Large Mesoscale Eddy Properties and Dynamics in the Labrador Sea from Satellite Altimetry

Oceanic mesoscale eddies are crucial and active players in the lateral and vertical transport and mixing of heat, salt, and momentum in the Labrador Sea. Our study employs the Mesoscale Eddy Trajectory Atlas (META) product based on satellite altimetry to conduct a comprehensive statistical investigation into the eddy landscape in the Labrador Sea (48–62∘W, 54–64∘N), including its variability, spatial distribution and characteristics distribution. Our study over 2005–2020 provides a quantitative study of the eddy number based on its type, lifespan, and geographical location in the Labrador Sea. It also depicts the spatial distribution and trajectory distinctions between the anticyclones and cyclones, accompanied by a detailed demonstration of eddy characteristics probability distribution. Furthermore, our findings affirm the prevailing nonlinearity of the majority of eddies in the Labrador Sea. They are important carriers of freshwater and heat from the Greenland coast to the Labrador Sea interior. The sea ice variability is tightly correlated with the eddy distribution on the western shelf of the Labrador Sea on both the seasonal and interannual time scales and mainly dampens anticyclone generation in this area. Lastly, utilizing the Multi Observation Global Ocean ARMOR3D, a 3D gridded observationally-based dataset, we conduct a case study of a long-lasting cyclonic eddy by extracting its thermohaline properties and computing its vertical heat flux. The case study underscores the profound impact of this cyclone on vertical heat transport within the marginal ice zone, with its intensity potentially linked to local wind forcing. These findings offer valuable insights into the properties of large mesoscale eddies detected in satellite altimetry, their roles in transporting heat, and their mutual interactions with sea ice in the climatically sensitive Labrador Sea.