Ventilation of the deep northeastern Atlantic

Comparison of the 1973 GEOSECS expedition results from the deep eastern basin of the North Atlantic with those for 1981 TTO expedition reveal no firm evidence for change in NO 3 , PO 4 , or a H 4 SiO 4 . concentration. While a 2–3 μmol/kg difference is seen for O 2 , it is more likely experimental than temporal in origin. The combined TTO‐GEOSECS data sets reveal no evidence for ventilation of the bottom waters of the eastern basin by waters from the north.