They should have set a standardized way to measure heat content a long time ago. Don't know how anyone could ever claim that this science was settled. It has not even been done, from what I can see.
It’s worse than that. If you take a bunch of temperature readings and average them what does that really tell you?
Answer: Nothing
It just gives you the average of the readings from thermometers.
You have to be measuring the temperature of something for it to have meaning. In this case...air...which has mass. So where is the rest of the data. Where is the humidity and barometric pressure data to go along with the temperature data?
Air mass has to be normalized if you want to calculate a global “average” temperature of some air mass.