IMIS | Flanders Marine Institute

Flanders Marine Institute

Platform for marine research


Publications | Institutes | Persons | Datasets | Projects | Maps
[ report an error in this record ]basket (0): add | show Printer-friendly version

Diagnosing ocean tracer transport from Sellafield and Dounreay by equivalent diffusion and age
Orre, S.; Gao, Y.; Drange, H.; Deleersnijder, E. (2008). Diagnosing ocean tracer transport from Sellafield and Dounreay by equivalent diffusion and age. Adv. atmos. sci. 25(5): 805-814.
In: Advances in Atmospheric Sciences. China Ocean Press/Springer: Beijing. ISSN 0256-1530, more
Peer reviewed article  

Available in  Authors 

Author keywords
    equivalent diffusion; passive tracers; age tracers; sellafield; dounreay

Authors  Top 
  • Orre, S.
  • Gao, Y.
  • Drange, H.
  • Deleersnijder, E., more


    A simple approach for estimating the equivalent diffusion for diagnosing tracer transport is proposed. Two different expressions are derived; one is based directly on an analytical solution of the two-dimensional advection-diffusion equation, the other uses the variance of the tracer distribution. To illustrate some features of the equivalent diffusion and possible applications thereof, idealized releases of passive tracers from the nuclear fuel reprocessing plants at Sellafield in the Irish Sea and Dounreay on the northern coast of Scotland have been simulated with a regional isopycnic co-ordinate Ocean General Circulation Model. Both continuous and pulse releases are considered; the former being representative of the actual historical discharges from the reprocessing plants, the latter resembling an accidental scenario. Age tracers are included to calculate the mean time elapsed since the tracers left their source regions. It is found that in the Nordic Seas the age of tracers from Dounreay is approximately 2 years younger than the age from Sellafield. Although tracers from both sources eventually end up along the same transport routes, significant qualitative differences regarding the dispersion properties are found. It is argued that one single parameter, the equivalent horizontal diffusion, which is estimated to be in the range of 20–56 m2 s-1 from Sellafield and 170–485 m2 s-1 from Dounreay, determines these differences.

All data in IMIS is subject to the VLIZ privacy policy Top | Authors