MSimon. I've noted before on this thread that you are a better engineer than this. You understand control. You must understand that most systems have some dynamical deterministic aspect on which is superimposed random stuff - noise. Or at let they can successfully be analysed like that.
Climate is supposed to be the dynamical deterministic bit but of course there are man different random (or at least not easily predictable) forcings - and there is CHAOS which means that internal chnages in the system mean pretty well any parameter you want to measure is going to show random movement around its average value.
In climate, we know this random stuff has timescales of weeks, months, years, even decades. For the longer stuff (decades) we've got pretty good handles that tell us how much of it works (ENSO/AMO models etc).
Now, CO2 rising gives us around a 0.12C - 0.2C/decade trend. The
random noise on the average global temperature looks larger than this over decades. If you look at the temperature record you can see that 15 years is no where near long enough to get an accurate value for the trend because of this. You would expect segments with much lower or much higher apparent trend due to the noise. In fact over a short time period - say 15 years - you would rarely expect on-trend warming. You'd expect higher than trend some times balanced by lower than trend at others. I think you know this - it would be true of any control system with noise. So I can only imagine your comment below is because you are not thinking clearly due to major prejudice.
There is math that tells you whether a particular segment of a random process is significant for a given model. Have you tried using this? On correctly baselined anomalies?
If we had no idea what was causing the current pause the historic record of variability would be enough for us to see it as normal.
But we DO have an idea what things drive these decadal long fluctuations:
TSI (low)
ENSO/AMO (negative)
There is enough uncertainty about this stuff that you cannot rule out some other decadal forcing we DONT understand. But that will be a modification of what we'd reckon if it was not there - not something that can completely overturn all the other stuff.
If CO2 has no effect on temperature effect then something must be stabilising the climate so much that CO2 forcing (known and simple science - empirically validated through direct observations of IR spectra from earth atmosphere by satellites - gets flattened by negative feedback. But it is very very difficult to think of a powerful negative feedback mechanism that applies to CO2 forcing but not to other forcings - aerosol, TSI, etc. The fact that the earth's temperature is sensitive to those other forcings means it must also be sensitive to CO2.
Therefore your claims here are unsubstantiated and have strong contrary evidence. Creeks and paddles come to mind again.
MSimon wrote:We have had warming, just not as much as usual.
But CO2 is rising. Shouldn't there be more than usual?