Atmospheric physics radiation (emitted by the sun) and terrestrial radiation (emitted by Earth's surface and atmosphere). Solar radiation contains variety of wavelengths. Visible light has wavelengths between 0.4 and 0.7 micrometers. Shorter wavelengths are known as the ultraviolet (UV) part of the spectrum, while longer wavelengths are grouped into the infrared portion of the spectrum. Ozone is most effective in absorbing radiation around 0.25 micrometers, where UV-c rays lie in the spectrum. This increases the temperature of the nearby stratosphere. Snow reflects 88% of UV rays, while sand reflects 12%, and water reflects only 4% of incoming UV radiation. The more glancing
Ultraviolet photography and it allows only the radiation to pass which is needed to induce a particular fluorescence. As before, a barrier filter must also be placed in front of the camera lens to exclude undesired wavelengths. Ultraviolet photography was used as evidence in court at least as early as 1934. Photographs made with ultraviolet radiation can reveal bruises or scars not visible on the surface of the skin, in some cases long after visible healing has completed. These can serve as evidence of assault. Ultraviolet imaging can be used to detect alteration of documents. Ultraviolet photography Ultraviolet photography is a photographic