Overflow '73

During the ICES Expedition Overflow '73, which had a core period of observation between 15 August and 15 September 1973, there was, for the first time, an opportunity to investigate synoptically the details of the ocean circulation between Greenland and Scotland. This area had hitherto attracted considerable attention because it was believed to be the scene of the exchange of warm saline Atlantic waters with the colder and less saline waters of the Norwegian Sea. The Project was designed as a follow up to Overflow '60.

One of the principal objectives of Overflow '73 was to describe in detail the kinematic and dynamic processes which leads to the renewal, by 'shoves' of the sub-Arctic bottom water of the northern North Atlantic across the Iceland-Faroe Ridge and the steadier renewals known to occur in the Denmark Strait and the Faroe-Shetland and Faroe-bank Channels. During the expedition more that 1700 serial hydrochemical/CTD stations were worked, and 52 current meter moorings were deployed and recovered. In addition numerous anciliary measurements were made, including XBTs, tide measurements and drogue tracking. More information may be obtained from the Overflow 73 chief scientist (Prof J. Meincke - meincke@meer.ifm.uni-hamburg.de ) or the ICES Oceanography Secretary.

At the end of August 1973 many of the Research Vessels taking part in the project had various parties in Thorshavn, Faroe Islands. One of these took place on the "Explorer" during which a special cake for the occasion was consumed.

The Overflow '73 dataset is freely available as a compressed comma separated file.

Details of the Oceanographic Profile data collected as a contribution to Overflow '73 are given below:

IOCShipDate# of Bottles# of CTD's# at ICES
18Hudson02 Aug to 26 Sep 73200203198
26Dana26 Jul to 09 Sep 7361 58#
26J.C. Svabo15 Aug to 25 Aug 7327 27#
06Meerkate 208 Aug to 22 Sep 7312170
06Meteor11 Aug to 21 Sep 734619843#
06Walther Herwig09 Aug to 05 Sep 7388159154#
06Walther Herwig08 Sep to 30 Sep 73214116
46Bjarni Saemundsson14 Aug to 06 Sep 73108 108
58Helland-Hansen15 Aug to 05 Sep 73132 132
74Challenger21 Aug to 14 Sep 7322163163#
74Cirolana13 Jul to 26 Jul 738x8#
74Explorer14 Aug to 16 Sep 7395 95
74Shackleton07 Aug to 15 Sep 7319187
90Boris Davydov14 Aug to 13 Oct 73707061