Shelf-edge exchange in the Labrador Sea

• Supervisors: Elodie Duyck, Eleanor Frajka-Williams
• Data: Lagrangian drifter trajectories from the Global Drifter Program
• Time period: Since 2019
• Region: Subpolar North Atlantic / Labrador Sea
• Topic: Investigating the processes responsible for shelf-edge exchange (wind and eddies), to understand how fresh shelf waters of Arctic and Greenland origin can escape to the center of the Labrador Sea/subpolar gyre.

Subtropical gyre and wind-adjustment (no longer available)

• Supervisor(s): Eleanor Frajka-Williams
• Data: Satellite altimetry and reanalysis wind, in situ transport estimates from the RAPID 26°N array.
• Time period: Primarily 2004-2022, but also from 1993.
• Region: subtropical North Atlantic
• Topic: Investigating variability of upper mid-ocean (top 1100m) and Antilles Current transports in response to wind-stress curl over the Atlantic.

Presence of small-scale (2–10km) motions in Denmark Strait overflow water

• Supervisor(s): Eleanor Frajka-Williams, Simon Wett / Joel Bracamontes Ramierez
• Data: Mooring array south of Denmark Strait
• Time period: 2012, 2017, 2018
• Region: east of Greenland, south of Iceland
• Characterising the horizontal and vertical structure of hydrographic properties (temperature, salinity) and ocean currents (velocity) in the outflow plume of the Denmark Strait overflow water.

Variability of Denmark Strait overflow water properties (no longer available)

• Supervisor(s): Eleanor Frajka-Williams
• Data: Mooring array in Denmark Strait
• Time period: 2006-2022
• Region: Denmark Strait, between Greenland and Iceland
• Evaluating the interannual variability of properties (temperature, salinity and density) of DSOW characteristics.

Small-scale eddies in the Labrador Sea

• Supervisor(s): Martin Gade, Eleanor Frajka-Williams, Emelie Breunig
• Data: Drifter trajectories OR SAR images
• Time period: 2019-21 OR recent
• Region: Labrador Sea, west of Greenland
• Characterising the presence of submesoscale eddies in the boundary currents around the Labrador Sea, and (possibly) around the convective patch in the central Labrador Sea.

Methods of measuring ocean properties (no longer available)

• Supervisor(s): Eleanor Frajka-Williams - Data: Time series from a Seabird MicroCAT and RBR Concerto measuring temperature and salinity at 2000m in the western Atlantic, and associated hydrographic data from ship-based CTD profiles - Time period: 2020-2022. - Region: western boundary of the subtropical Atlantic, near the Bahamas Diagnosing quality and pitfalls of two different sensors for measuring ocean properties.

Measuring vertical seawater velocity from ocean gliders

• Supervisor(s): Eleanor Frajka-Williams, Louis Clement (NOC) - Data: Seaglider and Slocum data from the Labrador Sea (and possibly elsewhere) - Time period: 2005-present - Region: Labrador Sea and elsewhere Marine autonomous gliders can be used to estimate vertical seawater velocities by using their measured pressure signals and comparing it to predicted vehicle depth based on a flight model for the vehicle. Several avenues of investigation are possible, including how different flight models produce different estimates of vertical velocity (and associated uncertainties) and how those vertical velocity characteristics differ in the ocean (e.g., in regions of deep convection like the Labrador Sea or western Mediterranean).