Land Surface, Temperature
Land surface temperature (LST): Average temperature of an element of the exact surface of the Earth calculated from measured radiance (for a complete definition, see Norman and Becker 1995).
Blackbody: An ideal material absorbing all incident energy or emitting all thermal energy possible. A cavity with a pinhole aperture approximates a blackbody.
Color temperature: Temperature satisfying Planck’s law for spectral radiances measured at two different wavelengths: for a graybody (this entry); for any emitter; blackbody temperature for which visual color is the same as some other source (e.g., in photography).
Emissivity ε: The efficiency with which a surface radiates its thermal energy.
Irradiance: The power incident on a unit area, integrated over all directions (W m−2).
Longwave infrared (LWIR): For most terrestrial surfaces (~340–~240 K) peak thermal emittance occurs at LWIR (~8–14 μm).
Mid infrared (MIR): Forest fires (~1,000–600 K) have