The ERS SIR-Enhanced product (NSIDC-0808) provides normalized radar cross section (σ⁰, Sigma0) or radar backscatter data derived from the European Space Agency (ESA) Earth Remote Sensing satellite series (ERS-1 and ERS-2) Active Microwave Instrument (AMI) in scatterometer-mode (ESCAT) during satellite overpasses between January 1992 and January 2001. The ESCAT instrument is a C-band (5.3 GHz) radar that collects σ⁰ at a vertical transmit–vertical receive (VV) polarization. NSIDC-0808 includes both conventionally gridded (GRD) and enhanced-resolution (SIR) backscatter images gridded to EASE-Grid 2.0 azimuthal and cylindrical projections (Brodzik et al., 2012; Brodzik et al., 2014) at two grid spacings (25 km and 6.25 km). The data set provides near-global coverage and supports studies of land, ice, and cryospheric surface processes sensitive to σ⁰ , including surface freeze/thaw state, snow and ice structure, and moisture variability.