A simple CO2 model
10/18/2019 09:23 - Posted by Tom van Leeuwen
In this video Professor of Astronomy Michael Merrifield (University of Nottingham) presents a simple model of the CO2
He leaves out clouds, albedo effect, ocean interaction, sun cycles and a lot of other factors that affect the climate and discusses only the CO2
radiation in the atmosphere.
His main argument is that when the CO2
-concentration rises, the atmosphere will start emitting from a higher layer. The temperature at that emitting layer has to be -18 °C. So, if the -18 °C temperature layer is higher up in the atmosphere and as the temperature rises 6.5 °C for each kilometer we go down from that layer, the surface temperature will go up.
At first glance, an important problem arises. The -18 °C emission temperature is calculated subtracting the total greenhouse effect (33 °C) from the average surface temperature (15 °C). But, of course, while the average surface temperature is 15 °C, the real measured temperatures of the Earth's surface vary at any moment between -40 °C and +35 °C, while in the higher atmosphere such a temperature variation between latitudes does not exist. So the first question is whether this model would work at all in the real world.
But, that's the model. Now, let's fire up some modeled diesel-engines, build some modeled coal plants, emit some additional CO2
and take this model to the limit
As we add more CO2
the emitting point will go up, so if we add a lot more, at some point the emitting level will reach the tropopause
. In the tropopause, the temperature won't decrease any more with higher altitudes, so from that point on, adding more CO2 will not have any effect
on the Earth's temperature according to this model.
If we still add a lot more CO2
, the emitting point will reach the stratosphere
. In the stratosphere, the temperature will go up with higher altitudes so, according to this model, the surface temperature must go down
If you take this model to the limit, it tells you that temperatures will drop when you add more CO2
Doesn't sound very convincing, right? The CO2
-concentration goes up and the temperature goes down. But that is what the model tells us.
Clearly this model fails. It's an oversimplification of the real world.
In the real world, the CO2
greenhouse effect has a logarithmic progression and is mostly saturated. Adding more CO2
has no measurable effect on the surface temperature. This is reflected in real-world empirical data
Tom van Leeuwen, October 18th, 2019.