# Bunker Cave, Germany 11,000 Year Stalagmite Stable Isotope and Mg/Ca Data #---------------------------------------------------- # 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/20589 # 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-cave-20589.json # Study_Level_JSON_Description: JSON metadata of this data file's parent study, which includes all study metadata. # # Data_Type: Speleothems # # Dataset_DOI: 10.25921/s829-3m55 # # Science_Keywords: #-------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/speleothem/europe/germany/bunker2012bu6-noaa.txt # Data_Download_Description: NOAA Template File; Bunker Cave Stalagmite Bu6 Stable Isotope and Mg/Ca Data # #-------------------- # Contribution_Date # Date: 2016-10-04 #-------------------- # File_Last_Modified_Date # Date: 2025-03-20 #-------------------- # Title # Study_Name: Bunker Cave, Germany 11,000 Year Stalagmite Stable Isotope and Mg/Ca Data #-------------------- # Investigators # Investigators: Fohlmeister, J.; Schröder-Ritzrau, A.; Scholz, D.(https://orcid.org/0000-0002-0055-8915); Spötl, C.(https://orcid.org/0000-0001-7167-4940); Riechelmann, D.F.C.; Mudelsee, M.; Wackerbarth, A.; Gerdes, A.; Riechelmann, S.; Immenhauser, A.(https://orcid.org/0000-0001-9494-2450); Richter, D.K.; Mangini, A. #-------------------- # Description_Notes_and_Keywords # Description: Four stalagmites from Bunker cave - in total covering the last about 11 ka - were investigated. Each stalagmite was 230Th dated. Stable oxgen and carbon isotopes as well as Mg/Ca were measured at high resolution. Using a stacking program a stable oxygen isotope stack of the four stalagmites was generated. #-------------------- # Publication # Authors: Fohlmeister, J., A. Schröder-Ritzrau, D. Scholz, C. Spötl, D.F.C. Riechelmann, M. Mudelsee, A. Wackerbarth, A. Gerdes, S. Riechelmann, A. Immenhauser, D.K. Richter, and A. Mangini # Journal_Name: Climate of the Past # Published_Title: Bunker Cave stalagmites: an archive for central European Holocene climate variability # Published_Date_or_Year: 2012 # Volume: 8 # Pages: 1751-1764 # Issue: # Report_Number: # DOI: 10.5194/cp-8-1751-2012 # Full_Citation: # Abstract: Holocene climate was characterised by variability on multi-centennial to multi-decadal time scales. In central Europe, these fluctuations were most pronounced during winter. Here we present a record of past winter climate variability for the last 10.8 ka based on four speleothems from Bunker Cave, western Germany. Due to its central European location, the cave site is particularly well suited to record changes in precipitation and temperature in response to changes in the North Atlantic realm. We present high-resolution records of d18O, d13C values and Mg/Ca ratios. Changes in the Mg/Ca ratio are attributed to past meteoric precipitation variability. The stable C isotope composition of the speleothems most likely reflects changes in vegetation and precipitation, and variations in the d18O signal are interpreted as variations in meteoric precipitation and temperature. We found cold and dry periods between 8 and 7 ka, 6.5 and 5.5 ka, 4 and 3 ka as well as between 0.7 and 0.2 ka. The proxy signals in the Bunker Cave stalagmites compare well with other isotope records and, thus, seem representative for central European Holocene climate variability. The prominent 8.2 ka event and the Little Ice Age cold events are both recorded in the Bunker Cave record. However, these events show a contrasting relationship between climate and d18O, which is explained by different causes underlying the two climate anomalies. Whereas the Little Ice Age is attributed to a pronounced negative phase of the North Atlantic Oscillation, the 8.2 ka event was triggered by cooler conditions in the North Atlantic due to a slowdown of the thermohaline circulation. #-------------------- # Funding_Agency # Funding_Agency_Name: Deutsche Forschungsgemeinschaft (DFG) # Grant: DFG research grant FG 668 (DAPHNE) #-------------------- # Site_Information # Site_Name: Bunker Cave # Location: Germany # Northernmost_Latitude: 51.3675 # Southernmost_Latitude: 51.3675 # Easternmost_Longitude: 7.6647 # Westernmost_Longitude: 7.6647 # Elevation_m: 184 #-------------------- # Data_Collection # Collection_Name: Bunker2012Bu6 # First_Year: 10258 # Last_Year: 8749 # Time_Unit: cal yr BP # Core_Length_m: # Parameter_Keywords: trace metals, carbon isotopes, oxygen isotopes # Notes: #-------------------- # Chronology_Information # Chronology: Uranium-Thorium # Chronology_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/templates/noaa-wds-paleo-uth-terms.csv # Chronology_Download_Description: Uranium-Thorium terms and definitions. # Chronology_Notes: Samples marked by an asterisk indicate addition of extra Th: Due to the relatively low U content of the samples, Th/U-dating of Holocene speleothems from Bunker Cave using the TIMS method is challenging. Therefore, a Th solution with precisely determined concentration and isotopic composition was added to some sub-samples in order to increase the analysis time for Th and to improve counting statistics. The measured isotope ratios were corrected accordingly, and the uncertainties in concentration and isotope composition of the added Th solution were propagated to the final age errors. This study also employed radiocarbon dating for their age models. # Rejection_Rationale: # 238U_Decay_Constant: Cheng et al., 2000 # 234U_Decay_Constant: Cheng et al., 2000 # 230Th_Decay_Constant: Cheng et al., 2000 # Initial_230Th/232Th: 3.8+/-1.9 (concentration ratio) # Initial_230Th/232Th_Method: # Age_Model_Method: # Missing_Values: na # Chronology_Table: # samp_id depth_top_mm 238U_ppb 238U_2s_ppb 232Th_ppt 232Th_2s_ppt d234U_meas_permil d234U_meas_2s_permil 230Th_238U_act 230Th_238U_act_2s age_uncorr_kaBP1950 age_uncorr_2s_ka age_corr_BP1950 age_corr_2s_yr # Bu6-0.8cm 8 219.1 0.4 1437 8 277 4 0.0996 0.0017 8.93 0.16 8780 180 # Bu6-2.5cm 25 199.4 0.4 333 2 271 5 0.1127 0.0018 10.08 0.18 10040 180 # Bu6-3.8cm 38 237 0.5 2779 14 275 6 0.1190 0.0032 10.86 0.30 10590 340 #-------------------- # 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) # ## age_calBP age,,,calendar year before present,,speleothems,,,N, ## depth_mm depth,,,millimeter,,speleothems,,,N, ## d13CcarbVPDB delta 13C,calcium carbonate,,per mil VPDB,,speleothems,raw,isotope ratio mass spectrometry,N, ## d18OcarbVPDB delta 18O,calcium carbonate,,per mil VPDB,,speleothems,raw,isotope ratio mass spectrometry,N, ## 100*Mg/Ca magnesium/calcium,calcium carbonate,,mole per mole,,speleothems,raw,laser ablation,N,ratio multipied by 100 #-------------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: age_calBP depth_mm d13CcarbVPDB d18OcarbVPDB 100*Mg/Ca 8749 5.4 -10.03 -5.5 0.27 8772.9 5.7 -10.12 -5.56 0.25 8796.8 6 -10.01 -5.52 0.25 8820.7 6.3 -10.15 -5.72 0.24 8844.6 6.6 -10.26 -6.46 0.25 8868.4 6.9 -10.31 -6.28 0.26 8892.3 7.2 -10.3 -5.57 0.24 8916.2 7.5 -10.35 -5.34 0.24 8940.1 7.8 -10.45 -5.23 0.22 8964 8.1 -9.72 -5.37 0.26 8987.9 8.4 -9.56 -5.37 0.26 9011.8 8.7 -9.88 -5.4 0.28 9035.6 9 -10.02 -5.55 0.27 9059.5 9.3 -10.03 -5.44 0.29 9083.4 9.6 -10.02 -5.57 0.26 9107.3 9.9 -10.02 -5.9 0.27 9131.2 10.2 -9.95 -5.89 0.26 9155.1 10.5 -10.02 -5.67 0.26 9178.9 10.8 -9.69 -5.02 0.24 9202.8 11.1 -9.49 -4.7 0.21 9226.7 11.4 -10.01 -5.57 0.23 9250.6 11.7 -9.91 -5.55 0.24 9274.5 12 -9.81 -5.17 0.28 9298.4 12.3 -9.83 -5.31 0.26 9322.3 12.6 -9.93 -5.42 0.22 9346.1 12.9 -9.9 -5.37 0.23 9370 13.2 -9.91 -5.78 0.28 9393.9 13.5 -9.86 -5.92 0.23 9417.8 13.8 -9.95 -6 0.24 9441.7 14.1 -10 -5.96 0.28 9465.6 14.4 -10.13 -6.15 0.27 9489.5 14.7 -10.08 -6.07 0.25 9513.3 15 -10.01 -5.3 0.24 9537.2 15.3 -9.79 -4.85 0.26 9561.1 15.6 -9.68 -5 0.24 9585 15.9 -9.75 -5.01 0.21 9608.9 16.2 -9.81 -5.18 0.2 9632.8 16.5 -10.22 -5.71 0.26 9656.7 16.8 -9.94 -5.49 0.24 9680.5 17.1 -10.04 -5.29 0.22 9704.4 17.4 -10.13 -5.31 0.22 9728.3 17.7 -9.98 -5.15 0.25 9752.2 18 -9.96 -5.06 0.27 9776.1 18.3 -10.12 -5.17 9800 18.6 -10.27 -5.3 9823.9 18.9 -10.52 -5.53 9847.7 19.2 -10.42 -5.71 0.3 9871.6 19.5 -10.5 -5.9 0.3 9895.5 19.8 -10.33 -6 0.32 9919.4 20.1 -10.64 -6.08 0.32 9943.3 20.4 -10.51 -6.15 0.27 9967.2 20.7 -10.43 -6.32 0.27 9991.1 21 -10.29 -5.97 0.23 10014.9 21.3 -10.56 -6.08 0.23 10038.8 21.6 -10.42 -6.37 0.26 10062.7 21.9 -10.35 -6.17 0.25 10086.6 22.2 -10.48 -6.5 0.22 10110.5 22.5 -10.5 -6.59 0.24 10134.4 22.8 -10.49 -6.73 0.24 10158.2 23.1 -10.41 -6.98 0.24 10182.1 23.4 -10.05 -6.61 0.25 10206 23.7 -10.03 -6.54 0.27 10210.8 24 -10.21 -6.33 0.25 10211.8 24.3 -10.33 -6.12 0.25 10212.7 24.6 -10.43 -6.43 0.26 10213.7 24.9 -10.4 -7.18 0.29 10214.7 25.2 -10.38 -7.18 0.29 10215.6 25.5 -10.32 -6.84 0.28 10216.6 25.8 -10.31 -6.29 0.27 10217.6 26.1 -10.22 -6.19 0.27 10218.5 26.4 -10.29 -6.54 0.3 10219.5 26.7 -9.93 -6.03 0.3 10220.5 27 -9.92 -5.98 0.24 10221.4 27.3 -9.83 -5.84 0.29 10222.4 27.6 -9.72 -5.76 0.28 10223.4 27.9 -9.66 -5.79 0.29 10224.3 28.2 -9.57 -5.64 0.27 10225.3 28.5 -9.65 -5.7 0.23 10226.3 28.8 -9.82 -5.85 0.24 10227.2 29.1 -9.75 -5.72 0.24 10228.2 29.4 -9.72 -5.71 0.26 10229.2 29.7 -9.81 -5.8 0.27 10230.1 30 -9.69 -5.67 0.22 10231.1 30.3 -9.79 -5.48 0.23 10232.1 30.6 -9.88 -5.53 0.21 10233 30.9 -9.95 -5.94 0.24 10234 31.2 -10.24 -6.32 0.25 10235 31.5 -9.99 -5.84 0.27 10235.9 31.8 -9.78 -5.59 0.28 10236.9 32.1 -9.77 -5.76 0.27 10237.9 32.4 -9.85 -5.77 0.26 10238.8 32.7 -9.73 -5.59 0.29 10239.8 33 -9.98 -5.89 0.26 10240.8 33.3 -9.87 -5.81 0.25 10241.8 33.6 -10.29 -6.03 0.24 10242.7 33.9 -10.07 -5.89 0.23 10243.7 34.2 -10.15 -5.86 0.27 10244.7 34.5 -10.09 -5.83 0.29 10245.6 34.8 -10.3 -5.77 0.28 10246.6 35.1 -10.78 -6.33 0.3 10247.6 35.4 -10.79 -5.93 0.27 10248.5 35.7 -10.5 -5.69 0.29 10249.5 36 -10.31 -5.84 0.31 10250.5 36.3 -10.4 -6.13 0.29 10251.4 36.6 -10.56 -6.07 0.28 10252.4 36.9 -10.49 -6.13 0.28 10253.4 37.2 -10.65 -6.46 0.33 10254.3 37.5 -10.47 -6.08 0.29 10255.3 37.8 -10.84 -6.57 0.31 10256.3 38.1 -10.82 -6.65 0.32 10257.2 38.4 -10.63 -6.29 0.35 10258.2 38.7 -10.61 -6.38 0.3