Tyler B. Coplen 2016 <p><span>Moseley </span><i>et al</i><span>.’s (Reports, 8 January 2016, p. 165) preferred-Termination-II age is subjective, as evidenced by variation in their Termination-II ages of 2500 years per meter. Termination-II-age bias decreases to zero at ~1.5 meters below the present-day water table, if one assumes linear variation with core-sample height. Maintaining the required gradient of thorium isotope </span>²³⁰<span>Th over 3.6 meters for 1000 years, much less 10,000 years, seems exceedingly unlikely.</span></p> application/pdf 10.1126/science.aaf8074 en Science Comment on “Reconciliation of the Devils Hole climate record with orbital forcing” article