Fig. 5.

Latitudinal dependence of the model−data mismatch at different timescales. Shown is the variance ratio between observed and GCM simulated sea surface temperature, where simulations are sampled at the data positions and observational estimates are corrected for sampling and measurement errors. Proxy comparisons (dots) are relative to different versions of the ECHAM5/MPIOM model results: at timescales less than 1,000 y (A−D), comparisons are from the fully forced results, whereas comparisons at millennial timescales (E) are for the orbital-only results. Ratios derived from the orbital-only simulation are also shown as small stars in D and demonstrate that results are consistent using either model version. Variance ratios from instrumental observations (HADSST3) at the proxy positions (cyan square) are shown in A and B. Error bars show 67% confidence intervals, comparable to a SE, and include uncertainties associated with the correction process (see Materials and Methods).