Sentinel-1: Difference in intensity values

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#1

I am processing some IW GRDH images from Sentinel 1 in an area where two parallel orbits overlap. However, there is an order of magnitude difference in intensity between all images from the two orbits.

Do you know why it can be?

Thanks

S1A_IW_GRDH_1SDV_20211102T181848_20211102T181913_040396_04C9CF_F2EC_Intensity_VV
S1A_IW_GRDH_1SDV_20211102T181848_20211102T181913_040396_04C9CF_F2EC_Intensity_VV1076×692 190 KB

S1A_IW_GRDH_1SDV_20211109T181039_20211109T181104_040498_04CD6A_B0EE_Intensity_VV
S1A_IW_GRDH_1SDV_20211109T181039_20211109T181104_040498_04CD6A_B0EE_Intensity_VV1076×692 195 KB

#2

The radar backscatter intensity will vary with the incidence angle. If these are from two different tracks that overlap, then the incidence angle will be different by up to 15 degrees, depending on the latitude. In addition, there can be changes in radar backscatter intensity over time due to rain or snow changing the surface properties.

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