Description: A newly developed method to derive melt pond bathymetry from aerial images allowed us to compile spatially fully resolved maps of pond depth on the MOSAiC floe from three measurement flights on 30 June, 17 July, and 22 July 2020. The pond bathymetry maps provide an unprecedented comprehensive insight into the spatial and temporal development of ponds and their geometry. They were derived to better understand pond evolution, determine the volume of water contained in the ponds, and eventually obtain improved parameterizations for ponds. The data is provided in GeoTIFF raster format, with every pixel in ponds containing the depth at that location in meters, downward negative. Pond bathymetry was calculated from orthomosaics and digital elevation models processed from helicopter aerial images collected on MOSAiC floe grid surveys. Pond bathymetry is stored in GeoTIFFs, containing pond depth in meters, in the negative downward direction. Only regions classified as ponds with the classification algorithm PASTA-ice are included. Some pond-like objects on the floe were classified as submerged ice/open water due to their visual appearance or connection to the floe edge and are therefore not included. The raster data is projected in WGS 84 / NSIDC Sea Ice Polar Stereographic North (EPSG:3413). It was derived from the orthomosaics and DEMs presented in doi:10.1594/PANGAEA.949433 and can therefore be overlaid directly with this data.

Description: During the MOSAiC expedition, a comprehensive aerial observation program was conducted by the helicopters of the R/V Polarstern. This dataset contains two GeoTiff orthomosaics compiled from aerial RGB images recorded during Leg 4 above the central observatory (CO) on 2020-06-30 and 2020-07-22 and derived surface type classes maps on the leg 4 floe stored in shape file format. The data was processed based on the workflow presented in: https://gitlab.awi.de/nifuchs/pasta-ice. Both orthomosaics were overlaid with the position of the leg 4 floe on 2020-06-30 to facilitate comparison between both. The data is projected to UTM31N (EPSG: 32631) and resampled to a resolution of 0.5m. The aim of this dataset was to retrieve melt pond fraction on the leg 4 floe and give a visual identification for pond locations on both dates.

Description: The Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition took place between October 2019 and September 2020 giving the rare opportunity to monitor sea-ice properties over a full annual cycle. Here we present 24 high-resolution orthomosaics and 14 photogrammetric digital elevation models of the sea-ice surface around the icebreaker RV Polarstern between March and September 2020. The dataset is based on 〉34.000 images acquired by a helicopter-borne optical camera system with survey flights covering areas between 1.8 and 96.5 km^2 around the vessel. Depending on the flight pattern and altitude of the helicopter, ground resolutions of the orthomosaics range between 0.03 and 0.5 m. By combining the photogrammetric products with contemporaneously acquired airborne laser scanner reflectance measurements selected orthomosaics could be corrected for cloud shadows which facilitates their usage for sea-ice and melt pond classification algorithms. The presented dataset is a valuable data source for the interdisciplinary MOSAiC community building a temporal and spatially resolved baseline to accompany various remote sensing and in situ research projects. Central Observatory (CO) grid flights are available as single grids while transect and triangle flights were segmented into 2 km x 2 km data tiles to provide the user with manageable file sizes. Next to the orthomosaic and DEM data we provide confidence maps of the respective survey flights. All data is stored in GeoTIFF file format and gridded to 0.5 m spatial resolution. For the CO grid flights we also provide orthomosaic data at full spatial resolution within a 3 km square centered at Polarstern. The naming convention of the final data products is: Date, #Flight, DShip ID, followed by DEM, confidence or orthomosaic, and hr for high resolution (0.5 m) or fr for full resolution. As we provide brightness corrected orthomosaics these are termed l2 for level 2 products and if the data were corrected for the effect of cloud shadows we added a l2b product. All datasets were projected to a polar stereographic reference system centered at 45° W and vertically referenced to the Global Mean Sea Surface grid provided by DTU Space. The final datasets are stored in one zip archive per survey flight.

Description: The data contains upward broadband irradiance, as well as attitude corrected and uncorrected downward irradiance measurements that were performed during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) experiment between June and September 2020. Research flights were conducted by helicopter and the helicopter-borne probe HELiPOD. Measurements were taken by CMP22 broadband pyranometers (210-3600 nm). The data includes the attitude and geographic location of the helicopter/HELiPOD in a 10 Hz temporal resolution.

Description: Data include area fractions of sea ice surface types (white ice/snow, bright melt ponds, dark melt ponds, open water, bare ice) obtained from aerial imagery during 29 research flights that were performed within the scope of the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC) experiment from May 2020 until end of September 2020. The images were taken every four seconds by fisheye lens cameras (Canon EOS digital) installed on a helicopter or HELiPOD, a towed survey probe. The data set provides additional information about the attitude and geographic location of the helicopter/HELiPOD. Only images that passed the quality checks were included.

Description: Data include area fractions of sea ice surface types (white ice/snow, bright melt ponds, dark melt ponds, open water, bare ice) obtained from aerial imagery during 29 research flights that were performed within the scope of the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC) experiment from May 2020 until end of September 2020. The images were taken every four seconds by fisheye lens cameras (Canon EOS digital) installed on a helicopter or HELiPOD, a towed survey probe. The data set provides additional information about the attitude and geographic location of the helicopter/HELiPOD. Only images that passed the quality checks were included.

Description: Data include area fractions of sea ice surface types (white ice/snow, bright melt ponds, dark melt ponds, open water, bare ice) obtained from aerial imagery during 29 research flights that were performed within the scope of the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC) experiment from May 2020 until end of September 2020. The images were taken every four seconds by fisheye lens cameras (Canon EOS digital) installed on a helicopter or HELiPOD, a towed survey probe. The data set provides additional information about the attitude and geographic location of the helicopter/HELiPOD. Only images that passed the quality checks were included.

Description: The data contains upward broadband irradiance, as well as attitude corrected and uncorrected downward irradiance measurements that were performed during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) experiment between June and September 2020. Research flights were conducted by helicopter and the helicopter-borne probe HELiPOD. Measurements were taken by CMP22 broadband pyranometers (210-3600 nm). The data includes the attitude and geographic location of the helicopter/HELiPOD in a 10 Hz temporal resolution.

Description: The data contains upward broadband irradiance, as well as attitude corrected and uncorrected downward irradiance measurements that were performed during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) experiment between June and September 2020. Research flights were conducted by helicopter and the helicopter-borne probe HELiPOD. Measurements were taken by CMP22 broadband pyranometers (210-3600 nm). The data includes the attitude and geographic location of the helicopter/HELiPOD in a 10 Hz temporal resolution.

Description: The data contains upward broadband irradiance, as well as attitude corrected and uncorrected downward irradiance measurements that were performed during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) experiment between June and September 2020. Research flights were conducted by helicopter and the helicopter-borne probe HELiPOD. Measurements were taken by CMP22 broadband pyranometers (210-3600 nm). The data includes the attitude and geographic location of the helicopter/HELiPOD in a 10 Hz temporal resolution.