Kara Sea Project

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Kara Sea Project


Actual radioactivity data from the Northern Atlantic and the Arctic Ocean

During the project, an intense monitoring was carried out to measure the present levels of artificial radioactivity in the Arctic Seas.The measurements can be separated into two categories:
  1. Tracing of Sellafield derived radionuclides during cruise 261 with R/V GAUSS to the North Sea, Norwegian Sea, Barents Sea and Greenland Sea from 15 June to 27 July 1995;
  2. Analyses of sediment and water samples taken in the Kara sea and near the Kola peninsula, in order to trace any potential releases or pollution originating from dumped wastes.

The Water samples taken in the North Sea showed varying Caesium 137 activities between 3.1 and 25.5 Bq/m3.                               

The cruise track of R/V GAUSS followed the well-known transport pattern of contaminated water from the North Sea to Arctic areas. The Water samples taken in the North Sea showed varying 137Cs activities between 3.1 and 25.5 Bq/m3. The maximum concentrations above 20 Bq/m3 are located in the Skagerrak due to the continuous outflow from the Baltic Sea. Nevertheless, the dominant source of radioactivity in the North Sea are the discharges at Sellafield reprocessing plant (UK) into the Irish Sea. The present "background" concentration of surface water in the northern hemisphere originating from the global weapon test fallout is estimated to be between 2 and 3 Bq/m3. The observed concentrations in the Greenland Sea, Norwegian Sea and Barents Sea are in this range. Water samples near the Norwegian coast show slightly enhanced activity up to 8.6 Bq/m3 decreasing in northern direction reflecting the water mass transport from the North Sea into the Arctic. Samples taken near the wreck of the 'Komsomolets' show no sign of contamination from the reactor. Some higher, but not alarming activities are found in coastal waters of the Murmansk region (8 Bq/m3), where the largest part of the russian nuclear fleet is situated. The values suggest some smaller release of radioactivity from nuclear facilities.

In short, historically and currently the reprocessing plant of Sellafield is the most important source for radioactivity in the observed areas. Maximum releases from Sellafield occurred in 1975 and have significantly been reduced since that time. At the Moment, these results conclude that there is no danger to the ecosystem or to people indirectly through fish consumption. Significant outflow of radioactivity from dumped objects that may affect the Kara sea has not been observed.


1 Bq = 1 Becquerel = 1 decay per second


 © 2016 Bundesamt für Seeschifffahrt und Hydrographie Last Update: Apr 19, 2013 6:02:20 PM  
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