A Local Ensemble Kalman Filter for the Ncep Gfs Model

نویسندگان

  • Istvan Szunyogh
  • Eric J. Kostelich
  • Gyorgyi Gyarmati
  • Brian R. Hunt
  • Edward Ott
  • Aleksey V. Zimin
  • Eugenia Kalnay
  • Dhanurjay Patil
  • James A. Yorke
چکیده

This paper outlines the basic concept and mathematical formulation of the Local Ensemble Kalman Filter (LEKF, Ott et al. 2002 and 2003) data assimilation scheme. Some important properties of the scheme are illustrated by numerical experiments with the Lorenz-96 model. Initial implementations of the LEKF on the National Centers for Environmental Prediction Global Forecast System (NCEP GFS) are discussed. Tests of these implementations under the perfect model hypothesis are conducted.

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تاریخ انتشار 2003