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We present new paleoclimate reconstructions for the time period of 6000yr BP (6ka) that permit a quantitative comparison to corresponding mapped patterns of the newest version of the Canadian CCCma AGCM2 climate model. July temperature reconstructions were estimated using the modern analog technique employing fossil pollen records from the North American Pollen Database. We present a new method of optimizing critical choices within the application of the MAT through modern calibration. The pattern of 6ka temperature anomalies generated by the CCCma AGCM2 generally agree with those of the pollen-based reconstruction, particularly in the presence of a band of positive temperature anomalies across the continent from the Yukon through the Great Lakes region and along the St. Lawrence. This agreement suggests that both the model and data are reconstructing a contraction in the polar vortex …