Sea ice dispersion mirrors underlying submesoscale ocean currentsamid strong atmospheric forcing
ORAL
Abstract
Marginal ice zones (MIZ) are important regions between the ice pack and the open ocean. Here, heat and fresh water budgets are strongly influenced by the sea ice field and vice versa. However, a full characterization of these dynamics is still lacking. Employing two decades of continuous optical satellite imagery, we present unique sea ice observations acquired during the spring and summer seasons in Arctic MIZ over the 21st century. We find that the intrinsically strong sea ice-ocean interactions drive sea ice to mirror meso/submeso-scale ocean eddies, even amid strong wind conditions. As such, the sea ice drift field serves as an indicator to gauge the evolution of MIZ dynamics in a rapidly changing Arctic. We analyze the topology of the underlying flow field in the region via one- and two-particle dispersion statistics of sea ice. We show that deviations from a mean flow are driven predominantly by energetic turbulent fluctuations. We also find an anti-correlation between sea ice extent and sea ice fluctuating velocities. This relationship provides direct observational evidence that declining sea ice concentrations have lead to enhanced turbulent activity on the ocean surface. Our results can help achieve a realistic parameterization of sea ice-turbulent ocean interactions.
*R.L. was funded by the Graduate Assistance in Areas of National Need (GAANN) program from
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Presenters
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Rosalinda Lopez
- University of California, Riverside, Department of Mechanical Engineering, Riverside, California, 92521, USA