Originally Posted by David M
What this seems to show is that a constant temperature for the planet is not normal.
That depends on the time scale you're considering, and what you mean by 'constant' and 'normal'.
Huge temperature variations occur geologically (millions+ years) because of changing continent configuration. Within that (thousands+ years), small oscillations occur due to orbit and solar
cycles (glacial/inter-glacial). On the span of a few human lifetimes (hundreds+ years), you wouldn't expect much change at all, unless you add another forcer (in the present case, burned fossil fuel).
Otherwise, find another (non-anthropogenic) forcer of sufficient magnitude, while explaining why the known laws of physics don't seem to apply to the anthropogenic greenhouse gasses, which just so happen to occur in the right concentrations to cause exactly the magnitude of warming observed. Then collect your Nobel Prize for physics.