Conductivity, temperature and depth (CTD) measurements during the CACOON cruises in 2019 in the Lena Delta region

This data set includes measurement during the CACOON 2019 expeditions (Fuchs et al., 2021; Strauss et al., 2021) in the Lena Delta region in Siberia. The data collection took place during two field campaigns; the first one was in March-April 2019, the second one in August 2019. Measurements were taken with a handheld SontekTM CastAway sensor with an integrated GPS. The measured data include pressure (dbar; accuracy: 0.25%), depth (m; ±0.25%), temperature (°C; ±0.05°C), conductivity (mS/cm; 0.25%±0.005 mS/cm), specific conductance (mS/cm; 0.25%±0.005 mS/cm), salinity (practical salinity scale; ±0.1), sound velocity (m/s; ±0.15 m/s), and density (kg/m3; ±0.02 kg/m3). In total, 31 depth profiles were measured from the Sardakhskaya main river channel in the Lena Delta to 80 km offshore in the Laptev Sea to specifically target the mouth area of the Sardakhskaya channel. The CTD was lowered from water surface with an additional ballast to make sure the small CTD device reached the sea (or river) bed. The data consists of two data sheets. The first one (CTD cast locations in the Lena Delta region) includes detailed data about the locations and time of CTD measurements; the second data sheet (CTD measurements in the Lena Delta region) includes the CTD data from all the measured locations.