spectral signature

In remote sensing, a spectral signature refers to the specific set of wavelengths or frequencies of electromagnetic radiation that are emitted or reflected by an object or surface. These signatures can be used to identify and analyze the composition of materials on the Earth's surface.

For example, vegetation has a characteristic spectral signature in the visible, near-infrared, and shortwave infrared regions of the electromagnetic spectrum. This signature can be used to detect and map vegetation cover, classify different types of vegetation, and monitor changes in vegetation over time. Similarly, minerals have unique spectral signatures in the visible and infrared regions of the spectrum, which can be used to identify and map mineral deposits and to monitor changes in mineral cover.

Remote sensing instruments, such as satellites and aircraft, collect data across a range of wavelengths, and by analyzing the spectral signature of the reflected or emitted radiation, scientists can identify the types of materials present on the Earth's surface. This information can be used for a wide range of applications such as land use and land cover mapping, natural resource management, and environmental monitoring.

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Supervised Classification

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