Using an adjoint model to improve an optimum interpolation-based data-assimilation system

X.-Y. Huang; N. Gustafsson; E. R. Källén

doi:10.3402/tellusa.v49i2.14461

Using an adjoint model to improve an optimum interpolation-based data-assimilation system

Tellus

Volume 49 (1997): Issue 2

By: X.-Y. Huang, N. Gustafsson and E. R. Källén

Open Access

|Jan 1997

Abstract

A highly simplified 4-dimensional variational data assimilation (4DVAR) system is formulated aiming at an early operational implementation on current supercomputers. The system is a hybrid system based on both an intermittent data assimilation, including an Optimal Interpolation (OI) analysis scheme, and a 4DVAR setup. The idea is to use the adjoint model to produce an improved first-guess for the OI scheme. A 5-day data assimilation is chosen to demonstrate the applicability of our method. It is shown that the analysis increments are reduced and the forecast of a rapid cyclone development is improved.

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Articles in this issue

DOI: https://doi.org/10.3402/tellusa.v49i2.14461 | Journal eISSN: 3035-9554

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Language: English

Page range: 161 - 176

Submitted on: Jun 12, 1996

Accepted on: Sep 16, 1996

Published on: Jan 1, 1997

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 1997 X.-Y. Huang, N. Gustafsson, E. R. Källén, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 49 (1997): Issue 2