“Ice-Track”: Providing High-Resolution Sea Ice Type Forecast for Route Optimization

Kurzfassung

Spaceborne Synthetic Aperture Radar (SAR) images are well suited for navigation assistance through ice covered waters due to their all-day and all-weather capability. For Arctic campaigns of RV Polarstern, SAR images are acquired and automatically delivered onboard. However, at the time of delivery the surrounding ice fields have already drifted and the SAR scenes need to be moved manually to fit to the current ice situation surrounding the ship. This hinders the direct application of SAR scenes to route planning. We aim to enable automatic route planning through drifting sea ice. For this, high-resolution sea ice type maps from TerraSAR-X and Sentinel-1 SAR images (Kortum et al., 2022; Murashkin and Frost, 2021) are advected, using the sea ice drift forecast models TOPAZ (Sakov et al., 2012) and neXtSIM (Rampal et al., 2016) on a Lagrangian coordinate system (Bathmann et al., 2023). We perform a quality check in Winter 2022 / 2023 on the sea ice drift forecast models TOPAZ4 and neXtSIM that are provided by the Copernicus Marine Environmental Monitoring Service (CMEMS). Additionally, we compare our results with the current version of TOPAZ5 and neXtSIM-F available on CMEMS since Winter 2023 / 2024. The obtained information is applied as input data for an algorithm that optimize route suggestions through sea ice in the Arctic, which we are currently developing. We report on the experiences obtained on RV Polarstern with this new data product on its expedition PS144 in August 2024 to the Central Arctic and present feedback from first-hand experience on board