It is not «conduction» but
exchange of radiation; if you keep your hands parallel at a distance of some cm the right hand does not (radiatively) «warm» the left hand or vice versa albeit at 33 °C skin temperature they
exchange some hundreds of W / m ² (
about 500 W / m ²) The solar radiation reaching the surface (for 71 % of the surface, the oceans) is lost by evaporation (or evapotranspiration of the vegetation), plus some convection (20 W / ²) and some radiation reaching the cosmos directly through the window 8µm to 12 µm (
about 20 W / m ² «global» average); only the
radiative heat flow surface to air (absorbed by the air) is negligible (plus or minus); the non
radiative (latent heat, sensible heat) are transferred for surface to air and compensate for a part of the heat lost to the cosmos by the upper layer of the water vapour displayed on figure 6 - C.
When discussing
radiative thermal energy
exchange between two objects, it may very well be more appropriate to talk
about the heat between objects and not mention the rate thermal energy leaves each object in the direction of the other object.