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Temporal change detection

Definition

The comparison of multi-date images of the same area to identify pixels or features that have changed between acquisition dates. A disturbed grave site typically shows the strongest spectral anomaly in a scene acquired shortly after disturbance and compared to a pre-event baseline.

Related terms

Ground sampling distance (GSD)
The dimension on the ground represented by one pixel in an image. A 10 m GSD means each pixel covers a 10...
NDVI
Normalised Difference Vegetation Index. Computed as (NIR-Red)/(NIR+Red) from multispectral imagery. Values near 1 indicate dense healthy vegetation; values near 0 indicate bare...
NDWI
Normalised Difference Water Index. Computed from green and near-infrared or shortwave-infrared bands. Sensitive to water content in vegetation canopy and surface soil....
Synthetic Aperture Radar (SAR)
An active microwave sensor that generates its own energy pulse and measures the return from the surface. Cloud-penetrating and day/night capable. Backscatter...
Thermal infrared (TIR)
Sensor bands measuring emitted heat radiation (approximately 8-14 micrometres). Decomposing organic matter generates heat; soil with high moisture retains heat longer than...

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