# Abrupt Holocene climate transitions in the northern North Atlantic region recorded by synchronized lacustrine records in Iceland #----------------------------------------------------------------------- # World Data Center for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. # If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. # # # Online_Resource: http://hurricane.ncdc.noaa.gov/pls/paleox/f?p=519:1:::::P1_STUDY_ID:16279 # Online_Resource: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/paleolimnology/europe/iceland/hvt-geirsdottir-2013-raw-d13c.txt # # Original_Source_URL: # # Description/Documentation lines begin with # # Data lines have no # # # Archive: paleolimnology #-------------------- # Contribution_Date # Date: 2014-02-25 #-------------------- # Title # Study_Name: Abrupt Holocene climate transitions in the northern North Atlantic region recorded by synchronized lacustrine records in Iceland #-------------------- # Investigators # Investigators: Geirsdóttir,A.;Miller.G.H.;Larsen,D.J.;Ólafsdóttir,S. #-------------------- # Description_Notes_and_Keywords # Description: Keywords - Iceland, Lake sediment, Holocene paleoclimate, Abrupt climate transitions, 8.2 Event, Holocene Thermal Maximum, Neoglaciation, Medieval warm period, Little Ice Age, Geochemistry. #-------------------- # Publication # Authors: Geirsdóttir Á., G.H. Miller, D.J. Larsen, S. Ólafsdóttir # Published_Date_or_Year: 2013 # Published_Title: Abrupt Holocene climate transitions in the northern North Atlantic region recorded by synchronized lacustrine records in Iceland # Journal_Name: Quaternary Science Reviews # Volume: 70 # Edition: # Issue: # Pages: 48-62 # DOI: http://dx.doi.org/10.1016/j.quascirev.2013.03.010 # Online_Resource: # Full_Citation: # Abstract: Two high-sediment-accumulation-rate Icelandic lakes, the glacial lake Hvítárvatn and the non-glacial lake Haukadalsvatn, contain numerous tephra layers of known age, which together with highresolution paleomagnetic secular variations allow synchronization with a well-dated marine core from the shelf north of Iceland. A composite standardized climate record from the two lakes provides a single time series that efficiently integrates multi-proxy data that reflect the evolution of summer temperatures through the Holocene. The first-order trends in biogenic silica (BSi), d13C, and C:N rise relatively abruptly following deglaciation, reaching maximum values shortly after 8 ka following a complex minimum between 8.7 and 8.0 ka. The Holocene Thermal Maximum (HTM) in the lakes is marked by all proxies, with a sharp transition out of the 8 ka cold event into peak summer warmth by 7.9 ka, and continuing warm with some fluctuations until 5.5 ka. Decreasing summer insolation after the HTM is reflected by incremental cooling, initially w5.5 ka, with subsequent cold perturbations recorded by all proxies 4.3 to 4.0 ka and 3.1 to 2.8 ka. The strongest disturbance occurred after 2 ka with initial summer cooling occurring between 1.4 and 1.0 ka, followed by a more severe drop in summer temperatures after 0.7 ka culminating between 0.5 and 0.2 ka. Following each late Holocene cold departure, BSi re-equilibrated at a lower value independent of the sediment accumulation rate. Some of the abrupt shifts may be related to Icelandic volcanism influencing catchment stability, but the lack of a full recovery to pre-existing values after the perturbation suggests increased periglacial activity, decreased vegetation cover, and glacier growth in the highlands of Iceland. The similarity in timing, direction and magnitude of our multi-proxy records from glacial and non-glacial lakes, and from the adjacent marine shelf, suggests that our composite record reflects large-scale shifts in ocean/atmosphere circulation throughout the northern North Atlantic. #------------------ # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: OPP-0138010 #------------------ # Funding_Agency # Funding_Agency_Name: Icelandic Centre of Research, RANNIS # Grant: #040233021, #0070272011, and #100233021 #------------------ # Funding_Agency # Funding_Agency_Name: NSF-ARC # Grant: 0714074 #------------------ # Site_Information # Site_Name: Lake Hvítárvatn # Location: Europe, Iceland, northern North Atlantic region # Country: Iceland # Northernmost_Latitude: 64.613723 # Southernmost_Latitude: 64.613723 # Easternmost_Longitude: -19.843769 # Westernmost_Longitude: -19.843769 # Elevation: 38.33m #------------------ # Data_Collection # Collection_Name: HVT Raw C:N # Earliest_Year: 9158 # Most_Recent_Year: -6 # Time_Unit: cal yr BP # Core_Length: # Notes: Raw data against age for Carbon/Nitrogen. #------------------ # Chronology: # # # # # # # # #---------------- # Variables # # Data variables follow are preceded by "##" in columns one and two. # Data line variables format: Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # ##age_calBP Age,,,calendar years before present,,,,,N ##C:N Carbon/Nitrogen,sediment,,ratio,,paleolimnology,,,N # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: # age_calBP C:N -6 11.1 -1 11.52 3 13.4 8 11.62 12 11.61 15 11.16 19 10 22 10.78 25 9.59 29 12.42 32 12.06 33 13.77 39 12.75 42 10.04 44 11.46 47 12.27 50 12.54 53 12.59 56 10.04 59 12.69 63 11.59 66 9.88 70 17.79 76 10.78 80 13.13 87 13.41 96 12.51 105 13.81 107 12.52 113 12.62 115 12.18 123 12.38 129 12.25 132 11.8 133 12.55 137 12.99 144 12.64 153 12.78 160 11.66 169 12.08 177 11.95 209 11.21 221 11.49 236 11.61 254 11.78 271 11.64 293 12.7 318 11.59 341 12.77 363 11.22 385 11.67 405 11.6 425 11.39 444 10.76 462 11.1 478 10.13 500 9.88 517 11.21 533 12.43 551 10.54 571 10.41 591 10.53 612 11.01 635 10.62 652 11.03 655 7.71 663 8.85 668 9.06 673 7.29 679 9.66 684 8.26 690 8.55 695 9.03 698 8.55 701 9.71 707 10.66 712 9.21 718 7.73 724 7.57 730 9.53 736 8.79 743 10.1 749 9.55 755 9.46 762 9.67 768 9.25 775 7.34 781 8.26 788 7.46 795 7.12 802 7.96 809 8.19 818 8.85 827 7.58 836 8.3 844 7.43 854 9.33 862 8.02 872 10.12 882 8.63 885 9.42 889 10.03 893 7.64 895 11.07 899 9.85 899 7.33 909 8.46 916 10.01 928 9.7 935 7.58 947 7.86 956 8.47 966 8.81 975 8.64 985 8.73 994 7.6 1003 8.99 1021 5.96 1021 7.18 1038 8.14 1044 7.23 1055 7.92 1060 7.55 1071 8.39 1078 6.91 1086 8.27 1092 7.94 1099 8.86 1104 8.27 1111 10.11 1115 9.41 1121 11.01 1148 9.91 1161 7.84 1168 9.82 1178 10.87 1186 7.53 1198 9.16 1211 8.01 1221 9.74 1235 7.56 1237 11.91 1243 10.18 1250 8.22 1257 8.05 1264 8.6 1273 8.73 1282 10.46 1290 7.93 1299 9.7 1310 8.53 1317 9.81 1327 9.95 1335 10.13 1347 9.95 1353 9.87 1360 10.02 1373 9.28 1389 10.58 1399 11.05 1407 11.88 1418 11.92 1425 6.96 1436 8.76 1444 8.93 1453 7.04 1462 7.88 1471 7.81 1481 7 1492 5.61 1499 5.46 1511 4.72 1518 7.5 1529 4.99 1537 6.91 1548 5.92 1556 8.22 1574 7.38 1586 6.99 1593 7.68 1604 6.79 1612 9.25 1623 8.15 1631 6.07 1642 7.7 1650 6.27 1661 8.09 1669 7.27 1695 5.92 1706 7.12 1718 4.04 1729 5.62 1740 6.24 1751 7.11 1763 8.47 1774 7.91 1779 6.19 1788 6.92 1798 5.82 1808 6.75 1816 5.69 1827 6.82 1835 6.71 1846 6.78 1853 5.69 1865 7.34 1872 6.18 1883 6.09 1890 5.56 1900 7.27 1909 7.04 1920 8.28 1927 6.93 1937 7.34 1946 5.83 1957 7.06 1964 6.11 1977 6.32 1982 5.99 1993 6.03 2000 7.54 2011 5.82 2019 8.26 2031 6.87 2037 5.84 2048 6.45 2055 9.05 2064 6.06 2073 5.46 2080 5.17 2091 7.85 2109 6.33 2119 9.45 2127 8.64 2136 5.08 2145 5.26 2155 6.12 2162 7.77 2173 5.55 2180 5.47 2191 6.09 2198 6.92 2209 6.84 2216 8.29 2226 9.51 2233 6.33 2244 5.26 2251 5.77 2260 5.87 2269 5.39 2290 8.9 2304 6.13 2315 5.15 2322 4.45 2329 4.74 2340 4.26 2347 5.24 2357 4.41 2364 4.87 2375 4.68 2382 6.29 2393 6.94 2400 6.56 2410 4.74 2418 5.05 2428 5.4 2435 7.63 2446 5.79 2453 5.81 2464 6.11 2471 5.39 2482 5.33 2489 5.21 2499 4.55 2506 6.41 2517 5.65 2524 5.26 2535 6.31 2542 5.66 2553 5.44 2571 4.71 2578 5.69 2589 5.23 2596 5.73 2607 5.54 2614 5.45 2624 4.38 2632 5.7 2642 5.53 2649 6.02 2660 5.34 2667 5.55 2678 5.53 2685 6.09 2696 5.62 2703 5.99 2713 5.8 2720 5.78 2731 6.38 2738 6.04 2749 6.39 2756 5.91 2757 7.22 2764 7.58 2771 6.76 2778 7.65 2785 7.36 2792 7.68 2799 8.37 2806 7.45 2813 7.22 2820 8.3 2826 7.13 2833 7.36 2840 7.16 2846 8.51 2853 7.76 2856 7.77 2863 8.34 2873 7.36 2879 7.63 2889 6.95 2895 8.93 2905 8.02 2911 9.2 2920 8.31 2926 9.06 2935 8.97 2941 10.29 2950 11.22 2953 9.83 2957 11.36 2960 10.32 2964 10.22 2967 10.44 2971 11.09 2974 10.48 2978 9.18 2980 9.14 2984 7.95 2987 7.51 2991 5.5 3026 6.49 3034 5.75 3043 6.76 3055 5.33 3075 6.39 3094 6.15 3113 5.82 3132 5.73 3150 6.45 3168 5.5 3187 6.18 3205 5.55 3223 6.69 3242 5.58 3260 6.32 3279 4.87 3297 5.71 3316 5.33 3335 6.07 3353 5.71 3372 6.35 3391 6.08 3410 7.18 3428 5.8 3447 7.06 3465 6.43 3484 7.08 3502 6.4 3513 7.1 3552 6.77 3572 5.95 3586 7.21 3620 7.79 3633 6.49 3646 6.88 3658 6.22 3671 6.11 3684 6.38 3696 6.69 3709 5.89 3721 6.22 3733 6.16 3745 5.57 3757 6.47 3769 6.43 3781 6.2 3793 6.9 3805 6.34 3817 6.18 3829 6.25 3841 6.37 3853 6.1 3866 6.82 3878 6.47 3891 7.27 3903 6.08 3916 6.31 3929 6.71 3942 6.49 3956 6.72 3969 6.1 3983 6.41 3997 6.27 4011 6.4 4025 6.99 4039 6.72 4053 6.37 4068 6.8 4082 7.26 4096 7.11 4110 6.79 4124 6.95 4138 7.25 4151 7.23 4164 7.42 4176 7.24 4188 8.14 4199 7.97 4209 7.91 4217 8.66 4225 7.97 4231 7.52 4235 6.53 4252 6.53 4269 6.29 4286 6.3 4301 5.7 4316 5.94 4330 6.11 4344 6.23 4358 5.74 4371 6.07 4383 5.81 4395 5.87 4407 5.73 4418 5.81 4429 5.69 4440 5.81 4450 5.58 4460 5.85 4470 5.64 4480 4.9 4490 5.73 4499 5.78 4509 5.62 4518 5.28 4527 5.98 4537 5.62 4546 6.15 4555 5.62 4564 5.41 4574 5.77 4583 5.56 4592 5.54 4602 5.51 4611 5.6 4621 6.17 4631 5.87 4641 5.96 4651 6.06 4662 5.52 4672 5.78 4683 5.77 4694 6.06 4706 5.95 4717 5.81 4729 6.15 4741 5.84 4753 5.81 4766 5.85 4778 6.25 4791 5.79 4805 6.06 4818 5.81 4832 5.88 4846 6.45 4861 6.61 4875 6.47 4890 6.35 4905 6.04 4921 6.06 4937 6.3 4953 6.56 4969 5.92 4986 5.95 5002 5.77 5020 6.11 5037 5.84 5054 5.98 5072 5.47 5090 5.94 5108 5.42 5127 5.52 5145 5.6 5164 6.24 5183 5.48 5202 5.46 5221 5.81 5241 6.02 5260 5.63 5280 5.72 5300 5.87 5320 5.78 5340 5.53 5360 5.61 5380 5.84 5400 6.36 5421 6.26 5441 5.63 5461 5.86 5482 5.56 5502 5.71 5523 8.28 5543 5.56 5564 6.15 5584 5.01 5605 5.07 5625 4.89 5645 4.7 5666 5.05 5686 5.09 5706 5.54 5726 5.84 5746 5.69 5767 5.62 5787 5.47 5807 5.22 5827 5.58 5866 5.87 5886 6.42 5906 5.58 5926 6.03 5946 5.93 5965 5.54 5985 5.62 6005 6.71 6025 6.22 6045 6.26 6065 6.43 6085 5.78 6105 5.97 6126 6.16 6146 6.58 6167 5.9 6188 5.98 6210 5.68 6232 6.19 6254 6.02 6276 6.56 6299 6.18 6322 6.59 6346 7.08 6371 7.06 6396 7.52 6422 9.28 6449 7.54 6534 6.74 6565 6.47 6596 6.02 6629 5.45 6663 5.19 6699 5.12 6736 5.19 6775 5.7 6815 5.7 6857 5.32 6901 5.8 6947 5.98 6995 5.51 7045 5.45 7098 5.85 7212 6.38 7272 6.14 7336 5.88 7403 6.28 7473 5.91 7546 5.84 7623 5.69 7704 5.67 7789 5.33 7878 5.55 7934 7.19 7943 5 7952 5.94 7962 5.75 7972 5.82 7983 6.67 7993 9.84 8004 6.1 8015 6.11 8025 5.75 8036 6.07 8047 6.75 8057 5.89 8067 6.12 8077 6.55 8086 7.01 8095 6.52 8104 6.2 8113 6.5 8121 7.19 8128 6.56 8136 7.85 8142 7.1 8149 10.17 8155 6.64 8161 11.78 8166 6.63 8171 6.71 8175 7.28 8179 7.84 8183 7.57 8187 8.49 8190 7.98 8193 8.24 8195 8.44 8198 11.77 8200 9.11 8202 12.29 8203 8.38 8205 8.05 8206 13.68 8208 9.31 8209 7.35 8210 7.88 8211 10.25 8213 9.47 8214 10 8215 10.14 8216 11.75 8218 10.55 8219 10.9 8221 12.46 8223 12.24 8225 11.81 8227 12.15 8229 11.58 8232 10.81 8235 10.15 8238 10.19 8241 7.47 8245 8.69 8249 7.61 8253 7.87 8258 8.38 8263 7.75 8268 7.57 8274 7.57 8280 7.87 8286 7.55 8293 7.88 8300 8.32 8307 7.66 8315 8.24 8323 7.81 8332 8.77 8341 8.69 8350 8.1 8360 8.32 8370 10.12 8391 9.06 8402 8.1 8413 8.8 8437 9.45 8449 9.59 8462 10.77 8474 9.3 8487 8.71 8501 8.26 8514 8.61 8528 9.19 8542 10.91 8556 9.54 8570 8.2 8585 7.91 8599 8.05 8614 8.41 8629 9.52 8660 9.12 8675 8.95 8691 8.46 8706 8.25 8722 8.19 8738 9.05 8755 10.7 8771 10.93 8788 12 8805 8.57 8822 8.29 8839 8.3 8857 8.49 8875 8.45 8893 8.29 9012 13.33 9035 12.2 9057 15.11 9081 14.46 9106 9.17 9131 9.01 9158 9.54