Terrain flattening beta naught in the Arctic

Microwave Toolbox
#1

Hi everyone,

I’m working with an S1B_EW_GRDM_1SDH product that is located in the Arctic. My goal is to radiometrically terrain flatten beta naught to receive a terrain corrected gamma naught. However, understanding that most DEMs are not fitted for the Arctic, I’ve tried everything from Tandem-X 90m, GETASSE30, ACE2, CDEM, and yet the resulting gamma naught image is just a black square.

My steps are as follows:

  • Apply Orbit File
  • Radiometric -> Calibrate -> Output beta0 band
  • Single Product Speckle Filter
  • Radiometric -> Radiometric Terrain Flattening -> highlighted my Beta0 HH and HW -> changed the DEM -> resampled using Bilenear_Interpolation

I’m specifically looking for the terrain corrected gamma naught as my final variable.

Any help would be much appreciated! Thank you!

#2

Have you tried the Copernicus DEMs that are global and also cover the Arctic?

#3

Hi @mengdahl, I’ve tried both of the Copernicus DEMs and I still get the black image.

#4

You should check whether SNAP downloaded the DEM tiles and whether they look ok.