Devils Hole, Nevada, δ18O record extended to the mid-Holocene

The mid-to-late Pleistocene Devils Hole delta O-18 record has been extended from 60,000 to 4500 yr ago. The new delta O-18 time series, in conjunction with the one previously published, is shown to be a proxy of Pacific Ocean sea surface temperature (SST) off the coast of California. During marine oxygen isotope stages (MIS) 2 and 6, the Devil Hole and SST time series exhibit a steady warming that began 5000 to > 10,000 yr prior to the last and penultimate deglaciations. Several possible proximate causes for this early warming are evaluated. The magnitude of the peak delta O-18 or SST during the last interglacial (LIG) is significantly greater (1 per mill and 2 to 3 degrees C, respectively) than the peak value of these parameters for the Holocene; in contrast, benthic delta O-18 records of ice volume show only a few tenths per mill difference in the peak value for these interglacials. Statistical analysis provides an estimate of the large shared information (variation) between the Devils Hole and Eastern Pacific SST time series from similar to 41 to similar to 2 degrees N and enforces the concept of a common forcing among all of these records. The extended Devils Hole record adds to evidence of the importance of uplands bordering the eastern Pacific as a source of archives for reconstructing Pacific climate variability. (c) 2006 University of Washington. All rights reserved.