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On Oceanic Boundary Conditions for Tritium, on Tritiugenic 3He, and on the Tritium-3He Age Concept

  • Wolfgang Roether
Part of the NATO ASI Series book series (ASIC, volume 284)

Abstract

Time dependence of tracer boundary conditions is a critical item in oceanic modelling of transient tracer data. For tritium, delivery to the ocean has occurred by flux imposed from the atmosphere, and both a flux and a concentration surface-ocean boundary condition can be formulated. Previous accounts of these are out lined, and ways to obtain boundary conditions needed in a given modelling context are suggested. 3He from tritium decay allows tritium-3He ‘dating’, and this approach largely circumvents the tracer boundary condition problem. However, the tritiugenic component of oceanic 3He is small, so that its separation from the natural 3He background can pose problems. The lowest achievable error in determining tritiugenic 3He is about ± 0.04 TR (one Sigma); this limit is related to availability of high-precision helium and neon data. The transport equation for tritium-3He age is explored and compared with that for regular transient tracers. A tendency of age distributions to develop towards stationarity is found. A case is made that tritium-3He age distributions are suitable for evaluation by inverse modelling. The case is discussed for tritium-3He age distributions in the lower main thermocline of the Northeast Atlantic, and aspects requiring further attention are noted.

Keywords

Ocean Surface Potential Vorticity Inverse Modelling Solubility Equilibrium Vertical Advection 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • Wolfgang Roether
    • 1
  1. 1.Universität BremenBremen 33Germany

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