John A, one of the bloggers at Climate Audit writes:
You should know that Lambert’s scientific knowledge is *ahem* “challenged”. Ask him if he’s discovered what entropy is and how it applies to closed thermodynamic systems.
What a guy.
Following the link, we find an anonymous person defending McKitrick’s false claim that average temperature has no physical meaning. I had explained that the physical meaning of the average temperature of two bodies was the equilibrium temperature you obtain when you let heat flow from the hotter body to the cooler one and that this was just the weighted average. Mr anonymous claims this is wrong because:
I’m sorry but I’m not going to quote you large parts of undergraduate texts on thermodynamics as it applies to closed systems where the energy is conserved. It has to do with the concept of Work and the quantity of disorder in a closed system called entropy. If you join two separate systems together then in order for the conductor to transmit energy it must do work. If it does work, the total amount of entropy must increase. In order for entropy to increase it must take thermal energy from the system. If it were not true then you could remove the conductor and the situation would be reversible. The result is that because entropy must increase, and total energy is conserved then the resultant temperature must be less than the “weighted average” of the two separate systems.
That’s why Lambert has run off like a little girl – because he’s realised he’s made a big mistake that could be spotted by any competent undergraduate of physics. The non-decreasing nature of entropy means that his simple argument falls to the ground.
It looks like John A thinks total energy = thermal energy + entropy, which is, umm, not exactly true. I think it is all explained here.
Update: Mr anonymous responds to my post asserting that he really does believe that total energy = thermal energy + entropy. The SI unit of entropy is Joules per Kelvin (as it says in the first paragraph of the Wikipedia entry on entropy that he cited). His equation makes as much sense as adding pounds to miles.