South Pole paleowind from automated synthesis of ice core records

Abstract

We develop a fully automated reconstruction of South Pole surface roughness as a measure of past wind intensity, using dynamic warping feature recognition and internal consistency checks to reduce subjectivity and analysis time. We synchronized millimeter-resolution optical profiles of deep South Pole glacial dust together with ice core data between the ages 26 and 90 thousand years B.P. The images were captured using a laser dust logger in six boreholes of the IceCube neutrino detector array, a massive construction project in the ice at South Pole and an unusual opportunity for glaciology and paleoclimate research. South Pole surface roughness anticorrelated with curves of Antarctic pCO 2 and temperature, which we propose were connected through secular migrations of the Southern Hemisphere westerlies. This new paleoclimate signal may be direct evidence of atmospheric reorganization during the glacial, helping to deconvolve the thermodynamics and biogeochemistry of climate change. We also found that local intensity of atmospheric circulation roughly tracked the quantity of wind-borne particulates deposited in Antarctic ice during the glacial period, although the largest dust increases were likely furnished by the source regions. Copyright 2010 by the American Geophysical Union.