In physics, absorption is the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make transition between two electronic energy levels. The photon is destroyed in the process. The absorbed energy may be re-emitted as radiant energy or transformed into heat energy. The absorption of light during wave propagation is often called attenuation. This is a discussion of a present category of science. ... In modern physics the photon is the elementary particle responsible for electromagnetic phenomena. ... For other uses, see Atom (disambiguation). ... In chemistry, valence electrons are the electrons contained in the valence shell of an atom, and which are likely to participate in a chemical reaction through bonding with other atoms or molecules. ... For other uses, see Electron (disambiguation). ... A quantum mechanical system can only be in certain states, so that only certain energy levels are possible. ... Radiant energy is the energy of electromagnetic waves. ... Wave propagation refers to the ways waves travel through a medium (waveguide). ... Attenuation is the decrease in intensity of electromagnetic radiation due to absorption or scattering of photons. ...

The absorbance of an object quantifies how much light is absorbed by it. This may be related to other properties of the object through the Beer-Lambert law. In spectroscopy, the absorbance A is defined as , where I is the intensity of light at a specified wavelength λ that has passed through a sample (transmitted light intensity) and is the intensity of the light before it enters the sample (or incident light intensity). ... In optics, the Beer-Lambert law, also known as Beers law or the Lambert-Beer law or the Beer-Lambert-Bouguer law is an empirical relationship that relates the absorption of light to the properties of the material through which the light is traveling. ...

For most substances, the amount of absorption varies with the wavelength of the light, leading to the appearance of colour in pigments that absorb some wavelengths but not others. For example, an object that absorbs blue, green and yellow light will appear red when viewed under white light. More precise measurements at many wavelengths allow the identification of a substance via absorption spectroscopy. The wavelength is the distance between repeating units of a wave pattern. ... Color is an important part of the visual arts. ... Natural Ultramarine pigment in powdered form. ... For other uses, see Blue (disambiguation). ... For other uses, see Green (disambiguation). ... A yellow Tulip. ... For other uses, see Red (disambiguation). ... Absorption spectroscopy refers to a wide range of techniques where one measures how much light of a particular wavelength (color) is absorbed by a sample. ...

Earth surface

The specific phenomena involving absorption of electromagnetic radiation at the Earth's surface have several important aspects. These phenomena include regulating the temperature of the Earth's crust, surface waters and lower atmosphere. Changes in the Earth's crust such as glaciation, deforestation, polar ice melting, will necessarily alter the quantity and wavelength selectivity of electromagnetic absorption at the Earth's surface; correspondingly, changes in climate such as global warming may accompany changes in electromagnetic absorption or its inverse, the albedo.^[1][2] Regulation of the temperature of surface waters has been analyzed with respect to the influence of electromagnetic radiation absorption, indicating the effects of total solar insolation and the local albedo.^[3][4] For other uses, see Atmosphere (disambiguation). ... This article is about the geological formation. ... This article is about the process of deforestation in the environment. ... Global mean surface temperatures 1850 to 2006 Mean surface temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980 Global warming is the observed increase in the average temperature of the Earths atmosphere and oceans in recent decades and the projected... Albedo is the ratio of reflected to incident electromagnetic radiation. ...

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