%0 Journal Article
%T Global Speleothem Oxygen Isotope Measurements Since the Last Glacial Maximum
%A A. M. Shah
%A C. Morrill
%A E. P. Gille
%A W. S. Gross
%A D. M. Anderson
%A B. A. Bauer
%A R. Buckner
%A M. Hartman
%J Dataset Papers in Science
%D 2013
%R 10.7167/2013/548048
%X This synthesis of thirty-six sites (sixty cores with over 27£¿000 measurements) located around the world facilitates scientific research on the climate of the last 21£¿000 years ago obtained from oxygen isotope ( or delta-O-18) measurements. Oxygen isotopes in speleothem calcite record the influence of ambient temperature and the isotopic composition of the source water, the latter providing evidence of hydrologic variability and change. Compared to paleoclimate proxies from sedimentary archives, the age uncertainty is unusually small, around +/£¿100 years for the last 21£¿000-year interval. Using data contributed to the World Data Center (WDC) for Paleoclimatology, we have created consistently formatted data files for individual sites as well as composite dataset of annual to millennial resolution. These individual files also contain the chronology information about the sites. The data are useful in understanding hydrologic variability at local and regional scales, such as the Asian summer monsoon and the Intertropical Convergence Zone (as discussed in the underlying source publications), and should also be useful in understanding large-scale aspects of hydrologic change since the Last Glacial Maximum (LGM). 1. Introduction Speleothems are precipitated calcium carbonate deposits in caves. Stalagmites grow from the ground up in caves, stalactites are the formations that hang from the ceilings, and flowstones are sheetlike deposits that form on walls and floors. Oxygen isotope measurements from cave deposits provide some of the highest-resolution and best-dated information about past fluctuations in temperature and precipitation. Over the past decade, a relatively dense network of sites has been measured spanning the time period from the Last Glacial Maximum (LGM; 21£¿000 years ago) to present. These sites yield data that address key scientific questions surrounding climate sensitivity to greenhouse gas concentrations, nonlinear responses and thresholds in the climate system, and the skill of state-of-the-art climate models in reproducing states different from the present one. The ratio of two stable isotopes of oxygen, 16O and 18O, is used by paleoclimatologists as tracers of the hydrologic cycle. This is possible because the amount of one relative to the other is altered as water goes through phase changes such as evaporation and condensation. Thus, the measure (delta-O-18), which is defined as has climatological significance. The standard for carbonates such as cave deposits is the Pee Dee Belemnite (PDB), a Cretaceous marine fossil [1]. Samples with
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