Actual deep circulation
Trace bottom water flow by geochemical tracers
- AOU = saturation oxygen content - measured oxygen content; larger numbers mean less oxygen
- Delta 14C = ratio of 14C/12C; more negative numbers mean less 14C relative to 12C
North Atlantic Bottom Water
- Distinct bottom water masses form in Labrador Sea, Greenland Sea, & Norwegian Sea
- Eastern water mass flows south, crosses mid-Atlantic ridge at Gibbs fracture zone to join other two masses
- Flow south along west side of Atlantic, cross equator, and turn east joining deep water masses formed off Antarctica
Antarctic Bottom Water
- Forms off Antarctica, particularly in the Weddell Sea