Possible errors of the Mutual Climatic Range (MCR) method in reconstructing the Pleistocene climate of Beringia

摘要

The main causes and degree of inaccuracy of air temperature reconstruction by the MCR method are discussed. This inaccuracy appears to result from several reasons: insufficient knowledge of geographic ranges of species, the use of calibration equations calculated for a different region, and the absence of generally accepted criteria for the selection of species to be used in MCR analysis, in relation to their distribution and ecological specificity. The maximum deviation of the reconstructed July temperature from the actual one was 2-4pC, which was 2-3 times the accepted MCR standard error. The requirements for selection of fossil species in order to improve the reconstruction accuracy are discussed.