Extension of the area surveyed with the multibeam system in the Ria de Aveiro, Portugal, onboard the NEREIDE research vessel.

A Kongsberg EM 2040 C multibeam echo sounder transducer installed on the scientific vessel NEREIDE, was used to collect multibeam bathymetry data during graduation activities. This particular dataset was collected around the Ria de Aveiro, Portugal during January, 2021.

The range of opening angles of the EM 2040 C multibeam varies between 60 and 65 degrees. The positioning system used was supported by the Real Time Kinematic (RTK) technique with the transmission of differential data in Ultra High Frequency (UHF) mode.

The data is calibrated and corrected for the surface sound velocity. The processing of hydrographic data was performed using specific algorithms for hydrography - Combined Uncertainty and Bathymetric Estimator (CUBE). In its processing, data was referenced to the hydrographic Zero of Portugal and projected in the ETRS89-PTTM08 coordinate system.