Perch and Dimple Lakes, Alaska 5000 Year Charcoal Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!! NAME OF DATA SET: Perch and Dimple Lakes, Alaska 5000 Year Charcoal Data LAST UPDATE: 10/2011 (Original receipt by WDC Paleo) CONTRIBUTORS: Hu, F.S., P.E. Higuera, J.E. Walsh, W.L. Chapman, P.A. Duffy, L.B. Brubaker, and M.L. Chipman IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2011-131 WDC PALEO CONTRIBUTION SERIES CITATION: Hu, F.S., et al. 2011. Perch and Dimple Lakes, Alaska 5000 Year Charcoal Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2011-131. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Hu, F.S., P.E. Higuera, J.E. Walsh, W.L. Chapman, P.A. Duffy, L.B. Brubaker, and M.L. Chipman. 2010. Tundra burning in Alaska: Linkages to climatic change and sea ice retreat. J. Geophys. Res., 115, G04002, doi:10.1029/2009JG001270. ABSTRACT: Recent climatic warming has resulted in pronounced environmental changes in the Arctic, including shrub cover expansion and sea ice shrinkage. These changes foreshadow more dramatic impacts that will occur if the warming trend continues. Among the major challenges in anticipating these impacts are "surprises" stemming from changes in system components that have remained relatively stable in the historic record. Tundra burning is potentially one such component. Here we report paleoecological evidence showing that recent tundra burning is unprecedented in the central Alaskan Arctic within the last 5000 years. Analysis of lake sediment cores reveals peak values of charcoal accumulation corresponding to the Anaktuvuk River Fire in 2007, with no evidence of other fire events throughout the past five millennia in that area. Atmospheric reanalysis suggests that the fire was favored by exceptionally warm and dry weather conditions in summer and early autumn. Boosted regression tree modeling shows that such conditions also explain 95% of the interannual variability in tundra area burned throughout Alaska over the past 60 years and that the response of tundra burning to climatic warming is nonlinear. These results contribute to an emerging body of evidence suggesting that tundra ecosystems can burn more frequently under suitable climatic and fuel conditions. The Anaktuvuk River Fire coincides with extreme sea ice retreat, and tundra area burned in Alaska is moderately correlated with sea ice extent from 1979 to 2009 (r = -0.43, p = 0.02). Recurrences of large tundra fires as a result of sea ice disappearance may represent a novel manifestation of coupled marine-terrestrial responses to climatic warming. GEOGRAPHIC REGION: Northwestern North America PERIOD OF RECORD: 5000 YrBP - present FUNDING SOURCES: US National Science Foundation (NSF) ARC 0612366 and OPP 05-20112, Joint Fire Science Program (06-3-1-23). DESCRIPTION: Chronology, magnetic susceptibility, and macrosopic charcoal (number of pieces >180 microns) from sediments of Dimple and Perch Lakes, North Slope, Alaska. Also included are modern and reanalysis data used to generate Figures 2a, 2b, 3, and 4a of Hu et al. 2010. Perch Lake, Alaska: 68.94°N, 150.50°W Dimple Lake, Alaska: 68.95°N, 150.20°W DATA: 1. Lead-210 modelled ages and Radiocarbon material, 14C ages, and calibrated ages from Perch Lake 1a. Perch 210Pb depth_up top depth of interval in cm depth_down bottom depth of interval in cm age_down Age in BP up_CI upper 95% CI in BP low_CI lower 95% CI in BP depth_up depth_down age up_CI low_CI 0 1 -58 -56 -60 1 2 -56 -54 -58 2 3 -43 -40 -46 3 4 -25 -21 -29 4 5 -2 5 -9 5 6 28 41 15 6 7 55 82 28 1b. Perch 14C depth_up top depth of interval in cm depth_down bottom depth of interval in cm age_14C raw 14C-age estimate in years BP error_14C 2 sigma error estimate of 14C age age_calBP mean calibrated 14C-age estimate in cal BP up_CI_calBP upper 95% CI of calibrated age low_CI_calBP lower 95% CI of calibrated age comments description of material used for AMS analysis depth_up depth_down age_14C error_14C age_calBP up_CI_calBPlow_CI_calB comments 14 14.25 295 35 382 290 462 wood 29.75 30 925 35 847 751 919 small twig 50 50.25 2460 35 2538 2368 2701 small twig 73.25 73.5 3560 60 3853 3697 4048 small twig 2. Perch Charcoal depth_up top depth of interval in cm depth_down bottom depth of interval in cm age_up Age at the top of the interval in cal BP age_down Age at the bottom of the interval in cal BP Char_vol Volume of wet sediment used for charcoal counts (cm3) Char_count # of charcoal pieces >180 um MS volume magnetic susceptibility (?, dimensionless) BulkD sediment bulk density - g dry sediment per volume (g/cm3) depth_up depth_down age_up age_down Char_vol Char_count MS BulkD 0 0.5 -58 -57 3 9 0.00 0.01 0.5 1 -57 -56 3 20 0.50 0.08 1 1.5 -56 -50 3 0 1.00 0.22 1.5 2 -50 -43 3 0 1.20 0.26 2 2.5 -43 -34 3 0 1.35 0.29 2.5 3 -34 -25 3 0 1.45 0.32 3 3.5 -25 -15 3 0 1.60 0.32 3.5 4 -15 -2 3 0 2.10 0.49 4 4.5 -2 13 3 0 2.00 0.45 4.5 5 13 28 3 0 1.90 0.47 5 5.5 28 41 3 0 2.30 0.63 5.5 6 41 55 3 0 2.25 0.51 6 6.5 55 73 3 0 2.35 0.44 6.5 7 73 95 3 0 2.20 0.39 7 7.5 95 108 3 0 2.30 0.45 7.5 8 108 125 3 0 2.10 0.36 8 8.5 125 141 3 0 2.45 0.45 8.5 9 141 159 3 0 2.65 0.59 9 9.5 159 176 3 1 2.70 0.56 9.5 10 176 193 3 0 2.55 0.59 10 10.25 193 201 0.5 0 0.70 0.58 10.25 10.5 201 210 1 0 0.95 0.81 10.5 10.75 210 218 2 0 1.80 0.61 10.75 11 218 227 2 0 1.75 0.59 11 11.25 227 235 2 0 1.95 0.59 11.25 11.5 235 244 2 0 1.80 0.56 11.5 11.75 244 253 2 1 1.65 0.55 11.75 12 253 261 2 0 1.85 0.53 12 12.25 261 270 3 0 2.85 0.61 12.25 12.5 270 278 3 0 2.80 0.58 12.5 12.75 278 287 2 0 2.00 0.59 12.75 13 287 296 2.5 0 2.40 0.60 13 13.25 296 304 3 0 2.90 0.63 13.25 13.5 304 313 3 0 2.90 0.63 13.5 13.75 313 322 3 0 2.75 0.70 13.75 14 322 331 3 0 2.80 0.59 14 14.25 331 339 2 0 1.85 0.77 14.25 14.5 339 348 2 0 2.85 0.81 14.5 14.75 348 357 2 0 1.90 0.70 14.75 15 357 366 2.5 0 2.40 0.68 15 15.25 366 374 3 1 2.85 0.73 15.25 15.5 374 383 3 0 2.90 0.68 15.5 15.75 383 392 3 0 2.75 0.73 15.75 16 392 401 2.5 0 2.55 0.67 16 16.25 401 410 2.5 0 2.50 0.80 16.25 16.5 410 419 3 0 2.95 0.66 16.5 16.75 419 428 3 0 3.05 0.67 16.75 17 428 437 3 0 3.15 0.66 17 17.25 437 446 3 0 3.15 0.62 17.25 17.5 446 455 3 0 3.05 0.61 17.5 17.75 455 465 3 0 3.35 0.64 17.75 18 465 474 3 0 3.05 0.62 18 18.25 474 483 3 0 3.00 0.68 18.25 18.5 483 492 3 0 3.10 0.68 18.5 18.75 492 502 2 0 2.20 0.67 18.75 19 502 511 3 0 3.30 0.71 19 19.25 511 521 3 0 3.20 0.71 19.25 19.5 521 530 3 0 3.20 0.78 19.5 19.75 530 540 3 0 3.30 0.81 19.75 20 540 550 3 0 3.25 0.65 20 20.25 550 559 3 0 3.30 0.63 20.25 20.5 559 569 3 0 3.40 0.67 20.5 20.75 569 579 3 0 3.35 0.59 20.75 21 579 589 3 0 3.10 0.56 21 21.25 589 599 3 0 3.20 0.60 21.25 21.5 599 609 3 1 3.05 0.64 21.5 21.75 609 619 3 0 3.10 0.66 21.75 22 619 629 3 0 3.00 0.69 22 22.25 629 639 3 0 3.25 0.71 22.25 22.5 639 650 3 0 3.25 0.65 22.5 22.75 650 660 3 0 3.20 0.67 22.75 23 660 671 3 0 3.00 0.59 23 23.25 671 681 3 0 3.05 0.48 23.25 23.5 681 692 3 0 3.05 0.53 23.5 23.75 692 703 3 0 2.90 0.53 23.75 24 703 714 2 0 2.05 0.55 24 24.25 714 725 3 0 3.00 0.55 24.25 24.5 725 736 3 0 2.95 0.60 24.5 24.75 736 747 3 0 3.00 0.62 24.75 25 747 758 3 0 3.25 0.65 25 25.25 758 769 3 0 3.15 0.69 25.25 25.5 769 781 3 0 2.85 0.66 25.5 25.75 781 792 3 0 2.85 0.66 25.75 26 792 804 3 0 3.20 0.74 26 26.25 804 816 3 0 3.20 0.68 26.25 26.5 816 827 3 0 3.05 0.62 26.5 26.75 827 839 3 0 10.40 0.60 26.75 27 839 851 3 0 2.10 0.60 27 27.25 851 864 3 0 2.70 0.60 27.25 27.5 864 876 3 0 2.65 0.58 27.5 27.75 876 888 3 0 2.10 0.60 27.75 28 888 901 3 0 2.95 0.62 28 28.25 901 914 3 0 2.75 0.64 28.25 28.5 914 926 3 0 3.20 0.70 28.5 28.75 926 939 3 0 3.00 0.67 28.75 29 939 952 3 0 3.20 0.67 29 29.25 952 965 3 0 3.15 0.65 29.25 29.5 965 979 3 0 3.00 0.63 29.5 29.75 979 992 3 0 3.00 0.63 29.75 30 992 1006 3 0 3.05 0.66 30 30.25 1006 1019 3 0 3.10 0.71 30.25 30.5 1019 1033 3 0 2.90 0.70 30.5 30.75 1033 1047 3 0 3.15 0.68 30.75 31 1047 1061 3 1 3.15 0.68 31 31.25 1061 1075 3 0 3.15 0.68 31.25 31.5 1075 1089 3 0 3.15 0.66 31.5 31.75 1089 1104 3 0 3.10 0.65 31.75 32 1104 1118 3 0 3.00 0.63 32 32.25 1118 1133 3 0 3.10 0.63 32.25 32.5 1133 1148 3 0 2.95 0.63 32.5 32.75 1148 1163 3 0 2.55 0.64 32.75 33 1163 1178 3 0 2.85 0.66 33 33.25 1178 1193 3 0 2.85 0.67 33.25 33.5 1193 1208 3 0 2.65 0.65 33.5 33.75 1208 1223 3 0 2.80 0.66 33.75 34 1223 1239 3 0 2.90 0.68 34 34.25 1239 1254 3 0 2.80 0.69 34.25 34.5 1254 1270 3 0 2.85 0.70 34.5 34.75 1270 1286 3 0 2.85 0.70 34.75 35 1286 1301 3 0 3.00 0.70 35 35.25 1301 1317 3 0 3.00 0.70 35.25 35.5 1317 1333 3 0 2.85 0.68 35.5 35.75 1333 1349 3 0 2.85 0.68 35.75 36 1349 1365 3 0 2.90 0.68 36 36.25 1365 1382 3 0 2.70 0.66 36.25 36.5 1382 1398 3 0 2.75 0.65 36.5 36.75 1398 1414 3 0 3.00 0.68 36.75 37 1414 1431 3 0 2.70 0.66 37 37.25 1431 1447 3 0 2.85 0.68 37.25 37.5 1447 1464 3 0 2.70 0.67 37.5 37.75 1464 1481 3 0 2.65 0.66 37.75 38 1481 1497 3 0 2.70 0.69 38 38.25 1497 1514 3 0 2.80 0.70 38.25 38.5 1514 1531 3 0 2.75 0.68 38.5 38.75 1531 1548 3 1 2.75 0.72 38.75 39 1548 1565 3 0 2.65 0.70 39 39.25 1565 1582 3 0 2.70 0.69 39.25 39.5 1582 1599 3 1 2.70 0.69 39.5 39.75 1599 1616 3 0 2.55 0.65 39.75 40 1616 1634 3 0 2.70 0.69 40 40.25 1634 1651 3 0 2.80 0.72 40.25 40.5 1651 1668 3 0 2.70 0.67 40.5 40.75 1668 1685 3 0 2.60 0.67 40.75 41 1685 1703 3 0 3.20 0.68 41 41.25 1703 1720 3 0 2.10 0.70 41.25 41.5 1720 1738 3 0 3.20 0.67 41.5 41.75 1738 1755 3 0 3.65 0.68 41.75 42 1755 1773 3 0 2.15 0.68 42 42.25 1773 1790 3 0 4.40 0.67 42.25 42.5 1790 1808 3 0 1.50 0.66 42.5 42.75 1808 1826 3 0 4.00 0.68 42.75 43 1826 1843 3 0 0.70 0.67 43 43.25 1843 1861 3 0 3.00 0.68 43.25 43.5 1861 1879 3 0 2.25 0.68 43.5 43.75 1879 1897 3 0 2.50 0.68 43.75 44 1897 1914 3 0 2.70 0.68 44 44.25 1914 1932 3 0 2.60 0.68 44.25 44.5 1932 1950 3 0 2.50 0.67 44.5 44.75 1950 1968 3 0 2.35 0.66 44.75 45 1968 1986 3 0 2.65 0.67 45 45.25 1986 2003 3 0 2.60 0.68 45.25 45.5 2003 2021 3 0 2.50 0.65 45.5 45.75 2021 2039 3 0 2.55 0.65 45.75 46 2039 2057 3 0 2.65 0.66 46 46.25 2057 2075 3 0 2.45 0.68 46.25 46.5 2075 2093 3 0 2.50 0.68 46.5 46.75 2093 2110 3 0 2.35 0.67 46.75 47 2110 2128 3 0 2.75 0.67 47 47.25 2128 2146 3 0 2.20 0.66 47.25 47.5 2146 2164 3 0 2.55 0.61 47.5 47.75 2164 2182 3 0 2.35 0.65 47.75 48 2182 2199 3 0 2.30 0.67 48 48.25 2199 2217 3 0 2.30 0.66 48.25 48.5 2217 2235 3 0 2.35 0.69 48.5 48.75 2235 2253 3 0 2.40 0.70 48.75 49 2253 2270 3 0 2.50 0.69 49 49.25 2270 2288 3 0 2.30 0.72 49.25 49.5 2288 2306 3 0 2.50 0.74 49.5 49.75 2306 2323 3 0 2.40 0.73 49.75 50 2323 2341 3 0 2.70 0.75 50 50.25 2341 2358 3 0 2.45 0.74 50.25 50.5 2358 2376 3 0 12.05 0.72 50.5 50.75 2376 2393 3 1 2.15 0.70 50.75 51 2393 2411 3 0 2.35 0.67 51 51.25 2411 2428 3 0 2.40 0.67 51.25 51.5 2428 2446 3 0 2.40 0.65 51.5 51.75 2446 2463 3 0 2.25 0.66 51.75 52 2463 2480 3 0 2.45 0.67 52 52.25 2480 2498 3 0 2.60 0.67 52.25 52.5 2498 2515 3 0 2.55 0.66 52.5 52.75 2515 2532 3 0 3.05 0.68 52.75 53 2532 2549 3 0 2.15 0.67 53 53.25 2549 2566 3 0 2.40 0.67 53.25 53.5 2566 2584 3 0 2.45 0.68 53.5 53.75 2584 2601 3 0 2.75 0.68 53.75 54 2601 2618 3 0 2.30 0.68 54 54.25 2618 2635 3 0 2.45 0.69 54.25 54.5 2635 2652 3 0 2.45 0.69 54.5 54.75 2652 2669 3 0 2.75 0.66 54.75 55 2669 2686 3 0 2.45 0.67 55 55.25 2686 2703 3 0 2.25 0.67 55.25 55.5 2703 2720 3 0 2.40 0.64 55.5 55.75 2720 2737 3 0 1.90 0.63 55.75 56 2737 2753 3 0 2.45 0.65 56 56.25 2753 2770 3 0 2.45 0.63 56.25 56.5 2770 2787 3 0 2.50 0.63 56.5 56.75 2787 2804 3 0 2.75 0.64 56.75 57 2804 2821 3 0 2.55 0.64 57 57.25 2821 2837 3 0 2.55 0.64 57.25 57.5 2837 2854 3 0 2.50 0.66 57.5 57.75 2854 2871 3 0 2.55 0.65 57.75 58 2871 2887 2.5 0 2.35 0.65 58 58.25 2887 2904 3 0 2.55 0.69 58.25 58.5 2904 2921 3 0 3.10 0.70 58.5 58.75 2921 2937 3 0 2.35 0.70 58.75 59 2937 2954 3 0 3.20 0.71 59 59.25 2954 2970 3 0 2.60 0.70 59.25 59.5 2970 2987 3 0 2.65 0.70 59.5 59.75 2987 3003 3 0 2.85 0.71 59.75 60 3003 3020 3 0 3.15 0.72 60 60.25 3020 3036 3 0 2.55 0.70 60.25 60.5 3036 3053 3 0 2.60 0.71 60.5 60.75 3053 3069 3 0 2.80 0.72 60.75 61 3069 3086 3 0 2.65 0.69 61 61.25 3086 3102 3 0 2.65 0.70 61.25 61.5 3102 3119 3 0 2.80 0.67 61.5 61.75 3119 3135 3 0 2.45 0.65 61.75 62 3135 3151 3 0 3.05 0.66 62 62.25 3151 3168 3 0 3.10 0.70 62.25 62.5 3168 3184 3 0 3.00 0.70 62.5 62.75 3184 3200 3 0 2.90 0.70 62.75 63 3200 3216 3 0 2.85 0.71 63 63.25 3216 3233 3 0 3.00 0.73 63.25 63.5 3233 3249 3 0 2.95 0.71 63.5 63.75 3249 3265 3 0 2.90 0.71 63.75 64 3265 3281 3 0 2.90 0.68 64 64.25 3281 3298 3 0 3.05 0.71 64.25 64.5 3298 3314 3 0 3.20 0.71 64.5 64.75 3314 3330 3 0 3.10 0.72 64.75 65 3330 3346 3 0 3.20 0.71 65 65.25 3346 3362 3 0 3.00 0.69 65.25 65.5 3362 3379 3 0 2.90 0.70 65.5 65.75 3379 3395 3 0 3.05 0.72 65.75 66 3395 3411 3 0 3.00 0.72 66 66.25 3411 3427 3 0 3.05 0.74 66.25 66.5 3427 3443 3 0 2.90 0.73 66.5 66.75 3443 3459 3 0 3.10 0.74 66.75 67 3459 3475 3 0 2.85 0.74 67 67.25 3475 3491 3 0 2.95 0.73 67.25 67.5 3491 3507 3 0 2.85 0.73 67.5 67.75 3507 3523 3 0 2.95 0.72 67.75 68 3523 3539 3 0 2.90 0.73 68 68.25 3539 3555 3 0 3.05 0.73 68.25 68.5 3555 3571 3 0 3.05 0.70 68.5 68.75 3571 3587 3 0 2.80 0.68 68.75 69 3587 3603 3 0 3.20 0.70 69 69.25 3603 3619 3 0 3.10 0.70 69.25 69.5 3619 3635 3 0 3.45 0.71 69.5 69.75 3635 3651 3 0 3.20 0.70 69.75 70 3651 3667 3 0 3.65 0.73 70 70.25 3667 3683 3 0 3.20 0.77 70.25 70.5 3683 3699 3 0 3.00 0.76 70.5 70.75 3699 3715 3 0 2.85 0.78 70.75 71 3715 3731 3 0 3.05 0.77 71 71.25 3731 3747 3 0 2.95 0.77 71.25 71.5 3747 3763 3 0 2.90 0.76 71.5 71.75 3763 3779 3 0 2.95 0.75 71.75 72 3779 3795 3 0 2.85 0.75 72 72.25 3795 3811 3 0 2.75 0.76 72.25 72.5 3811 3827 3 0 2.90 0.77 72.5 72.75 3827 3843 3 0 2.95 0.79 72.75 73 3843 3859 3 0 2.95 0.80 73 73.25 3859 3875 3 0 3.75 0.80 73.25 73.5 3875 3891 3 0 3.10 0.82 73.5 73.75 3891 3907 3 0 3.40 0.82 73.75 74 3907 3923 3 0 3.50 0.84 74 74.25 3923 3939 3 1 3.30 0.83 74.25 74.5 3939 3955 3 1 3.30 0.84 74.5 74.75 3955 3971 3 0 3.50 0.84 74.75 75 3971 3987 3 0 2.85 0.82 75 75.25 3987 4003 3 0 4.00 0.85 75.25 75.5 4003 4019 3 0 3.55 0.81 75.5 75.75 4019 4035 3 0 3.30 0.79 75.75 76 4035 4051 3 2 3.05 0.76 76 76.25 4051 4067 3 0 2.85 0.76 76.25 76.5 4067 4083 3 0 2.85 0.75 76.5 76.75 4083 4099 3 0 2.95 0.74 76.75 77 4099 4115 3 0 3.20 0.73 77 77.25 4115 4131 3 0 3.65 0.73 77.25 77.5 4131 4147 3 0 3.55 0.74 77.5 77.75 4147 4163 3 0 3.05 0.74 77.75 78 4163 4179 3 1 3.20 0.74 78 78.25 4179 4195 3 0 2.75 0.75 78.25 78.5 4195 4211 3 0 3.30 0.75 78.5 78.75 4211 4227 3 0 2.80 0.76 78.75 79 4227 4243 3 0 6.40 0.78 79 79.25 4243 4259 3 0 2.75 0.79 79.25 79.5 4259 4275 3 0 3.25 0.81 79.5 79.75 4275 4291 3 0 3.25 0.81 79.75 80 4291 4307 3 0 3.60 0.80 80 80.25 4307 4323 3 0 3.15 0.80 80.25 80.5 4323 4339 3 0 2.65 0.82 80.5 80.75 4339 4355 3 0 3.25 0.80 80.75 81 4355 4371 3 0 3.00 0.83 81 81.25 4371 4388 3 0 3.00 0.82 81.25 81.5 4388 4404 3 0 3.00 0.82 81.5 81.75 4404 4420 3 0 3.00 0.79 81.75 82 4420 4436 3 0 2.80 0.76 82 82.25 4436 4452 3 0 2.90 0.82 82.25 82.5 4452 4468 3 0 3.10 0.83 82.5 82.75 4468 4485 3 0 3.00 0.86 82.75 83 4485 4501 3 0 3.35 0.87 83 83.25 4501 4517 3 0 3.65 0.84 83.25 83.5 4517 4533 3 0 3.60 0.84 83.5 83.75 4533 4550 3 0 3.70 0.83 83.75 84 4550 4566 3 0 3.65 0.83 84 84.25 4566 4582 3 0 3.35 0.77 84.25 84.5 4582 4598 3 0 3.80 0.83 84.5 84.75 4598 4615 3 0 3.50 0.79 84.75 85 4615 4631 3 0 3.65 0.79 85 85.25 4631 4648 3 0 3.50 0.75 85.25 85.5 4648 4664 3 0 3.35 0.77 85.5 85.75 4664 4680 3 0 3.15 0.71 85.75 86 4680 4697 3 0 3.10 0.74 86 86.25 4697 4713 3 0 3.25 0.76 86.25 86.5 4713 4730 3 0 3.20 0.76 86.5 86.75 4730 4746 3 0 3.30 0.75 86.75 87 4746 4763 3 0 3.05 0.78 87 87.25 4763 4779 3 0 2.90 0.79 87.25 87.5 4779 4796 3 1 2.95 0.78 87.5 87.75 4796 4812 3 0 2.85 0.79 87.75 88 4812 4829 3 0 3.05 0.81 88 88.25 4829 4845 3 0 3.05 0.85 88.25 88.5 4845 4862 3 0 3.20 0.82 88.5 88.75 4862 4879 3 0 2.85 0.80 88.75 89 4879 4895 3 0 2.80 0.77 89 89.25 4895 4912 3 0 3.00 0.80 3. Lead-210 modelled ages and Radiocarbon material, 14C ages, and calibrated ages from Dimple Lake 3a. Dimple 210Pb depth_up top depth of interval in cm depth_down bottom depth of interval in cm age_down Age in BP up_CI upper 95% CI in BP low_CI lower 95% CI in BP depth_up depth_down age up_CI low_CI 0 1.5 -58 -57 -59 1.5 2.5 -57 -56 -58 2.5 3 -55 -54 -56 3 3.5 -54 -53 -55 3.5 4 -53 -51 -54 4 4.5 -51 -50 -52 4.5 5 -49 -48 -50 5 5.5 -48 -47 -49 5.5 6 -47 -45 -48 6 6.5 -44 -42 -45 6.5 7 -39 -38 -41 7 7.5 -36 -34 -37 7.5 8 -31 -30 -32 8 8.5 -28 -26 -30 8.5 9 -23 -22 -25 9 9.5 -19 -17 -21 9.5 10 -17 -15 -19 10 10.5 -17 -15 -18 10.5 11 -12 -10 -14 11 11.5 -6 -4 -8 11.5 12 -2 0 -4 12 12.5 6 8 4 12.5 13 13 15 11 13 13.5 18 20 15 13.5 14 24 27 22 14 14.5 30 34 26 14.5 15 39 43 36 15 15.5 46 50 41 15.5 16 55 59 51 16 16.5 55 62 49 3b. Dimple 14C depth_up top depth of interval in cm depth_down bottom depth of interval in cm age_14C raw 14C-age estimate in years BP error_14C 2 sigma error estimate of 14C age age_calBP mean calibrated 14C-age estimate in cal BP up_CI_calBP upper 95% CI of calibrated age low_CI_calBP lower 95% CI of calibrated age comments description of material used for AMS analysis *asterick date excluded from chronology depth_up depth_down age_14C error_14C age_calBP up_CI_calBPlow_CI_calBcomments 55.75 56.25 5825 45 6633* 6505 6735 wood 67.75 68 745 35 683 654 729 wood 68.5 69 775 35 701 670 759 wood 75.5 77.5 930 60 842 728 945 2 small twigs and wood 83 83.5 990 100 896 717 1136 wood 90.75 91 10910 280 12850* 12051 13316 very small twig 98.5 99 10220 60 11934* 11677 12159 2 small twigs 101 102 1220 50 1147 1009 1265 wood and bark fragments 4. Dimple Charcoal depth_up top depth of interval in cm depth_down bottom depth of interval in cm age_up Age at the top of the interval in cal BP age_down Age at the bottom of the interval in cal BP Char_vol Volume of wet sediment used for charcoal counts (cm3) Char_count # of charcoal pieces >180 um MS volume magnetic susceptibility (?, dimensionless) BulkD sediment bulk density - g dry sediment per volume (g/cm3) depth_up depth_down age_up age_down Char_vol Char_count MS BulkD 0 1.5 -58 -57 3 5 0.24 0.02 1.5 2 -57 -56 3 2 0.45 0.03 2 2.5 -56 -55 3 0 0.15 0.03 2.5 3 -55 -54 3 0 -0.20 0.05 3 3.5 -54 -53 3 0 -0.20 0.05 3.5 4 -53 -51 3 0 0.00 0.06 4 4.5 -51 -49 3 0 0.80 0.07 4.5 5 -49 -48 3 0 0.40 0.06 5 5.5 -48 -46 3 0 0.30 0.05 5.5 6 -46 -43 3 0 0.50 0.08 6 6.5 -43 -39 3 0 1.20 0.13 6.5 7 -39 -36 3 0 0.50 0.17 7 7.5 -36 -31 3 0 0.70 0.20 7.5 8 -31 -28 3 0 1.75 0.46 8 8.5 -28 -23 3 0 2.25 0.56 8.5 9 -23 -19 3 0 2.20 0.57 9 9.5 -19 -17 3 0 2.10 0.68 9.5 10 -17 -16 3 0 2.05 0.82 10 10.25 -16 -14 3 0 1.95 0.23 10.25 10.5 -14 -12 3 0 1.80 0.25 10.5 10.75 -12 -9 3 0 1.80 0.24 10.75 11 -9 -6 3 0 2.20 0.33 11 11.25 -6 -4 3 0 2.85 0.45 11.25 11.5 -4 -1 3 0 2.15 0.27 11.5 11.75 -1 2 3 0 2.10 0.20 11.75 12 2 6 3 0 2.30 0.22 12 12.25 6 10 2.5 0 1.40 0.19 12.25 12.5 10 13 3 0 1.65 0.16 12.5 12.75 13 16 3 0 1.75 0.19 12.75 13 16 18 3 0 2.20 0.21 13 13.25 18 21 3 0 2.30 0.24 13.25 13.5 21 24 3 0 2.30 0.22 13.5 13.75 24 27 3 0 1.75 0.18 13.75 14 27 30 3 0 1.75 0.16 14 14.25 30 34 3 0 1.90 0.19 14.25 14.5 34 39 3 0 2.30 0.29 14.5 14.75 39 43 3 0 2.15 0.24 14.75 15 43 47 3 0 2.35 0.23 15 15.25 47 51 3 0 1.95 0.18 15.25 15.5 51 54 3 0 1.90 0.22 15.5 15.75 54 55 3 0 2.00 0.25 15.75 16 55 56 3 0 2.10 0.28 16 16.25 56 58 3 0 2.50 0.38 16.25 16.5 58 60 3 1 2.85 0.28 16.5 16.75 60 62 2.02 0 1.65 0.27 16.75 17 62 65 2.5 0 2.35 0.30 17 17.25 65 68 1.5 0 1.25 0.28 17.25 17.5 68 71 2.5 0 2.20 0.28 17.5 17.75 71 74 2 0 1.65 0.29 17.75 18 74 77 2 0 1.60 0.27 18 18.25 77 80 2 1 1.70 0.30 18.25 18.5 80 82 1.5 0 1.40 0.31 18.5 18.75 82 85 2 0 1.90 0.32 18.75 19 85 88 2 0 1.80 0.31 19 19.25 88 91 2 0 1.80 0.32 19.25 19.5 91 94 2 0 1.45 0.33 19.5 19.75 94 97 2 0 1.75 0.36 19.75 20 97 100 3 0 3.10 0.39 20 20.25 100 102 3 0 3.30 0.41 20.25 20.5 102 105 3 0 3.40 0.41 20.5 20.75 105 108 3 0 3.37 0.42 20.75 21 108 111 3 0 3.40 0.41 21 21.25 111 114 3 0 2.85 0.35 21.25 21.5 114 117 3 0 3.45 0.43 21.5 21.75 117 120 3 0 3.45 0.42 21.75 22 120 122 3 0 3.65 0.44 22 22.25 122 125 3 0 3.60 0.44 22.25 22.5 125 128 3 0 3.55 0.43 22.5 22.75 128 131 3 0 3.40 0.42 22.75 23 131 134 3 0 3.55 0.44 23 23.25 134 137 3 0 3.75 0.45 23.25 23.5 137 140 3 0 3.25 0.41 23.5 23.75 140 142 3 0 3.65 0.38 23.75 24 142 145 3 0 3.60 0.40 24 24.25 145 148 3 0 3.55 0.40 24.25 24.5 148 151 3 0 3.60 0.43 24.5 24.75 151 154 3 0 3.90 0.64 24.75 25 154 157 3 0 4.00 0.71 25 25.25 157 160 3 0 3.95 0.77 25.25 25.5 160 163 3 0 4.05 0.96 25.5 25.75 163 165 3 0 4.00 0.88 25.75 26 165 168 3 0 4.20 0.92 26 26.25 168 171 3 0 4.00 0.87 26.25 26.5 171 174 3 0 4.00 0.85 26.5 26.75 174 177 3 0 4.10 0.78 26.75 27 177 180 2.5 0 3.40 0.81 27 27.25 180 183 3 0 4.00 0.86 27.25 27.5 183 186 2.5 0 3.45 0.85 27.5 27.75 186 188 3 0 3.70 0.90 27.75 28 188 191 3 0 3.60 0.97 28 28.25 191 194 3 1 4.25 1.08 28.25 28.5 194 197 3 0 4.05 1.13 28.5 28.75 197 200 3 0 3.85 0.85 28.75 29 200 203 3 0 4.30 0.71 29 29.25 203 206 3 0 4.45 0.66 29.25 29.5 206 209 3 0 4.25 0.56 29.5 29.75 209 212 3 0 4.25 0.62 29.75 30 212 214 3 0 4.55 0.73 30 30.25 214 217 3 0 4.55 0.80 30.25 30.5 217 220 3 0 4.50 0.77 30.5 30.75 220 223 3 0 4.35 0.77 30.75 31 223 226 3 0 4.35 0.93 31 31.25 226 229 3 0 4.10 0.63 31.25 31.5 229 232 3 0 4.40 1.02 31.5 31.75 232 235 3 0 4.30 0.69 31.75 32 235 238 3 0 4.10 0.63 32 32.25 238 241 3 0 4.10 0.52 32.25 32.5 241 244 3 0 4.05 0.44 32.5 32.75 244 246 3 0 4.20 0.38 32.75 33 246 249 3 0 3.60 0.40 33 33.25 249 252 3 0 3.15 0.50 33.25 33.5 252 255 3 0 3.80 0.56 33.5 33.75 255 258 3 0 2.70 0.55 33.75 34 258 261 3 0 3.20 0.56 34 34.25 261 264 3 0 5.30 0.51 34.25 34.5 264 267 3 0 3.90 0.52 34.5 34.75 267 270 3 0 4.25 0.58 34.75 35 270 273 3 0 4.15 0.57 35 35.25 273 276 3 0 4.30 0.53 35.25 35.5 276 279 3 0 4.40 0.63 35.5 35.75 279 282 3 0 4.45 0.62 35.75 36 282 284 3 0 4.50 0.57 36 36.25 284 287 3 0 4.20 0.54 36.25 36.5 287 290 3 0 4.50 0.61 36.5 36.75 290 293 3 0 4.30 0.55 36.75 37 293 296 3 0 4.25 0.54 37 37.25 296 299 3 0 4.20 0.50 37.25 37.5 299 302 3 0 3.85 0.44 37.5 37.75 302 305 3 0 4.30 0.55 37.75 38 305 308 3 0 4.15 0.51 38 38.25 308 311 3 0 4.40 0.52 38.25 38.5 311 314 3 0 4.40 0.59 38.5 38.75 314 317 2.5 0 3.75 0.62 38.75 39 317 320 3 0 4.65 0.71 39 39.25 320 323 3 0 4.50 0.74 39.25 39.5 323 326 3 0 4.45 0.72 39.5 39.75 326 329 2.5 0 3.90 0.69 39.75 40 329 332 3 0 4.85 0.73 40 40.25 332 335 3 0 4.75 0.73 40.25 40.5 335 338 3 0 4.85 0.66 40.5 40.75 338 341 3 0 4.60 0.54 40.75 41 341 344 3 0 4.65 0.58 41 41.25 344 347 3 0 4.50 0.56 41.25 41.5 347 350 3 0 4.50 0.63 41.5 41.75 350 353 3 0 4.55 0.66 41.75 42 353 356 3 0 4.00 0.57 42 42.25 356 359 3 0 4.70 0.62 42.25 42.5 359 362 3 0 4.45 0.58 42.5 42.75 362 365 3 0 4.60 0.55 42.75 43 365 368 3 0 3.95 0.45 43 43.25 368 371 3 0 4.10 0.46 43.25 43.5 371 374 3 0 4.30 0.48 43.5 43.75 374 377 3 0 4.65 0.53 43.75 44 377 380 3 0 4.35 0.54 44 44.25 380 383 3 0 4.65 0.56 44.25 44.5 383 386 3 0 4.65 0.52 44.5 44.75 386 389 3 0 4.70 0.51 44.75 45 389 392 3 0 4.45 0.55 45 45.25 392 395 3 0 4.25 0.50 45.25 45.5 395 398 3 0 4.45 0.54 45.5 45.75 398 401 3 0 4.10 0.58 45.75 46 401 404 3 0 4.85 0.69 46 46.25 404 407 3 0 4.70 0.75 46.25 46.5 407 410 3 0 5.05 0.76 46.5 46.75 410 413 3 0 4.60 0.83 46.75 47 413 416 3 0 4.95 0.83 47 47.25 416 420 3 0 4.90 0.83 47.25 47.5 420 423 3 0 4.50 0.68 47.5 47.75 423 426 3 0 4.55 0.67 47.75 48 426 429 3 0 4.75 0.68 48 48.25 429 432 3 0 3.90 0.51 48.25 48.5 432 435 3 0 3.85 0.43 48.5 48.75 435 438 3 0 3.95 0.46 48.75 49 438 441 3 0 4.55 0.54 49 49.25 441 444 3 0 4.70 0.57 49.25 49.5 444 447 3 0 4.25 0.53 49.5 49.75 447 450 3 0 3.90 0.51 49.75 50 450 454 3 0 4.50 0.57 50 50.25 454 457 3 0 4.30 0.75 50.25 50.5 457 460 3 0 5.00 0.70 50.5 50.75 460 463 3 0 4.00 0.69 50.75 51 463 466 3 0 4.40 0.67 51 51.25 466 469 3 0 4.30 0.70 51.25 51.5 469 472 3 0 4.55 0.75 51.5 51.75 472 475 3 0 3.90 0.67 51.75 52 475 479 3 0 4.15 0.78 52 52.25 479 482 3 0 5.05 0.88 52.25 52.5 482 485 3 0 4.40 0.95 52.5 52.75 485 488 3 0 5.00 1.18 52.75 53 488 491 3 0 4.10 1.14 53 53.25 491 494 3 0 4.90 1.24 53.25 53.5 494 498 3 0 4.20 1.23 53.5 53.75 498 501 3 0 5.20 1.14 53.75 54 501 504 3 0 4.45 1.00 54 54.25 504 507 3 0 4.80 0.76 54.25 54.5 507 510 3 0 4.30 0.73 54.5 54.75 510 513 3 0 4.60 0.77 54.75 55 513 517 3 0 5.20 0.69 55 55.25 517 520 3 0 5.70 0.70 55.25 55.5 520 523 3 0 4.95 0.58 55.5 55.75 523 526 3 0 5.05 0.62 55.75 56 526 529 3 0 4.80 0.53 56 56.25 529 533 3 0 4.65 0.52 56.25 56.5 533 536 3 0 4.25 0.49 56.5 56.75 536 539 3 0 4.00 0.45 56.75 57 539 542 3 0 4.60 0.51 57 57.25 542 546 3 0 4.75 0.54 57.25 57.5 546 549 3 0 4.60 0.56 57.5 57.75 549 552 3 0 4.40 0.58 57.75 58 552 555 3 0 5.30 0.57 58 58.25 555 559 3 0 4.55 0.65 58.25 58.5 559 562 3 0 4.35 0.62 58.5 58.75 562 565 3 0 4.40 0.54 58.75 59 565 568 3 0 4.25 0.50 59 59.25 568 572 3 0 3.85 0.60 59.25 59.5 572 575 3 0 3.60 0.44 59.5 59.75 575 578 3 0 4.15 0.55 59.75 60 578 581 3 0 4.80 0.64 60 60.25 581 585 3 0 4.70 0.64 60.25 60.5 585 588 3 0 4.80 0.63 60.5 60.75 588 591 3 0 4.50 0.59 60.75 61 591 595 3 0 4.40 0.55 61 61.25 595 598 3 0 4.45 0.53 61.25 61.5 598 601 3 0 4.20 0.49 61.5 61.75 601 605 3 0 4.35 0.53 61.75 62 605 608 3 0 4.40 0.52 62 62.25 608 611 3 0 4.45 0.51 62.25 62.5 611 615 3 1 4.20 0.53 62.5 62.75 615 618 3 0 4.60 -0.44 62.75 63 618 621 3 0 4.45 0.57 63 63.25 621 625 3 0 4.10 0.53 63.25 63.5 625 628 3 0 4.55 0.56 63.5 63.75 628 631 3 0 4.30 0.54 63.75 64 631 635 3 0 4.85 0.56 64 64.25 635 638 3 0 4.75 0.58 64.25 64.5 638 641 3 0 4.80 0.63 64.5 64.75 641 645 3 0 4.45 0.60 64.75 65 645 648 3 0 4.40 0.63 65 65.25 648 652 3 0 4.80 0.75 65.25 65.5 652 655 2.5 0 4.35 0.65 65.5 65.75 655 658 3 0 4.25 0.62 65.75 66 658 662 3 0 4.80 0.60 66 66.25 662 665 3 0 4.75 0.60 66.25 66.5 665 669 3 0 4.85 0.58 66.5 66.75 669 672 3 0 4.40 0.54 66.75 67 672 676 3 0 4.70 0.60 67 67.25 676 679 3 0 4.45 0.63 67.25 67.5 679 683 3 0 4.55 0.62 67.5 67.75 683 686 3 0 4.35 0.64 67.75 68 686 689 3 0 5.05 0.71 68 68.25 689 693 3 0 4.45 0.76 68.25 68.5 693 696 3 0 5.50 0.86 68.5 68.75 696 700 3 0 5.15 0.79 68.75 69 700 703 3 0 5.10 0.74 69 69.25 703 707 3 0 4.60 0.66 69.25 69.5 707 710 3 0 4.70 0.67 69.5 69.75 710 714 3 0 4.75 0.66 69.75 70 714 717 3 0 4.60 0.57 70 70.25 717 721 3 0 4.35 0.59 70.25 70.5 721 724 3 0 3.75 0.49 70.5 70.75 724 728 3 0 4.40 0.55 70.75 71 728 731 3 0 4.00 0.49 71 71.25 731 735 3 0 3.65 0.50 71.25 71.5 735 738 3 0 3.90 0.52 71.5 71.75 738 742 3 0 3.85 0.54 71.75 72 742 745 3 0 4.40 0.55 72 72.25 745 749 3 0 4.50 0.53 72.25 72.5 749 752 3 0 4.40 0.51 72.5 72.75 752 756 3 0 4.50 0.47 72.75 73 756 760 3 0 3.95 0.43 73 73.25 760 763 3 0 4.25 0.48 73.25 73.5 763 767 3 0 4.30 0.49 73.5 73.75 767 770 3 0 3.70 0.41 73.75 74 770 774 3 0 4.10 0.45 74 74.25 774 777 3 0 3.70 0.39 74.25 74.5 777 781 3 0 3.70 0.38 74.5 74.75 781 784 3 0 4.10 0.40 74.75 75 784 788 3 0 4.10 0.43 75 75.25 788 791 3 0 4.10 0.46 75.25 75.5 791 795 3 0 4.25 0.47 75.5 75.75 795 798 3 0 4.10 0.49 75.75 76 798 802 3 0 3.95 0.51 76 76.25 802 805 3 0 4.20 0.54 76.25 76.5 805 809 3 0 4.25 0.57 76.5 76.75 809 812 2.5 0 3.80 0.61 76.75 77 812 816 3 0 4.25 0.62 77 77.25 816 819 3 0 4.50 0.65 77.25 77.5 819 823 3 0 4.45 0.61 77.5 77.75 823 826 3 0 4.70 0.68 77.75 78 826 830 3 0 4.40 0.60 78 78.25 830 833 3 0 4.35 0.54 78.25 78.5 833 837 3 0 4.00 0.49 78.5 78.75 837 840 2.5 0 3.10 0.40 78.75 79 840 844 3 0 3.25 0.33 79 79.25 844 847 3 0 3.50 0.32 79.25 79.5 847 851 3 0 3.45 0.28 79.5 79.75 851 854 3 0 3.15 0.25 79.75 80 854 858 3 0 2.90 0.23 80 80.25 858 861 3 0 3.30 0.29 80.25 80.5 861 864 3 0 3.60 0.34 80.5 80.75 864 868 3 0 3.15 0.30 80.75 81 868 871 3 0 3.85 0.40 81 81.25 871 875 3 0 4.20 0.44 81.25 81.5 875 878 3 0 4.30 0.45 81.5 81.75 878 882 3 0 4.45 0.49 81.75 82 882 885 3 0 4.50 0.52 82 82.25 885 889 3 0 4.20 0.49 82.25 82.5 889 892 3 0 3.90 0.51 82.5 82.75 892 896 3 0 4.30 0.71 82.75 83 896 899 3 0 4.75 0.77 83 83.25 899 902 3 0 4.50 0.70 83.25 83.5 902 906 3 0 4.40 0.59 83.5 83.75 906 909 2.5 0 4.15 0.66 83.75 84 909 913 3 0 4.20 0.59 84 84.25 913 916 3 0 4.70 0.56 84.25 84.5 916 920 3 0 4.00 0.47 84.5 84.75 920 923 2.5 0 3.65 0.53 84.75 85 923 926 3 0 3.75 0.50 85 85.25 926 930 3 0 3.55 0.42 85.25 85.5 930 933 3 0 3.45 0.53 85.5 85.75 933 937 3 0 3.55 0.45 85.75 86 937 940 3 0 3.55 0.49 86 86.25 940 943 3 0 3.50 0.48 86.25 86.5 943 947 3 0 3.90 0.52 86.5 86.75 947 950 3 0 3.90 0.48 86.75 87 950 954 3 0 4.45 0.47 87 87.25 954 957 3 0 4.35 0.51 87.25 87.5 957 961 3 0 4.45 0.53 87.5 87.75 961 964 3 0 4.30 0.60 87.75 88 964 967 3 0 4.40 0.66 88 88.25 967 971 3 0 4.85 0.79 88.25 88.5 971 974 3 0 5.05 0.74 88.5 88.75 974 978 3 0 5.00 0.90 88.75 89 978 981 3 0 5.55 0.97 89 89.25 981 984 3 0 5.65 0.96 89.25 89.5 984 988 3 0 4.95 0.87 89.5 89.75 988 991 3 0 4.80 0.84 89.75 90 991 995 3 0 4.80 0.83 90 90.25 995 998 3 0 4.50 0.74 90.25 90.5 998 1001 3 0 4.55 0.72 90.5 90.75 1001 1005 3 0 4.55 0.66 90.75 91 1005 1008 3 0 3.95 0.56 91 91.25 1008 1012 3 0 4.00 0.60 91.25 91.5 1012 1015 3 0 4.40 0.65 91.5 91.75 1015 1018 3 0 4.45 0.66 91.75 92 1018 1022 3 0 4.60 0.70 92 92.25 1022 1025 3 0 4.40 0.72 92.25 92.5 1025 1028 3 0 4.15 0.68 92.5 92.75 1028 1032 3 0 4.40 0.82 92.75 93 1032 1035 3 0 4.35 0.84 93 93.25 1035 1039 3 0 4.35 0.88 93.25 93.5 1039 1042 3 0 4.40 0.84 93.5 93.75 1042 1045 2.5 0 2.90 0.70 93.75 94 1045 1049 3 0 4.05 0.72 94 94.25 1049 1052 3 0 4.40 0.72 94.25 94.5 1052 1056 3 0 3.65 0.57 94.5 94.75 1056 1059 3 0 3.70 0.48 94.75 95 1059 1062 3 0 3.45 0.48 95 95.25 1062 1066 3 0 3.80 0.52 95.25 95.5 1066 1069 3 0 3.85 0.52 95.5 95.75 1069 1072 3 0 3.65 0.52 95.75 96 1072 1076 3 0 3.80 0.57 96 96.25 1076 1079 3 0 3.50 0.60 96.25 96.5 1079 1083 3 0 3.45 0.62 96.5 96.75 1083 1086 3 0 3.20 0.68 96.75 97 1086 1089 3 0 3.35 0.70 97 97.25 1089 1093 3 0 3.45 0.69 97.25 97.5 1093 1096 3 0 3.50 0.69 97.5 97.75 1096 1099 3 0 3.85 0.64 97.75 98 1099 1103 3 0 4.00 0.58 98 98.25 1103 1106 3 0 4.35 0.57 98.25 98.5 1106 1110 3 0 3.70 0.52 98.5 98.75 1110 1113 3 0 4.30 0.52 98.75 99 1113 1116 2.5 0 3.50 0.54 99 99.25 1116 1120 3 0 4.10 0.55 99.25 99.5 1120 1123 3 0 4.15 0.54 99.5 99.75 1123 1126 3 0 3.95 0.51 99.75 100 1126 1130 3 0 3.90 0.53 100 100.25 1130 1133 3 0 3.95 0.52 100.25 100.5 1133 1137 3 0 4.10 0.50 100.5 100.75 1137 1140 3 0 3.90 0.51 100.75 101 1140 1143 3 0 3.75 0.48 101 101.25 1143 1147 3 0 4.15 0.51 101.25 101.5 1147 1150 3 0 3.65 0.48 101.5 101.75 1150 1153 3 0 3.75 0.50 101.75 102 1153 1157 3 0 3.75 0.48 102 102.25 1157 1160 3 0 3.95 0.47 102.25 102.5 1160 1163 3 0 3.95 0.48 102.5 102.75 1163 1167 2.5 0 3.10 0.54 102.75 103 1167 1170 2 0 2.45 0.57 103 103.25 1170 1174 3 0 4.05 0.62 103.25 103.5 1174 1177 2 0 2.70 0.65 103.5 103.75 1177 1180 2 0 2.50 0.68 103.75 104 1180 1184 3 0 3.25 0.59 5. Toolik Moisture data June-September mean temperature (deg. C) from NCEP reanalysis for AR grid cell, as in Fig. 3 Year_AD Precip_mm Evap_mm P-E_mm 1948 96.15 105.89 -9.74 1949 54.04 72.82 -18.78 1950 53.46 79.55 -26.08 1951 117.82 120.61 -2.79 1952 69.15 89.54 -20.39 1953 76.02 101.86 -25.84 1954 75.01 112.93 -37.92 1955 139.01 94.46 44.55 1956 46.49 88.5 -42.01 1957 93.77 109.63 -15.87 1958 52.74 79.4 -26.66 1959 65.88 100.58 -34.7 1960 23.7 72.23 -48.53 1961 71.55 104.61 -33.06 1962 83.57 113.27 -29.71 1963 95.7 124.96 -29.26 1964 27.44 76.64 -49.2 1965 48.3 76.12 -27.82 1966 112.47 105.28 7.19 1967 73.42 100.5 -27.08 1968 43.7 85.66 -41.96 1969 87.37 95.33 -7.95 1970 74.47 91.9 -17.43 1971 91.17 93.68 -2.5 1972 75.91 94.93 -19.03 1973 80.62 100.55 -19.93 1974 49.13 81.11 -31.97 1975 84.15 81.48 2.67 1976 35.82 63.42 -27.6 1977 54.53 66.63 -12.1 1978 31.22 60.39 -29.18 1979 70.15 101.32 -31.17 1980 92.17 110.04 -17.87 1981 43.76 86.07 -42.3 1982 85.4 92.54 -7.14 1983 35.24 81.74 -46.5 1984 89 102.98 -13.99 1985 81.06 86.24 -5.18 1986 30.75 79.02 -48.27 1987 70.08 107.16 -37.09 1988 76.84 92.57 -15.74 1989 76.41 116.68 -40.26 1990 63.28 90.3 -27.02 1991 49.96 90.07 -40.11 1992 70.47 86.33 -15.86 1993 144.21 127.59 16.62 1994 149.65 97.1 52.55 1995 57.6 86.87 -29.27 1996 95.99 109.77 -13.78 1997 81.3 102.52 -21.21 1998 115.77 134.34 -18.58 1999 113.5 109.88 3.62 2000 61.73 85.69 -23.96 2001 63.69 95.31 -31.62 2002 75.01 95.15 -20.14 2003 100.37 97.69 2.67 2004 94.36 111.26 -16.89 2005 50.64 94.99 -44.35 2006 58.08 85.31 -27.23 2007 22.48 79.78 -57.3 2008 71.67 104.91 -33.25 2009 50.61 69.43 -18.82 6. Toolik temperature data June-September mean precipication (mm) and moisture deficit (mm) from NCEP reanalysis for AR grid cell, as in Fig. 3 year_AD JJAS_temp_C 1948 6.34 1949 8.43 1950 9.38 1951 7.84 1952 6.74 1953 8.19 1954 7.83 1955 7.65 1956 7.14 1957 8.86 1958 9.75 1959 6.94 1960 6.8 1961 8 1962 8.5 1963 6.75 1964 8.46 1965 7.61 1966 8.05 1967 5.85 1968 8.52 1969 6.73 1970 5.44 1971 6.38 1972 8.19 1973 5.86 1974 6.46 1975 5.95 1976 7.93 1977 8.88 1978 7.65 1979 7.81 1980 5.55 1981 4.3 1982 7.2 1983 5.75 1984 6.22 1985 6.33 1986 6.82 1987 6.43 1988 7.15 1989 7.63 1990 7.15 1991 5.79 1992 5.75 1993 7.28 1994 7.1 1995 9.04 1996 5.47 1997 9.49 1998 8.92 1999 9.12 2000 6.66 2001 7.96 2002 7.61 2003 5.88 2004 9.83 2005 8.88 2006 8.36 2007 11.1 2008 7.98 2009 7.96 7. Sea Ice Extent year seaIceExtent_km2 1979 7485057 1980 7411958 1981 7143222 1982 7524538 1983 7550505 1984 7142083 1985 6984499 1986 7404748 1987 7407366 1988 7106068 1989 7157707 1990 6565539 1991 6778529 1992 7249156 1993 6462165 1994 6970839 1995 6309008 1996 7378221 1997 6604005 1998 6329814 1999 6444245 2000 6337658 2001 6459344 2002 6253603 2003 6204090 2004 6405226 2005 6003239 2006 5879079 2007 5094788 2008 5418859 2009 5536320 8. MODIS hotspot points for the AR Fire, from 15 July through 1 October, 2007, as in Fig. 2a. dayOfYear MODIS_points 196 0 197 2 198 0 199 2 200 5 201 5 202 4 203 1 204 7 205 0 206 0 207 0 208 5 209 0 210 0 211 0 212 0 213 0 214 0 215 0 216 0 217 0 218 0 219 0 220 0 221 0 222 0 223 0 224 0 225 4 226 0 227 0 228 0 229 0 230 0 231 0 232 0 233 8 234 3 235 8 236 9 237 4 238 0 239 11 240 14 241 20 242 14 243 3 244 0 245 1 246 6 247 10 248 6 249 0 250 34 251 72 252 52 253 111 254 25 255 34 256 190 257 24 258 13 259 0 260 2 261 29 262 23 263 8 264 0 265 17 266 8 267 31 268 24 269 0 270 4 271 4 272 2 273 1 274 0 275 0 9. Tundra Area Burned Annual area burned in Alaska, north of 68 degrees N latitude (km2), 1950-2009, as in Fig. 2b. year annual_area_burned_km2 1950 0 1951 0 1952 0 1953 0 1954 0 1955 0 1956 0 1957 0 1958 0 1959 0 1960 0 1961 0 1962 0 1963 0 1964 0 1965 0 1966 0 1967 0 1968 0 1969 0 1970 0 1971 0 1972 0 1973 0 1974 0 1975 0 1976 8 1977 34 1978 0 1979 0 1980 0 1981 0 1982 0 1983 0 1984 0 1985 8 1986 0 1987 0 1988 0 1989 0 1990 0 1991 0 1992 0 1993 401 1994 0 1995 0 1996 0 1997 0 1998 0 1999 0 2000 0 2001 0 2002 0 2003 2 2004 0 2005 0 2006 0 2007 1047 2008 0 2009 1 10. Alaska area burned Annual area burned in Alaskan tundra and predicted annual area burned based on GBM model, as in Fig. 4a. year obs_annual_area_burned_km2 predicted_annual_area_burned_km2 1950 0 304 1951 0 205 1952 0 129 1953 0 129 1954 1918 1663 1955 4 36 1956 650 129 1957 2848 1879 1958 0 290 1959 103 186 1960 153 36 1961 0 36 1962 12 56 1963 0 129 1964 0 186 1965 0 30 1966 0 204 1967 0 186 1968 19 230 1969 0 56 1970 359 204 1971 2202 1548 1972 502 348 1973 57 129 1974 198 348 1975 1 186 1976 12 230 1977 5963 5406 1978 0 331 1979 18 331 1980 0 186 1981 624 186 1982 1 197 1983 32 129 1984 123 129 1985 21 129 1986 54 205 1987 78 304 1988 926 361 1989 21 175 1990 348 274 1991 319 349 1992 3 186 1993 670 290 1994 32 34 1995 16 349 1996 17 186 1997 695 787 1998 0 191 1999 416 274 2000 55 30 2001 0 186 2002 1336 361 2003 179 129 2004 197 466 2005 989 787 2006 231 304 2007 1211 1077 2008 44 56 2009 145 331