The Enhanced Greenhouse Gas Theory for Global Warming contravenes
the Law of Conservation of Energy
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The Enhanced Greenhouse Gas theory for global warming is invalid because it contravenes the Law of Conservation of Energy. This law states that energy can neither be created nor destroyed, but can be changed from one form to another. This applies to energy in all of its forms. This is supported by the First Law of Thermodynamics, although this is principally concerned with sensible heat energy.
This claim will, no doubt, be found unacceptable by many because of the established Natural Greenhouse Gas Theory, which explains Earth’s temperature of about 14 degC. But there is a subtle, but important, difference between the two theories, which will be dealt with.
Both theories have the basic requirement of energy balance, which means that the output energy flowing to space must be equal to the input energy from the Sun.
The Natural Greenhouse Gas Theory
In the early periods of the development of the Earth there was no fixed temperature or atmospheric concentration of carbon dioxide, and so no possibility of the energy balance condition being achieved. Over time, however, things settled down to the stable state before anthropogenic activities commenced, and so energy balance was eventually attained with a temperature of 287.6 K and a carbon dioxide concentration of about 280ppm.
Had the carbon dioxide concentration been higher, then the amount of energy absorption, and hence the temperature, would also have been higher in order to maintain energy balance. Also, the inverse.
It is generally understood that without any greenhouse gases in the atmosphere the surface temperature of the Earth would be about 255 K, that is about – 18 degC, or 33 degC cooler than the real temperature of 287.6 K, or 14.5 degC.
A state of stable equilibrium was established at 287.6 K, meeting the fundamental requirement of energy balance.
The input power received from the Sun is given by (S/4)(1 – a)
where S = Solar Constant 1362 Watts per square metre
a = albedo 0.3
(It must be noted that this uses NASA’s method of using “average” values by dividing the solar input by 2 for latitudes and again by 2 for the diurnal effect.). This provides a value for the input power of 238.35 Wm^-2.
Therefore, by the balance condition requirement, the output power to space must also be 238.35 Wm^-2, with a surface temperature of 287.6 K.
The Stefan-Boltzmann Law enables the output power from the surface to be calculated for this temperature. P = esT^4 where e is the surface emissivity, taken as an approximation here to be 1.0
and s is the Stefan-Boltzmann constant 5.6704 x T^4
So, at T=287.6 K, the output power radiated by the surface is 387.94 Wm^-2.
Some of the infrared energy radiated to space by the Earth’s surface can be absorbed by the atmospheric greenhouse gases such as carbon dioxide, methane, and water vapour. This is then re-radiated, with half rejoining the flow to space, and half flowing back to the surface. This will be referred to as the “Earth Return”. This is in line with the Greenhouse Gas theories, both Natural and Enhanced.
So then we have the pre-anthropogenic situation as follows (power in Wm^-2), illustrating energy balance.
From Sun Surface Space
238.35 387.94 238.35
This is satisfying the energy balance condition.
The Enhanced Greenhouse Gas Theory
1. Before anthropogenic activities, the Earth had achieved the required condition of energy balance, with the output energy from Earth to space equal to the input energy from the Sun. This satisfies the Natural Greenhouse Gas Theory, and is the starting condition for the Enhanced theory.
The Earth is in a condition of energy balance.
2. Anthropogenic activities caused more carbon dioxide to be emitted into the atmosphere, and so more energy was absorbed. Let this extra amount be A. This is then re-radiated, and the amount going to rejoin the output to space is 0.5A, and the Earth Return is also 0.5A.
This means that there is a shortfall of 0.5A in the output to space required by the balance condition, and so this must be restored. So far, the Enhanced GHG theory is in line with this.
3. But the Enhanced GHG theory claims that extra energy is radiated from the surface in order to make up the shortfall, and so restore balance. Fundamental mistake.
If this were so, there would then be more energy than before the extra CO2 emission, because the energy to space would have been restored to its initial value as in stage 1, and there is also now the Earth Return, 0.5A, which must be taken into account.
So the Law of Conservation of Energy is contravened, because energy can neither be created nor destroyed.
The Enhanced GHG theory compounds the mistake by claiming that the extra energy to make up the shortfall arises from an increase in surface temperature, so more energy is radiated, in line with the fourth power temperature dependence of the Stefan-Boltzmann Law and Planck’s Law.
But this explanation is too simple, incomplete and incorrect. What would make the surface temperature higher. More energy, of course, and hence more output radiation as required. But if energy is removed from the surface, it will cool down, and so the extra emission needed to respond to the shortfall fails. Therefore, still more energy must be supplied to the surface in order to maintain the required higher temperature and the required greater radiation. But energy cannot be created, so the Enhanced GHG theory fails too; it is still violating Conservation.
The amount of energy which can be radiated by a body is proportional to the fourth power of the temperature, but energy cannot be created and so a suitable supply of energy must be available.
Therefore, the Enhanced Greenhouse Gas theory for global warming is not valid.
It was a fanciful idea based simply upon a correlation between anthropogenic activities and the very real measured increase in global temperatures now causing serious climate change.
This is very likely due to anthropogenic activities, but not carbon dioxide.
So what does happen when more greenhouse gases are emitted into the atmosphere?
However, absorption by the greenhouse gases does, in fact, occur as in stage 2, so causing a “shortfall”, and this must be made good in order to maintain the power balance condition. So, energy is required, but it cannot be created, so where does this notional amount come from?
In fact, there is a suitable supply already mentioned in passing above. It is the Earth Return, and this has been completely ignored by the Enhanced GHG theory. It is 0.5A, just the required amount to cope with the shortfall, and it has entered the surface. It cannot remain in the surface, because this would aggravate the problem, as above. But it can be re-radiated to space without any need for increased temperature. It cycles from initial absorption, through re-radiation to the surface where it is absorbed, and then re-radiation to space. This maintains the balance condition. And this process is continually repeated.
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