PANGAEA_995225 Visual images of the surface taken by a camera installed on RV POLARSTERN during expedition PS149 (July - September 2025, CONTRASTS) Bühler, Linnu; Rückert, Janna Elisabeth; Walbröl, Andreas; Krobot, Pavel Visual images of the surface taken by a camera installed on RV POLARSTERN during expedition PS149 (July - September 2025, CONTRASTS) 2026-06-17 PANGAEA Dataset https://doi.pangaea.de/10.1594/PANGAEA.995225 Investigator Linnu Bühler l.buehler@uni-koeln.de Earth Science DATE/TIME Image Image (File Size) geoscientificInformation Arctic Arctic Ocean Camera observations Digital Camera, GoPro PS149 PS149_0_Underway-16-gopro_uoc-01 RGB Sea ice Digital Camera, GoPro Polarstern 2025-07-03 2025-08-28 Complete 78.25511 81.889001 -10.085402 14.923443 AC3 Arctic Amplification unrestricted CC-BY-4.0: Creative Commons Attribution 4.0 International English PANGAEA Data Publisher for Earth & Environmental Science https://www.pangaea.de/ Data Center Contact Michael Diepenbroek info@pangaea.de

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Bremen Bremen 28359 Germany online 2503 data points text/tab-separated-values Bühler, Linnu; Rückert, Janna Elisabeth; Walbröl, Andreas; Mech, Mario; Krobot, Pavel; Ebell, Kerstin; Schnitt, Sabrina; Spreen, Gunnar (2026): Water vapor, mixed-phase clouds, precipitation and sea ice emissivity over the Central Arctic Ocean (VAMPIRE-2): remote sensing and in-situ measurements suite during POLARSTERN cruise PS149 (CONTRASTS) [dataset bibliography]. PANGAEA, https://doi.org/10.1594/PANGAEA.990497 Nicolaus, Marcel (2025): Master track of POLARSTERN cruise PS149 in 1 sec resolution (zipped, 221 MB) [dataset]. Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, PANGAEA, https://doi.org/10.1594/PANGAEA.987132

During the Polarstern cruise PS149 from July 2025 to September 2025 in the Arctic Ocean, photos of the surface (open ocean and sea ice) were recorded from onboard the vessel with a down-looking camera (GoPro Hero 11 Black) that was installed on port side on the A-deck (at around 20 m above sea level). The viewing angle (off-nadir) was around 53°. Each image has a size of 1114 x 974 pixels. The camera was operated with a sampling rate of 0.5 Hz, taking a picture every 2 s. 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 (these datasets are also part of the VAMPIRE-2 dataset bibliography https://doi.org/10.1594/PANGAEA.990497). The images are downscaled to reduce storage needs and stored as zipped JPG files where one zip file includes one image per minute from one hour. In addition, the images are projected to the ground (top view projection). For that, the ship railing visible in the lower right of each image is masked out, except for a 40 by 40 pixel area showing the white ship hull. This area may be taken as white reference (calibration target) by users who want to use, for example, calibrated brightness information. The projection to the ground uses the roll and tilt angles obtained from the hydrins measurements (available via dship at 1 Hz resolution) and the python package cameratransform with the following parameters: sensor size 6.47mm x 5.05mm and focallength_mm 3.8 mm. Finally the images are cropped to contain a smaller area in the center of the original image. These post-processed images are available in the original temporal resolution. Data is available starting 3 July, 11:06, until 28 August, 13:44. More than 1 hour of data is missing from 2025-07-03 15:17:26 to 2025-07-04 17:42:43, and from 2025-07-14 09:02:58 to 2025-07-15 08:43:10. ** For all details see the full metadata description at "https://doi.pangaea.de/10.1594/PANGAEA.995225"!

http://en.wikipedia.org/wiki/ISO_8601 DATE/TIME https://doi.org/10.17815/jlsrf-3-163 Polarstern https://doi.pangaea.de/10.1594/PANGAEA.987132 Master track of POLARSTERN cruise PS149 in 1 sec resolution (zipped, 221 MB) https://doi.pangaea.de/10.1594/PANGAEA.990497 Water vapor, mixed-phase clouds, precipitation and sea ice emissivity over the Central Arctic Ocean (VAMPIRE-2): remote sensing and in-situ measurements suite during POLARSTERN cruise PS149 (CONTRASTS) https://gepris.dfg.de/project/268020496 AC3 DIF 9.4 2026-06-17 2026-08-11