Ref - surfacetemperatures - there are problems with calibration, arbitrary selection of stations, and the limited spatial sampling . The warmists will respond with " but there are satellite measurements as well".
temperature is only a proxy for heat if you are measuring a known, stable quantity
True, but it's not obvious to me why this is a killer fact ?
Ultimately, it's temperature that matters - I need to know if tomorrow I'm going to be subjected to zero degrees or 40 degrees, not how much "heat energy" there is in the oceans. Yes, the increased heat energy would heat the oceans at different levels. But again, what matters to life there is the temperature.
In any decent model, energy will be conserved. Globally, radiative energy comes in, there's energy going in and out due to chemistry, biology, phase changes, bulk movement, etc. Plus "heating", with associated temperature increase. Radiative energy goes out.
If the temperature measurements are poor, then the calculation of the heat energy is poor, and calculation of the radiative output is poor, modeling of convective flow may be poor. Beyond that ? Er, OK, predictions of biosphere behaviour will be be wrong - it'll all be out by the uncertainties in the temperature. But is this due to the heat capacity relation of temperature to heat energy ?