Terrain flattening beta naught in the Arctic

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!

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

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

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