Raw physical oceanography data was acquired by a ship-based Seabird SBE911plus CTD-Rosette system onboard RV POLARSTERN during research cruise PS132. The CTD was equipped with duplicate sensors for temperature (SBE3plus) and conductivity (SBE4). Additional sensors such as an oxygen sensor (SBE43), a WET Labs C-Star transmissometer, a WET Labs ECO-AFL fluorometer (FLRTD) and an altimeter (Teledyne Benthos PSA-916) were mounted to the CTD. During this cruise issues with the ECO-AFL fluorometer and the C-Star transmissometer were faced. Cables and sensors were changed several times but the issue remained. Chlorophyll as well as beam transmission values should be treated with extreme care. The data was recorded using pre-cruise calibration coefficients (possibly wrong coefficients for the ECO-AFL fluorometer and the C-Star transmissometer). No correction, post-cruise calibration or quality control was applied. Text files containing bottle-Data were created using SBEDataProcessing steps "Data Conversion" and "Bottle Summary" without applying any correction.
Raw data acquired by two SBE21 thermosalinograph and two auxiliary SBE38 temperature sensor (Sea-Bird Scientific, USA) installed in an underway seawater flow-through system on board RV Polarstern were processed to yield a calibrated and validated data set of temperature and salinity along the cruise track. Data were downloaded from DAVIS SHIP data base (https://dship.awi.de) at a resolution of 1 sec, and converted to temperature and conductivity using the pre-deployment factory calibration coefficients. The converted data were averaged to 1 min values, outliers were removed, and sensor drift was corrected using coefficients obtained from a post-season calibration performed at Sea-Bird at the end of the measurement season. Salinity was calculated from internal temperature, conductivity and pressure according to the PSS-78 Practical Salinity Scale. Processed data are provided as 1 min means of seawater temperature, conductivity and salinity, aligned with position data taken from the master track. Quality flags are appended according to the SeaDataNet Data Quality Control Procedures (version from May 2010). More details are described in the attached processing report.
During the Polarstern cruise PS131 infrared (IR) brightness temperatures of the surface (open ocean and sea ice) were recorded from onboard the vessel with a down-looking infrared camera (Infrared VarioCAM HDx head camera from InfraTec) that was installed on starboard on the upper deck (at around 21.5 m from sea level ('Peildeck')). The viewing angle (off-nadir) was around 70° and the camera has a field of view of 57.1° × 44.4°. Each image has a size of 640 × 480 IR pixels. The images are stored as netCDF files where one file includes data from one day. For each image, latitude and longitude information are included. They are obtained from the mastertrack of the ship (doi:10.1594/PANGAEA.950999). In addition the dataset contains the viewing angle for each image obtained from an auxiliary inertial measurement unit (IMU) installed on the IR camera that was resampled to 2 seconds. Missing data of the IMU was filled by the average of the existing angle measurements of the respective day or, if that was not available, by a fill-value of 70°.
The IR camera was operated in conjunction with a visual camera, pointing at the same target.
The IR camera data was recording one image every 10 minutes from 3 July - 10 July. From 10 July, 16:00 UTC, the cameras was operated with a sampling rate of 0.2 Hz, taking a picture every 5 s. Data is missing on 24 July from 7:09-19:22 and on 7 August from 17:16-21:20 when the recording was stopped.
The images contain open ocean as well as sea ice in the eastern Fram Strait, the marginal ice zone in Fram Strait, during the transit to the Aurora vent field (high ice concentration) and near East Greenland (fast ice).