# Double Reef, Guam 60 Year Coral Bomb-Produced Radiocarbon Data #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #----------------------------------------------------------------------- # Template Version 2.0 # 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/20346 # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/coral/west_pacific/guam2016d14chighres.txt # # Original_Source_URL: # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Corals and Sclerosponges # # Parameter_Keywords: carbon isotopes #-------------------- # Contribution_Date # Date: 2016-07-18 #-------------------- # Title # Study_Name: Double Reef, Guam 60 Year Coral Bomb-Produced Radiocarbon Data #-------------------- # Investigators # Investigators: Andrews, A.H.; Asami, R.; Iryu, Y.; Kobayashi, D.R.; Camacho, F. #-------------------- # Description_and_Notes # Description: Carbon isotope (D14C) data for the past 60 years from a Porites lobata coral core (GD2) collected from Double Reef, Guam. # Data are subsampled from original core from Asami et al. (2004, 2005) # # Provided Keywords: Carbon-14, environmental radioactivity, fallout, thermonuclear bomb, bomb radiocarbon #-------------------- # Publication # Authors: Andrews, Allen H.; Asami, Ryuji; Iryu, Yasufumi; Kobayashi, Donald R.; Camacho, Frank # Published_Date_or_Year: submitted 2016 # Published_Title: Bomb-produced radiocarbon in the western tropical Pacific Ocean-Guam coral reveals operation-specific signals from the Pacific Proving Grounds # Journal_Name: Journal of Geophysical Research - Oceans # Volume: # Edition: # Issue: # Pages: # Report_Number: # DOI: # Online_Resource: # Full_Citation: # Abstract: High-resolution radiocarbon (14C) analyses on a coral core extracted from Guam, a western tropical Pacific island, revealed a series of early bomb-produced 14C spikes. The typical marine bomb 14C signal-phase lagged and attenuated relative to atmospheric records-is present in the coral and is consistent with other regional coral records. However, 14C levels well above what can be attributed to air-sea diffusion alone punctuate this pattern. This anomaly was observed in other Indo-Pacific coral records, but the Guam record is unmatched in magnitude and temporal resolution. The Guam coral D14C record provided three spikes in 1954-55, 1956-57, and 1958-59 that are superimposed on a normal 14C record. Relative to mean pre-bomb levels, the first peak rises an incredible ~700permil and remained elevated for ~1.2 years. A follow up assay with finer resolution increased the peak by ~300permil. Subsequent spikes were less intense with a rise of ~35permil and ~70permil. Each can be linked to thermonuclear testing in the Pacific Proving Grounds at Bikini and Enewetak atolls in Operations Castle (1954), Redwing (1956), and Hardtack I (1958). These 14C signals can be explained by vaporization of coral reef material in the nuclear fireball, coupled with neutron activation of atmospheric nitrogen (14C production), and subsequent absorption of 14CO2 to form particulate carbonates of close-in fallout. The lag time in reaching Guam and other coral records abroad was tied to ocean surface currents and modeling provided validation of 14C arrival observations. #------------------ # Funding_Agency # Funding_Agency_Name: US NOAA National Marine Fisheries Service Saltonstall Kennedy program # Grant: NA14NMF4270056 #------------------ # Site_Information # Site_Name: Double Reef # Location: Ocean>Pacific Ocean>Central Pacific Ocean>Guam # Country: United States Of America # Northernmost_Latitude: 13.598183 # Southernmost_Latitude: 13.598183 # Easternmost_Longitude: 144.83588 # Westernmost_Longitude: 144.83588 # Elevation: -4.5 m #------------------ # Data_Collection # Collection_Name: GD2D14Chighres # Earliest_Year: 1954 # Most_Recent_Year: 1959 # Time_Unit: AD # Core_Length: m # Notes: #------------------ # Chronology_Information # Chronology: # #---------------- # Variables # # Data variables follow are preceded by "##" in columns one and two. # Data line variables format: Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # ## ID Sample ID,,,,,,,,C ## Acc# Accession Number,,,,,,,,C ## age_AD age, , , AD, , , , ,N ## fracmod Fraction modern, , , , , , , ,N ## d13Ccarb delta13C, calcium carbonate, , per mil, ,coral, , ,N ## D14Ccorr Delta14C corrected, calcium carbonate, , per mil, ,coral, , t-corrected,N ## D14Cerr Delta14C error, calcium carbonate, , per mil, ,coral, , ,N # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: # # Appendix II - Radiocarbon data reported as D14C from the high-resolution sample series extracted from the Guam coral core within the spike periods of # 1954–55, 1956–57 and 1958–59. The reported Fraction modern values were corrected online (during AMS measurement) and F14C is used to unambiguously # symbolize fractionation corrected values [Reimer et al., 2004]. A partitioned sample provided a robust and sample-specific d13C value. # ID Acc# age_AD fracmod d13Ccarb D14Ccorr D14Cerr GD2-240-1, HiRes-1 OS-117846 1959.500 0.9715 -2.7 -29.6 2.0 GD2-240-2, HiRes-2 OS-117869 1959.389 0.9777 -1.8 -23.4 2.0 GD2-241-1, HiRes-3 OS-117847 1959.278 0.9861 -2.2 -15.0 2.4 GD2-241-2, HiRes-4 OS-117848 1959.167 1.0118 -1.9 10.7 2.1 GD2-242-1, HiRes-5 OS-117849 1959.038 1.0259 -2.4 24.8 2.0 GD2-242-2, HiRes-6 OS-117871 1958.962 1.0375 -1.9 36.4 2.1 GD2-243-1, HiRes-7 OS-117872 1958.886 1.0293 -1.8 28.2 2.2 GD2-243-2, HiRes-8 OS-117850 1958.809 0.9985 -1.8 -2.6 2.2 GD2-244-1, HiRes-9 OS-117851 1958.732 0.975 -1.0 -26.0 1.9 GD2-244-2, HiRes-10 OS-117873 1958.655 0.9655 -1.4 -35.5 1.9 GD2-251-1, HiRes-11 OS-117874 1957.626 0.9732 -1.2 -27.7 1.9 GD2-251-2, HiRes-12 OS-117875 1957.542 0.9682 -1.3 -32.7 1.9 GD2-252-1, HiRes-13 OS-117859 1957.459 0.9753 -1.5 -25.6 2.0 GD2-252-2, HiRes-14 OS-117876 1957.375 0.9914 -1.9 -9.5 1.9 GD2-253-1, HiRes-15 OS-117877 1957.292 1.0035 -1.7 2.6 2.2 GD2-253-2, HiRes-16 OS-117878 1957.208 0.9961 -1.8 -4.8 1.9 GD2-254-1, HiRes-17 OS-117879 1957.129 1.0051 -1.9 4.2 2.2 GD2-254-2, HiRes-18 OS-117880 1957.037 0.9942 -1.9 -6.6 2.8 GD2-255-1, HiRes-19 OS-117881 1956.950 0.9792 -2.2 -21.6 2.2 GD2-255-2, HiRes-20 OS-117882 1956.850 0.9732 -1.7 -27.6 2.5 GD2-256-1, HiRes-21 OS-118097 1956.750 0.9619 -1.8 -38.9 1.9 GD2-256-2, HiRes-22 OS-118098 1956.650 0.9612 -1.5 -39.6 1.9 GD2-262-1, HiRes-23 OS-118099 1955.679 0.9686 -2.0 -32.1 2.5 GD2-262-2, HiRes-24 OS-118100 1955.607 0.9742 -1.9 -26.5 1.9 GD2-263-1, HiRes-25 OS-118101 1955.531 0.9837 -1.1 -17.0 2.1 GD2-263-2, HiRes-26 OS-118102 1955.469 0.9950 -1.3 -5.7 2.5 GD2-264-1, HiRes-27 OS-117860 1955.415 1.0113 -1.0 10.6 2.1 GD2-264-2, HiRes-28 OS-118103 1955.335 1.0272 -1.5 26.5 2.0 GD2-265-1, HiRes-29 OS-118104 1955.250 1.0377 -1.7 37.0 2.2 GD2-265-2, HiRes-30 OS-118105 1955.178 1.0623 -1.7 61.6 2.1 GD2-266-1, HiRes-31 OS-118106 1955.109 1.1343 -2.0 133.6 2.4 GD2-266-2, HiRes-32 OS-118107 1955.033 1.1602 -2.4 159.5 2.4 GD2-267-1, HiRes-33 OS-118108 1954.960 1.1306 -2.3 129.9 2.2 GD2-267-2, HiRes-34 OS-118109 1954.876 1.1810 -2.0 180.3 2.4 GD2-268-1, HiRes-35 OS-118110 1954.793 1.5141 -1.6 513.2 3.0 GD2-268-2, HiRes-36 OS-117861 1954.709 1.9387 -1.2 937.6 4.1 GD2-269-1, HiRes-37 OS-118111 1954.626 1.2078 -0.8 207.1 2.4 GD2-269-2, HiRes-38 OS-118112 1954.542 0.9865 -0.9 -14.0 1.9 GD2-270-1, HiRes-39 OS-118113 1954.459 0.9651 -1.1 -35.4 2.1 GD2-270-2, HiRes-40 OS-118281 1954.375 0.9520 -1.6 -48.5 2.2 GD2-271-1, HiRes-41 OS-118114 1954.292 0.9459 -1.5 -54.6 1.9 GD2-271-2, HiRes-42 OS-118115 1954.208 0.9482 -1.8 -52.3 2.0