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Ninneman, US, Charles CD.  1999.  Origin of global millenial scale climate events: constraints from the Southern Ocean deep sea sedimentary record. Mechanisms of global climate change at millennial time scales. 112( Clark PU, Webb RS, Keigwin LD, Eds.).:99-112., Washington, D.C.: American Geophysical Union Abstract
Fairbanks, R, Charles CD, Wright JD.  1992.  Origin of the global meltwater pulses. Four decades of radiocarbon: an interdisciplinary approach. ( Long A, Kra R, Eds.).:473-500., New York, NY: Springer-Verlag Abstract
Shemesh, A, Charles CD, Fairbanks RG.  1992.  Oxygen Isotopes in Biogenic Silica - Global Changes in Ocean Temperature and Isotopic Composition. Science. 256:1434-1436.   10.1126/science.256.5062.1434   AbstractWebsite

A record of oxygen isotopes in biogenic silica from a deep-sea sediment core from the Southern Ocean reveals that marine diatoms retain their primary isotopic composition after burial. As a result, the marine diatom record can be combined with data on coexisting planktonic foraminifera to monitor past surface temperature and isotopic composition of seawater. The coupling of these two records allows the solution of two paleotemperature equations for each core interval. Data from a South Atlantic core show that the average delta-O-18 during the glacial period at this site was higher by about 1.3 per mil than average Holocene values, and that average glacial-age temperatures were not significantly different from average Holocene values.

Schrag, DP, Adkins JF, McIntyre K, Alexander JL, Hodell DA, Charles CD, McManus JF.  2002.  The oxygen isotopic composition of seawater during the Last Glacial Maximum. Quaternary Science Reviews. 21:331-342.   10.1016/s0277-3791(01)00110-x   AbstractWebsite

High-resolution oxygen and hydrogen isotope measurements were made on pore fluids from deep-sea sediments from sites in the North and South Atlantic. The data provide direct measurements of changes in the isotopic composition of bottom waters during the Last Glacial Maximum (LGM). Results from Ocean Drilling Program (ODP) Site 981 in the North Atlantic, currently bathed in North Atlantic Deep Water (NADW) reproduces previous results from the Ceara and Bermuda Rises, constraining the glacial-interglacial change in delta(18)O of the deep Atlantic to be 0.7-0.8parts per thousand. Results from Site 984, which is located north of Site 981 and at a shallower water depth, yield a similar value (0.8parts per thousand), providing insight into the properties of Glacial North Atlantic Intermediate Water (GNAIW). Sites from ODP Leg 177 in the South Atlantic span the modern boundary between northern and southern sources of deep water. Data from the northern site (1088) yield a similar result to sites in the tropical and North Atlantic (0.7parts per thousand). At the southern site (1093), located south of the polar front, the change is substantially larger (1.1parts per thousand), representing the change in delta(18)O of southern source waters since the LGM. These results confirm previous estimates that the global average change in delta(18)O of seawater is 1.0+/-0.1parts per thousand. Hydrogen isotopes measured on pore fluids from three sites are consistent with the oxygen isotopes from these locations, giving further support to these results. At all sites studied, the temperature of the deep ocean during the LGM, calculated by combining the pore fluid results with oxygen isotope data from benthic foraminifera, was within VC of the freezing point of seawater. (C) 2001 Elsevier Science Ltd. All rights reserved.