Relation between hydrogen isotopic ratios of bone collagen and rain

Abstract

The hydrogen isotopic value (δD) of deer bone collagen is related to both δD of rain during the growing season and growing season relative humidity (RH). With correction for the effects of RH, bone δD is related to growing season rain δD in a simple manner with a slope of 1.0. This indicates that, with RH correction, there are no additional sources of bias in the δD of bone due to unaccounted for biologic or climatic effects. Due to a low sensitivity of bone δD to RH effects, both yearly and growing season rain δD can be estimated with considerable accuracy ( R = 0.97 and R = 0.96) from bone collagen δD and δ 15N. Here, δ 15N is used to correct bone δD for the effects of RH. From these estimates of rain δD, it may then be possible to evaluate temperature since the δD of rain primarily reflects local temperature. Therefore, the measurement of bone collagen δD has good potential for evaluating paleoclimates.