Figure 1. General bathymetric chart of the investigated area in the North Atlantic Ocean.

(a) Sampling transect of ¹²⁹I along the northeastern Atlantic Ocean. Sampling locations are expressed as blank dots. Two European nuclear reprocessing facilities (NRFs) Sellafield and La Hague, are highlighted with stars. (b) General scheme of surface water circulation in the region of Bay of Biscay and (c) the Gulf of Cadiz. NAC = North Atlantic Current, IPC = Iberian Poleward Current, PC = Portuguese Current, AC_N = Azores Current, northern branch, AC_S = Azores Current, southern branch and CC = Canary Current. The bathymetry and coastal lines were created using Ocean Data View (ODV 4.5.3).