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Channell, JET, Stoner JS, Hodell DA, Charles CD.  2000.  Geomagnetic paleointensity for the last 100 kyr from the sub-antarctic South Atlantic: a tool for inter-hemispheric correlation. Earth and Planetary Science Letters. 175:145-160.   10.1016/s0012-821x(99)00285-x   AbstractWebsite

We report relative paleointensity proxy records from four piston cores collected near the Agulhas Ridge and Meteor Rise (South Atlantic). The mean sedimentation rate of the cores varies from 24 cm/kyr to 11 cm/kyr. The two cores with mean sedimentation rates over 20 cm/kyr record positive remanence inclinations at 40-41 ka coeval with the Laschamp Event. Age models are based on oxygen isotope data from three of the cores, augmented by radiocarbon ages from nearby Core RC11-83, and by correlation of paleointensity records for the one core with no oxygen isotope data. The relative paleointensity proxy records are the first from the South Atlantic and from the high to mid-latitude southern hemisphere. Prominent paleointensity lows at similar to 40 ka and similar to 65 ka, as well as many other features, can be correlated to paleointensity records of comparable resolution from the northern hemisphere. The records are attributable, in large part, to the global-scale field, and therefore have potential for inter-hemispheric correlation at a resolution difficult to achieve with isotope data alone. (C) 2000 Elsevier Science B.V. All rights reserved.

Charles, CD, Fairbanks R.  1990.  Glacial to interglacial changes in the isotopic gradients of southern ocean surface water. The Geologic History of Polar oceans: Arctic Vs Antarctic NATO/ASI series. ( Bleil U, Thiede J, Eds.). Abstract
Charles, CD, Rind D, Jouzel J, Koster RD, Fairbanks RG.  1994.  Glacial-Interglacial Changes in Moisture Sources for Greenland - Influences on the Ice Core Record of Climate. Science. 263:508-511.   10.1126/science.263.5146.508   AbstractWebsite

Large, abrupt shifts in the O-18/O-16 ratio found in Greenland ice must reflect real features of the climate system variability. These isotopic shifts can be viewed as a result of air temperature fluctuations, but determination of the cause of the changes-the most crucial issue for future climate concerns-requires a detailed understanding of the controls on isotopes in precipitation. Results from general circulation model experiments suggest that the sources of Greenland precipitation varied with different climate states, allowing dynamic atmospheric mechanisms for influencing the ice core isotope shifts.

Lynch-Stieglitz, J, Fairbanks RG, Charles CD.  1994.  Glacial-interglacial history of Antarctic Intermediate Water: Relative strengths of Antarctic versus Indian Ocean sources. Paleoceanography. 9:7-29.   10.1029/93PA02446   AbstractWebsite

Sediment cores from the southern continental margin of Australia are near the formation region of Antarctic Intermediate Water (AAIW) and Subantarctic Mode Water and record the changes in these water masses from the last glacial maximum through the present. Carbon and oxygen isotopes were measured on the benthic foraminiferal species Planulina wuellerstrorfi for both the Recent and last glacial maximum sections of the cores and were then used to reconstruct temperature and carbon isotopic water column profiles. The glacial oxygen isotope profile indicates a vertical temperature structure for this region similar to that in today's Subantarctic Zone. Although intermediate water δ13C cannot be used as a nutrient tracer in this region because of the large influence of air-sea carbon isotopic exchange on this water mass, δ13C can be used as a water mass tracer. Today, AAIW properties reflect contributions from cool, fresh Antarctic Surface Waters (2/3) and warm, salty waters from the Indian Ocean (1/3). When examined in conjuction with the glacial δ13C and δ18C data from the north Indian and Southern Oceans, our data suggest a much reduced contribution of North Indian Ocean intermediate water to glacial Antarctic Intermediate Water relative to the contribution of Antarctic Surface Water. This fresher, cooler glacial Antarctic Intermediate Water would be distributed to the intermediate-depth ocean, thus decreasing the transport of salt produced in the North Indian Ocean to the rest of the world's oceans. Combined with evidence for a reduced influence of North Atlantic Deep Water, these results suggest major changes in the pathways for the redistribution of heat and salt in the glacial ocean.