Methodologies to evaluate changes in the surface of the earth

Microwave Toolbox Interferometry
2

Hi,

In terms of detecting changes on the surface of the Earth (landslides, earthquakes, floods, subsidence, e.t.c) the mainly sensors that are used for this purpose is SAR (Sentinel-1). There are two different techniques to change detection:

  1. Coherenet change detection where we use the only phase of the radar signal to detect changes. The type of SAR data used in this case is Single Look Complex (SLC)
  2. incoherence change detection where we use the intensity of the radar signal to detect changes. The type of SAR data used in this case is Ground Range Detected (GRD)

Incoherent change detection is more straight forward and less complicated. Bear in mind that, due to the fact that the spatial resolution of GRD data is 20x20m, in order to detect any change due to landslide, the change should be bigger than the spatial resolution (>20m)

If you want to apply the methodology for landslide detection based on the intensity of SAR data you can follows the ESA Echoes in Space video. This tutorial is focused in detecting floods, but you can use the same processing steps in your purpose.

Also, you can have a look at the following papers

Coherent Change Detection with SAR.pdf (347.5 KB)

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