A meridional 14C and 39Ar section in northeast Atlantic deep water ...

• Main Authors: Schlitzer, Reiner, Roether, Wolfgang, Weidmann, Urs, Kalt, Peter, Loosli, Heinz Hugo
• Format: Text
• Language: unknown
• Published: American Geophysical Union 1985
• Subjects: 530 Physics; Northeast Atlantic
• Online Access: https://dx.doi.org/10.48350/158710; https://boris.unibe.ch/158710/

14C, 39Ar, and complementary hydrographic and nutrient data are presented for deep water below 2500 m depth, from stations along a meridional section (8°S to 45°N) through the Romanche Trench and along the deep northeast Atlantic basins (F/S Meteor, cruise 56, leg 5). The large-scale 14C distribution along the section is resolved at the 14C data precision of ±2‰. Bottom water Δ14C decreases by 6‰ from the equator to 45°N, and farther up there is a weak Δ14C minimum (−123‰) over much of the section. The 14C data are interpreted as giving a turnover time of about 30 years for the waters below the depth of the 14C minimum (∼4250 m). It is found that water of 1.50±0.05°C potential temperature enters the East Atlantic from the west through the Romanche Trench (sill depth about 4000 m), and a preliminary value for the inflow rate of 3.6×106 m3/s is deduced. This rate greatly exceeds estimated deep inflow rates through the Vema fracture zone or across the northern boundary of the East Atlantic. 39Ar data that cover ...