Model-Dependent Spatial Skill in Pseudoproxy Experiments Testing Climate Field Reconstruction Methods for the Common Era

The increasing availability of forced-transient simulations of the last millennium (e.g., Fernández-Donado et al. 2013; Masson-Delmotte et al. 2013; Otto-Bliesner et al. 2015) from fully-coupled General Circulation Models (GCMs) has greatly improved the potential for investigating multidecadal-to-centennial-scale climate dynamics (e.g. Coats et al. 2013a, b, 2015a, b) and for comparing paleoclimate reconstructions with model output (e.g. Phipps et al. 2013; Schmidt et al. 2014; Hind et al. 2012, 2013; Coats et al. 2013a, b, 2015a, b; Anchukaitis et al. 2010; Seager et al. 2008; Fernández-Donado et al. 2013; Ault et al. 2013a, b; Lehner et al. 2012; Goosse et al. 2010, 2012; Sundberg et al. 2012; Berdahl and Robock 2013; Bothe et al. 2015). Among the currently available collection of simulations, the Coupled and Paleo Model Intercomparison Projects Phases 5 and 3 (CMIP5/PMIP3) have, for the first time, produced multiple last-millennium (LM), historical, and future simulations using the same model configurations and resolutions (Taylor et al. 2012). This development makes possible a wide range of model analyses and comparisons between paleoclimatic data and LM simulations, with direct quantitative applicability to historical simulations and future projections. One important application of the LM simulations in the CMIP5/PMIP3 database is their use in pseudoproxy Abstract The spatial skill of four climate field reconstruction (CFR) methods is investigated using pseudoproxy experiments (PPEs) based on five last millennium and historical simulations from the Coupled and Paleo Model Intercomparison Projects Phases 5 and 3 (CMIP5/ PMIP3) data archives. These simulations are used for the first time in a PPE context, the frameworks of which are constructed to test a recently assembled multiproxy network and multiple CFR techniques. The experiments confirm earlier findings demonstrating consistent methodological performance across the employed methods and spatially dependent reconstruction errors in all of the derived CFRs. Spectral biases in the reconstructed fields demonstrate that CFR methods can alone alter the ratio of spectral power at all locations in the field, independent of whether there are any spectral biases inherent in the underlying pseudoproxy series. The patterns of spectral biases are model dependent and indicate the potential for regions in the derived CFRs to be biased by changes in either low or high-frequency spectral power. CFR methods are also shown to alter the pattern of mean differences in the tropical Pacific during the Medieval Climate Anomaly and the Little Ice Age, with some model experiments indicating that CFR methodologies enhance the statistical likelihood of achieving larger mean differences between independent 300-year periods in the region. All of the characteristics