Height changes - water levels

Hello everyone,
I am trying to get height change in the water level (rivers, lakes) from sar images,
How you guys suggest processing chain and method?
Is it possible directly through the interferometry to get differences?
If there are some related existing topics already, please navigate me?


Radar interferometry relies on high coherence at the ground. Unfortunately, coherence above water is nearly zero, so this would not work.

Sentinel-3 has a radar altimeter: http://www.altimetry.info/missions/current-missions/sentinel-3/
But SNAP is not suitable for this: The software you can use instead is called BRAT: http://www.altimetry.info/toolbox/ But I am not experienced with it at all and altimetry is also quite complex. Have a look at this page, it provides excellent material to get into it.

Thank you very much,
I will check then and s3 mission,

  • What do you think is it possible to get that maybe from coastlines or (some idea)…
    Thanks one more time I appreciate your help,


Mapping water bodies with SAR data is comparably easy, beacuse they are mostly black. You could investigate the change of the coastline which should mostly correspond to the water surface level.

Dear all,

I am trying to estimate water level of inland water bodies using Sentinel 3 Altimeter L2 data. I am processing the file in latest version of BRAT GUI 4.2.0 x 64. To estimate the water level I am using following equation:

alt_20_ku - range_ice_20_ku - iono_cor_alt_20_ku - mod_dry_tropo_cor_zero_altitude_01 - rad_wet_tropo_cor_01_ku - solid_earth_tide_01 - pole_tide_01 - mean_sea_surf_sol1_20_ku

While executing this expression in BRAT 4.2.0, I am getting error in reading mod_dry_tropo_cor_zero_altitude_01, rad_wet_tropo_cor_01_ku, solid_earth_tide_01 and pole_tide_01 correction data.

If anybody could successfully processed Sentinel 3 Altimeter data in BRAT, I request you to kindly help me to rectify this problem.

Your help in this regard is highly solicited.

Kind regards,

Vaibhav Garg

1 Like

I would suggest that you ask the Helpdesk of BRAT.

Thank you marpet