OPERA Radiometric Terrain Corrected SAR Backscatter from Sentinel-1 (Version 1) 2024-11

The Observational Products for End-Users from Remote Sensing Analysis (OPERA) Radiometric Terrain Corrected (RTC) SAR Backscatter from Sentinel-1 (S1) validated product consists of radar backscatter normalized with respect to the topography. The product maps signals related to the physical properties of ground scattering objects, such as surface roughness and soil moisture and/or vegetation. The OPERA RTC-S1 product is derived from Copernicus Sentinel-1 Interferometric Wide (IW) Single Look Complex (SLC) data with a near-global scope and temporal sampling coincident with the availability of S1 SLC data. Each OPERA RTC-S1 product corresponds to a single S1 burst projected onto a pre-defined UTM/Polar stereographic map grid with 30-metre spacing. The Copernicus global 30 m (GLO-30) Digital Elevation Model (DEM) is the reference DEM used for topographic correction and geocoding. The product is normalized to the gamma-naught (γ0) backscatter coefficient and distributed as Cloud Optimized GeoTIFFs (one per polarization), with metadata in HDF5 and ISO†19115-2 XML formats. Static radar-geometry layers (incidence angle, local incidence angle, number of looks, RTC Area Normalization Factor) are provided separately as the OPERA RTC-S1-STATIC product. The OPERA RTC-S1 product contains modified Copernicus Sentinel data (2014–present). The OPERA project is funded by NASA’s Satellite Needs Working Group (SNWG).