Dasuopu, China Ice Core Oxygen Isotope Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Dasuopu, China Ice Core Oxygen Isotope Data LAST UPDATE: 9/2004 (Original receipt by WDC Paleo) CONTRIBUTOR: Ellen Mosley-Thompson, The Ohio State University IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2004-058 SUGGESTED DATA CITATION: Thompson, L.G., et al.. 2004. Dasuopu, China Ice Core Oxygen Isotope Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2004-058. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCES: Thompson, L.G., T. Yao, E. Mosley-Thompson, M.E. Davis, K.A. Henderson, and P.-N. Lin. 2000. A high-resolution millennial record of the South Asian Monsoon from Himalayan ice cores. Science, 289, 1916-1919. Thompson, L.G., E. Mosley-Thompson, M.E. Davis, P.-N. Lin, K. Henderson, and T.A. Mashiotta. 2003. Tropical glacier and ice core evidence of climate change on annual to millennial time scales. Climatic Change, 59, 137-155. ABSTRACT (Thompson et al. 2000): A high-resolution ice core record from Dasuopu, Tibet, reveals that this site is sensitive to fluctuations in the intensity of the South Asian Monsoon. Reductions in monsoonal intensity are recorded by dust and chloride concentrations. The deeper, older sections of the Dasuopu cores suggest many other periods of drought in this region, but none have been of greater intensity than the greatest recorded drought, during 1790 to 1796 A.D. of the last millennium. The 20th century increase in anthropogenic activity in India and Nepal, upwind from this site, is recorded by a doubling of chloride concentrations and a fourfold increase in dust. Like other ice cores from the Tibetan Plateau, Dasuopu suggests a large-scale, plateau-wide 20th-century warming trend that appears to be amplified at higher elevations. ABSTRACT (Thompson et al. 2003): This paper examines the potential of the stable isotopic ratios, 18O/16O (d18Oice) and 2H/1H (dDice), preserved in mid to low latitude glaciers as a tool for paleoclimate reconstruction. Ice cores are particularly valuable as they contain additional data, such as dust concentrations, aerosol chemistry, and accumulation rates, that can be combined with the isotopic information to assist with inferences about the regional climate conditions prevailing at the time of deposition. We use a collection of multi-proxy ice core histories to explore the d18O-climate relationship over the last 25,000 years that includes both Late Glacial Stage (LGS) and Holocene climate conditions. These results suggest that on centennial to millennial time scales atmospheric temperature is the principal control on the d18Oice of the snowfall that sustains these high mountain ice fields. Decadally averaged d18Oice records from three Andean and three Tibetan ice cores are composited to produce a low latitude d18Oice history for the last millennium. Comparison of this ice core composite with the Northern Hemisphere proxy record (1000–2000 A.D.) reconstructed by Mann et al. (1999) and measured temperatures (1856–2000) reported by Jones et al. (1999) suggests the ice cores have captured the decadal scale variability in the global temperature trends. These ice cores show a 20th century isotopic enrichment that suggests a large scale warming is underway at low latitudes. The rate of this isotopically inferred warming is amplified at higher elevations over the Tibetan Plateau while amplification in the Andes is latitude dependent with enrichment (warming) increasing equatorward. In concert with this apparent warming, in situ observations reveal that tropical glaciers are currently disappearing. A brief overview of the loss of these tropical data archives over the last 30 years is presented along with evaluation of recent changes in mean d18Oice composition. The isotopic composition of precipitation should be viewed not only as a powerful proxy indicator of climate change, but also as an additional parameter to aid our understanding of the linkages between changes in the hydrologic cycle and global climate. GEOGRAPHIC REGION: Southwest China PERIOD OF RECORD: 1997 - 1000 A.D. DESCRIPTION: Decadally averaged d18O (1990 - 1000 A.D.) from figure 5 of Thompson et al. 2003. Core location: Dasuopu glacier (28°23'N, 85°43'E, 7000 m.) Data: Decadal averages oxygen isotopic ratio Dasuopu d18O date at top of interval A.D. 1997 -17.34 1990 -18.58 1980 -17.67 1970 -17.97 1960 -17.91 1950 -17.14 1940 -18.41 1930 -19.01 1920 -19.78 1910 -18.58 1900 -20.24 1890 -18.65 1880 -18.65 1870 -20.20 1860 -18.98 1850 -19.72 1840 -19.97 1830 -19.35 1820 -20.67 1810 -19.63 1800 -18.67 1790 -21.52 1780 -21.04 1770 -21.08 1760 -19.63 1750 -19.29 1740 -21.99 1730 -19.77 1720 -20.68 1710 -19.93 1700 -19.42 1690 -19.58 1680 -19.28 1670 -20.63 1660 -20.72 1650 -19.95 1640 -20.04 1630 -20.84 1620 -21.29 1610 -20.78 1600 -21.10 1590 -20.83 1580 -20.53 1570 -20.71 1560 -20.69 1550 -19.98 1540 -20.56 1530 -20.71 1520 -21.33 1510 -20.56 1500 -19.93 1490 -20.34 1480 -20.58 1470 -20.77 1460 -20.24 1450 -21.29 1440 -20.60 1430 -21.38 1420 -20.79 1410 -21.09 1400 -20.46 1390 -19.81 1380 -20.60 1370 -20.71 1360 -20.27 1350 -20.36 1340 -20.69 1330 -21.03 1320 -20.41 1310 -21.12 1300 -20.35 1290 -20.42 1280 -21.00 1270 -20.24 1260 -20.44 1250 -21.12 1240 -19.67 1230 -20.89 1220 -21.30 1210 -20.69 1200 -21.34 1190 -20.78 1180 -21.08 1170 -20.98 1160 -20.77 1150 -20.50 1140 -20.67 1130 -21.94 1120 -21.38 1110 -20.89 1100 -21.48 1090 -21.22 1080 -21.73 1070 -20.56 1060 -20.71 1050 -21.93 1040 -21.71 1030 -21.52 1020 -21.47 1010 -22.18