Deformation mapping of deltas using S1A IW SLC imagery

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1

Hi all,

I’ve created a deformation map of the Ayeyarwady delta and I am unsure as to the validity of my results. First, the data is over a four year time span. I chose imagery from January 2016 to January 2020 as this is the dry period of the Ayeyarwady delta and I understand that though coherence is lower in agricultural areas than urban areas, it can still prove valid if mapped during the dry season. The recipe I followed is similar to the deformation mapping recipe provided by STEP, just with a few adjustments.

methodology|690x435

After mosaicing the delta together I used the K-means cluster reclassification to smooth out the data set.

annual_disp_kernelupdated.tif (671.6 KB)

Here is the annual displacement prior to using the K-means reclassification

ad1.tif (1.9 MB)

How can I be sure that the deformation seen in the imagery is uplift/subsidence and I have not mistakenly mapped deforestation or a hydrological process?

AP

2

4 years is a extremely long time for an interferogram and I would expect that between two images nearly every pixel is decorrelated during this time and the phase information no longer usable.
The pattern you see in this image is interesting but could be caused by atmospheric disturbances as well. You can try a different image pair of similar acquisition dates (e.g. +12 days each) and see if the pattern is the same or not.