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Assimilation of XBT Data Using a Variational Technique

  • J. Sheinbaum
  • D. L. T. Anderson
Part of the NATO ASI Series book series (ASIC, volume 284)

Abstract

For several years meteorologists have used different statistical techniques to combine model and observations to obtain a good analysis of the atmospheric state. One of the most successful and widely used methods in operational weather centres is optimal interpolation, denoted OI (Gandin, 1965; Lorenc, 1986; Hollingsworth, 1987), whereby one tries to minimize the mean square error between the truth state and the analysed state of the system at a given time. This is attempted by constructing an analysis which is a linear combination of a priori field plus the weighted sum of the observational deviations from this preliminary field. Operationally, a short range forecast constitutes the preliminary field. Constraints on the time evolution of the system are not imposed, since O.I. (as currently used) is an analysis at a single time.

Keywords

Lagrange Multiplier Wind Stress Conjugate Gradient Algorithm Adjoint Method Thermocline Depth 
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

  • J. Sheinbaum
    • 1
  • D. L. T. Anderson
    • 1
  1. 1.Hooke Institute for Atmospheric Research and Department of Atmospheric, Oceanic and Planetary PhysicsClarendon LaboratoryOxfordUK

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