An observation-based method for reconstructing ocean surface changes using a 340,000-year deuterium excess record from the Dome Fuji ice core, Antarctica

An extended deuterium excess (d or d-excess) record covering the last three glacial-interglacial cycles (ca. 340,000 years) was obtained from the Dome Fuji ice core, Antarctica. In order to interpret the Antarctic d record as a climatic history of vapor source regions, the record should be corrected for the Antarctic site temperature effect. We propose an observation-based method for correcting the d record. That method uses a regression curve of the observed spatial relationship between deltaD and d in Antarctica on the assumption that the present slope has not changed. Unlike the previously proposed model-based method, our correction method results in considerable change in the d profile of the Dome Fuji ice core. The corrected d record anticorrelates with a mean ocean delta(18)O record (R-2 = 0.74) and correlates with a SST record (R-2 = 0.58) throughout the observed period. These results emphasize the significance of our empirical correction method.