Adiabatic and Diabatic Initialization of the AFGL (Air Force Geophysics Laboratory) Global Spectral Model Using Dynamic Normal Mode and Nonlinear Normal Mode Methods

Abstract

Dynamic normal mode initialization (DNI) is applied to low and high resolution versions of the AFGL global spectral mode. This scheme is tested against the operational nonlinear normal mode initialization (NMI) procedure using both adiabatic and diabatic forms of the model tendencies. The DNI-based forecasts are comparable in accuracy to the NMI-based forecasts, with small differences between the adiabatic and diabatic versions of each. DNI initial conditions were somewhat more damped in the divergence fields than were the NMI fields. This is believed to be due to the frequency response characteristics of the DNI's forward-backward time scheme, which tended to partially damp resolvable wavelengths. Keywords: Numerical weather predictions, Spectral atmospheric models, Weather forecasting, Normal modes, Global model initialization, Diabatic initialization.

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Document Details

Document Type
Technical Report
Publication Date
Feb 16, 1989
Accession Number
ADA218120

Entities

People

  • Donald Norquist
  • Larry Knowlton
  • Ross Hoffman

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Abstracts
  • Accuracy
  • Air Force
  • Amplitude
  • Atmospheric Sciences
  • Availability
  • Boundaries
  • Boundary Layer
  • Convection
  • Frequency
  • Gravity
  • Gravity Waves
  • High Resolution
  • Low Resolution
  • Physics
  • Security
  • Weather Forecasting

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  • Atmospheric Science/Meteorology
  • Optical Physics and Photonics.