Rückert, Janna Elisabeth; Brechtelsbauer, Stefanie; Bühler, Linnu; Menke, Margret; Walbröl, Andreas (2026): Sea ice density and salinity profiles measured during RV POLARSTERN cruise PS149 [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.993859

During the Polarstern cruise PS149 from July 2025 to August 2025 in the Atlantic part of the Arctic Ocean, ice core samples were obtained with a 9 cm Kovacs corer during 30 ice stations. This dataset contains vertical density and salinity profiles obtained by cutting the core in 5 cm intervals (for the upper 20 cm) and 10 cm intervals for the remaining part. The samples were weighed on the ice. Together with the known volume, densities are calculated for each sample. The samples were taken to the ship, melted and their salinity was measured using a Greisinger G1410 salinometer (measuring salinity and conductivity). An intercomparison of the salinometer with two others revealed a bias, which is described in the attached PDF and corrected for in the columns "Sea ice salinity corrected [PSU]" and "Sea ice conductivity corrected [S/m]". The measured total ice, surface scattering layer (SSL) and snow thicknesses as well as the ice freeboard (distance from sea level to ice surface, the total freeboard is derived by adding the snow thickness) are included in the dataset. Note that the ice thickness and freeboard were measured in the cored hole using an ice thickness gauge. Because of that and additional uncertainties due to the cutting of the core, the summed length of the measured ice core samples and the ice thickness may differ by up to a few cm. Note that the location (latitude and longitude in the dataset) was usually measured at the start of all measurements performed by the group, while the actual coring occurred up to a few hours later and does not account for sea ice drift. The ice cores are identifiable by the column "unique core number", which is the same as used in the temperature profile dataset. In total, there are 29 cores. Usually the ice cores were taken within the footprint of the onboard microwave radiometers installed for the VAMPIRE project (t (https://doi.org/10.1594/PANGAEA.990497)) (that is, in about 25 m distance to the port bow of Polarstern), except for the ice station with event label PS149_30-1, specified further in the "Location" column. The ice stations lasted two to three days (day at station is included in the dataset), and the floes (named '1', '2', and '3') were revisited. The name of the ice floe contained in the dataset gives the number of the visit (indicated by 'a','b', 'c', and 'd') and the floe name (e.g., '2a' refers to the the first visit of floe 2). For more information of these measurements the user is referred to Chapter 3 of the cruise report.