काशानुपात ( Albedo )

Submitted by admin on Wed, 03/04/2009 - 13:02
परावर्तित एवं आगामी विकिरण का अनुपात, जिसे प्राय: प्रतिशत में दर्शाया जाता है।

Ratio of reflected to incoming radiation, usually given in percent.

Albedo


From Wikipedia, the free encyclopedia

The albedo of an object is the extent to which it diffusely reflects light from the Sun. It is therefore a more specific form of the term reflectivity. Albedo is defined as the ratio of diffusely reflected to incident electromagnetic radiation. It is a unitless measure indicative of a surface's or body's diffuse reflectivity. The word is derived from Latin albedo "whiteness", in turn from albus "white". The range of possible values is from 0 (dark) to 1 (bright).

Percentage of diffusely reflected sun light in relation to various surface conditions of the Earth The albedo is an important concept in climatology and astronomy. In climatology it is sometimes expressed as a percentage. Its value depends on the frequency of radiation considered: unqualified, it usually refers to some appropriate average across the spectrum of visible light. In general, the albedo depends on the direction and directional distribution of incoming radiation. Exceptions are Lambertian surfaces, which scatter radiation in all directions in a cosine function, so their albedo does not depend on the incoming distribution. In realistic cases, a bidirectional reflectance distribution function (BRDF) is required to characterize the scattering properties of a surface accurately, although albedos are a very useful first approximation.

Courtesy - Wikipedia

Tags - Albedo in Hindi.