Model Evaluations of the Water Isotope-Climate Relationships Used in Reconstructing Palaeotemperatures

摘要

Global measurements of the annual mean HDO and H_2~(18)O concentrations in modern precipitation show that these water isotope concentrations are linearly related to the annual mean temperature at the precipitation site in middle and high latitudes. Palaeoclimatologists have used this relationship to infer palaeotemperatures from the isotope palaeodata extractable from ice cores, deep groundwaters and other such sources. For this application to be valid, however, the relationship, which is derived from spatially distributed present day data, must also hold over time at a given location as it experiences climatic changes.