Variational Data Assimilation via Sparse Regularization
Document Type
Article
Journal/Book Title/Conference
Tellus
Volume
66
Publisher
The International Meteorological Institute in Stockholm
Publication Date
1-1-2013
Abstract
This paper studies the role of sparse regularisation in a properly chosen basis for variational data assimilation (VDA) problems. Specifically, it focuses on data assimilation of noisy and down-sampled observations while the state variable of interest exhibits sparsity in the real or transform domains. We show that in the presence of sparsity, the -norm regularisation produces more accurate and stable solutions than the classic VDA methods. We recast the VDA problem under the -norm regularisation into a constrained quadratic programming problem and propose an efficient gradient-based approach, suitable for large-dimensional systems. The proof of concept is examined via assimilation experiments in the wavelet and spectral domain using the linear advection–diffusion equation.
Recommended Citation
Ebtehaj, A.M., M. Zupanski, G. Lerman, E. Foufoula-Georgiou (2013), Variational Data Assimilation via Sparse Regularization, Tellus A, 2014, 66, 21789