36758 Guam coral radiocarbon record Data Set Published / External 74891 Life History Estimates Project Completed 2016 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 ¿14C 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 ~700‰ and remained elevated for ~1.2 years. A follow up assay with finer resolution increased the peak by ~300‰. Subsequent spikes were less intense with a rise of ~35‰ and ~70‰. 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. Establish a comprehensive bomb radiocarbon reference for use in age validation of regional marine organisms and to explain the oceanographic propagation of the signal through the western Pacific Ocean. Data set also available via the NOAA Climatic Data Center Double Reef, Guam 60 Year Coral Bomb-Produced Radiocarbon Data https://www.ncdc.noaa.gov/paleo/study/20346 Publication: Andrews, A.H., R. Asami, Y. Iryu, D.R. Kobayashi, and F. Camacho. 2016. Bomb-produced radiocarbon in the western tropical Pacific Ocean—Guam coral reveals operation-specific signals from the Pacific Proving Grounds. Journal of Geophysical Research – Oceans 121: 6351-6366 (dx.doi.org/10.1002/2016JC012043) Pacific Islands Fisheries Science Center Honolulu HI USA Data Set Excel and SAS Dataset None Planned Document (digital) Accelerator Mass Spectrometer NA Coring device 46901 GUAM_CORAL_HIGH_RES Published / External Completed Appendix II - Radiocarbon data reported as D14C from the high-resolution sample series extracted from the Guam coral core within the spike periods of 195455, 195657 and 195859. 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. Data Table Yes Appendix II - Radiocarbon data reported as D14C from the high-resolution sample series extracted from the Guam coral core within the spike periods of 195455, 195657 and 195859. 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. 1 ID Character 22 No No Active Sample ID, coral, calcium carbonate. Character 2 ACCNUM Character 22 No No Active Accession Number. Character 3 AGE_AD Number 22 No No Active Date of formation, AD. Number 4 FRACMOD Number 22 No No Active Fraction Modern, ratio of 14C/12C. Number 5 D13CCARB Number 22 No No Active Delta13c, parts per million. Number 6 D14CCORR Number 22 No No Active Delta14c corrected, parts per million, date/time-corrected. Number 7 D14CERR Number 22 No No Active Delta14c error, parts per million. Number 46902 GUAM_CORAL_REPLICATE Published / External Completed Appendix III - A replicate sample series (parenthetical numbers) was performed to test elevated values, but revealed there was contamination near actively growing region of the coral. Deviations from expected trend on the order of 10 per mil (> 2 SD) were eliminated from further consideration. Both GD2-004 samples were deemed contaminated and removed from the analysis. Data Table Yes Appendix III - A replicate sample series (parenthetical numbers) was performed to test elevated values, but revealed there was contamination near actively growing region of the coral. Deviations from expected trend on the order of 10 per mil (> 2 SD) were eliminated from further consideration. Both GD2-004 samples were deemed contaminated and removed from the analysis. 1 ID Character 22 No No Active Sample ID, coral, calcium carbonate. Character 2 AGE_AD Number 22 No No Active Date of formation, AD. Number 3 D14CCORR Number 22 No No Active Delta14c corrected A sample, parts per million, date/time-corrected. Number 4 D14CERR Number 22 No No Active Delta14c error, parts per million. Number 5 D14CCORRB Number 22 No No Active Delta14c corrected B sample, parts per million, date/time-corrected. Number 6 D14CDIFF Number 22 No No Active Delta14c difference between A and B samples, parts per million. Number 46904 GUAM_CORAL_DATA Published / External Completed Appendix I - Radiocarbon data reported as D14C from the sample series extracted from the Guam coral core with the validated date of formation. 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. Data Table Yes Appendix I - Radiocarbon data reported as D14C from the sample series extracted from the Guam coral core with the validated date of formation. 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. 1 ID Character 22 No No Active Sample ID, coral, calcium carbonate. Character 2 ACCNUM Character 22 No No Active Accession Number, * = 1st run replaced with decontaminated value (Appendix III). Character 3 AGE_AD Number 22 No No Active Date of formation, AD. Number 4 FRACMOD Number 22 No No Active Fraction Modern, ratio of 14C/12C. Number 5 D13CCARBVPDB Number 22 No No Active Delta13c, parts per million. Number 6 D14CCORR Number 22 No No Active Delta14c corrected, parts per million, date/time-corrected. Number 7 D14CERR Number 22 No No Active Delta14c error, parts per million. Number Data Steward 2019-04-01 2023-05 Person O'Malley, Joseph M joseph.omalley@noaa.gov 1845 Wasp Blvd. Honolulu HI 96818 USA (808)725-5741 Contact via email Data Steward 2016 2018-09 Person Boggs, Christofer H christofer.boggs@noaa.gov 1845 Wasp Blvd. Honolulu HI 96818 USA (808)725-5364 Distributor 2016 Organization Pacific Islands Fisheries Science Center PIFSC pifsc.info@noaa.gov https://ror.org/02apffz65 1845 Wasp Blvd. Honolulu HI 96818 USA 808-725-5360 https://www.pifsc.noaa.gov Pacific Island Fisheries Science Center homepage Online Resource 8:00 a.m. - 4:30 p.m. Metadata Contact 2019-04-01 2023-05 Person O'Malley, Joseph M joseph.omalley@noaa.gov 1845 Wasp Blvd. Honolulu HI 96818 USA (808)725-5741 Contact via email Metadata Contact 2016 2019-03-31 Person Andrews, Allen H allen.andrews@noaa.gov https://orcid.org/0000-0002-9001-8305 1845 Wasp Blvd. Honolulu HI 96818 USA (808)725-5373 Point of Contact 2023-08 Person Schemmel, Eva M eva.schemmel@noaa.gov Contact via email. Point of Contact 2019-04-01 2023-05 Person O'Malley, Joseph M joseph.omalley@noaa.gov 1845 Wasp Blvd. Honolulu HI 96818 USA (808)725-5741 Contact via email Point of Contact 2016 2019-03-31 Person Andrews, Allen H allen.andrews@noaa.gov https://orcid.org/0000-0002-9001-8305 1845 Wasp Blvd. Honolulu HI 96818 USA (808)725-5373 Publication Date Guam, US Territory Range 1939 2000 Validated timeline for the coral core radiocarbon record using previously published seasonal/annual temperature changes. Unclassified NA NA NA NA NA NA NA NA https://www.ncdc.noaa.gov/paleo/study/20346 Guam 14C Data Further QC after data entry. Yes Unknown No No NCDC None Other None PIFSC ITS performs scheduled back-ups. See publication: Andrews, A.H., R. Asami, Y. Iryu, D.R. Kobayashi, and F. Camacho. 2016. Bomb-produced radiocarbon in the western tropical Pacific Ocean—Guam coral reveals operation-specific signals from the Pacific Proving Grounds. Journal of Geophysical Research – Oceans 121: 6351-6366 (dx.doi.org/10.1002/2016JC012043) 46904 Entity 46901 Entity 46902 Entity gov.noaa.nmfs.inport:36758 Allen Andrews 2017-02-10T15:19:27 SysAdmin InPortAdmin 2026-03-04T19:17:18 2025-02-13 Pacific Islands Fisheries Science Center PIFSC 1845 Wasp Blvd. Honolulu HI 96818 USA 808-725-5300 https://www.pifsc.noaa.gov 8:00 a.m. - 4:30 p.m. 1001 Public No No 2019-07-23 1 Year 2020-07-23