Dan,
It would be nice if anybody could even measure the energy content of the Earth system at a given point in time. Given present technology though, this is completely impossible.
Anyone who claims to be able to do so is either a fool or a fraud.
Even the surface temperature of the Earth eludes us. Measuring the supposed air temperature at a point above the surface is an exercise in futility, if the idea is to use that temperature as a proxy for the Earth’s heat content. It is just as bizarre as using the surface temperature of a column of water 10 km deep as a similar proxy, and the majority of the Earth’s surface is overlain by water of varying depths.
Satellite remote sensing is better, but it only reads the emitted radiation from what overlays the surface. Forest canopy temperature may tell you nothing about the surface temperature of the solid crust, some distance below.
To compound the farcical nature of so called global average temperature measurements, the effects of sunlight, clouds, aerosols, precipitation, CO2, H2O, the erratically rotating Earth, atmospheric perturbations (including wind), mean that the instantaneous temperature of the crustal overlay surface vary from moment to moment.
No amount of averaging or estimating will enable the calculation of the Earth’s heat content, which is necessary to establish energy difference between two points in time.
What has this to do with advocacy? Everybody wants to get their own way. If you can convince taxpayers to spend billions of dollars in accordance with your wishes, then good luck to you. More fool them, if it turns out your advocacy was based on complete and utter nonsense.
Let everybody advocate themselves to exhaustion! When the money runs out, or society changes, reality may prevail for a while. History is littered with the disastrous results of strident advocacy, supposedly based on expertise, science or both.
I don’t expect the future to change much in this regard, but who knows? I live in hope.