Methodologies to evaluate changes in the surface of the earth

Hi to every one, my name is David and I am from COLOMBIA, and i am about to finish my studies on civil engeeniring.

At this moment i am doing my thesis and i want to evaluate the factibility to use remote sensing techniques for identify landslides or changes in the surface of the earth here in my country. Specificly, i want to implement monitoring process in many parts from my country to improve the risk management.
The problem is that i am new in this topics and i want to know if anyone have some methodology or step by step for this, because this is only a part from my thesis and is not the final objective from it.
I was finding this and i could not found articles about generate maps from changes of the earth.
I already know everything about downloading the images, but I don’t know how to process them in the SNAP program to identify the surface changes.
If anyone has an article that can serve as a reference for my work, I will be very grateful to share it.

I remind you that my research is for educational purposes only. I am in the last year of civil engineering at the EIA University in Medellin Colombia

1 Like


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)