Spatio-Temporal Variability in Benthic δ13c Across the Last Deglaciation

Monday, 15 December 2014
Carlye D Peterson and Lorraine E Lisiecki, University of California Santa Barbara, Santa Barbara, CA, United States
Ocean circulation changes during the last glacial termination played an important role in atmospheric CO2 rise and millennial-scale climate change. These circulation changes can be reconstructed using benthic δ13C from Cibicidoides wuellerstorfi as a proxy for deep water geometry and ventilation. Here we analyze spatio-temporal variability in benthic δ13C across the deglaciation using data from ~90 core locations (70 from the Atlantic). We reconstruct patterns of δ13C change in 1-kyr timeslices from 2-24 kyr ago. Principal component analysis reveals the primary modes of deep water circulation change and their links to millennial-scale climate change. 3D visualization tools assist in the interpretation of benthic δ13C spatial patterns with respect to complex basin geometry (e.g. East vs. West Atlantic). Additionally, we present regional δ13C stacks that improve the signal-to-noise ratio for estimates of the mean δ13C change in different water masses through time.