Auxiliary material for "Using generalized cross-validation to select parameters in inversions for regional carbon fluxes" Nir Y. Krakauer, Tapio Schneider (California Institute of Technology), James T. Randerson (Earth System Science, University of California, Irvine), Seth C. Olsen (California Institute of Technology) Geophysical Research Letters (accepted 12 July 2004) DOI: 10.1029/2004GL020323 Introduction This online supplement discusses in more detail and expands on some of the technical issues treated in the paper. It reviews regularization methods for the solution of linear ill-posed problems, relates different regularization methods that are used in inversions for regional carbon fluxes to the singular value decomposition of the transport operator converted to standard form, and shows how generalized cross-validation can be used to choose regularization parameters for different regularization methods. Files included 2004GL020323-supplement.tex: a LaTeX 2e file 2004GL020323-supplement.pdf