Antarctic & Greenland-GRIP Synchronization Data: Readme file ----------------------------------------------------------------------- World Data Center A- Paleoclimatology ----------------------------------------------------------------------- NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!! NAME OF DATA SET: Antarctic & Greenland-GRIP Synchronization Data CONTRIBUTORS: Thomas Blunier and Bernhard Stauffer, University Bern, and Jerome Chappellaz, CNRS. IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 1998-034 SUGGESTED DATA CITATION: Blunier T., Chappellaz, J., and B. Stauffer, 1998, Antarctic & Greenland(GRIP) Synchronization Data. IGBP PAGES/World Data Center-A for Paleoclimatology Data Contribution Series #1998-034. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCES: For the synchronization of Antarctic isotopes to the Grip isotopic record: ========================================================================== Blunier, T., J. Chappellaz, J. Schwander, A. Dällenbach, B. Stauffer, T. Stocker, D. Raynaud, J. Jouzel, H.B. Clausen, C.U. Hammer, and S.J. Johnsen, 1998, Asynchrony of Antarctic and Greenland climate change during the last glacial period, Nature, 394, 739-743, 20 August 1998. For the synchronization of Antarctic CO2 to the Grip isotopic record: ===================================================================== Stauffer, B., T. Blunier, A. Dällenbach, A. Indermühle, J. Schwander, T.F. Stocker, J. Tschumi, J. Chappellaz, D. Raynaud, C.U. Hammer, and H.B. Clausen, 1998, Atmospheric CO2 concentration and millennial-scale climate change during the last glacial period, Nature, 392, 59-62, 1998. GRIP isotopic record: ===================== Dansgaard, W., S.J. Johnsen, H.B. Clausen, D. Dahl-Jensen, N.S. Gundestrup, C.U. Hammer, C.S. Hvidberg, J.P. Steffensen, A.E. Sveinbjörnsdottir, J. Jouzel, and G. Bond, 1993, Evidence for general instability of past climate from a 250-kyr ice-core record, Nature, 364, 218-220, 1993. Johnsen, S.J., and W. Dansgaard, On flow model dating of stable isotope records from Greenland ice cores, in The Last Deglaciation: Absolute and Radiocarbon Chronologies. NATO ASI series, edited by E. Bard, and W.S. Broecker, pp. 13-24, Springer Verlag, 1992. Johnsen, S., D. Dahl-Jensen, W. Dansgaard, and N. Gundestrup, Greenland palaeotemperatures derived from GRIP bore hole temperature and ice core isotope profiles, 1995, Tellus, 47B, 624-629, 1995. Vostok isotopic record: ======================= Jouzel, J., C. Lorius, J.R. Petit, C. Genthon, N.I. Barkov, V.M. Kotlyakov, and V.M. Petrov, Vostok ice core: A continuous isotope temperature record over the last climatic cycle (160,000 years), Nature, 329, 403-408, 1987. Byrd isotopic record: ===================== Johnsen, S.J., W. Dansgaard, H.B. Clausen, and C.C. Langway, Jr, Oxygen isotope profiles through the Antarctic and Greenland ice sheets, Nature, 235 (5339), 429-434, 1972. Byrd CO2 record: ================ Neftel, A., H. Oeschger, T. Staffelbach, and B. Stauffer, CO2 record in the Byrd ice core 50000-5000 years BP, Nature, 331, 609-611, 1988. Staffelbach, T., B. Stauffer, A. Sigg, and H. Oeschger, CO2 measurements from polar ice cores: more data from different sites, Tellus, 43B, 91-96, 1991. CH4 data: ========= Blunier, T., J. Chappellaz, J. Schwander, B. Stauffer, and D. Raynaud, Variations in atmospheric methane concentration during the Holocene epoch, Nature, 374, 46-49, 1995. Chappellaz, J., J.-M. Barnola, D. Raynaud, Y.S. Korotkevich, and C. Lorius, Ice-core record of atmospheric methane over the past 160000 years, Nature, 345, 127-131, 1990. Chappellaz, J., T. Blunier, D. Raynaud, J.M. Barnola, J. Schwander, and B. Stauffer, Synchronous changes in atmospheric CH4 and Greenland climate between 40 and 8 kyr BP, Nature, 366, 443- 445, 1993. LAST UPDATE: 9/98 (Original Receipt by WDCA Paleo) GEOGRAPHIC REGION: Global PERIOD OF RECORD: 10 -50 KYrBP LIST OF FILES: Readme.Blunier1998.txt(this file), iso_bl98.txt, ch4_bl98.txt. DESCRIPTION: Data from the synchronization of Antarctic records to the Greenland GRIP record: ******************************************************************************** The data was used for Figures 2 of Stauffer et al., 1998 and Blunier et al., 1998. These references should only be used referring to the synchronised Antarctic time scale but not to the original data. References to the original data are also given above. Filename: iso_bl98.txt GRIP Byrd and Vostok isotopic data as well as Byrd CO2 data on the synchronised time scale discussed in Stauffer et al., 1997 and Blunier et al., 1998. The file contains thirteen columns: Column 1: GRIP depth (meters below the surface) Column 2: GRIP age (calendar years before 1989) Column 3: GRIP d18O (‰) Column 4: Byrd depth (meters below the surface) Column 5: Byrd age (calendar years before 1989) Column 6: Byrd d18O (‰) Column 7: Vostok depth (meters below the surface) Column 8: Vostok age (calendar years before 1989) Column 9: Vostok dD (‰) Column 10: Byrd depth (meters below the surface) Column 11: Byrd mean age of the trapped air (calendar years Before 1989) Column 12: Byrd CO2 concentration (ppmv, parts per million by volume) Column 13: Byrd CO2 one sigma (ppmv) Filename: ch4_bl98.txt GRIP Byrd and Vostok CH4 data used for the synchronization on the synchronised time scale discussed in Stauffer et al., 1997 and Blunier et al., 1998. The file contains thirteen columns: Column 1: GRIP depth (meters below the surface) Column 2: GRIP mean age of the trapped air (calendar years Before 1989) Column 3: GRIP CH4 concentration (ppbv, parts per billion by volume) Column 4: Byrd depth (meters below the surface) Column 5: Byrd mean age of the trapped air (calendar years Before 1989) Column 6: Byrd CH4 concentration (ppbv, parts per billion by volume) Column 7: Vostok depth (meters below the surface) Column 8: Vostok mean age of the trapped air (calendar years Before 1989) Column 9: Vostok CH4 concentration (ppbv, parts per billion by volume) GRIP (Greenland IceCore Project) ================================ The GRIP time scale is the reference time scale. It's construction is described in Johnsen et al., 1992 and Johnsen et al., 1995 which should also be referenced in that respect. 0 yr BP corresponds to 1989. Antarctic synchronised time scales: =================================== The Antarctic records are synchronised to the GRIP record via the fast variations of the global methane signal. The uncertainty of this synchronization is time dependent (see Blunier et al., 1998 and Stauffer et al., 1998 for details). The Byrd time scale for the isotope and for the CO2 record differ. This is so since gas is occluded not at the surface of the ice sheet but in a depth of 50-100 m depending on the site characteristics. This makes a gas sample from a specific depth younger than the surrounding ice. The time period 25-17 kyr BP was excluded from the synchronization, since only low CH4 variations appear during that period making the correlation uncertain. Note: The CO2 time scale given here is not identical to the one published in Stauffer et al., 1998. The difference is in the order of 200yr and arises due to 1) the exclusion of the time period 25-17 kyr BP which was used in Stauffer et al. 1998, and 2) a stronger smoothing of the age scale derived from the CH4 synchronization. Warnings: ========= None of the used time scale is considered as absolute. Thus fluctuations in the annual layer thickness show up in the synchronised Antarctic cores. This variations must not be taken as real. However the synchronization is not dependent on absolute time scale. The reliability of the synchronization is higher on the Byrd side since Vostok has an ice age gas age difference 10 fold larger than the Byrd one. CO2 values ========== CO2 values are mean values over 50cm depth intervals. The uncertainties are given as one sigma values for the mean values. CH4 values ========== CH4 values are mean values where multiple measurements on the same depth levels have been made. The uncertainty (one sigma) is about 10 ppbv. The original datasets from GRIP and Vostok (Blunier et al., 1997, Chappellaz et al., 1995, Chappellaz et al., (1990)) have been detailed significantly for this study. The Byrd record was first published in Blunier et al., 1998. References to the complete dataset should be made to Blunier et al.,1998. GRIP BYRD Vostok Depth Age yr BP mean concentration Depth Age yr BP mean concentration Depth Age yr BP mean concentration m (yr BP) ppm (m) (yr BP) ppbv (m) (yr BP) ppbv 1529.57 10016 720 974.20 10112 660 303.80 10838 667 1535.08 10082 719 989.50 10345 680 321.20 11711 621 1540.90 10154 727 999.08 10487 675 325.00 11891 511 1546.08 10218 714 999.60 10494 682 331.70 12215 477 1551.57 10288 720 1005.70 10579 670 342.10 12804 501 1557.08 10355 721 1024.70 10874 683 356.00 13730 662 1562.57 10425 744 1039.70 11122 677 365.60 14349 610 1573.57 10565 722 1050.90 11301 681 366.20 14387 642 1579.08 10639 715 1069.40 11592 620 381.70 15291 445 1584.57 10715 720 1079.60 11750 463 426.30 18443 395 1595.57 10870 691 1090.50 11922 464 443.50 20025 363 1601.08 10946 689 1097.90 12031 472 458.30 21368 349 1606.57 11025 719 1111.05 12286 425 471.00 22495 379 1612.10 11104 711 1117.90 12468 457 491.30 24255 348 1617.57 11182 698 1130.70 12789 672 506.40 25605 406 1621.43 11239 716 1136.37 12936 629 507.39 25688 339 1625.82 11302 677 1140.48 13046 587 510.20 25930 371 1628.61 11340 737 1150.10 13315 658 513.61 26206 377 1635.33 11424 726 1151.11 13342 685 517.62 26534 403 1640.07 11482 734 1160.33 13590 660 519.67 26686 403 1645.23 11568 686 1175.37 13999 630 522.48 26898 340 1651.08 11724 475 1181.27 14156 612 522.63 26908 360 1656.07 11860 484 1187.57 14325 613 522.73 26916 381 1662.14 12056 494 1192.00 14446 610 525.58 27131 358 1667.07 12219 472 1195.74 14544 545 528.16 27327 392 1672.60 12434 477 1199.27 14635 458 532.16 27628 377 1678.07 12647 533 1200.20 14659 463 532.36 27643 381 1683.58 12767 680 1201.10 14683 467 532.36 27643 379 1689.07 12905 666 1205.66 14797 488 535.02 27832 360 1695.15 13076 620 1216.25 15071 457 540.03 28202 363 1700.07 13188 689 1231.79 15487 445 541.45 28310 382 1705.56 13292 666 1239.62 15691 443 541.45 28310 386 1711.21 13400 685 1247.77 15894 438 545.19 28605 387 1722.07 13607 673 1252.03 16004 435 547.03 28748 412 1728.12 13732 679 1254.05 16058 415 549.37 28941 426 1733.07 13859 660 1260.82 16247 434 552.03 29163 418 1738.55 13980 583 1265.91 16431 410 554.22 29342 448 1744.07 14081 656 1284.48 17126 375 556.49 29527 464 1749.55 14164 622 1287.80 17243 380 560.19 29830 435 1755.78 14246 633 1292.84 17435 375 562.47 30019 416 1766.34 14370 653 1298.19 17657 366 563.14 30078 403 1771.55 14445 627 1302.87 17852 372 565.20 30255 382 1777.07 14577 536 1307.16 18025 369 569.19 30585 396 1782.59 14723 500 1314.11 18299 387 571.35 30778 425 1788.07 14866 464 1319.62 18517 358 574.32 31063 435 1793.55 15017 484 1320.14 18538 367 577.75 31387 436 1799.07 15197 453 1325.30 18733 357 581.82 31749 421 1804.55 15384 462 1328.87 18869 369 582.78 31834 416 1810.07 15584 482 1335.97 19124 363 583.28 31877 429 1816.61 15775 477 1339.14 19241 349 589.18 32395 481 1821.07 15909 429 1347.06 19561 348 591.65 32616 489 1827.10 16118 414 1348.39 19615 386 593.78 32803 482 1832.23 16306 416 1350.85 19715 378 599.11 33265 394 1837.55 16514 379 1356.88 19949 350 602.58 33552 429 1843.07 16693 364 1359.09 20035 373 609.68 34152 469 1848.55 16841 346 1365.50 20290 343 612.02 34359 505 1854.57 17021 374 1370.61 20496 372 615.48 34669 548 1859.94 17175 372 1380.82 20917 351 617.70 34861 532 1865.07 17322 375 1387.84 21213 345 619.53 35018 520 1871.04 17507 368 1396.22 21565 347 622.15 35238 530 1876.07 17652 359 1399.93 21720 346 625.07 35473 509 1883.16 17849 372 1408.23 22060 367 627.56 35668 483 1887.23 17961 360 1414.44 22316 381 627.56 35668 500 1893.06 18160 340 1422.54 22655 385 629.18 35792 484 1898.07 18338 372 1425.89 22781 364 633.36 36102 418 1904.06 18556 364 1436.17 23167 376 635.07 36229 403 1909.07 18756 357 1438.69 23273 365 639.47 36560 459 1915.61 18981 371 1440.93 23366 372 641.26 36700 414 1920.08 19158 374 1452.05 23807 351 644.55 36965 375 1925.29 19392 349 1455.87 23957 346 648.00 37265 423 1931.07 19683 362 1461.86 24194 355 649.23 37381 443 1937.48 20013 353 1466.96 24392 363 653.84 37845 431 1942.07 20236 347 1481.48 24974 361 664.10 38909 484 1948.06 20540 352 1484.47 25106 369 682.00 40873 520 1953.62 20814 365 1485.20 25137 369 683.00 40987 493 1958.62 21030 412 1485.96 25170 349 694.60 42248 424 1964.07 21233 402 1488.87 25294 386 699.50 42740 448 1969.71 21449 411 1491.79 25407 381 706.10 43344 537 1975.07 21694 402 1496.35 25587 437 712.90 43871 522 1982.16 22313 374 1498.92 25691 389 724.80 44663 441 1986.23 22556 375 1501.10 25777 372 748.30 46187 419 1992.61 22913 373 1502.19 25821 367 1997.07 23141 372 1503.48 25874 356 2003.04 23520 357 1507.97 26045 360 2008.07 23894 378 1511.38 26166 379 2014.06 24228 354 1512.30 26201 374 2018.68 24539 351 1514.81 26298 383 2025.06 24973 352 1515.65 26333 396 2030.07 25277 352 1517.78 26420 414 2036.08 25456 431 1520.99 26583 467 2041.62 25709 447 1521.58 26614 461 2047.09 26121 420 1523.45 26712 478 2050.97 26339 400 1523.98 26740 466 2052.19 26378 423 1527.92 26933 382 2054.27 26432 468 1532.15 27130 373 2056.42 26484 491 1533.51 27192 360 2057.02 26499 475 1534.54 27240 371 2058.53 26540 482 1536.39 27326 385 2059.18 26559 525 1539.88 27492 380 2061.97 26677 471 1545.88 27782 374 2063.58 26768 396 1557.94 28348 363 2064.72 26832 395 1563.98 28635 380 2066.87 26962 407 1568.28 28825 368 2068.02 27051 401 1573.01 29038 364 2068.55 27091 431 1578.99 29321 398 2070.72 27244 388 1582.74 29508 404 2073.47 27484 400 1584.99 29621 429 2074.03 27538 381 1588.81 29807 451 2074.60 27586 399 1591.33 29927 492 2076.77 27754 415 1594.35 30071 504 2077.90 27847 418 1597.12 30202 389 2081.17 28074 407 1599.45 30308 408 2082.30 28143 401 1603.95 30512 387 2084.48 28273 438 1609.93 30797 404 2085.62 28354 426 1611.40 30869 455 2087.25 28490 423 1614.15 31003 466 2089.42 28667 397 1620.11 31282 374 2090.57 28770 382 1624.42 31476 412 2091.65 28869 425 1629.21 31691 396 2093.79 29086 406 1632.19 31825 417 2095.52 29267 404 1636.45 32026 417 2096.05 29314 406 1638.96 32145 448 2099.32 29531 449 1648.51 32616 498 2102.06 29661 465 1651.48 32771 505 2103.20 29702 483 1652.43 32821 494 2104.33 29740 583 1656.58 33023 399 2105.95 29790 573 1665.78 33437 415 2107.07 29828 504 1670.06 33638 443 2108.73 29883 500 1676.05 33908 408 2110.35 29948 509 1682.05 34194 434 2114.78 30258 402 1686.74 34425 520 2116.95 30497 389 1691.11 34641 506 2118.07 30608 392 1696.40 34907 548 2119.22 30700 408 1698.86 35030 545 2120.25 30776 462 1714.13 35763 559 2121.93 30874 455 1716.09 35852 515 2123.55 30942 480 1717.19 35903 433 2124.52 30980 488 1718.14 35947 418 2125.23 31006 491 1719.73 36022 438 2126.85 31064 533 1723.21 36183 433 2128.53 31129 508 1724.68 36251 433 2129.07 31149 498 1725.61 36294 425 2129.60 31169 493 1726.33 36328 419 2131.34 31276 512 1726.93 36356 415 2134.00 31480 409 1727.71 36392 422 2135.10 31562 386 1728.50 36428 423 2137.33 31756 408 1730.69 36529 418 2139.50 31948 423 1731.65 36574 422 2140.07 32000 431 1733.17 36645 422 2141.80 32127 439 1735.14 36731 415 2143.90 32245 482 1735.78 36759 408 2145.55 32339 513 1736.69 36799 420 2146.68 32400 554 1737.61 36840 411 2148.30 32465 519 1738.93 36898 434 2149.98 32523 521 1739.70 36931 422 2151.32 32571 535 1740.88 36982 413 2153.73 32650 558 1742.12 37035 422 2154.35 32667 587 1743.16 37082 453 2155.48 32705 523 1745.25 37175 389 2157.45 32768 538 1746.78 37244 395 2158.20 32793 609 1747.68 37283 382 2159.88 32860 540 1748.64 37329 399 2160.95 32921 576 1749.69 37379 407 2162.10 33008 473 1751.66 37470 387 2162.63 33053 454 1752.72 37520 388 2164.80 33257 410 1753.61 37563 407 2166.49 33445 417 1754.92 37626 378 2167.55 33536 410 1759.42 37843 434 2168.10 33587 429 1763.66 38046 399 2170.33 33814 440 1765.38 38126 401 2171.95 33943 439 1769.73 38334 397 2173.05 34012 453 1772.77 38484 433 2174.18 34071 462 1774.54 38573 472 2175.80 34161 518 1777.65 38788 480 2178.03 34305 500 1780.57 39024 418 2179.07 34370 536 1787.87 39603 374 2180.20 34439 514 1789.37 39723 394 2182.49 34557 606 1795.22 40221 441 2184.07 34637 566 1797.22 40384 442 2184.60 34661 578 1798.25 40467 471 2186.28 34741 559 1801.36 40720 488 2188.45 34849 572 1804.25 40952 482 2189.92 34914 559 1810.20 41417 394 2190.68 34950 567 1813.46 41664 413 2192.85 35050 551 1819.98 42198 430 2195.62 35181 554 1822.46 42414 422 2197.87 35277 555 1826.75 42698 451 2200.00 35352 543 1828.46 42788 416 2201.52 35409 570 1831.64 42966 470 2202.78 35451 539 1835.78 43215 466 2203.85 35486 583 1837.56 43322 442 2205.53 35536 537 1841.83 43576 483 2206.62 35566 575 1843.56 43682 468 2207.70 35598 575 1847.84 43949 511 2208.83 35633 552 1850.75 44124 509 2210.45 35691 571 1855.56 44412 510 2211.55 35740 533 1858.06 44557 506 2212.68 35810 475 1861.60 44753 512 2214.30 35921 450 1864.53 44910 437 2214.85 35965 475 1867.54 45072 420 2217.24 36194 450 1870.81 45254 420 2222.55 36743 431 1873.83 45419 417 2227.52 37277 422 1880.78 45796 435 2239.07 38251 425 1884.06 45974 414 2244.55 38622 519 1891.80 46411 415 2250.07 38869 505 2255.55 39282 383 2260.62 39830 412 2266.97 40271 467 2272.17 40520 509 2278.07 40772 487 2283.07 41341 398 2288.55 41902 411 2295.72 42403 454 2299.55 42684 459 2305.07 43046 488 2311.67 43434 507 2316.07 43676 515 2321.55 43958 514 2326.52 44174 536 2332.55 44454 554 2338.05 44988 452 2343.57 45686 454 2349.60 46243 438 2355.06 46598 457 2354.55 46563 477 2360.56 47080 443 2365.57 47491 452 2371.56 47997 478 2382.60 48934 505