# Fennoscandia 7500Yr Pollen-TreeRing July Temperature Reconstructions #---------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #---------------------------------------------------- # Template Version 4.0 # Encoding: UTF-8 # NOTE: Please cite original publication, NOAA Landing Page URL, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, study title, NOAA Landing Page URL, and date accessed. # # Description/Documentation lines begin with # # Data lines have no # # # NOAA_Landing_Page: https://www.ncei.noaa.gov/access/paleo-search/study/13119 # Landing_Page_Description: NOAA Landing Page of this file's parent study, which includes all study metadata. # # Study_Level_JSON_Metadata: https://www.ncei.noaa.gov/pub/data/metadata/published/paleo/json/noaa-lake-13119.json # Study_Level_JSON_Description: JSON metadata of this data file's parent study, which includes all study metadata. # # Data_Type: Paleolimnology # # Dataset_DOI: 10.25921/e3j5-sv40 # # Science_Keywords: PAGES Arctic 2k, Air Temperature Reconstruction, PAGES 2k Network #-------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/paleolimnology/europe/fennoscandia2012-gammelheimenvatnet-noaa.txt # Data_Download_Description: NOAA Template File; Temperature Reconstruction from Pollen # #-------------------- # Contribution_Date # Date: 2012-06-30 #-------------------- # File_Last_Modified_Date # Date: 2024-06-06 #-------------------- # Title # Study_Name: Fennoscandia 7500Yr Pollen-TreeRing July Temperature Reconstructions #-------------------- # Investigators # Investigators: Helama, S.(https://orcid.org/0000-0002-9777-3354); Seppä, H.T.(https://orcid.org/0000-0003-2494-7955); Bjune, A.E.(https://orcid.org/0000-0002-4509-0148); Birks, H.J.B.(https://orcid.org/0000-0002-5891-9859) #-------------------- # Description_Notes_and_Keywords # Description: Pollen data and temperature reconstructions from 11 lakes in northern Fennoscandia, plus July pollen/tree-ring temperature reconstruction for the past 7500 years. # # Northern Fennoscandia: ~66°-70°N, ~14°-35°E #-------------------- # Publication # Authors: Helama, S., H. Seppä, A.E. Bjune, and H.J.B. Birks # Journal_Name: Journal of Paleolimnology # Published_Title: Fusing pollen-stratigraphic and dendroclimatic proxy data to reconstruct summer temperature variability during the past 7.5 ka in subarctic Fennoscandia # Published_Date_or_Year: 2012 # Volume: 48 # Pages: 275-286 # Issue: 1 # Report_Number: # DOI: 10.1007/s10933-012-9598-1 # Full_Citation: # Abstract: A new palaeoclimatic reconstruction of mid-summer (July) temperatures for the last 7.5 ka in northern Fennoscandia is presented. It is based on two botanical proxies: spectra of fossil pollen and tree rings of Scots pine logs recovered from lacustrine sediments in the Arctic tree-line region. A newly developed method of proxy fusion is used to integrate the proxy-specific reconstructions of past summer temperature variability based on the pollen-stratigraphic and dendroclimatic data. The rationale behind the method is that the two proxies are likely to be connected to climate variability in a timescale-dependent fashion and, accordingly, the new reconstruction makes use of the low- and high-frequencies from pollen-stratigraphic and tree-ring data, respectively. The most prominent features of the new reconstruction are: (1) the long-term decline of temperatures by 2.0°C over the past 7.5 ka, (2) the mid-Holocene warmth culminating between 5 and 4 ka as a deviation from the cooling trend, (3) the Little Ice Age cool phase between 0.7 and 0.1 ka, and (4) the subsequent warming during the past century. These periods are superimposed on year-to-year variations in climate as dated to calendar-year accuracy by dendrochronology. Within the modern period, the years 1934 and 1937 are among the warmest, and the years 1903 and 1910 are among the coldest summers in the context of the past 7.5 ka. On average, the reconstructed Holocene climate was approximately 0.85°C warmer than the twentieth century. #-------------------- # Authors: Helama, S., M. Macias Fauria, K. Mielikäinen, M. Timonen, and M. Eronen # Journal_Name: Geological Society of America Bulletin # Published_Title: Sub-Milankovitch solar forcing of past climates: Mid and late Holocene perspectives # Published_Date_or_Year: 2010 # Volume: 122 # Pages: 1981–1988 # Issue: 11-12 # Report_Number: # DOI: 10.1130/B30088.1 # Full_Citation: # Abstract: A comparison was performed of solar activity and terrestrial temperature records, both derived from tree rings (i.e., without dating uncertainties), with identification of detailed and highly quantified time- and timescale-dependent characteristics of solar forcing on climate through the current interglacial in the context of oceanic variability. The tree-ring–derived temperature record from high latitudes of Europe (Lapland) exhibits persistent annual-to-millennial–scale variations, with multidecadal to multicentennial periodicities reminiscent of the Sun's periodicities. At millennial scales, cool temperatures coincided with large-scale glacial maxima. Moreover, millennial and bimillennial modes of climate variability were correlative with variations in sunspot numbers on similar scales, with near-century and near-zero lags, respectively. Although they were subtle in amplitude, the sub-Milankovitch–scale changes in the reception of the Sun's energy could thus suffice to noticeably modulate interglacial climate variations. The relative significance of timescale-dependent, Sun-climate linkages has likely varied during the mid and late Holocene times, respectively. Thus, the warmer and cooler paleotemperatures during the Medieval Climate Anomaly and Little Ice Age were better explained by solar variations on a millennial rather than bimillennial scale. The observed variations may have occurred in association with internal climate amplification (likely, thermohaline circulation and El Niño–Southern Oscillation activity). The near-centennial delay in climate in responding to sunspots indicates that the Sun's influence on climate arising from the current episode of high sunspot numbers may not yet have manifested itself fully in climate trends. If neglected in climate models, this lag could cause an underestimation of twenty-first–century warming trends. #-------------------- # Funding_Agency # Funding_Agency_Name: # Grant: #-------------------- # Site_Information # Site_Name: Gammelheimenvatnet # Location: Norway # Northernmost_Latitude: 68.47 # Southernmost_Latitude: 68.47 # Easternmost_Longitude: 17.75 # Westernmost_Longitude: 17.75 # Elevation_m: 290 #-------------------- # Data_Collection # Collection_Name: Gammelheimenvatnet-Temp2012 # First_Year: 8968 # Last_Year: -42 # Time_Unit: cal yr BP # Core_Length_m: # Parameter_Keywords: reconstruction # Notes: Original publication Bjune et al. 2009 (doi:10.1007/s10933-008-9254-y) #-------------------- # Chronology_Information # Chronology: Radiocarbon # Chronology_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/templates/noaa-wds-paleo-14c-terms.csv # Chronology_Download_Description: Radiocarbon terms and definitions. # Chronology_Notes: Radiocarbon dates from Bjune et al. 2009 (doi:10.1007/s10933-008-9254-y) # Rejection_Rationale: # Reservoir_Method: nearly all the sites are located on acidic bedrock and there is no evidence for any significant "hard water" effects in the bulk-sediment ages. # Calibration_Method: CALIB4.3 (Stuiver and Reimer 1993) and the INTCAL98 calibration data set (Stuiver et al. 1998). # Age_Model_Method: linear regression # Missing_Values: NaN # Chronology_Table: # lab_code depth_end_cm depth_start_cm age_14C_BP1950 age_14C_1s_yr age_calib_BP1950 material_dated calib_curve # Tua-1555A 516.5 517 1035 70 940 gyttja IntCal98 # Tua-1556A 550.5 551 2360 65 2350 gyttja IntCal98 # Tua-1557A 606.5 607 3530 75 3798 gyttja IntCal98 # Tua-1558A 654.5 655 4420 55 5008 gyttja IntCal98 # Tua-1559A 704.5 705 5520 75 6298 gyttja IntCal98 # Tua-1560A 746.5 747 7390 125 8180 gyttja IntCal98 # Tua-1561A 752.5 753 7715 75 8451 gyttja IntCal98 # Tua-1562A 762 763 9135 110 10239 gyttja IntCal98 #-------------------- # Variables # PaST_Thesaurus_Download_Resource: https://www.ncei.noaa.gov/access/paleo-search/skos/past-thesaurus.rdf # PaST_Thesaurus_Download_Description: Paleoenvironmental Standard Terms (PaST) Thesaurus terms, definitions, and relationships in SKOS format. # # Data variables follow that are preceded by '##' in columns one and two. # Variables list, one per line, shortname-tab-var components: what, material, error, units, seasonality, data type, detail, method, C or N for Character or Numeric data) # ## depth_cm depth,,,centimeter,,climate reconstructions;pollen,,,N, ## age_calBP age,,,calendar year before present,,climate reconstructions;pollen,,,N, ## T-JULY temperature,,,degree Celsius,Jul,climate reconstructions;pollen,,,N, ## T-JULY-err temperature,,one standard error,degree Celsius,Jul,climate reconstructions;pollen,,,N,Bootstrap estimated SEP #-------------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: depth_cm age_calBP T-JULY T-JULY-err 488 -42 11.7418 1.09012 493 114 11.0772 1.10849 498 278 11.6512 1.09723 502 409 10.9951 1.09019 507 573 11.4775 1.08881 511 704 11.2398 1.10288 515 835 12.02 1.09707 519 966 12.8405 1.09734 523 1097 12.1282 1.10139 527 1229 13.0888 1.09143 531 1360 11.6449 1.11061 535 1491 12.8987 1.12069 539 1622 13.7379 1.10008 543 1753 12.6393 1.08866 547 1885 12.3442 1.0941 551 2016 12.4323 1.09924 555 2147 12.8062 1.11277 559 2278 11.5359 1.10527 563 2409 12.7459 1.09527 567 2540 13.0656 1.11258 571 2672 12.6015 1.1109 575 2803 12.0596 1.11399 579 2934 13.0509 1.12896 583 3065 12.7313 1.10149 587 3196 12.7114 1.13861 591 3327 12.6592 1.08935 595 3459 12.6883 1.09258 599 3590 13.4145 1.11484 603 3721 12.1003 1.11403 607 3852 11.4205 1.21354 611 3983 13.3374 1.13209 615 4115 13.4754 1.11403 619 4246 13.8459 1.15756 623 4377 13.8725 1.14173 627 4508 13.7387 1.10887 631 4639 13.3045 1.09906 635 4770 13.3184 1.1153 639 4902 14.0149 1.1608 643 5033 14.4867 1.15144 647 5164 13.7473 1.11022 651 5295 14.167 1.14403 655 5426 14.0142 1.13829 659 5557 13.9175 1.17406 663 5689 13.2128 1.11966 667 5820 13.5724 1.12514 671 5951 13.8124 1.11756 675 6082 13.6313 1.12264 679 6213 13.9951 1.1393 683 6345 13.8354 1.12331 687 6476 14.087 1.1337 691 6607 13.862 1.12632 695 6738 14.1434 1.13184 699 6869 13.7534 1.12461 705 7066 14.4197 1.17585 709 7197 14.1534 1.12909 713 7328 13.8675 1.11846 717 7460 13.8287 1.12471 721 7591 14.3133 1.17449 725 7722 14.053 1.133 729 7853 13.6331 1.10228 733 7984 13.6335 1.21363 737 8115 13.8571 1.11748 741 8247 13.8995 1.19027 743 8312 14.0022 1.16019 745 8378 13.7566 1.12798 747 8443 13.6923 1.10026 749 8509 11.4028 1.09394 751 8575 12.4224 1.12257 753 8640 11.9204 1.10751 755 8706 12.0425 1.11424 757 8771 12.5068 1.10808 759 8837 10.3819 1.21956 761 8903 12.0917 1.11643 763 8968 8.13944 1.41456