Scale effects and scaling-up by geometric-optical model

This is a follow-up paper to our “Scale effect of Planck’s law over nonisothermal blackbody surface”. More examples are used to describe the scale effect in detail, and the scaling-up of Planck law over blackbody surface is further extended to three-dimension nonisothermal surface. This scaling-up results in a conceptual model for the directionality and spectral signature of thermal radiation at the scale of remote sensing pixels. This new model is also an improvement of Li-Strahler-Friedl conceptual model in a sense that the new model needs only statistic parameters at the pixel scale, without request of sub-pixel scale parameters as the LSF model does.