# Last Chance Lake, East Greenland Holocene Chironomid Data and Inferred Temperature #----------------------------------------------------------------------- # 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/22091 # Description: # Online_Resource: https://www1.ncdc.noaa.gov/pub/data/paleo/insecta/chironomidae/northamerica/greenland/last-chance2017temp.txt # Description: # # Original_Source_URL: # Description: # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Insecta # # Dataset DOI: # # Parameter_Keywords: population abundance, reconstruction #-------------------- # Contribution_Date # Date: 2017-05-16 #-------------------- # File_Last_Modified_Date # Date: 2017-05-16 #-------------------- # Title # Study_Name: Last Chance Lake, East Greenland Holocene Chironomid Data and Inferred Temperature #-------------------- # Investigators # Investigators: Axford, Y.; Levy, L.B.; Kelly, M.A.; Francis, D.R.; Hall, B.L.; Langdon, P.G.; Lowell, T.V. #-------------------- # Description_Notes_and_Keywords # Description: Chironomid assemblage data and chironomid-inferred paleo-temperature from sediments collected in # Last Chance Lake, East Greenland, for the past 11,500 years. # Provided Keywords: Arctic, Holocene Thermal Maximum, Neoglacial, Greenland, Scoresby Sund, lake sediments, insects, chironomids, Chironomidae, midges, paleotemperatures #-------------------- # Publication # Authors: Yarrow Axford, Laura B. Levy, Meredith A. Kelly, Donna R. Francis, Brenda L. Hall, Peter G. Langdon and Thomas V. Lowell # Published_Date_or_Year: 2017-04-06 # Published_Title: Timing and magnitude of early to middle Holocene warming in East Greenland inferred from chironomids # Journal_Name: Boreas # Volume: # Edition: # Issue: # Pages: # Report_Number: # DOI: 10.1111/bor.12247 # Online_Resource: http://onlinelibrary.wiley.com/doi/10.1111/bor.12247/full # Full_Citation: # Abstract: Much of Greenland experienced summers warmer than present in parts of the early to middle Holocene, during a precession-driven positive anomaly in summer insolation. However, the magnitude of that warmth remains poorly known, and its timing and spatial pattern are uncertain. Here we describe the first quantitative Holocene palaeotemperature reconstruction from central East Greenland based upon insect (chironomid) assemblages preserved in lake sediments. We postulate that landscapes like our study site, characterized by minimal soil and vegetation development through the Holocene and thus little influenced by some important secondary gradients, are especially well suited to the use of chironomids to reconstruct Holocene temperatures. The inferred timing of warmth at our study site near Scoresby Sund agrees well with other nearby evidence, including glacial geological reconstructions and temperatures inferred from precipitation isotopes at Renland ice cap, supporting the use of chironomids to reconstruct temperatures at this site. We infer highest temperatures from c. 10 to 5.5 ka, followed by gradual cooling after 5.5 ka and progressively colder and less productive conditions after 3.5 ka. Models based upon two independent training sets yield similar inferred temperature trends, and suggest an average summer temperature anomaly from c. 10 to 5.5 ka of 3 to 4C relative to the preindustrial last millennium. The estimated overall rate of Neoglacial cooling averaged over the period from 5.5 to 0.5 ka was 0.6 to 0.8C per thousand years, more than twice the rate previously estimated for the Arctic as a whole. Given strong apparent spatial variability in Holocene climate around the Arctic, and the utility of palaeoclimate data for improving climate and ice-sheet models, it should be a priority to further quantify past temperature changes around the margins of the Greenland Ice Sheet, where few quantitative reconstructions exist and future warming will affect global sea level. #------------------ # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: ARC-1454734, ARC-0909270, ARC-0909285, ARC-0908081 #------------------ # Site_Information # Site_Name: Last Chance Lake # Location: North America>Greenland # Country: Greenland # Northernmost_Latitude: 70.90645 # Southernmost_Latitude: 70.90645 # Easternmost_Longitude: -25.56945 # Westernmost_Longitude: -25.55945 # Elevation: 660 m #------------------ # Data_Collection # Collection_Name: Yarrow2017temp # Earliest_Year: 11500 # Most_Recent_Year: 621 # Time_Unit: Cal. Year BP # Core_Length: # Notes: #------------------ # Chronology_Information # Chronology: # #---------------- # 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 years before present, , , , ,N, ## TanomFOR15 Temperature Anomaly, , , degrees C, July, Climate Reconstructions, , FOR15,N, ## TanomFRA06-TR Temperature Anomaly, , , degrees C, July, Climate Reconstructions, , FRA06-TR,N, ## TanomFRA06 Temperature Anomaly, , , degrees C, July, Climate Reconstructions, , FRA06,N, # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: # age_calBP TanomFOR15 TanomFRA06-TR TanomFRA06 621 0.000 0.000 0.000 1099 -0.658 -0.028 0.126 1748 -1.202 -0.172 -0.173 2475 1.156 0.031 0.405 3249 0.423 0.040 0.226 3633 -0.016 -0.087 0.261 4358 1.615 0.261 1.222 4685 2.414 1.362 2.944 5007 2.256 0.848 2.427 5340 3.299 2.221 4.345 5695 2.813 2.183 4.489 6083 3.328 4.027 6.863 6515 2.740 2.114 4.482 6989 2.674 0.731 2.132 7472 3.275 4.129 6.098 7946 3.658 4.115 6.422 8870 2.592 1.557 3.039 9231 3.803 3.953 6.619 10112 3.299 4.143 6.192 10719 -0.316 0.027 0.027 10979 1.097 0.401 0.821 11500 -0.618 0.092 0.092