In principle, different land cover such as forests and built-up areas can be identified from their spectral reflectance signature, provided the sensing system has sufficient spectral resolution to distinguish its spectrum. For more information, see, for example, http://www.sci-ctr.edu.sg/ssc/publication/remotesense/optical.htm
a characteristic set of reflectances over the electromagnetic spectrum
A characteristic shape to a spectrum which can be used as an unambiguous indicator of some chemical constituent (or vegetative component) of the area being studied.
An object's spectral signature is the distinctive set of wavelengths of electromagnetic radiation (light) it either absorbs or emits. Every element has a unique spectral signature that can be used to identify it, like a fingerprint.
The variation of reflectance with wavelength for an object.
The specific manner in which a particular surface reflects electromagnetic radiation. Usually given as the percentage reflected in each spectral band.
Quantitative measurement of the detected properties of an object at several wavelengths.
The reflectance of a particular object or surface material plotted against increasing spectral wavelength. The resulting patterns can be used to identify objects or materials if they differ from those of other objects or materials.
The quantitative measurement of the properties of an object at one or several wavelength intervals. Spectral signature analysis techniques use the variation in the spectral reflectance or emittance of objects as a method of identifying the objects (NASA).
Spectral signatures are the specific combination of reflected and absorbed electromagnetic radiation at varying wavelengths which can uniquely identify an object. The ""Spectral signature"" of an object is a function of 1) incidental EM wavelength and material interaction with that section of the (electromagnetic spectrum). The measurements can be made with various instruments, including a task specific spectrometer, although the most common method is separation of the Red, Green, Blue and Near Infrared portion of the EM spectrum as acquired by digital cameras.