During the Polarstern cruise PS131 photos of the surface (open ocean and sea ice) were recorded from onboard the vessel with a down-looking camera (GoPro Hero 9 Black) 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°. Each image has a size of 5184 × 3888 pixels. The images are stored as zipped JPG files where one zip file includes data from one hour. The visual camera was operated in conjunction with an infrared camera, pointing at the same target, in addition, microwave radiometers measured the surface brightness temperatures of a small area within the camera image. From 11 July, 00:52 UTC, the cameras was operated with a sampling rate of 0.2 Hz, taking a picture every 5 s. Data is missing from 17 July, 8:52 to 18 July, 7:05, on 25 July from 16:55 - 18:13, from 31 July, 10:16 to 1 August, 10:52, and from 2 August, 8:20 to 3 August, 9:42.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).
File descriptions: Zip files with JPG files. Metadata of the JPG files includes GPS date/time which was used to name the file according to the date and time. For cases with no GPS data (marked by ending with no_GPSdata.JPG) the time in the name of the file is taken from the internal camera timestamp which may deviate from the GPS timestamp by up to 4 seconds. internal software issues falsely shifted the timestamp of every 12th image by 1 minute in cases with no GPS which was confirmed by visual inspection and corrected during the naming of the files. The filename therefore contains the corrected timestamp .