# GISP2 and WAIS Divide Ice Cores 60,000 Year Surface 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.ncdc.noaa.gov/paleo/study/34133 # Landing_Page_Description: # # Study_Level_JSON_Metadata: https://www.ncei.noaa.gov/pub/data/metadata/published/paleo/json/noaa-icecore-34133.json # Study_Level_JSON_Description: JSON metadata of this data file's parent study, which includes all study metadata. # # Data_Type: Ice Cores # # Dataset_DOI: 10.25921/w9tc-hy73 # # Science_Keywords: Last Glacial Maximum, Air Temperature Reconstruction #-------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/icecore/antarctica/wais2021temp.txt # Data_Download_Description: # # Supplemental_Download_Resource: # Supplemental_Description: # # Related_Online_Resource: # Related_Online_Description: # # Original_Source_URL: # Original_Source_Description: #-------------------- # Contribution_Date # Date: 2021-09-17 #-------------------- # File_Last_Modified_Date # Date: 2021-09-17 #-------------------- # Title # Study_Name: GISP2 and WAIS Divide Ice Cores 60,000 Year Surface Temperature Reconstructions #-------------------- # Investigators # Investigators: Buizert, C. #-------------------- # Description_Notes_and_Keywords # Description: Surface temperature reconstructions for the GISP2 (Greenland) and WAIS Divide (Antarctica) ice cores based on the gas age-ice age difference, for the past 60,000 years. # Provided Keywords: Ice cores, Last Glacial Maximum, Gas age-ice age difference #-------------------- # Publication # Authors: Buizert, Christo # Published_Date_or_Year: 2021 # Published_Title: The ice core gas age-ice age difference as a proxy for surface temperature # Journal_Name: Geophysical Research Letters # Volume: 48 # Edition: # Issue: 20 # Pages: e2021GL094241 # Report_Number: # DOI: 10.1029/2021GL094241 # Publication_Place: # Publisher: # ISBN: # Online_Resource: # Other_Reference_Details: # Full_Citation: # Abstract: Ice cores provide detailed records of past climate change. Water stable isotopes are the most commonly used ice core climate proxy, but their quantitative interpretation remains challenging. Here I argue that the gas age-ice age difference (Dage) is a powerful proxy for past surface temperature. An analytical framework is derived that directly links past temperature to firn properties that can be reliably reconstructed (Dage, lock-in depth). The framework is calibrated using both present-day spatial patterns and last glacial maximum temperatures reconstructed via borehole thermometry. The usefulness of the method is demonstrated using three case studies from Greenland and Antarctic ice cores. The calibration suggests that several firn densification models, with the possible exception of the Herron-Langway model, have insufficient sensitivity to accumulation rates. This low sensitivity, in combination with large amplitude temperature forcing, can explain historical difficulties of densification models in simulating ice age firn thickness in East Antarctica. #-------------------- # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: 1643394, 1702920, 2102944 #-------------------- # Site_Information # Site_Name: WAIS Divide # Location: Antarctica # Northernmost_Latitude: -79.47 # Southernmost_Latitude: -79.47 # Easternmost_Longitude: -112.09 # Westernmost_Longitude: -112.09 # Elevation_m: 1797 #-------------------- # Data_Collection # Collection_Name: Buizert2021WAIStemp # Earliest_Year: 64242 # Most_Recent_Year: 126 # Time_Unit: Cal. Year BP # Core_Length_m: # Parameter_Keywords: age control, reconstruction # Notes: #-------------------- # Chronology_Information # Chronology: # #-------------------- # Variables # # PaST_Thesaurus_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/PaST-thesaurus/SKOS/past-thesaurus-v1.0.rdf # PaST_Thesaurus_Download_Description: Paleoenvironmental Standard Terms (PaST) Thesaurus terms, definitions, and relationships in SKOS format. # # Variables format: Short_name what,material,error,units,seasonality,data_type,detail,method,data_format,additional_information # ## Ice_age ice age,,,calendar year before present,,ice cores,,,N,WD2014 chronology; ice age relative to 1950 ## Gas_age gas age,,,calendar year before present,,ice cores,,,N,WD2014 chronology; ice age relative to 1950 ## Mean_age age,,,calendar year before present,,ice cores;climate reconstructions,averaged,,N, mean age ## Delta_age age,,,year,,ice cores,differenced,,N,Gas age-ice age difference ## LID lock-in depth,,,meter,,ice cores,,,N, ## T_anom surface temperature,,,degrees Celsius,,ice cores;climate reconstructions,anomalized,,N, calculated from the gas age-ice age difference ## T_anom_unc surface temperature,,two standard deviations,degrees Celsius,,ice cores;climate reconstructions,anomalized,,N, calculated from the gas age-ice age difference # #-------------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: (Value used to flag missing data in the table below) # Ice_age Gas_age Mean_age Delta_age LID T_anom T_anom_unc 230 22 126 208.0 67.4 0.00 0.69 8326 8145 8236 181.0 67.3 1.42 0.85 11740 11517 11629 223.6 72.0 -1.38 3.15 12988 12736 12862 252.0 74.1 -2.87 3.31 14804 14524 14664 279.5 74.4 -3.95 2.45 23761 23285 23523 475.7 76.2 -9.53 1.47 28144 27738 27941 406.5 76.5 -7.99 1.82 29397 28900 29148 496.8 72.0 -9.39 1.98 31243 30706 30975 537.1 68.5 -9.67 1.55 32945 32427 32686 518.0 71.1 -9.69 1.50 34095 33662 33879 433.1 74.8 -8.41 1.34 35792 35412 35602 379.8 81.0 -7.89 1.23 37032 36561 36797 471.1 72.7 -8.96 1.52 38515 38140 38328 375.3 79.6 -7.58 1.37 40511 40079 40295 431.6 79.9 -9.03 1.31 41774 41383 41578 390.8 81.5 -8.24 1.22 43655 43272 43463 382.5 81.9 -8.07 1.20 44748 44298 44523 450.0 79.0 -9.33 1.81 47122 46769 46946 353.4 86.1 -7.77 1.21 49712 49196 49454 516.0 73.5 -9.98 1.50 54424 54139 54282 285.1 85.2 -5.51 0.94 55333 54915 55124 417.8 77.3 -8.36 1.25 56102 55712 55907 389.8 77.4 -7.68 1.29 58320 57963 58141 356.7 76.4 -6.67 1.25 58566 58185 58376 381.1 76.6 -7.35 1.28 59327 58993 59160 334.5 80.8 -6.58 1.24 59665 59361 59513 303.7 80.8 -5.62 1.35 64460 64024 64242 436.0 80.3 -9.18 1.33