Vostok Ice Core Data for 420,000 Years: Readme file --------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program --------------------------------------------------------------------- NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!! NAME OF DATA SET: Vostok Ice Core Data for 420,000 Years LAST UPDATE: 11/2001 (Original Receipt by WDC Paleo). CONTRIBUTOR: Jean Robert Petit, LGGE-CNRS. IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2001-076 SUGGESTED DATA CITATION: Petit, J.R., et al., 2001, Vostok Ice Core Data for 420,000 Years, IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series #2001-076. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Petit J.R., Jouzel J., Raynaud D., Barkov N.I., Barnola J.M., Basile I., Bender M., Chappellaz J., Davis J., Delaygue G., Delmotte M., Kotlyakov V.M., Legrand M., Lipenkov V., Lorius C., Pépin L., Ritz C., Saltzman E., Stievenard M., 1999, Climate and Atmospheric History of the Past 420,000 years from the Vostok Ice Core, Antarctica, Nature, 399, pp.429-436. ADDITIONAL REFERENCES: Barnola, J.M., Raynaud, D., Korotkevich, Y.S. & Lorius, C., 1987. Vostok ice core provides 160,000-year record of atmospheric CO2. Nature, 329, 408-414. Barnola, J.M., Pimienta, P., Raynaud, D. & Korotkevich, Y.S., 1991. CO2 climate relationship as deduced from the Vostok ice core: a re-examination based on new measurements and on a re-evaluation of the air dating. Tellus, 43B, 83-91. Chappellaz, J., Barnola, J.-M., Raynaud, D., Korotkevich, Y.S. & Lorius, C. 1990. Ice-core record of atmospheric methane over the past 160,000 years. Nature, 345, 127-131. Jouzel J., C. Lorius, J. R. Petit, C. Genthon, N. I. Barkov, V. M. Kotlyakov, and V. M. Petrov, 1987, Vostok ice core: a continuous isotope temperature record over the last climatic cycle (160,000 years), Nature, 329, 1987, 402-408. Jouzel J., N. I. Barkov, J. M. Barnola, M. Bender, J. Chappelaz, C. Genthon, V. M. Kotlyakov, V. Lipenkov, C. Lorius, J. R. Petit, D. Raynaud, G. Raisbeck, C. Ritz, T. Sowers, M. Stievenard, F. Yiou and P. Yiou, 1993, Extending the Vostok ice-core record of paleoclimate to the penultimate glacial period, Nature, 364, 1993, 407-412. Jouzel J., C. Waelbroeck, B. Malaizé, M. Bender, J. R. Petit, N. I. Barkov, J. M. Barnola, T. King, V. M. Kotlyakov, V. Lipenkov, C. Lorius, D. Raynaud, C. Ritz and T. Sowers, 1996,Climatic interpretation of the recently extended Vostok ice records, Clim.Dyn., 12, 513-521. Legrand M., C. Lorius, N;I. Barkov, V.N. Petrov, 1988, Vostok (Antarctica) ice core: atmospheric chemistry changes over the last climatic cycle (160,000 years), Atmos. Environ. 1988, 22, 317-331. Lorius C., J. Jouzel, C. Ritz, L. Merlivat, N. I. Barkov, Y. S. Korotkevitch, and V. M. Kotlyakov, 1985, A 150,000-year climatic record from Antarctic ice, Nature, 316, 591-596. Petit J.R., L. Mounier, J. Jouzel, Y. Korotkevitch, V. Kotlyakov and C. Lorius, 1990, Paleoclimatological implications of the Vostok core dust record, Nature, 343, 56-58. Sowers T. M. Bender, L. D. Labeyrie, J. Jouzel, D. Raynaud, D. Martinson, and Y. S. Korotkevich, 1993, 135,000 year Vostok - SPECMAP common temporal framework, Paleoceanography v.8, p. 737-766. GEOGRAPHIC REGION: Antarctica PERIOD OF RECORD: 0-422 KYrBP LIST OF FILES: Readme_petit1999.txt (this file), GT4nat.txt, deutnat.txt, dustnat.txt, nanat.txt, ch4nat.txt, co2nat.txt, o18nat.txt (Tab-delimited ASCII format). DESCRIPTION: Vostok Ice Core Data for 420,000 Years Files content: "GT4" ice core chronology (gas and ice chronology), Deuterium and reconstructed temperature, Dust content, Sodium concentrations, CO2, CH4, atmospheric oxygen composition. Vostok time scales : file "GT4nat.txt" Column 1: depth (m) Column 2: Age of the ice (GT4 chronology) Column 3: Gas Age as deduced from the Barnola et al. (1991) model. Deuterium - data : file « deutnat.txt » Column 1 -Depth (m) Column 2 -Ice Age (GT4) Column 3 –Deuterium content in ‰ SMOW (Standard Mean Ocean Sea Water). Deuterium measurements have been performed on three adjacent cores 3G, 4G and 5G (see Figure 1 of Jouzel et al., 1996). It combines results successively published in Jouzel et al. (1987, 1993 and 1996). Column 4 -Temperature difference wrt the mean recent time value (i.e. corresponding departure from –438 ‰ mean deuterium value) Deuterium data is from core 3G between 138 and 2083 meters below surface (mbs) (with one long missing section between 312 and 320 mbs), from core 4G between 8 and 138 mbs and between 1920 and 2546 mbs and from core 5G between 2504 and 2757 mbs. Ash layers help to make link between cores. No correction was applied for 3G and 4G core taken as reference depth. For 5G samples, a value of 3.41 m have been added to the depth measured in the field below depth of 2500 m. Deuterium values (column 3) have been measured on ice samples of length comprised between 0.5 and 2 m (down to 2080 m) then every 1 m. Data was re-interpolated on 1m intervals afterwards. The ice recovery is 85% or higher. Measurement accuracy is of ± 0.5‰ SMOW (1 s). From the surface down to 7 m a constant value (derived from surface and pits samples) of -438.0 ‰ is reported. The temperature change indicated in column 4 (temperature above the inversion). This temperature is calculated using a deuterium/temperature gradient of 9‰/°C after accounting for the isotopic change of sea-water. No correction for the influence of the geographical position of the ice was applied. Dust content: file "dustnat.txt" Column 1 -Ice Age (GT4) Column 2 – dust concentration in ppm The dust concentration was calculated from the total volume concentration (from Coulter counter measurements), and assuming a dust density of 2.500 Kg. m-3. Data from Petit et al (1990), Jouzel et al. (1993) down to 2545 m depth have been included. Sodium content file "nanat.txt" Column 1: Ice age (GT4 chronology) Column 2: Sodium concentration (ppb) Data from Legrand et al.(1988) ,down to 2080 m have been included. CH4 data: file"ch4nat.txt" Column 1: Gas Age as deduced from the Barnola et al. (1991) model Column 2: CH4 concentration (ppbv). See note below CO2 data: file"co2nat.txt" Column 1: Gas Age as deduced from the Barnola et al. (1991) model Column 2: CO2 concentration (ppmv). CO2 and CH4 measurements have been performed using the methods and analytical procedures previously described (Barnola et al., 1987, Chappellaz et al, 1990). However, the CO2 measuring system has been slightly modified in order to increase the sensitivity of the CO2 detection. The thermal conductivity chromatographic detector has been replaced by a flame ionisation detector which measures CO2 after its transformation into CH4. The overall accuracy for CH4 and CO2 measurements are ± 20 ppbv and 2-3 ppmv respectively. No gravitational correction has been applied. Atmospheric Oxygen : file "o18nat.txt" Column 1: Gas Age as deduced from the Barnola et al. (1991) model Column2: d18Oatm ‰ d18Oatm data published in Sowers et al.(1993) and Jouzel et al.(1993) have been included. Gas age CO2 (ppmv) 2342 284.7 3634 272.8 3833 268.1 6220 262.2 7327 254.6 8113 259.6 10123 261.6 11013 263.7 11326 244.8 11719 238.3 13405 236.2 13989 225.3 17695 182.2 19988 189.2 22977 191.6 26303 188.5 27062 191.7 31447 205.4 33884 209.1 39880 209.1 44766 189.3 47024 188.4 48229 210.1 49414 215.7 51174 190.4 57068 221.8 57799 210.4 63687 195.4 65701 191.4 66883 195 72849 227.4 75360 229.2 78995 217.1 80059 221.8 82858 231 84929 241.1 85727 236.4 86323 228.1 87180 214.2 88051 217 89363 208 91691 224.3 92460 228.4 95349 232.1 99842 225.9 100833 230.9 101829 236.9 103372 228.2 105213 236.9 106203 230.7 108308 238.2 108994 245.7 110253 251.3 111456 256.8 112577 266.3 113472 261.4 114082 274.6 114738 273.3 116175 262.5 117519 267.6 118396 273.8 119273 272 120002 265.2 120652 277.7 121961 272.2 122606 276.5 123815 268.7 123858 266.6 124306 266.3 124571 279.8 124876 277.2 125746 273.8 126023 267.1 126475 262.5 126809 262.6 127445 275.4 128300 274.1 128399 287.1 128652 286.8 129007 282.7 129411 264.1 129755 263.4 130167 259 131789 240.4 133334 224 134205 208.9 135003 204.6 135683 198.1 135976 201.8 136359 202.5 136659 195.9 137383 194.4 137694 193.4 138226 190.2 139445 192.3 141312 196.5 142357 190.4 145435 197 150303 191.9 154471 189 155299 185.5 160494 204.4 162996 191.6 165278 183.8 169870 197.9 172596 197.8 175440 190.3 176271 190.1 178550 207.7 180779 213.2 181617 217.7 183355 199.8 185063 203.5 187199 210.7 189335 231.4 191057 231.5 192632 218 195625 220.1 199025 242.6 202212 251 203191 239.1 204283 247.7 205148 244.4 205715 232.2 206119 228.7 207991 238.2 209414 242.2 210022 244.6 210830 247.3 211005 252 212281 257.4 214153 251.2 215041 241.4 215593 240.3 215879 242.7 216459 247.5 217009 251.7 217271 251.2 217676 245.4 218342 240.5 219680 212.2 220182 216.2 220760 207.2 221054 208.9 221612 205.7 222958 203.4 223446 215.7 224630 236.9 225299 234.5 225509 233.1 225888 224.5 226710 232.4 227384 233.9 227840 241.7 230703 245.2 231382 252.2 231990 241.4 232570 247.4 233102 243.1 233646 239.2 234126 245.7 234470 245.9 234781 247.4 235213 252.9 236236 259.8 237831 279 238935 263.8 239250 252.4 239545 249.9 240201 230.4 240577 219.4 242068 214.7 243653 200.2 244215 213.9 244863 195.4 245483 196.7 247447 199 248087 201.9 248980 204 250461 203.9 251521 209.7 252959 208.9 253880 214.7 255233 228.2 256053 199.9 256501 211.7 257247 188.7 258477 194.2 259228 198.9 259958 184.7 260754 190.4 261595 193.9 262411 194.2 263207 198.4 264046 193.2 264834 202.2 266492 211 267434 215.4 268679 223.7 270680 231.4 273012 226.4 274445 230.4 275218 231 277925 220.4 278602 217.2 279543 207.7 282301 212.7 283492 213.2 286217 224.4 287846 236.2 290571 240.2 291769 240.7 292474 250.2 293676 244.9 294615 225.9 295849 227.9 297131 233.2 298051 237.9 299020 239 299877 241.9 300646 251.7 301496 256.8 302456 257.2 303334 246.9 303953 272.7 304590 251.7 305306 244.7 307131 255.9 308101 249.2 310039 256.3 310930 260.4 311774 260.3 313493 266.3 315143 266.2 315940 270.2 316681 271.9 317445 275.2 318980 265 319754 271.8 320378 272.7 321386 273.2 322111 282.4 322582 289.2 322827 288.4 323485 298.7 324189 278.2 324991 285.8 325527 278.7 326239 270.5 327114 255.7 328097 241.9 329267 239.7 330208 234.2 332293 250.2 333627 200.7 335290 205.2 336972 204.9 340165 220.4 342998 221.2 344735 216.2 347610 209.2 350765 193 352412 186.2 356838 201.2 359688 206.4 362766 201.9 366221 214.7 369563 229.7 373014 227 374561 240 378194 246.9 379633 245.9 384909 264.7 386579 259.3 390589 255.2 392451 250.2 394628 266.3 396713 274.7 400390 278 405844 279.7 409022 283.7 410831 276.3 414085 285.5