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The theory says that the energy absorbed by carbon dioxide is returned to the Earth's surface and raises its temperature.
But, the surface has mass, earth, soil, rocks, etc., and this needs energy if the temperature is to increase.
Remember, Energy = mass * specific heat * increase in temperature

Why is this point never mentioned in the theory? It seems to have been completely ignored.
Eddie Banner

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    $\begingroup$ What research have you done to suggest that climate models do not take this into account? A cursory literature search would reveal that GCMs include land surface components. $\endgroup$
    – Andy M
    Commented Mar 10, 2022 at 16:59
  • $\begingroup$ I have searched everywhere I could. I should be very grateful if you would be kind enough to provide me with references dealing with this point. Certainly, the IPCC theory is correctly based upon the idea of more carbon dioxide absorbing more of the energy radiated from Earth's surface. This energy is returned to the surface and increases the surface temperature (S-B). BUT, there is no Physics explanation of HOW this can. The surface consists of real substances which have mass, and simply by school Physics this needs the energy to raise its temperature. So there is none left to emit. $\endgroup$ Commented Mar 10, 2022 at 19:21
  • $\begingroup$ Have you looked into any textbook of climatology? Heat capacity of land and ocean is one of the most fundamental factors that are considered already in basic climatology, and of course they are parameterized in climate models. $\endgroup$
    – uUnwY
    Commented Mar 10, 2022 at 23:57
  • $\begingroup$ @EddieBanner her is one answer to your question earthobservatory.nasa.gov/features/EnergyBalance please do a minimum of research before asking a question,a more focused question will most likely give you better answers. $\endgroup$ Commented Mar 11, 2022 at 8:26
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    $\begingroup$ It's much akin... to a greenhouse itself. Or sort of like a blanket (except instead of just trapping energy inside, it lets in energy, then hinders its escape). Back to the gardening greenhouse... plants, pots, soil in it all have mass... physics teaches extra energy is required to raise the temperature. This extra energy comes from letting sunlight in and not letting it escape as easily. So it warms. Greenhouse glass/CO2 both hinder some of the radiation escape by absorbing, and thereby keeping it in the system longer (as some of that energy is returned down to the greenhouse and its objects) $\endgroup$ Commented Mar 11, 2022 at 14:38

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You’re possibly thinking of the steady state descriptions, as shown in something like the Trenberth diagram below. These are steady state descriptions of energy flows rather than energy stores, in which the system has already accumulated energy in various components and their states (e.g., temperatures) have already adjusted to remove any imbalance in energy flow through the system. Even in balance energy continues to flow through the whole system, with input from the sun balanced by output from thermal emission to space at the system boundary.

enter image description here

By NASA - https://web.archive.org/web/20140421050855/http://science-edu.larc.nasa.gov/energy_budget/ quoting Loeb et al., J. Clim 2009 & Trenberth et al, BAMS 2009, Public Domain, https://commons.wikimedia.org/w/index.php?curid=32285340

If we changed something about that system, such as increasing atmospheric CO2, and recalculated the energy flows only, we would find that those flows no longer balance. Each component would have a net gain or loss of energy. At this point we could re-diagnose the states (e.g., atmosphere and surface temperatures) that would bring this system back into balance.

Note there’s no component of time in this description, this is just diagnosing the initial and final states of the system in response to a given change. Under this model we don’t need to know the details of what the surface is made of, we’re just describing it as something that radiates like a black body with a particular emissivity. But if we want to know how the system transitions between those two balance states then, yes, we will need to know the heat capacities of the various components. Components with larger heat capacities will take longer to transition and accumulate more energy for a given level of energy imbalance than components with smaller heat capacities.

Why is this point never mentioned in the theory? It seems to have been completely ignored.

Just taking one example climate model land surface scheme, http://doi.org/10.5194/gmd-4-677-2011, the surface heat capacity it literally the first term of the first equation in that paper.

Similarly, the latest IPCC report (and many of the previous ones, and the references therein) has lots of analysis of this aspect, e.g., Fig TS.13:

enter image description here

IPCC AR6 (2021), Technical Summary (pdf), Figure TS.13 (page TS-150).

Where does the extra energy come from? It cannot be created to suit. It can only come from the energy absorbed by the extra CO2

Ah no, this maybe where your confusion lies. The energy comes from the sun, which is a continual external input of energy to the Earth system. An increase in greenhouse gas concentration causes some of that energy to accumulate in the system, changing the system state, until the state has changed to the point that input and output are back in balance.

Energy is required to increase the temperature of the surface, and more energy is required if any is to be radiated. This can only be funded by the extra energy absorbed by the extra CO2 The extra energy cannot be provided by the Sun, because its supply to the surface was already in balance with output before the addition of CO2.

Well, specifically, increasing the greenhouse gas concentration reduces the atmospheric transmittance to longwave radiation, which reduces the amount of energy leaving the atmosphere to space and increases the energy content and temperature of the atmosphere. The warmer atmosphere emits more longwave radiation both to space (thereby weakening the initial top-of-atmosphere imbalance) and to the surface. The latter changes the surface energy budget through the downwelling longwave term, reducing the net loss of energy from the surface by longwave exchange and increasing in the energy content and temperature of the surface. But while the "back radiation" may be the route through which surface temperature increases, the sun is the origin of all the energy flowing through the diagram at the top.

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  • $\begingroup$ Thank you for your reply, Deditos, and for the reference to the paper by M J Best et al dealing with the JULES model. gmd.copernicus.org/articles/4/677/2011/gmd-4-677-2011.pdf This paper does, indeed, mention surface heat capacity on page 680. It describes three different attempts to make the JULES model agree with actual data. The first two tries assumed a value of ZERO for the surface heat capacity; the third attempt gave improved agreement, but the value, sadly, was not given. So, this paper agrees that the capacity is real, but not zero. Out of space!! $\endgroup$ Commented Mar 11, 2022 at 19:21
  • $\begingroup$ Continued. Why is space so limited? Therefore, a proper treatment the surface heat capacity must be included in any sensible theory. Energy is required to increase the temperature of the surface, and more energy is required if any is to be radiated. This can only be funded by the extra energy absorbed by the extra CO2 The extra energy cannot be provided by the Sun, because its supply to the surface was already in balance with output before the addition of CO2. $\endgroup$ Commented Mar 11, 2022 at 19:32
  • $\begingroup$ Hi, Deditos, You say "An increase in greenhouse gas concentration causes some of that energy to accumulate in the system". This can only be in the surface, and the supply to the surface has to be shared, somehow, btween actually heating the surface and supplying energy to be radiated. This is simply an adaptation of Kirhhof'Law. $\endgroup$ Commented Mar 11, 2022 at 19:38
  • $\begingroup$ I have asked two Tyndall Centres, one at Manchester and one at East Anglia, for a Physics explanation of HOW the extra energy absorbed by extra CO2 from the output radiated from the Earth's surface can cause an increase in the land surface temperature. I have not received any reply!! But, this is a fundamental point in the IPCC theory, and it really needs a satisfactory explanation. NOT just an assumption or an assertion. It is concerning that the JULES model referred to above even tried using a value of ZERO for the specific heat capacity of a real surface which must contain mass. $\endgroup$ Commented Mar 12, 2022 at 9:37

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