Lake Qinghai Sediment Visible Reflectance Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!! NAME OF DATA SET: Lake Qinghai Sediment Visible Reflectance Data LAST UPDATE: 1/2009 (Original receipt by WDC Paleo) CONTRIBUTOR: Junfeng Ji, Nanjing University IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2009-004 WDC PALEO CONTRIBUTION SERIES CITATION: Ji, J., et al. 2009. Lake Qinghai Sediment Visible Reflectance Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2009-004. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Ji, J., J. Shen, W. Balsam, J. Chen, L. Liu, and X. Liu. 2005. Asian monsoon oscillations in the northeastern Qinghai–Tibet Plateau since the late glacial as interpreted from visible reflectance of Qinghai Lake sediments. Earth and Planetary Science Letters, Vol. 233, Issues 1-2, pp. 61-70, 30 April 2005. doi:10.1016/j.epsl.2005.02.025 ABSTRACT: Qinghai Lake is a large saline lake on the Qinghai-Tibetan Plateau of central Asia that is effected by both the Indian and Asian monsoons. We used reflectance spectroscopy to characterize the sediments in a 795-cm long core taken from the southeastern part of the lake. Sediment redness, which is related to iron oxide content, seems to monitor paleoclimatic changes in the core. Iron oxides appear to be eroded from nearby red beds or loess deposits and are transported by fluvial means into the lake. Thus, redness increases at times of increased precipitation, that is, as monsoon strength increases. Our redness monsoon proxy shows climate changes on several times scales. On a millennial scale, it records humid conditions during the Early and Mid-Holocene. From about 4200 to 2300 yr BP, low redness values suggest a two-millennial long dry period, which in the Late Holocene is followed by a more humid period. On a centennial scale, the redness proxy records not only the Little Ice Age, but also the Medieval Warm Period, the Dark Ages Cool Period and the Roman Warm Period. Time series analysis of the redness record indicates a 200 yr frequency, which corresponds to the de Vries solar cycle suggesting that, in addition to insolation changes resulting from orbital variations, solar forcing also results from cyclic changes in the sun's luminosity. GEOGRAPHIC REGION: Central China PERIOD OF RECORD: 17KYrBP - present FUNDING SOURCES: National Basic Research Program of China and National Natural Science Foundation of China DESCRIPTION: Sediment optical properties (brightness and %redness) data from a core in Lake Qinghai, central China, for the last 17,000 years. Sediment redness is a function of iron oxide content, eroded from nearby red beds or loess deposits, and thus is a proxy for increased precipitation and monsoon strength. Lake Qinghai core location: 36° 32'N, 99° 36'E, 3260m elevation, 22.3m water depth. DATA: Lake Qinghai sediment optical properties Column 1: Sample Depth (cm) Column 2: Age (cal.yr BP) Column 3: Brightness Column 4: %Redness Depth Age Brightness %Redness 1 31 2013 27.37 2 63 2009 27.29 3 94 2000 27.54 4 125 2139 27.31 5 157 2329 26.91 6 188 2293 27.37 7 219 2076 27.68 8 251 2222 26.98 9 282 2147 27.10 10 313 2081 26.98 11 345 2136 27.27 12 376 1994 27.47 13 407 2012 27.06 14 439 2199 26.53 15 470 2373 26.10 16 501 2305 26.26 17 533 2250 26.03 18 564 2300 26.49 19 595 2227 25.98 20 627 2307 25.55 21 658 2285 25.50 22 689 2379 25.47 23 721 2261 25.56 24 752 2307 25.60 25 784 2204 25.77 26 815 2118 26.99 27 846 2058 26.87 28 878 2148 27.51 29 909 2338 26.97 30 940 2182 27.16 31 972 2216 27.24 32 1003 2192 27.22 33 1034 2163 27.08 34 1066 2172 27.16 35 1097 2313 26.71 36 1128 2211 26.58 37 1160 2118 27.07 38 1191 2130 27.48 39 1222 2237 26.67 40 1254 2048 26.42 41 1285 2164 27.35 42 1316 2270 26.97 43 1348 2193 27.04 44 1379 2295 26.86 45 1410 2326 26.86 46 1442 2118 27.04 47 1473 2206 27.10 48 1504 2281 27.01 49 1536 2238 26.97 50 1567 2197 27.10 51 1584 2230 27.15 52 1601 2169 26.96 53 1618 2149 27.53 54 1635 2064 26.28 55 1652 2167 25.89 56 1669 2176 26.79 57 1685 2161 27.05 58 1702 2133 27.24 59 1719 2155 27.38 60 1736 2281 26.85 61 1753 2238 26.94 62 1770 2144 27.26 63 1787 2244 26.15 64 1804 2327 25.71 65 1821 2321 25.64 66 1838 2440 25.35 69 1888 2377 25.64 70 1905 2415 25.40 71 1922 2299 25.61 72 1939 2267 26.09 73 1956 2341 26.22 74 1973 2274 26.26 75 1990 2266 26.30 76 2007 2220 26.23 77 2024 2268 26.22 78 2041 2110 26.42 79 2058 2194 26.31 80 2075 2156 26.33 81 2092 2188 26.56 82 2108 1942 27.67 83 2125 1827 27.85 84 2142 2028 27.66 85 2159 2174 27.09 86 2176 2147 26.98 87 2193 2304 26.95 88 2210 2255 27.28 89 2227 2288 27.05 90 2244 1842 27.63 91 2261 1925 26.74 92 2278 1931 27.04 93 2295 2330 26.42 94 2311 2621 26.14 95 2328 2489 26.31 96 2345 2576 26.10 98 2379 2503 25.63 99 2396 2382 25.24 100 2413 2418 25.17 101 2430 2531 25.14 102 2447 2636 25.11 103 2464 2617 24.80 104 2481 2568 24.82 105 2498 2552 24.82 106 2515 2553 24.66 107 2531 2619 24.65 108 2548 2608 24.62 109 2565 2543 24.60 110 2582 2442 24.63 111 2599 2547 24.84 112 2616 2582 24.80 113 2633 2556 24.63 114 2650 2497 24.57 115 2667 2478 24.67 116 2684 2453 24.66 117 2701 2379 24.58 118 2718 2472 24.68 119 2734 2459 24.74 120 2751 2319 24.70 121 2768 2447 24.68 122 2785 2219 24.84 123 2802 2308 24.80 124 2819 2372 24.89 125 2836 2343 24.75 126 2853 2488 24.68 127 2870 2615 24.79 128 2887 2763 24.59 129 2904 2704 24.57 130 2921 2553 24.60 131 2938 2344 24.61 132 2954 2563 24.58 133 2971 2640 24.61 134 2988 2676 24.60 135 3005 2595 24.66 136 3022 2667 24.68 137 3039 2662 24.46 138 3056 2757 24.47 139 3073 2650 24.51 140 3090 2636 24.58 141 3107 2594 24.78 143 3141 2566 24.91 144 3157 2568 24.64 145 3174 2496 24.65 146 3191 2453 24.80 147 3208 2425 24.81 148 3225 2483 24.78 149 3242 2537 24.67 150 3259 2254 24.97 151 3275 2434 24.92 152 3290 2308 24.87 153 3306 2388 24.77 154 3321 2405 24.99 155 3337 2482 24.93 156 3352 2564 24.86 158 3384 2600 24.75 159 3399 2539 24.57 160 3415 2445 24.74 161 3430 2525 24.71 162 3446 2556 24.72 163 3461 2615 24.71 164 3477 2691 24.53 165 3493 2606 24.60 166 3508 2529 24.48 167 3524 2503 24.55 168 3539 2548 24.70 169 3555 2605 24.78 170 3571 2627 24.72 171 3586 2497 24.98 172 3602 2630 24.92 173 3617 2572 24.97 174 3633 2490 25.11 175 3648 2487 24.99 176 3664 2634 24.82 177 3680 2415 24.81 178 3695 2455 25.09 179 3711 2390 25.24 180 3726 2286 25.28 181 3742 2406 25.11 182 3757 2365 24.99 183 3773 2442 24.82 184 3789 2557 24.84 185 3804 2494 24.69 186 3820 2448 24.65 187 3835 2421 24.85 188 3851 2460 24.93 189 3866 2511 24.92 190 3882 2423 24.64 191 3898 2675 24.76 192 3913 2653 24.93 193 3929 2652 24.80 194 3944 2593 24.87 195 3960 2616 24.70 196 3975 2671 24.78 197 3991 2614 24.80 198 4007 2704 25.02 199 4022 2677 24.83 200 4038 2420 25.34 201 4053 2674 24.85 202 4069 2717 24.82 203 4084 2766 24.70 204 4100 2498 24.96 205 4116 2810 24.72 206 4131 2683 24.92 207 4147 2410 25.80 208 4162 2374 25.77 209 4178 1678 27.64 210 4194 2277 25.96 211 4209 2541 25.69 212 4225 2534 25.22 213 4240 2183 26.39 214 4256 2349 26.48 215 4271 2477 26.35 216 4287 2572 25.53 217 4303 2945 25.23 218 4318 2788 25.35 219 4334 2698 25.33 220 4349 2488 25.37 221 4365 2477 25.56 222 4380 2453 25.75 223 4396 2457 25.72 224 4412 2323 25.85 225 4427 2468 25.78 226 4443 2313 25.97 227 4458 2257 25.83 228 4474 2464 25.68 229 4489 2704 25.47 230 4505 2527 25.34 231 4521 2491 26.06 232 4537 2536 26.22 233 4554 3394 24.76 234 4570 2831 25.01 236 4602 2780 25.06 237 4618 2824 24.78 238 4634 2847 24.77 239 4651 2864 24.73 240 4667 2669 24.72 241 4683 2901 24.62 242 4699 2740 24.80 243 4715 1595 27.04 244 4732 1880 27.74 245 4748 1814 27.18 246 4764 2357 26.61 247 4780 2678 26.00 248 4796 3036 25.40 249 4812 2848 25.23 250 4829 2788 25.06 257 4942 2395 25.78 259 4974 2359 25.82 261 5007 2601 25.62 263 5039 2689 24.86 265 5071 2815 24.84 267 5104 2838 24.83 269 5136 2537 25.00 271 5169 1685 27.56 273 5201 2228 26.77 277 5266 2814 25.16 279 5298 2851 25.02 281 5330 2568 25.05 283 5363 1753 26.07 287 5427 2663 25.56 289 5460 2621 25.28 291 5492 2587 25.11 293 5525 2452 25.10 295 5557 2443 25.06 297 5589 2434 25.06 299 5622 2342 24.92 301 5654 2566 25.39 303 5686 2433 26.09 305 5719 2533 25.40 307 5751 2882 25.23 309 5784 2827 24.74 311 5816 2875 24.94 313 5848 2374 25.42 315 5881 1432 26.93 317 5913 1727 26.87 319 5945 1877 26.92 321 5978 2041 26.26 323 6010 3057 25.01 325 6042 2769 24.86 327 6075 2752 24.84 329 6107 2168 25.34 331 6140 1909 26.48 333 6172 1726 27.02 335 6204 1767 26.97 337 6237 2444 26.31 339 6269 2754 25.33 341 6301 1499 27.62 343 6334 1904 27.45 345 6366 2159 26.97 347 6399 2715 25.38 349 6431 1365 27.38 351 6463 2098 26.41 353 6496 1383 27.32 355 6528 1865 28.44 357 6580 1865 26.87 359 6632 2329 25.98 361 6685 2607 25.59 363 6737 2447 25.95 365 6789 2009 27.13 367 6841 1466 26.83 369 6894 2019 26.94 371 6946 1894 26.98 373 6998 1907 27.36 375 7050 1568 27.26 377 7102 1273 27.00 379 7155 1579 27.52 381 7207 1623 27.08 385 7311 1318 27.09 387 7363 1306 27.16 389 7416 2220 26.67 391 7468 3074 25.62 393 7520 2881 26.06 395 7572 3221 25.51 397 7625 2550 26.25 399 7677 1856 27.64 401 7729 1827 27.52 403 7781 1991 27.07 405 7833 1583 27.64 407 7886 1842 26.60 409 7938 1752 27.06 411 7990 2166 26.57 413 8042 1909 27.07 415 8094 2726 25.25 417 8147 2763 25.38 419 8199 2616 25.60 421 8251 2747 24.95 423 8303 2786 25.77 425 8356 2767 25.35 427 8408 2329 25.41 429 8460 2567 25.19 431 8512 2708 25.43 433 8564 2843 25.07 435 8617 2739 25.38 437 8669 2851 25.63 439 8721 3001 25.40 441 8773 2044 26.34 443 8826 1923 26.06 445 8878 1540 26.00 447 8930 2108 25.49 449 8982 1806 26.24 451 9034 2087 26.44 453 9087 2249 26.17 455 9139 1931 27.23 457 9191 2417 25.59 459 9243 2014 26.34 461 9295 2058 26.33 463 9348 1762 26.08 465 9400 1472 26.49 467 9452 1514 26.55 469 9504 1651 26.12 471 9557 1794 25.86 477 9730 1625 25.53 479 9799 1892 25.84 481 9867 1476 25.67 483 9936 1526 25.44 485 10005 1855 25.79 487 10074 1552 25.59 489 10143 1394 25.73 491 10211 1730 25.67 493 10280 2247 25.40 495 10349 2186 25.12 501 10555 2788 25.38 503 10624 2644 25.20 505 10693 2825 24.12 507 10762 2763 24.19 509 10830 2597 24.28 511 10899 2791 25.28 513 10968 2526 25.74 515 11037 2658 24.50 517 11106 2277 23.93 519 11174 2517 24.28 521 11243 2915 23.91 523 11312 2625 23.74 527 11450 2622 24.85 529 11518 2652 24.88 531 11587 2373 24.96 533 11656 2698 24.31 535 11725 2478 25.18 537 11793 2782 25.28 539 11862 2234 26.68 541 11931 2547 25.20 543 12000 2861 24.09 545 12069 2534 24.38 547 12137 2779 24.11 549 12206 2547 25.20 551 12275 2533 24.97 553 12344 2515 24.68 555 12413 2456 24.45 557 12481 2567 24.70 559 12550 2276 23.81 561 12619 3040 24.08 563 12688 2860 23.88 565 12757 2696 24.53 567 12825 2571 24.34 569 12894 2695 23.91 573 13032 2421 24.86 575 13101 2246 24.91 577 13169 2475 25.01 579 13238 1956 24.61 581 13307 2454 24.77 583 13376 2294 25.12 585 13444 2341 23.92 587 13513 2500 24.80 589 13582 2480 25.32 591 13651 2323 25.85 593 13720 2207 25.28 595 13788 2295 24.94 597 13857 2133 25.09 599 13926 2542 24.35 601 13995 2422 24.31 603 14064 2431 24.65 605 14132 2289 24.51 607 14201 2219 24.49 609 14270 2590 24.51 611 14339 2812 24.03 613 14408 2586 23.94 615 14476 2364 24.66 617 14545 2395 24.47 619 14614 2245 24.46 621 14683 2590 24.14 623 14751 2756 24.65 625 14820 2488 24.66 627 14889 2479 24.85 629 14958 2812 24.65 631 15027 2487 24.75 633 15095 2445 24.10 635 15164 2485 24.47 637 15233 2598 24.19 639 15302 2562 24.54 641 15371 2195 25.01 643 15439 2618 24.68 645 15508 2416 23.90 647 15577 2564 25.65 649 15646 2808 24.27 651 15715 2151 24.42 653 15783 2124 25.25 655 15852 1994 25.24 657 15921 2407 25.09 659 15990 2540 24.68 661 16058 2533 24.36 663 16127 2658 24.87 665 16196 2509 25.17 667 16265 2844 24.59 669 16334 2840 23.83 671 16402 2823 24.47 673 16471 2801 24.68 675 16540 2852 24.23 677 16566 2799 24.21 681 16618 2788 24.09 683 16644 2712 24.36 687 16697 2819 23.95 689 16723 2569 24.02 691 16749 2504 23.84 693 16775 2583 23.38 695 16801 2562 24.15 697 16827 2467 24.12 699 16853 2013 24.38 701 16879 2414 23.80 703 16906 2557 23.70 705 16932 2228 23.68 707 16958 1935 24.93 709 16984 2295 23.93 711 17010 2294 23.95 713 17036 2148 24.04 715 17062 2220 23.25 717 17088 2231 23.90 719 17115 2408 24.56 721 17141 2410 23.90 723 17167 2322 24.01 725 17193 2343 24.98 727 17219 2328 25.27 729 17245 2219 25.55 731 17271 2215 25.40 733 17297 2276 25.20 735 17323 2188 26.06 737 17350 2264 25.88 739 17376 2252 25.62 741 17402 2247 25.44 743 17428 2331 25.73 745 17454 2408 25.85