A comparison of the lower stratospheric age spectra derived from a general circulation model and two data assimilation systems

2003 ◽  
Vol 108 (D3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Mark R. Schoeberl ◽  
Anne R. Douglass ◽  
Zhengxin Zhu ◽  
Steven Pawson
Keyword(s):  
Data Assimilation ◽  
General Circulation Model ◽  
General Circulation ◽  
Circulation Model

scholarly journals A Multivariate Balanced Initial Ensemble Generation Approach for an Atmospheric General Circulation Model

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 122
Author(s):  
Juan Du ◽  
Fei Zheng ◽  
He Zhang ◽  
Jiang Zhu
Keyword(s):  
Data Assimilation ◽  
General Circulation Model ◽  
General Circulation ◽  
Atmospheric General Circulation Model ◽  
Circulation Model ◽  
Atmospheric General Circulation ◽  
Ensemble Data ◽  
Initial Ensemble ◽  
Assimilation Scheme ◽  
Ensemble Generation

Based on the multivariate empirical orthogonal function (MEOF) method, a multivariate balanced initial ensemble generation method was applied to the ensemble data assimilation scheme. The initial ensembles were generated with a reasonable consideration of the physical relationships between different model variables. The spatial distribution derived from the MEOF analysis is combined with the 3-D random perturbation to generate a balanced initial perturbation field. The Local Ensemble Transform Kalman Filter (LETKF) data assimilation scheme was established for an atmospheric general circulation model. Ensemble data assimilation experiments using different initial ensemble generation methods, spatially random and MEOF-based balanced, are performed using realistic atmospheric observations. It is shown that the ensembles integrated from the balanced initial ensembles maintain a much more reasonable spread and a more reliable horizontal correlation compared with the historical model results than those from the randomly perturbed initial ensembles. The model predictions were also improved by adopting the MEOF-based balanced initial ensembles.

Sign in / Sign up

Export Citation Format

Share Document