# 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-kp2-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: KP-2 # Location: Russia # Northernmost_Latitude: 68.80 # Southernmost_Latitude: 68.80 # Easternmost_Longitude: 35.32 # Westernmost_Longitude: 35.32 # Elevation_m: 131 #-------------------- # Data_Collection # Collection_Name: KP2-Temp2012 # First_Year: 12090 # Last_Year: 0 # Time_Unit: cal yr BP # Core_Length_m: # Parameter_Keywords: reconstruction # Notes: Original publication Bjune et al. 2004 (doi:10.1080/03009480410001244) and 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_cm age_14C_BP1950 age_14C_1s_yr age_calib_BP1950 material_dated calib_curve # CURL-3340 28 1800 60 1730 macrofossils IntCal98 # CURL-3835 60 4630 50 5390 macrofossils IntCal98 # CURL-3341 82 5180 50 5940 macrofossils IntCal98 # CURL-3342 112 5720 50 6510 macrofossils IntCal98 # CURL-3829 180 8860 65 9970 macrofossils IntCal98 # CURL-3343 190 8890 55 10020 macrofossils IntCal98 # CURL-3830 220 9500 65 10640 macrofossils IntCal98 # CURL-3344 230 9410 70 10610 macrofossils 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 1 0 13.1082 1.09612 2 95 13.6713 1.09346 4 283 13.7513 1.1185 6 468 13.0485 1.08984 8 651 12.849 1.11048 10 831 12.8379 1.09112 12 1009 12.1595 1.09995 14 1184 12.7857 1.09156 16 1356 12.9024 1.09416 18 1526 13.623 1.08919 20 1694 12.7753 1.0904 22 1859 13.4678 1.08844 24 2021 13.1199 1.09603 26 2181 12.5978 1.08795 28 2339 12.9484 1.09736 30 2494 13.3377 1.08944 32 2648 13.066 1.09612 34 2798 13.9339 1.09446 36 2947 13.3373 1.09358 38 3093 13.4117 1.08921 40 3237 14.0527 1.0932 42 3379 13.6116 1.0909 44 3519 13.5542 1.09639 46 3657 13.0479 1.08885 48 3792 13.289 1.08925 50 3926 13.9025 1.08987 52 4057 14.0755 1.09077 54 4187 14.0755 1.09077 56 4315 14.2292 1.09056 58 4440 14.2158 1.09529 60 4564 13.9528 1.09268 62 4686 13.404 1.09289 64 4806 13.5454 1.0918 66 4924 13.4281 1.09283 68 5041 14.0069 1.08532 70 5156 14.0927 1.10233 72 5269 13.5599 1.08827 74 5380 13.6614 1.08793 76 5490 13.8212 1.08903 78 5598 14.1659 1.09567 82 5809 13.8077 1.09534 86 6014 13.3545 1.09621 90 6214 13.2682 1.09001 94 6407 14.019 1.08977 98 6595 14.0724 1.09151 102 6778 13.7834 1.09171 106 6957 14.3045 1.09055 110 7130 14.53 1.08842 114 7299 14.146 1.08955 118 7463 14.9113 1.09392 122 7624 14.5966 1.09021 126 7781 13.5217 1.08904 130 7934 13.9244 1.09388 132 8010 13.2183 1.0947 136 8158 13.0577 1.10102 140 8304 13.2736 1.10982 144 8447 13.0105 1.09377 148 8587 13.2777 1.10511 152 8726 12.7212 1.09709 156 8862 12.9703 1.10801 158 8930 12.3767 1.12682 160 8997 12.8873 1.11336 164 9130 13.1561 1.10947 168 9262 11.8831 1.11487 172 9393 11.441 1.13567 176 9523 11.2453 1.13615 180 9653 11.7301 1.13831 184 9782 11.6679 1.13451 188 9912 12.1132 1.13188 192 10041 11.6597 1.13659 196 10171 11.8617 1.17781 200 10302 12.1563 1.15843 204 10433 11.0698 1.16037 208 10566 10.9239 1.14894 212 10700 11.5699 1.14002 216 10836 10.321 1.1369 220 10974 10.0469 1.13542 224 11113 9.77937 1.14002 228 11256 10.1809 1.1262 230 11328 10.5062 1.1161 232 11400 10.9638 1.13521 234 11474 10.133 1.20715 236 11548 10.198 1.15869 238 11623 9.26978 1.23164 240 11698 10.6207 1.19835 242 11775 10.0778 1.3008 244 11852 8.56252 1.2362 246 11931 9.82864 1.23421 248 12010 10.4114 1.17614 250 12090 8.93722 1.30205