Tangent Linear and Adjoint Versions of NASA/GMAO’s Fortran 90 Global Weather Forecast Model

  • Ralf Giering
  • Thomas Kaminski
  • Ricardo Todling
  • Ronald Errico
  • Ronald Gelaro
  • Nathan Winslow
Part of the Lecture Notes in Computational Science and Engineering book series (LNCSE, volume 50)

Abstract

The NASA finite-volume General Circulation Model (fvGCM) is a three-dimensional Navier-Stokes solver being used for quasi-operational weather forecasting at NASA/GMAO. We use the automatic differentiation tool TAF to generate eficient tangent linear and adjoint versions from the Fortran 90 source code of fvGCM’s dynamical core. fvGCM’s parallelisation capabilities based on OpenMP and MPI have been transferred to the tangent linear and adjoint codes. For OpenMP, TAF automatically inserts corresponding OpenMP directives in the derivative code. For MPI, TAF generates interfaces to hand-written tangent linear and adjoint wrapper routines. TAF also generates a scheme that allows the tangent linear and adjoint models to linearise around an external trajectory of the model state. The generation procedure is set up in an automated way, allowing quick updates of the derivative codes after modifications of fvGCM.

Keywords

Singular Vector Adjoint Model Compiler Optimisation Fortran Compiler Command Line Option 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer 2006

Authors and Affiliations

  • Ralf Giering
    • 1
  • Thomas Kaminski
    • 1
  • Ricardo Todling
    • 2
  • Ronald Errico
    • 2
  • Ronald Gelaro
    • 2
  • Nathan Winslow
    • 2
  1. 1.FastOptHamburgGermany
  2. 2.Global Modeling and Assimilation OfficeNASA/GSFCMarylandUSA

Personalised recommendations