# EPICA Dronning Maud Land, EPICA South Pole - CO2 Data for the Last Millennium #----------------------------------------------------------------------- # 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/2488 # 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-icecore-2488.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/e57w-m804 # # Science_Keywords: #-------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/icecore/antarctica/maud/sp-co2-2005-noaa.txt # Data_Download_Description: NOAA Template File; Atmospheric Carbon Dioxide Data # #-------------------- # Contribution_Date # Date: 2005-07-01 #-------------------- # File_Last_Modified_Date # Date: 2022-07-20 #-------------------- # Title # Study_Name: EPICA Dronning Maud Land, EPICA South Pole - CO2 Data for the Last Millennium #-------------------- # Investigators # Investigators: Siegenthaler, U.; Monnin, E.; Kawamura, K.; Spahni, R.; Schwander, J.; Stauffer, B.; Stocker, T.F.; Barnola, J.M.; Fischer, H. #-------------------- # Description_Notes_and_Keywords # Description: We measured samples covering the time period from 950 to 1900 yr A.D. on 71 and 14 depth intervals of the DML and the South Pole ice core, respectively. At each depth interval of 60-100 mm, six samples were measured. The DML and South Pole data are corrected for gravitational separation of gases in the firn column based on the barometric formula to get closer to the true atmospheric value. For DML, a tentative timescale was used by adjusting the DML timescale to Dome C by comparing the records of electrical conductivity of both cores. The difference of gas age/ice age (D age) was assumed as 825 yrs. For the South Pole record, a new timescale was calculated, because an event recorded with the electrical conductivity method (ECM) attributed to a volcanic eruption in 1259 yr A.D. [Langway et al., 1988] indicates that the timescale used in Siegenthaler et al. [1988] is too young at this depth. This results in a lower average accumulation rate of 76.2 kg m-2yr-1 compared to the previously used value of 84 kg m-2yr-1. On average, the South Pole scale was about 200 yrs too young over the last millennium. #-------------------- # Publication # Authors: Siegenthaler, U., E. Monnin, K. Kawamura, R. Spahni, J. Schwander, B. Stauffer, T.F. Stocker, J.-M. Barnola, H. Fischer # Published_Date_or_Year: 2005-02-01 # Published_Title: Supporting evidence from the EPICA Dronning Maud Land ice core for atmospheric CO2 changes during the past millennium # Journal_Name: Tellus # Volume: 57B # Edition: # Issue: 1 # Pages: 51-57 # Report_Number: # DOI: 10.1111/j.1600-0889.2005.00131.x # Publication_Place: # Publisher: # ISBN: # Online_Resource: # Other_Reference_Details: # Full_Citation: # Abstract: The most direct method of investigating past variations of the atmospheric CO2 concentration before 1958, when continuous direct atmospheric CO2 measurements started, is the analysis of air extracted from suitable ice cores. Here we present a new detailed CO2 record from the Dronning Maud Land (DML) ice core, drilled in the framework of the European Project for Ice Coring in Antarctica (EPICA) and some new measurements on a previously drilled ice core from the South Pole. The DML CO2 record shows an increase from about 278 to 282 parts per million by volume (ppmv) between AD 1000 and AD 1200 and a fairly continuous decrease to a mean value of about 277 ppmv around AD 1700. While the new South Pole measurements agree well with DML at the minimum at AD 1700 they are on average about 2 ppmv lower during the period AD 1000–1500. Published measurements from the coastal high-accumulation site Law Dome are considered as very reliable because of the reproducibility of the measurements, high temporal resolution and an accurate time scale. Other Antarctic ice cores could not, or only partly, reproduce the pre-industrial measurements from Law Dome. A comparison of the trends of DML and Law Dome shows a general agreement. However we should be able to rule out co-variations caused by the same artefact. Two possible effects are discussed, first production of CO2 by chemical reactions and second diffusion of dissolved air through the ice matrix into the bubbles. While the first effect cannot be totally excluded, comparison of the Law Dome and DML record shows that dissolved air diffusing to bubbles cannot be responsible for the pre-industrial variation. Therefore, the new record is not a proof of the Law Dome results but the first very strong support from an ice core of the Antarctic plateau. #-------------------- # Funding_Agency # Funding_Agency_Name: European Commission # Grant: #-------------------- # Funding_Agency # Funding_Agency_Name: Swiss National Science Foundation # Grant: #-------------------- # Funding_Agency # Funding_Agency_Name: University of Bern # Grant: #-------------------- # Funding_Agency # Funding_Agency_Name: Swiss Federal Office of Energy # Grant: #-------------------- # Site_Information # Site_Name: EPICA South Pole # Location: Antarctica # Northernmost_Latitude: -90 # Southernmost_Latitude: -90 # Easternmost_Longitude: 0 # Westernmost_Longitude: 0 # Elevation_m: 2835 #-------------------- # Data_Collection # Collection_Name: EPICA South Pole Core 1 # Earliest_Year: 956 # Most_Recent_Year: 1737 # Time_Unit: CE # Core_Length_m: 192 # Parameter_Keywords: atmospheric gas # 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 # ## depth_m depth,,,meter,,ice cores;climate forcing,,,N, ## gas_ageBP gas age,,,calendar year before present,,ice cores;climate forcing,,,N, ## gas_ageCE gas age,,,year Common Era,,ice cores;climate forcing,,,N, ## CO2_mean carbon dioxide,bulk atmosphere,,parts per million,,ice cores;climate forcing,averaged,mechanical dry extraction;laser spectroscopy,N,mean value of 6 neighboring samples ## CO2_corr carbon dioxide,bulk atmosphere,,parts per million,,ice cores;climate forcing,corrected,mechanical dry extraction;laser spectroscopy,N,corrected for gravitational separation of gases in the firn column ## CO2_1s carbon dioxide,bulk atmosphere,one standard deviation,parts per million,,ice cores;climate forcing,,mechanical dry extraction;laser spectroscopy,N,one sigma of the mean value # #-------------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: depth_m gas_ageBP gas_ageCE CO2_mean CO2_corr CO2_1s 192.40 993.3 956.7 278.98 276.43 0.77 173.46 751.1 1198.9 281.51 278.94 0.56 171.42 725.3 1224.7 281.63 279.06 0.56 164.33 635.8 1314.2 281.26 278.69 0.82 161.09 595.1 1354.9 281.86 279.29 1.79 159.90 580.2 1369.8 283.30 280.71 0.90 153.92 505.5 1444.5 281.00 278.43 0.92 153.64 502.0 1448.0 280.66 278.09 0.90 143.70 379.3 1570.7 280.50 277.94 0.43 143.26 374.0 1576.0 280.18 277.62 0.35 138.72 318.6 1631.4 280.08 277.52 1.20 132.72 246.1 1703.9 278.55 276.01 1.32 132.06 238.2 1711.8 278.63 276.09 1.09 129.95 212.9 1737.1 279.95 277.39 0.77