Fig. 3: Upper North Atlantic Deep Water (UNADW) layer thickness anomalies.

a Labrador Sea: UNADW layer (σ_θ = 27.70–27.80 kg m⁻³) thickness anomalies across the full Labrador Current (LC; dark blue) and West Greenland Current (WGC; light blue) arrays (see Fig. 1b for location), respectively, with shading represents uncertainty; layer thickness anomalies in the Labrador Sea interior (red, shading represents ±1 standard deviation) computed from Argo data north of the OSNAP line where seafloor >3000 m deep (Methods). b Irminger Sea: UNADW (σ_θ = 27.55–27.80 kg m⁻³) layer thickness anomalies across the East Greenland Current (EGC) array of tall moorings within the boundary current (blue; see Fig. 1b for location), with shading represents uncertainty; layer thickness anomalies in the Irminger Sea interior (red, shading represents ±1 standard deviation) computed from Argo data north of the OSNAP line where seafloor >2000 m deep (Methods). c, d Irminger Sea: similar as in (b), but for the lightest (σ_θ = 27.55–27.73 kg m⁻³) and most dense UNADW layers (σ_θ = 27.73–27.80 kg m⁻³), respectively.