“Just as a burning candle placed in the corner of a room will heat the room to some extent”
Here is an experiment. Take a slab of water, insulated on all sides by a perfect vacuum, and start heating it by strong sunlight. Watch how slowly that water will cool down once the solar is removed.
That’s right, it only cools relatively slowly because I have just artificially created a thermos bottle. In a vacuum, the slab can only dissipate thermal energy by infrared radiation, and this is a sllow process for lukewarm temperatures.
The fact is that water can warm and cool by a number of mechanisms, and if one wants to be complete about it, then you have to consider all the pathways for dissipation, whether it be radiation, convection, evaporatiom/condensation, melting/freezing, dilution, or thermal conduction/diffusion.
What Hansen did was remove all the exchange mechanisms that are conserving (such as phase changes) and treated the general convection problem as a random walk (i.e. convection can go either way). This then creates a modeling scenario that involves a radiation forcing term, an interface between two volumes, and a diffusional mechanism. The result is the general Fickian response (i.e. uptake is square root with time) that shows up in the thermal response curves from Hansen’s papers published in the early 1980′s.
Does everyone now understand what this is all about? Probably not, because faux skeptics don’t want to understand.
BTW, this turns the scenario into a planar diffusion problem, one of those problems that for me, as a semiconductor physicist, I can solve in my sleep. Diffusion is diffusion and the master equations are similar in construction.