Albedo planet would drop to about 0 °C. In contrast, if the entire Earth was covered by water — a so-called aquaplanet — the average temperature on the planet would rise to almost 27 °C. For land surfaces, it has been shown that the albedo at a particular solar zenith angle "θ" can be approximated by the proportionate sum of two terms: the directional-hemispherical reflectance at that solar zenith angle, formula_1, and the bi-hemispherical reflectance, formula_2, with formula_3 being the proportion of direct radiation from a given solar angle, and formula_4 being the proportion of diffuse illumination. Hence, the actual albedo
Albedo (alchemy) Albedo (alchemy) In alchemy, albedo is one of the four major stages of the magnum opus; along with nigredo, citrinitas and rubedo. It is a Latinicized term meaning "whiteness". Following the chaos or "massa confusa" of the nigredo stage, the alchemist undertakes a purification in albedo, which is literally referred to as "ablutio" – the washing away of impurities. In this process, the subject is divided into two opposing principles to be later coagulated to form a unity of opposites or "coincidentia oppositorum" during rubedo. Titus Burckhardt interprets the albedo as the end of the lesser work, corresponding to a