Spatialization and analysis of the GNSS-R measurements around of the Cordouan lighthouse

Research around the Cordouan Lighthouse in the Bay of Biscay reveals significant tidal variations in sea level measurements using GNSS reflectometry (GNSS-R). However, submerged sandy banks at low tide disrupt these measurements. The study spatialized GNSS reflection points to distinguish between sandy and rocky areas, creating a map of water height estimates based on reflection point positions. By analyzing 1-second Signal-to-Noise-Ratio (SNR) data over sliding elevation windows and correcting atmospheric delay effects, the team reduced dispersion in water heights by a factor of two. The findings show high variability (over one meter) and elevated mean water heights in the eastern part, consistent with known shoals, while oceanic areas exhibit much smaller variations. This distinction is further emphasized by differences between low and high tides.

Gravalon, T., Seoane, L., Ramillien, G., & Darrozes, J. (2023). Spatialization and analysis of the GNSS-R measurements around of the Cordouan lighthouse. https://doi.org/10.5194/egusphere-egu23-7957