It has become a major incorrect argument among a group of them that insist that the pressure on the bottom of the atmosphere causes the heating of the atmosphere.
Pressure on the bottom of an atmosphere increases density.
The higher the densty the greater the proportion of radiative energy passing through the system that can be conducted from the solid surface to the mass of the atmosphere.
Uneven surface heating then causes density differentials in the horizontal plane and convection ensues. That happens even if there are no GHGs at all.
Convection takes conducted energy in the form of heat upwards away from the surface and converts it to gravitational potential energy which does not radiate and is not sensible heat.
What goes up must come down (unless radiated to space from within the atmosphere) so the descent reconverts GPE to heat in the air above the surface.
That warmth returns to the surface but cannot be radiated to space because it is removed upwards again in the next convective ascent.
Meanwhile the surface becomes warmer than SB because the surface is ‘handling’ both new energy from the sun and the energy exchange needed to sustain convective overturning.
The net consequence is:
i) The radiative exchange with space is in balance
ii) The adiabatic exchange between surface and atmosphere is in balance
iii) Surface temperature is higher than S-B predicts
iv) The system remains stable in the long term because increased radiative energy to space from within the atmosphere in i) is always offset by reduced energy returned to the surface on descent in ii) and vice versa.
Simple really.
Gary Pearse says:
August 7, 2014 at 1:41 pm
“It has become a major incorrect argument among a group of them that insist that the pressure on the bottom of the atmosphere causes the heating of the atmosphere (another misguided understanding of the gas laws).”
No, it is the heat of compression as a parcel moves from its max altitude back to the surface that causes the heating. Classical thermodynamics you should have learned in high school.
Gary Pearse says:
August 7, 2014 at 1:41 pm
My little bit of thermodynamical understanding seems deeper than your even shallower knowledge.
Gary Pearse 1:41pm opens the Pandora Box.
Stephen 2:31pm – Your bombshell imagination takes on even more than the top post Great Plains, it goes global & remains unfettered by atm. science. Being an equal opportunity parsing specialist since “heat” no longer is generally considered to exist in nature: “Convection takes conducted energy in the form of heat upwards away from the surface and converts it to gravitational potential energy which does not radiate and is not sensible heat.”
becomes
1) Convection takes conducted energy in the form of energy upwards away from the surface and converts it to gravitational potential energy which does not radiate and is not sensible energy.
OR
2) Convection takes conducted joules in the form of joules upwards away from the surface and converts it to gravitational potential joules which does not radiate and is not sensible joules.
Neither 1) or 2) can make any sense just like the original. I agree it is nonsense to state joules radiate. Would be same as “radiant heat” which was shown to be nonsense in 1957.
“Meanwhile the surface becomes warmer than SB…Surface temperature is higher than S-B predicts.”
Matter meeting the Planck assumptions anywhere at any time at any frequency interval at any temperature has never been observed “warmer than S-B” or “higher than S-B predicts”. The Planck distribution has been observed to hold in all frequency intervals, in all applicable observations (meaning no diffraction complications & macro positive radius objects) which is why it earned law status. Do not go outside without proper insulating jacket in Earth polar regions after consulting the latest global surface Tmean report.
******
I’m convinced Stephen’s “Simple really” and pochas 2:40pm bombshell explanations would allow me to turn off my furnace & stay warm as needed this winter if only they were possible in science.
pochas 2:40pm – What you describe is the defn. of potential temperature – an adiabatic process so no energy is added (or subtracted) to the surroundings of the parcel. But sure, I’d like to use your explanation to warm the nearby surface instead of my furnace this NH winter.