Le Chatelier and Global Warming 

          Watching the billions of dollars go by in the discussion of “global warming,” now “climate change,” leaves the independent physical scientist wondering if he has not lost his mind or landed in Hell. 

          One of the great principles of physical science is the Le Chatelier Principle which is: 

“If a chemical or physical system at equilibrium experiences a change in concentration, temperature, volume, or total pressure; the equilibrium will shift in order to counter-act the imposed change.” (Wikipedia) 

          The axiom should include that, “The shift will be accomplished in the way least disturbing the elements involved,” because we observe that to be the case where the system strictly obeys the Second Law of Thermodynamics and takes “the easy way out.” 

          Suppose we take a liter of air in a sealed container.  It will contain 780 ml of N2, 186 ml of O2, 30 ml of H2O vapor and 0.38 ml of CO2. 

          Where a “molar” weight is the mass in Atomic Weight Units in grams we have:  0.0348 mole N2, 0.00831 mole O2, 0.00134 mole H2O and 0.0000169 mole CO2.  So the Le Chatelier expression of this equilibrium is: 

[N2] X [O2] X [H2O] X [CO2] = K 

And, in our numerical case… 

[0.0348] X [0.00831] X [0.00134] X [0.0000169] = 6.55 X 10^-12 

          The question of the day is, “What will happen when we increase the CO2?” 

          Under a “common sense” protocol increasing CO2 should do nothing because there is no lid on the atmosphere.  The pressure should not be an issue, but clouds form and this suggests the atmosphere functions as a closed system; one with a cork in the bottle.  The “cork” is statistical, but effective.  Assuming it is closed, CO2 should raise the pressure, but that would be a stress in a closed system.  What happens? 

          Increasing pressure requires energy, but there is one system within the set that produces energy in response to pressure.  Water vapor precipitates and in so doing produces 550 kilocalories per mole.  If you have been outside just before a rainstorm you have felt the spike in the temperature.  This is from where it has come.  The stress triggering it was possibly nothing more than thunderclaps as they have kinetic energy, hence validating the myth battlefield cannon set off rainstorms.  Bombs did this in Germany during WWII. 

          And so what we would expect to see as CO2 levels increase is a reduction in the amount of water vapor with a consequent reduction in atmospheric heating as it absorbs eight times as much per molecule.  But, why are we even talking about CO2 atmospheric heating when the total of its’ effect is 1/1600^th that of water vapor?

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