How to interpret palaeoclimate CLAMP estimates - is it a number value or an interval range?


Authors: Teodoridis V, Mazouch P

Published in: Bulletin of Geosciences, volume 91, issue 4; pages: 661 - 668; Received 15 December 2015; Accepted in revised form 9 October 2016; Online 15 November 2016

Keywords: palaeoclimate, proxy-data, estimate, CLAMP, STDEV residual, confidence interval,

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Supplementary material

Appendix 1 (487 kB)

Modern CLAMP calibration datasets

Appendix 2 (531 kB)

"Copy & Paste" application for calculation of values of limits of the Confidence Intervals for each palaeoclimate parameters and modern CLAMP calibration datasets (Appendix 1)

Appendix 3 (1725 kB)

Source datasets containing the CLAMP “result” files



Palaeoclimatic estimates derived from CLAMP are usually presented as an exact value/number. However, in order to be correct, palaeoclimatic estimates derived from the CLAMP calibration datasets including physiognomic and meteorological characteristics of living vegetation must be expressed as intervals. This study introduces a method for calculating confidence intervals of CLAMP estimates. These intervals are generated separately for each palaeoclimate parameter and dataset of modern calibration sites and will help to interpret the obtained CLAMP results in a statistically sound way.


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