Title :
The Multi-Solution Problem in 4DVar and Solved in a Smooth Subspace
Author :
Shao Ai-Mei ; Qiu Xiao-bin ; Qiu Chong-Jian
Author_Institution :
Key Lab. for Semi-Arid Climate Change of the Minist. of Educ., Lanzhou Univ., Lanzhou, China
Abstract :
The solution of 4DVar may not be unique if observation information is not enough. In order to get the expected solution we can introduce a smooth operator to carry out transformation on the control variable. The numerical experiments with shallow-water-equation model and model data show that through the transformation the analysis increment is restricted in a smooth subspace and the analysis field is more close to the truth. The study explained the significance of background error covariance matrix in 4DVar from another side.
Keywords :
covariance matrices; data assimilation; geophysical fluid dynamics; shallow water equations; 4DVar; background error covariance matrix; multisolution problem; shallow-water-equation model; smooth operator; smooth subspace; Analytical models; Cost function; Covariance matrix; Data assimilation; Data models; Numerical models; System-on-a-chip;
Conference_Titel :
Multimedia Technology (ICMT), 2010 International Conference on
Conference_Location :
Ningbo
Print_ISBN :
978-1-4244-7871-2
DOI :
10.1109/ICMULT.2010.5631091
