Chris, you write “You test that physical theory against the data. That’s how science works.”
Yes and no. We have not got that far yet. All we have, and all Girma shows, is ALL the data plotted on one graph. If there was more data, it would be plotted. What the data shows is that temperatures have been rising linearly since the data started. On top of this linear trend is some sort of sine wave. So far as I am aware no-one has any idea why this is happening. So there is no theory to explain the data. All we know is that there are factors which affect temperature, and which have produced the observed results. What these factors are is unknown. Yes, people have ideas what they might be, but there is no coherent theory to explain the data.
However, what the data clearly shows is that there is no CO2 signature, as hypothesised by the proponenst fo CAGW. If there was a CO2 signal, then by now the observed temperatures would be outside the +/- 0.25 limits; on the high side. This has not happened; this is Trenbeth’s “missing heat”. this is what the CAGW hypothesis completely fails to explain.
Of course this trend has not been going on for millenia. Nor will it last for millinia into the future. There are clearly long term factors which affect temperature, and which for the moment are not having any effect.