Vector Splines on the Sphere, with Application to the Estimation of Vorticity and Divergence from Discrete, Noisy Data

  • Grace Wahba

Abstract

Vector smoothing splines on the sphere are defined. Theoretical properties are briefly alluded to. An approach to choosing the appropriate Hilbert space norms to use in a specific meteorological application is described and justified via a duality theorem. Numerical procedures for computing the splines as well as the cross validation estimate of two smoothing parameters are given. A Monte Carlo study is described which suggests the accuracy with which upper air vorticity and divergence can be estimated using measured wind vectors from the North American radiosonde network.

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Copyright information

© Birkhäuser Verlag Basel 1982

Authors and Affiliations

  • Grace Wahba
    • 1
  1. 1.Department of StatisticsUniversity of Wisconsin-MadisonMadisonUSA

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