The digital filter as a weak constraint in an initialization procedure of the MM5 numerical model

Authors: Ivanov S.

Year: 2006

Issue: 01

Pages: 63-71

Abstract

The weak constraint formulation of a digital filter implemented in the initialization step of the mm5 model is considered. This approach allows us to achieve the better dynamic balance between mass and wind fields in the initial conditions of the model. The results of numerical simulations show that the digital filter enables the optimal fitting of the meteorological fields during initialization as well as reduces a growth rate of forecast errors throughout a consequent integration.

Tags: data assimilation; digital filter; model initialization

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