Arctic sea ice freeboard during summer – a new Cryo-TEMPO product

Arctic sea ice thickness impacts various physical and biogeochemical processes at the air-ice-ocean interface. For example, it determines how much sunlight reaches the base of the ice – a key parameter for primary production. It is also an essential variable for sea ice forecasts, shipping and other marine activities. During the summer months (May-September) melt ponds complicate the retrieval of sea ice thickness compared to winter. On the other hand, summer sea ice thickness observations are particularly important as this is when most shipping and biological production happen. Summer sea ice thickness estimates are also crucial to extend predictions by many months.

In this study, we present the novel summer sea ice Cryo-TEMPO product. Cryo-TEMPO is a set of easily accessible thematic products derived from CryoSat data targeted at both expert and non-expert users. The summer sea ice product contains freeboard measurements and smoothed freeboard, which are calculated at each lead position along the altimetry tracks. The product covers the whole Arctic and the full CryoSat lifetime since 2010. It will be updated operationally from summer 2024 onwards. Comparisons against various airborne and mooring data were conducted for validation and will be presented, too.