Estimates of fluxes of 137Cs in northern waters from recent measurements

Concentrations of 137Cs were determined in surface and sub-surface waters sampled in 1994, from the Norwegian Coastal Current, Norwegian Sea, Barents Sea, Fram Strait, Greenland Sea and the Iceland-Faroe Gap. Additional surface samples were taken from the Iceland-Faroe Gap in 1995. The data were compared with previous measurements from the region. Concentrations in the south-western Barents Sea continued to decline, a trend matched by the decrease in the release of reprocessing waste. The flux of 137Cs into the Barents Sea in 1994 was estimated to be 300–400 TBq, including 100–200 TBq of fallout origin. The calculations were based on both contemporaneous hydrographic observations and published transport estimates. A further 120–180 TBq of 137Cs, of non-fallout origin, was estimated to have been transported through Fram Strait into the Polar Ocean.