The MOSAiC Drift: Ice conditions from space and comparison with previous years

• Main Authors: Krumpen, Thomas, Albedyll, Luisa, Goessling, Helge F., Hendricks, Stefan, Juhls, Bennet, Spreen, Gunnar, Willmes, Sascha, Belter, H. Jakob, Dethloff, Klaus, Haas, Christian, Kaleschke, Lars, Katlein, Christian, Tian-Kunze, Xiangshan, Ricker, Robert, Rostosky, Philip, Rueckert, Janna, Singha, Suman, Sokolova, Julia
• Format: Text
• Language: English
• Published: 2021
• Subjects: Laptev Sea; Fram Strait; Kara-Laptev; laptev; Sea ice
• Online Access: https://doi.org/10.5194/tc-2021-80; https://tc.copernicus.org/preprints/tc-2021-80/

We combine satellite data products to provide a first and general overview of the sea-ice conditions along the MOSAiC drift and a comparison with previous years. We find that the MOSAiC drift was around 25 % faster than the climatological mean drift, as a consequence of large-scale low-pressure anomalies prevailing around the Barents-Kara-Laptev Sea region between January and March. In winter (October–April), satellite observations show that the sea-ice in the vicinity of the Central Observatory (CO) was rather thin compared to the previous years along the same trajectory. Unlike ice thickness, satellite-derived sea-ice concentration, lead frequency, and snow thickness during winter month were close to the long-term mean with little variability. With the onset of spring and decreasing distance to Fram Strait, variability in ice concentration and lead activity increased. In addition, frequency and strength of deformation events (divergence and shear) were higher during summer than during winter. Overall, we find that sea-ice conditions observed close (~ 5 km) to the CO are representative for the wider (50 km and 100 km) surroundings. An exception is the ice thickness: Here we find that sea-ice near the CO (50 km radius) was 4 % thinner than sea-ice within a 100 km radius. Moreover, satellite acquisitions indicate that the formation of large melt ponds began earlier on the MOSAiC floe than on neighbouring floes.