# North Iceland Holocene Chironomid-Inferred Temperatures #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #----------------------------------------------------------------------- # Template Version 3.0 # Encoding: UTF-8 # 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: https://www.ncdc.noaa.gov/paleo/study/29332 # Description: NOAA Landing Page # Online_Resource: https://www1.ncdc.noaa.gov/pub/data/paleo/insecta/chironomidae/europe/iceland/litla-vidarvatn2007cit.txt # Description: NOAA location of the template # # Original_Source_URL: # Description: # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Climate Reconstructions # # Dataset DOI: # # Parameter_Keywords: air temperature #-------------------- # Contribution_Date # Date: 2020-03-24 #-------------------- # File_Last_Modified_Date # Date: 2020-03-24 #-------------------- # Title # Study_Name: North Iceland Holocene Chironomid-Inferred Temperatures #-------------------- # Investigators # Investigators: Axford, Y.; Miller, G.H.; Geirsdottir, A.; Langdon, P.G. #-------------------- # Description_Notes_and_Keywords # Description: Chironomid-inferred temperatures for 3 north Iceland lakes for the past 11,100 years. #-------------------- # Publication # Authors: Yarrow Axford, Gifford H. Miller, Aslaug Geirsdottir, Peter G. Langdon # Published_Date_or_Year: 2007-12-01 # Published_Title: Holocene temperature history of northern Iceland inferred from subfossil midges # Journal_Name: Quaternary Science Reviews # Volume: 26 # Edition: # Issue: 25-28 # Pages: 3344-3358 # Report_Number: # DOI: 10.1016/j.quascirev.2007.09.003 # Online_Resource: https://www.sciencedirect.com/science/article/abs/pii/S0277379107002387 # Full_Citation: # Abstract: The Holocene temperature history of Iceland is not well known, despite Iceland's climatically strategic location at the intersection of major surface currents in the high-latitude North Atlantic. Existing terrestrial records reveal spatially heterogeneous changes in Iceland's glacier extent, vegetation cover, and climate over the Holocene, but these records are temporally discontinuous and mostly qualitative. This paper presents the first quantitative estimates of temperatures throughout the entire Holocene on Iceland. Mean July temperatures are inferred based upon subfossil midge (Chironomidae) assemblages from three coastal lakes in northern Iceland. Midge data from each of the three lakes indicate broadly similar temperature trends, and suggest that the North Icelandic coast experienced relatively cool early Holocene summers and gradual warming throughout the Holocene until after 3 ka. This contrasts with many sites on Iceland and around the high-latitude Northern Hemisphere that experienced an early to mid-Holocene "thermal maximum" in response to enhanced summer insolation forcing. Our results suggest a heightened temperature gradient across Iceland in the early Holocene, with suppressed terrestrial temperatures along the northern coastal fringe, possibly as a result of sea surface conditions on the North Iceland shelf. #------------------ # Funding_Agency # Funding_Agency_Name: National Science Foundation # Grant: ATM-0318479, ATM-0317766, DGE-9987607 #------------------ # Site_Information # Site_Name: Litla Vidarvatn # Location: Europe>Northern Europe>Iceland # Country: Iceland # Northernmost_Latitude: 66.24098 # Southernmost_Latitude: 66.24098 # Easternmost_Longitude: -15.8076 # Westernmost_Longitude: -15.8076 # Elevation: 142 #------------------ # Data_Collection # Collection_Name: LitlaVidarvatn2007CIT # Earliest_Year: 9900 # Most_Recent_Year: 1240 # Time_Unit: Cal. Year BP # Core_Length: # Notes: #------------------ # Chronology_Information # Chronology: # Table 2 # Radiocarbon Ages from North Iceland Lakes # Lab number*a Core name Depth (cm) Material d13C Fraction modern 14C age (14Cyr BP) Calibrated age (cal yr BP)*b # AA60639 04-TORF-01 27.5 Plant-macro -13.1 0.9553 +/- 0.0047 367 +/- 39 404 +/- 81 # NSRL-14520 04-TORF-01 120 Plant-macro -26.5 0.8158 +/- 0.0018 1635 +/- 20 1539 +/- 19 # NSRL-14765 04-TORF-01 180 Humic *c -19.3 0.7311 +/- 0.0014 2515 +/- 20 2618 +/- 101 # NSRL-14517 04-TORF-01 227.5 Humic *c -17.4 0.6320 +/- 0.0010 3685 +/- 15 4031 +/- 49 # NSRL-14519 04-TORF-01 337.5 Betula leaf -4.7 0.4349 +/- 0.0010 6690 +/- 20 7551 +/- 31 # NSRL-14766 04-TORF-01 369 Humic *c -18.5 0.3469 +/- 0.0006 8505 +/- 16 9513 +/- 14 # NSRL-14518 04-TORF-01 432 Humic *c -15.9 0.3221 +/- 0.0008 9100 +/- 25 10240 +/- 9 # AA60636 04-SVID-03 36.5 Plant-macro -28 0.9585 +/- 0.0041 341 +/- 34 389 +/- 70 # NOSAMS-54832 04-SVID-03 177.5 Plant-macro -19.7 0.7797 +/- 0.0123 2000 +/- 130 1975 +/- 342 # AA60637 04-SVID-03 346 Plant-macro -29.6 0.6355 +/- 0.0030 3642 +/- 38 3978 +/- 87 # NOSAMS-54402 04-SVID-03 477.5 Plant-macro -26.2 0.4867 +/- 0.0029 5780 +/- 50 6572 +/- 68 # NSRL-14521 04-SVID-03 584.5 Plant-macro -23.6 0.3701 +/- 0.0014 7985 +/- 35 8883 +/- 105 # AA60638 04-SVID-03 731.5 Plant-macro -25.2 0.3230 +/- 0.0040 9079 +/- 99 10277 +/- 126 # NSRL-14522 04-LVID-01 29.5 Plant-macro -12.4 0.8139 +/- 0.0019 1655 +/- 20 1548 +/- 20 # AA60635 04-LVID-01 68 Plant-macro -28.1 0.7808 +/- 0.0035 1988 +/- 36 1941 +/- 48 # NSRL-14523 04-LVID-01 180.5 Plant-macro -26.7 0.6682 +/- 0.0013 3240 +/- 20 3443 +/- 33 # AA60634 04-LVID-01 304 Plant-macro -27.6 0.4902 +/- 0.0026 5728 +/- 42 6533 +/- 84 # NSRL-14524 04-LVID-01 434.5 Plant-macro -12.5 0.3674 +/- 0.0010 8045 +/- 25 8912 +/- 102 # # *a Samples labeled AA were submitted to the Arizona Accelerator Mass Spectrometry Laboratory; samples labeled NSRL to the University of Colorado # INSTAAR Laboratory for AMS Radiocarbon Preparation and Research; samples labeled NOSAMS to the National Ocean Sciences AMS facility at the # Woods Hole Oceanographic Institution. # *b Each calibrated age is the midpoint +/- 1/2 the 1s range calculated using CALIB 5.0.2 (Stuiver et al., 2005). # *c Analysis of humic acids extracted from bulk sediment. #---------------- # Variables # # Data variables follow are preceded by "##" in columns one and two. # Data line variables format: one per line, shortname-tab-variable components (what, material, error, units, seasonality, data type,detail, method, C or N for Character or Numeric data, free text) # ## age_calBP age, , ,calendar year before present, ,climate reconstructions, , ,N, ## temperature air temperature,midge assemblage,,degree Celsius,Jul,paleolimnology; insect; climate reconstructions,,,N,Temps are inferred with Oliveridia removed from the training set and the fossil samples as described in Axford et al QSR 2007. Model RMSEP is 1.10 degrees. # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: # age_calBP temperature 1240 8.19 1511 8.73 1847 8.94 2256 9.84 2947 8.39 3741 8.26 4592 9.12 5426 9.20 6255 8.85 7093 9.21 7581 7.31 8036 8.79 8452 8.10 8973 7.72 9900 7.00