SLC or GRD for Water-logging in urban areas

Microwave Toolbox
#1

I am working on water-logging in urban areas. For my study, will SLC data be more useful than GRD data?

Flooded Vegetation
Two-time RGB composite image interpretation
#2

Hi,
in Most of the studies, backscatter analysis is used on identifying water-logged areas, hence, GRD data. Water-logged areas produce higher backscatter (due to water content) compared to dry areas.

There are few studies conducted using Interferoemtry to detect soil moisture (which is similar to what you try to do)

Here is an article that summarizes some of the techniques used: soil moisture retrieval_current techniques.pdf (425.2 KB)

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Satellite soil moisture estimation using sentinel 1 and sentinel 2 data in snap toolbox
#3

Hi,
My concern about grd is the spatial resolution. For urban water logged regions, the spatial resolution will be crucial compared to soil moisture analysis in a rural landscape. Is it possible to achieve higher spatial resolution by using SLC data ?

#4

The SENTINEL-1 IW GRD data have spatial resolution of 20 x 20m. If you look at water-logged areas in rural environment where big fields get flooded, the spatial resolution of SENTINEL-1 GRD data is enough to identify those areas.
If you try to identify flooded areas within a dense urban environment, this is much harder.

On the other hand, using interferometric technique, we do not look at the amplitude of the image (as in GRD) but the phase. This is a completely different methodology compared to using GRD data for identifying water-logged areas. Interferometry does not work well in vegetated areas. If interferometry is applied for identifying water-logged areas, you need to make sure that your AOI is a bare ground (no trees or heavy vegetation).

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