If the average temperature of Earth increases when carbon dioxide in the air increases, then the warming effect should be greatest at the poles (where the additional CO2 does not have to compete with the main greenhouse gas -- 2% to 4% water vapor in the air -- as it would have to do in the tropics).
The very cold air at the poles can hold only very small amounts of water vapor.
So the effect of more CO2 should be largest in the polar regions, because they have very low humidity.
But … the southern polar region has been cooling for the entire 37 years since weather satellites began measurements.
The cooling trend is slight (not statistically significant vs. a flat trend) … but this is the real news -- there would be statistically significant WARMING there if CO2 really was the "climate controller", as 'global warmists' claim.
The actual cooling trend at the southern polar region could be much longer than 37 years if we had accurate records before 1979.
"Climate" is sometimes defined as conditions over a 30 year or longer period.
That means (at least) 37 years with no warming in the southern polar region is significant, and is evidence that CO2 is not a "climate controller".