ATOC 181 Lecture Notes - Lecture 5: Stratocumulus Cloud, Permafrost, Shortwave Radiation
12 Oct 2017
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Radiation does not require medium (can use vacuum) Scattering: deflection of light in all directions by small particles/droplets and/or irregularities in fluid medium. Reflection: light send backward by an interface between 2 different media; can be specular (mirror effect) or diffuse (reflection in many directions) Em waves may be reflected to space as they bounce off the earth"s surface. Depends on surface cover and angle of sun. Snow reflects up to 95 % of radiation. Large liquid water bodies (oceans, deep lakes) absorb up to 98 % of radiation (depends also on angle of incoming light rays). Albedo: fraction of incident shortwave radiation that is scattered (reflected) back to space. Albedo represents reflectivity of a surface to shortwave radiation. Blackbody: an object that absorbs all incoming radiation and emits the maximum possible radiation at its temperature. Both sun and earth"s surface behave like blackbodies (in their range of em wave emission) but the atmosphere does not.
