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Suppression of the Zero -- Temperature

I repeatedly make the mistake of discussion Climate Change analysis with people who don't want to talk about fundamentals.

I thought I would ask again then for why I shouldn't start my Temperature Charts at zero..

I know that starting there doesn't leave much of a chart for the Hockey stick people. The seem to have reasons for why we don't start there. Apparently I am nuts for suggesting it.

I grant that it is not absolutely necessary. I cannot accept that it is irrational. Fundamentally, what is temperature? Am I wrong to suggest that temperature is the average kinetic energy of whatever bounded system you choose? Doesn't that imply that a reasonable choice for zero would be the point where the kinetic energy is 0?

I am amazed at how hard it is to get anyone to talk about the idea of temperature. Apparently, temperature is something everyone understands so is beneath discussion. (Not necessarily here mind you, but in other places I attempt to talk about this devilish subject).

Re: Suppression of the Zero -- Temperature

We've discussed the idea of plotting the variation of global average temperature on some sort of 'absolute temperature' scale to avoid the 'chartmanship' associated with temperature anomaly plotting a few times in this forum, but I think starting from 0 deg K (or -273 deg C) is a bit over the top. That's taking the chartmanship too much in the opposite direction. On a temperature scale that starts with 0 deg K, even temperature swings between interglacial periods and full-blown Ice ages would look trivial. I've previously advocated starting the temperature axis at 0 deg C which I think is a reasonable starting point as the Earth would be just about still habitable at a global average temperature of 0 deg C.

However there is definitely one context where it would be most appropriate to look at the Earth's temperature variation on the Kelvin scale, when you're comparing temperature variations on Earth with other planets or moon of planets in the solar system. There was a news story about ten years ago where Triton (one of Neptune's moons) experienced a change in temperature from -392 deg F to -389 deg F over a period of ten years and this was quoted as being equivalent to a 22 deg F rise on Earth.

Re: Suppression of the Zero -- Temperature

At they discuss the average temperature of our planet A. without an atmosphere, B. with an atmosphere without GHG and C with an atmosphere with GHG. One of the curiosities of averages here is the loss of important information. It turns out apparently that our planet with an atmosphere would be a little warmer than with (but without GHG) because of albedo. What gets lost in the compilation of the the data down to a single number is the breadth of temperatures that would be seen on a planet with no atmosphere.

A different point to start charts from I discovered the other day when refreshing my abilities to read a Mollier diagram. The point we describe as Zero Enthalpy, which I believe (if I read correctly) corresponds with the Triple Point of water.

In any case, the zero point should be something I can replicate without need to resorting to Harry Read Me type analysis. I can go into the lab and find the freezing point of water. I can find the Triple point of water. I can find the point at which molecules stop moving. I can find the point at which water boils. I don't have to have an advanced degree in computer science, statistics, and climate science to establish what the zero point is (a la our current system of anomalies with hidden internal dependencies).

I would happily agree to any zero point that is tied to a physical constant.

This does not mean however that I think the Gold Standard is a good thing.