"Methane data from Brook et al., On the origin and timing of rapid changes in atmospheric methane during the last glacial period, " "Global Biogeochemical Cycles, 14(2), 559-572. " "The GISP2 gas age time scale is from Brook et al., Rapid changes in atmospheric methane during the past 110,000 years, " "Science, 273, 1087-1091. The Taylor Dome gas age time scale was derived by correlating the GISP2 and Taylor Dome methane records." Methane concentrations were determined by GC-FID using standards calibrated by NOAA CMDL. The gas age time scales and analytical techniques are described in further detail in the publication. GISP2 Depth (m) Methane (ppb) GISP2 Gas Age (ka) Taylor Dome Depth Taylor Dome Gas Age (ka) Methane (ppb) 116.3 739 0.133 90.12 0.8039 728 116.7 737 0.135 110.22 1.3231 668 117.3 753 0.138 130.12 1.8372 662 117.6 754 0.14 138.12 2.0438 659 147.1 730 0.273 142.42 2.1549 622 149.3 701 0.284 154.23 2.46 609 151.3 694 0.294 166.12 2.7671 620 154.1 704 0.306 178.1 3.0766 629 194.13 710 0.478 190.45 3.3956 593 214.3 700 0.565 201.26 3.6749 597 234.08 700 0.653 214.13 4.0074 609 274.1 715 0.83 226.13 4.3173 564 314.1 663 1.007 238.14 4.6276 558 344.1 682 1.145 246.14 4.8342 544 393 665 1.369 254.14 5.0409 545 415 659 1.481 268.56 5.4134 540 435 651 1.584 276.49 5.6183 539 455 654 1.679 284.5 5.8252 554 475.1 637 1.779 292.5 6.2009 534 499 655 1.902 301.5 6.6507 550 535.1 626 2.088 308.5 7.0005 584 555 639 2.193 316.5 7.4004 567 579 637 2.32 324.75 7.8127 602 615.1 596 2.51 332.5 8.2 589 634.1 615 2.615 334.5 8.3 572 655.1 665 2.73 336.5 8.5 609 736.1 647 3.198 338.5 8.7 618 755.1 590 3.31 339.5 8.7783 674 756 617 3.315 341.63 8.8989 655 774.47 607 3.428 341.87 8.9302 640 836.15 606 3.804 343.5 9.1543 621 874.1 609 4.035 344.5 9.2918 656 919.7 598 4.328 345.5 9.4292 666 943.07 610 4.484 346 9.4979 662 974.15 598 4.69 346.5 9.5667 667 991.1 588 4.802 347.5 9.7041 675 1014.6 581 4.965 348.5 9.8416 671 1038.37 589 5.134 348.65 9.8622 666 1059 598 5.28 349.5 9.979 679 1074.2 592 5.387 350.5 10.1165 680 1114.54 587 5.698 351.5 10.254 711 1134.9 579 5.855 351.96 10.3172 689 1185.61 593 6.26 352.5 10.3914 701 1194.15 620 6.328 353.5 10.5289 759 1235.5 603 6.659 353.6 10.5426 710 1253.9 654 6.816 354.5 10.6663 689 1274.79 644 6.995 354.6 10.6801 690 1296.54 635 7.181 355.5 10.8038 674 1334.9 634 7.51 356.5 10.9571 671 1354.9 621 7.688 356.86 11.0257 654 1375.1 613 7.867 356.86 11.0257 673 1415.1 566 8.233 357.5 11.1476 684 1435 657 8.431 357.74 11.1933 687 1455.1 662 8.631 358.5 11.3211 669 1475.1 727 8.828 359.5 11.4263 624 1495 653 9.026 360.58 11.54 674 1516.1 659 9.243 361.5 11.6368 660 1535 682 9.451 362 11.6895 662 1554 710 9.664 362.5 11.7321 497 1575.1 749 9.914 362.95 11.7682 513 1595 749 10.153 363.48 11.8107 477 1601.9 703 10.236 364.01 11.8533 465 1608.1 742 10.311 364.5 11.8926 432 1615 708 10.399 364.87 11.9223 482 1621.9 701 10.493 365.5 11.9728 477 1628.2 720 10.579 366.05 12.017 473 1635 716 10.672 366.5 12.0531 435 1648 732 10.857 367.5 12.1333 483 1655 732 10.957 367.93 12.1678 480 1661.9 724 11.061 369.4 12.2858 490 1668.2 741 11.157 370.5 12.6875 523 1675.1 738 11.261 370.85 12.8311 532 1680.12 680 11.369 371.5 12.912 598 1681.9 681 11.407 372 13.076 659 1685 693 11.458 373.07 13.427 633 1687.9 709 11.505 373.5 13.568 668 1688.2 737 11.51 373.98 13.7254 651 1691.15 751 11.557 374.4 13.8632 662 1693 755 11.589 374.66 13.9485 614 1695.1 769 11.626 375.1 14.0928 604 1695.7 686 11.641 375.5 14.224 604 1696.12 738 11.652 376.05 14.4044 621 1696.12 737 11.652 376.5 14.552 568 1697 693 11.675 377 14.716 601 1698 625 11.703 377.5 14.88 507 1699 591 11.729 378 15.51 500 1700.12 536 11.761 378.51 16.1526 442 1700.58 520 11.776 379 16.77 495 1701.11 508 11.792 379.5 17.4 383 1701.5 534 11.805 380 18.3468 377 1702 489 11.822 380.77 19.8049 359 1704.12 485 11.901 381.7 21.566 369 1705 521 11.932 382.5 23.0809 357 1706.12 481 11.972 383.5 24.9745 346 1706.9 495 11.999 384.5 26.4717 420 1706.9 540 11.999 386.5 27.6167 370 1708.5 525 12.054 387.74 28.3265 379 1710.13 484 12.11 388.5 28.7616 379 1711.2 458 12.146 389.5 29.3341 392 1713 492 12.196 390.5 29.9065 425 1715.1 510 12.255 391.5 30.479 450 1719 488 12.396 392.5 31.0514 392 1721.9 497 12.5 393.5 31.6239 410 1721.9 491 12.5 395.5 32.7688 400 1725 476 12.647 397.73 34.0454 433 1728.2 597 12.799 399.5 34.75 500 1728.7 585 12.822 401.86 35.5867 412 1732.12 626 12.912 403.58 36.16 425 1735.1 703 12.991 404.5 36.4528 516 1739 680 13.083 406.56 37.0822 558 1741.9 618 13.151 407.6 37.4 516 1746.12 674 13.263 408.59 37.7025 517 1749.2 685 13.344 411.04 38.4511 536 1752.12 684 13.421 411.5 38.6081 463 1755 675 13.497 412.5 38.9685 419 1762.12 674 13.651 413.5 39.3289 413 1768.2 666 13.783 414.64 39.7398 431 1768.2 648 13.783 415.5 40.0497 418 1772.12 704 13.861 416.66 40.4678 429 1775.1 651 13.921 417.5 40.7705 417 1779 640 14.006 418.5 41.1309 441 1781.2 626 14.054 419.6 41.5273 428 1781.9 701 14.069 420.51 41.8553 428 1786.12 625 14.161 421.5 42.2121 452 1786.12 630 14.161 422.5 42.5725 412 1789.2 661 14.228 423.68 42.9977 406 1790.12 632 14.246 425.68 43.7185 481 1791.11 615 14.265 427.54 44.3889 415 1792.1 618 14.284 430.53 45.4665 456 1793.12 636 14.303 432.52 46.1836 465 1794.2 661 14.324 433.5 46.5368 435 1795.1 667 14.343 435.56 47.2792 409 1796 622 14.364 438.8 48.4469 486 1798 626 14.411 439.5 48.6992 506 1799.12 648 14.437 440.86 49.1893 489 1799.12 654 14.437 442.98 49.9534 515 1800 658 14.458 444.52 50.5084 474 1801.2 622 14.486 446.99 51.3986 496 1802.12 605 14.501 448.23 51.8455 446 1803 638 14.516 449.5 52.3032 461 1803.9 612 14.531 451.5 53.024 501 1805.12 613 14.551 453.5 53.7448 529 1808.2 624 14.603 455.66 54.5232 501 1812 621 14.666 456.5 54.8259 446 1815.1 593 14.718 457.6 55.2224 488 1818 583 14.82 459.4 55.8711 586 1821.11 490 14.93 461.67 56.6892 486 1824 490 15.032 462.8 57.1849 502 1827 458 15.138 463.5 57.4935 495 1828.1 482 15.177 464.63 57.9917 415 1829.9 538 15.245 465.43 58.3444 448 1833.14 466 15.367 466.5 58.8161 434 1833.14 476 15.367 467.43 59.2261 427 1835.1 481 15.44 468.43 59.667 496 1841.3 458 15.684 470.63 60.6369 502 1848.1 486 15.951 472.51 61.4657 447 1855.1 462 16.225 474.7 62.4312 473 1861.9 440 16.507 475.5 62.7839 468 1868.2 450 16.767 476.61 63.2732 457 1878.2 404 17.263 478.4 64.0624 451 1882.1 370 17.477 478.5 64.1065 445 1888.1 360 17.806 479.5 64.5473 450 1895.1 406 18.19 481.19 65.3816 458 1902.1 380 18.587 482.76 66.2313 455 1908 356 18.864 484.65 67.2541 475 1915.1 396 19.163 485.73 67.8386 462 1928.1 403 19.751 488.97 69.6165 432 1935.1 394 20.069 490.54 70.6922 471 1942 410 20.423 490.67 70.7813 476 1948 371 20.731 492.48 72.0215 478 1975.1 413 22.123 497.23 76.5874 438 1995 425 23.123 500.17 79.8742 490 2002 395 23.298 501.4 81.2492 567 2015 414 24.288 502.34 82.3001 548 2035.1 384 25.786 503.86 83.9994 638 2042 393 26.256 504.16 84.2299 467 2048 362 26.672 505.22 84.8858 443 2061 389 27.653 508.81 87.1069 416 2068 459 27.844 510.39 88.0845 523 2088 490 28.886 510.87 88.3814 489 2102 412 29.549 511.29 89.0524 473 2108 396 29.987 511.69 89.7215 462 2115.1 466 30.46 512.3 90.7418 467 2122 427 31.326 512.85 91.6618 452 2135.1 525 32.062 514.08 93.7193 436 2148.1 462 33.244 514.3 94.0873 460 2155.1 542 33.452 514.86 95.024 445 2162 430 33.692 514.96 95.1913 443 2168.1 443 34.213 515.35 95.8436 447 2175.1 590 34.737 515.83 96.6465 484 2188.1 583 35.072 516.3 97.4327 472 2195.1 444 35.334 516.86 98.14 494 2202 461 36.112 517.3 98.6565 531 2208 533 36.538 518.27 99.7952 526 2210 500 36.679 518.78 100.394 468 2215.1 577 37.041 519.27 100.969 474 2218 571 37.221 519.67 101.439 537 2220 555 37.346 520.28 102.155 614 2222 578 37.47 520.72 102.671 603 2224 554 37.595 521.28 103.395 435 2226 561 37.728 521.75 104.059 464 2228.1 571 37.868 522.28 104.807 468 2229.9 560 37.951 522.68 105.371 460 2232 584 38.049 523.28 106.218 509 2232.9 575 38.091 523.78 106.923 493 2234 560 38.142 524.91 108.518 503 2235 623 38.166 525.48 109.323 511 2236 571 38.192 525.81 109.788 544 2237 586 38.219 526.45 110.692 489 2238.9 582 38.269 526.84 111.242 490 2240 605 38.298 527.33 111.934 562 2240.9 594 38.321 527.75 112.526 577 2240.9 595 38.321 528.45 113.572 597 2241.95 610 38.349 528.99 117.439 580 2242.5 577 38.386 529.49 121.02 605 2243 584 38.419 529.89 123.885 632 2243.5 599 38.452 530.39 127.798 695 2244 550 38.486 2244.5 507 38.519 2245 486 38.552 2245.5 537 38.585 2246 466 38.619 2249.9 460 38.913 2252 463 39.09 2254 403 39.291 2256 461 39.521 2257.9 433 39.621 2261.9 452 39.832 2265.9 471 40.043 2271.9 442 40.415 2277.9 489 40.8 2281.9 500 40.91 2287.9 433 41.094 2293.9 408 41.59 2297.9 458 41.873 2304 486 42.162 2309.9 514 42.305 2313.9 474 42.406 2319.9 414 42.88 2323.9 434 43.207 2325.9 474 43.331 2327.9 439 43.47 2330 470 43.607 2331.9 431 43.725 2333.9 473 43.836 2335.9 497 43.958 2337.9 478 44.087 2339.9 478 44.196 2341.9 482 44.296 2343.9 487 44.382 2345.9 514 44.477 2347.9 491 44.58 2349.9 489 44.684 2351.9 534 44.776 2354 530 44.876 2355.9 511 44.967 2358.15 520 45.047 2359.9 508 45.11 2362.15 537 45.164 2363.15 550 45.188 2363.9 533 45.206 2364.65 554 45.231 2365.15 548 45.248 2365.65 587 45.265 2366.65 570 45.298 2367.1 564 45.313 2367.5 575 45.327 2367.9 528 45.34 2368.65 481 45.397 2368.92 544 45.418 2370.15 558 45.512 2370.65 521 45.55 2371.6 515 45.623 2372.15 506 45.665 2372.65 472 45.703 2373.15 491 45.741 2373.9 460 45.799 2378 454 46.195 2383.9 450 46.685 2399.9 486 47.634 2405.9 462 48.047 2409.9 482 48.308 2416 515 48.748 2421.9 501 49.132 2425.9 527 49.386 2431.9 536 49.925 2437.9 548 50.461 2441.9 548 50.777 2453.9 546 51.778 2453.9 533 51.778 2458 555 52.012 2461.9 515 52.434 2465.9 438 53.08 2470 493 53.568 2471.9 561 53.743 2473.9 549 53.988 2481.8 538 55.134 2485.9 547 55.615 2492 581 56.305 2493.9 573 56.456 2497.9 629 56.84 2499.9 562 57.147 2501.9 481 57.396 2503.9 592 57.591 2506 597 57.794 2507.9 602 57.954 2510 507 58.077 2511.9 589 58.212 2513.9 452 58.425 2515.9 402 58.664 2518 461 58.921 2519.9 435 59.141 2521.9 466 59.37 2525.9 489 59.777 2530 450 60.327 2532 460 60.778 2533.9 454 61.218 2534.87 476 61.422 2537.87 521 61.696 2539.85 538 61.817 2541.9 469 61.94 2543.9 464 62.092 2545.9 524 62.3 2547.9 452 62.584 2549.9 504 62.874 2551.9 432 63.146 2553.9 512 63.373 2555.9 490 63.564 2557.9 457 63.817 2559.9 490 64.241 2561.9 464 64.873 2563.9 512 65.263 2565.9 467 65.438 2567.9 509 65.691 2569.9 448 66.233 2571.9 446 66.741 2573.9 474 67.037 2577.9 488 67.582 2581.9 506 68.125 2585.9 488 68.413 2589.9 453 68.471 2594 454 69.736 2597.9 463 70.519 2599.9 467 70.852 2601.9 440 71.186 2605.9 512 71.824 2607.9 457 72.146 2609.9 472 72.441 2614 497 72.747 2617.9 448 72.998 2619.9 416 73.664 2621.9 454 74.118 2626 443 74.82 2629.9 577 75.482 2631.9 475 75.778 2633.9 461 76.097 2637.9 573 76.739 2639.9 510 77.069 2641.9 506 77.372 2643.9 522 77.686 2645.9 514 78.032 2649.9 574 78.708 2651.9 559 79.04 2653.9 590 79.406 2655.9 580 79.779 2657.9 577 80.156 2659.9 591 80.543 2661.9 591 80.924 2664 649 81.326 2666.9 639 81.89 2667.9 726 82.083 2671.9 710 82.868 2673.9 666 83.283 2675.9 736 83.624 2677.9 710 83.956 2679.9 505 84.347 2682 464 84.725 2685.9 462 85.495 2685.9 441 85.495 2688 526 85.889 2689.9 462 86.293 2691.9 449 86.876 2691.9 485 86.876 2693.9 512 87.439 2696 494 87.939 2697.9 505 88.382 2699.9 487 88.861 2701.9 534 89.322 2703.9 495 89.73 2705.9 447 90.134 2707.9 444 90.58 2709.9 449 91.026 2711.9 443 91.487 2713.9 430 91.983 2715.9 470 92.477 2718 488 93.012 2719.9 525 93.529 2721.9 430 94.051 2723.9 464 94.582 2725.9 476 95.101 2729.9 528 96.14 2731.9 513 96.687 2733.92 535 97.215 2736 588 97.745 2739.9 584 98.697 2741.9 572 99.145 2744 548 99.61 2745.9 566 99.969 2748 561 100.315 2750 635 100.614 2751.9 640 100.958 2753.9 594 101.369 2756 502 101.794 2758 578 102.158 2759.9 643 102.507 2762 542 102.939 2764 447 103.333 2766 514 103.757 2768 501 104.184 2769.9 471 104.541 2772 512 104.933 2773.9 486 105.264 2775.9 487 105.572 2779.9 481 106.268 2781.9 475 106.624 2783.9 452 106.957 2785.9 536 107.322 2787.9 503 107.708 2789.9 557 108.116 2792 512 108.531 2793.5 570 108.655 2795.9 496 108.847 2797.9 561 109.007 2799.9 500 109.175