Ocean Dynamics

, Volume 56, Issue 5–6, pp 634–649 | Cite as

Using sea-level data to constrain a finite-element primitive-equation ocean model with a local SEIK filter

  • Lars Nerger
  • Sergey Danilov
  • Wolfgang Hiller
  • Jens Schröter
Original paper


Inspired by the pioneering work of Christian Le Provost on finite element ocean modeling, a new ocean circulation model was developed over the last few years. It applies a surface triangulation and finite elements for an accurate description of coasts and bathymetry and their steering effect on the ocean circulation. A novel feature is the mesh design, which allows a vertical structure in geopotential (z) coordinates without loss of flexibility and avoids pressure gradient errors everywhere except for the lowest layer of abyssal ocean. The model is combined with sea-level measurements and data assimilation, another major research topic of Christian Le Provost. We apply the SEIK filter that was developed in Grenoble while Christian was teaching there. The addition of a local analysis scheme improves the filter performance, first of all, in its variance estimates and also in its mean solution.


Data assimilation Finite elements SEIK filter Local filter 


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Lars Nerger
    • 1
    • 2
  • Sergey Danilov
    • 2
  • Wolfgang Hiller
    • 2
  • Jens Schröter
    • 2
  1. 1.Global Modeling and Assimilation OfficeNASA Goddard Space Flight CenterGreenbeltUSA
  2. 2.Alfred Wegener Institute for Polar and Marine ResearchBremerhavenGermany

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