A meridional 14C and 39Ar section in northeast Atlantic deep water
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 distributio...
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American Geophysical Union
1985
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ftunivbern:oai:boris.unibe.ch:158710 2023-08-20T04:02:14+02:00 A meridional 14C and 39Ar section in northeast Atlantic deep water Schlitzer, Reiner Roether, Wolfgang Weidmann, Urs Kalt, Peter Loosli, Heinz Hugo 1985 application/pdf https://boris.unibe.ch/158710/1/schlitzer85jgr.pdf https://boris.unibe.ch/158710/ eng eng American Geophysical Union https://boris.unibe.ch/158710/ info:eu-repo/semantics/openAccess Schlitzer, Reiner; Roether, Wolfgang; Weidmann, Urs; Kalt, Peter; Loosli, Heinz Hugo (1985). A meridional 14C and 39Ar section in northeast Atlantic deep water. Journal of Geophysical Research: Oceans, 90(C4), pp. 6945-6952. American Geophysical Union 10.1029/JC090iC04p06945 <http://dx.doi.org/10.1029/JC090iC04p06945> 530 Physics info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed 1985 ftunivbern https://doi.org/10.1029/JC090iC04p06945 2023-07-31T22:08:19Z 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 an entire deep-ocean circulation system are presented for the first time. The observed 14C and 39Ar distributions are mutually consistent. Transit times from the source regions to the equator for water from northern and southern deepwater sources are estimated to be about 170 and 105 years, respectively, and the 39Ar concentration of young Antarctic Bottom Water is deduced as 60±7% modern. The 39Ar-14C correlation in the ocean appears to be affected by mixing of waters of different age and by more efficient raising of 39Ar in the deepwater formation processes. Article in Journal/Newspaper Antarc* Antarctic Northeast Atlantic BORIS (Bern Open Repository and Information System, University of Bern) Antarctic Journal of Geophysical Research 90 C4 6945 |
institution |
Open Polar |
collection |
BORIS (Bern Open Repository and Information System, University of Bern) |
op_collection_id |
ftunivbern |
language |
English |
topic |
530 Physics |
spellingShingle |
530 Physics Schlitzer, Reiner Roether, Wolfgang Weidmann, Urs Kalt, Peter Loosli, Heinz Hugo A meridional 14C and 39Ar section in northeast Atlantic deep water |
topic_facet |
530 Physics |
description |
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 an entire deep-ocean circulation system are presented for the first time. The observed 14C and 39Ar distributions are mutually consistent. Transit times from the source regions to the equator for water from northern and southern deepwater sources are estimated to be about 170 and 105 years, respectively, and the 39Ar concentration of young Antarctic Bottom Water is deduced as 60±7% modern. The 39Ar-14C correlation in the ocean appears to be affected by mixing of waters of different age and by more efficient raising of 39Ar in the deepwater formation processes. |
format |
Article in Journal/Newspaper |
author |
Schlitzer, Reiner Roether, Wolfgang Weidmann, Urs Kalt, Peter Loosli, Heinz Hugo |
author_facet |
Schlitzer, Reiner Roether, Wolfgang Weidmann, Urs Kalt, Peter Loosli, Heinz Hugo |
author_sort |
Schlitzer, Reiner |
title |
A meridional 14C and 39Ar section in northeast Atlantic deep water |
title_short |
A meridional 14C and 39Ar section in northeast Atlantic deep water |
title_full |
A meridional 14C and 39Ar section in northeast Atlantic deep water |
title_fullStr |
A meridional 14C and 39Ar section in northeast Atlantic deep water |
title_full_unstemmed |
A meridional 14C and 39Ar section in northeast Atlantic deep water |
title_sort |
meridional 14c and 39ar section in northeast atlantic deep water |
publisher |
American Geophysical Union |
publishDate |
1985 |
url |
https://boris.unibe.ch/158710/1/schlitzer85jgr.pdf https://boris.unibe.ch/158710/ |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Northeast Atlantic |
genre_facet |
Antarc* Antarctic Northeast Atlantic |
op_source |
Schlitzer, Reiner; Roether, Wolfgang; Weidmann, Urs; Kalt, Peter; Loosli, Heinz Hugo (1985). A meridional 14C and 39Ar section in northeast Atlantic deep water. Journal of Geophysical Research: Oceans, 90(C4), pp. 6945-6952. American Geophysical Union 10.1029/JC090iC04p06945 <http://dx.doi.org/10.1029/JC090iC04p06945> |
op_relation |
https://boris.unibe.ch/158710/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/JC090iC04p06945 |
container_title |
Journal of Geophysical Research |
container_volume |
90 |
container_issue |
C4 |
container_start_page |
6945 |
_version_ |
1774712632900583424 |