The Polar Surface Water (PSW) and the Atlantic Water (AW) characteristics and their vertical extent are investigated using data from three moorings deployed in the Nansen Basin, north of Svalbard, under the Coordinated Arctic Acoustic Thermometry Experiment (CAATEX) between September 2019 and July 2020. The data set from the CAATEX moorings provide an updated picture of the hydrography and circulation in the Nansen Basin, north of Svalbard. The main finding at the southernmost mooring, A-N2, was increased temperatures (1.75 °C) and current speeds (10 cm/s) at 50 m at the beginning of March 2020. Further north, at the C-N1 mooring, the temperature profiles between 50 m and 1000 m were quite stable throughout the year, especially between 50 m and 91 m. The calculated mean temperature of the AWL along the CAATEX section in the Eurasian Basin is well represented by the Ocean-Reanalysis Multi-Model-Mean and provides confidence in using the reanalysis to evaluate climate models in the region. The effect of salinity on sound speed was found to be small, but the vertical and horizontal distribution of salinity between regions has to be accounted for if the salinity range is large.