A new study supported by ObsSea4Clim and EuroGO-SHIP has been published in the Journal of Physical Oceanography focuses on describing mesoscale eddies in the Labrador Sea based on ship observations. 

The characterization of coherent eddies is often based on gridded satellite altimetry products. In subpolar regions, these products face limitations due to their low spatial resolution and the decreasing Rossby radius of deformation at higher latitudes, making in situ observations indispensable for eddy characterization. Here, we present a census of mesoscale-to-submesoscale eddy characteristics in the Labrador Sea—a region where eddies play an important role in winter deep convection and subsequent restratification. Using ship-based observations, we fit an idealized eddy solution to horizontal velocity measurements acquired along ship tracks, determining an optimal eddy center and other key eddy properties. Based on three research cruises, we reconstructed 40 eddies ranging from 3 to 39 km in radius (mean 15 km) and azimuthal velocity between 7 and 58 cm s⁻¹ (mean 26 cm s⁻¹). The azimuthal velocity structure implies to a large extent solid-body rotation in the eddy’s inner core, while opposite signs of vorticity in the outer ring suggest strong vorticity shields. When compared to ship-based observations, the eddy field representation in gridded altimetry products is significantly distorted, with many eddies being underrepresented or undetected. This is even the case for larger-scale features despite having an eddy signature in the along-track altimetry product, which appears to be suppressed in the subsequent mapping methodology. Finally, comparisons with submesoscale-permitting numerical simulation output show favorable agreement giving confidence in both the ship-based reconstruction and the numerical model’s realism in representing high-latitude eddy dynamics.

The full article is available here:

Bendinger, A., A. F. Dilmahamod, A. Albert, J. Le Sommer, and J. Karstensen, 2025: Characteristics of Mesoscale-to-Submesoscale Eddies in the Labrador Sea: Insights from Ship Observations. J. Phys. Oceanogr., 55, 2037–2057, https://doi.org/10.1175/JPO-D-24-0216.1.