Geography Reference
In-Depth Information
CHAPTER 13
Numerical Modeling and
Prediction
Dynamical meteorology provides the theoretical basis and methodology for
modern weather forecasting. Stated simply, the objective of dynamical forecasting
is to predict the future state of the atmospheric circulation from knowledge of its
present state by use of numerical approximations to the dynamical equations. To
fulfill this objective requires observations of the initial state of the field variables,
a closed set of prediction equations relating the field variables, and a method
of integrating the equations in time to obtain the future distribution of the field
variables.
Numerical prediction is a highly specialized field, which is continually evolving.
Operational forecast centers utilize complex prediction models that require the
largest available supercomputers for their solution. It is difficult to provide more
than a superficial introduction to such models in an introductory text. Fortunately,
however, many aspects of numerical prediction can be illustrated using a simple
model, such as the barotropic vorticity equation. In fact, this equation was the basis
of the earliest operational numerical prediction models.
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