noaa-ocean-17675 Southwest Atlantic Deglacial Planktonic and Benthic D14C Data Sortor, R.N.; Lund, D.C. Southwest Atlantic Deglacial Planktonic and Benthic D14C Data 2015-01-05 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/17675 Investigator R.N. Sortor Investigator D.C. Lund earth science paleoclimate paleoceanography age,null,one standard deviation upper bound,calendar year before present,null,paleoceanography,null,null,N,CALIB 6.0 - MARINE09 earth science paleoclimate paleoceanography Delta 14C,foraminifer,null,per mil,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography notes,null,null,null,null,paleoceanography,null,null,N,Modern Fraction earth science paleoclimate paleoceanography age,null,null,calendar year before present,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography age,null,null,radiocarbon year before present,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography age,null,unspecified margin of error,radiocarbon year before present,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography age,null,unspecified margin of error,calendar year before present,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography age,null,one standard deviation,calendar year before present,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography notes,null,null,null,null,paleoceanography,null,null,C,Genera earth science paleoclimate paleoceanography age,null,one standard deviation lower bound,calendar year before present,null,paleoceanography,null,null,N,CALIB 6.0 - MARINE09 earth science paleoclimate paleoceanography age,null,null,calendar year before present,null,paleoceanography,null,null,N,CALIB 6.0 - MARINE09 earth science paleoclimate paleoceanography notes,null,null,null,null,paleoceanography,null,null,N,Modern Fraction unspecified rror earth science paleoclimate paleoceanography notes,null,null,null,null,paleoceanography,null,null,C,Species earth science paleoclimate paleoceanography notes,null,null,null,null,paleoceanography,null,null,N,UCIAMS sample number earth science paleoclimate paleoceanography depth,null,null,centimeter,null,paleoceanography,null,null,N,null earth science paleoclimate paleocean carbon isotopes geoscientificInformation 20110 cal yr BP 4730 cal yr BP Complete -27.5167 -27.5167 -46.4667 -46.4667 -1268 -1268 Ocean Atlantic Ocean South Atlantic Ocean KNR159-5-36GGC>LATITUDE -27.5167>LONGITUDE -46.4667 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Rachel N. Sortor and David C. Lund 2011 Earth and Planetary Science Letters 310 1-2 65-72 10.1016/j.epsl.2011.07.017 http://www.sciencedirect.com/science/article/pii/S0012821X1100433X

The last deglaciation was characterized by an increase in atmospheric pCO2 and decrease in atmospheric radiocarbon activity. One hypothesis is that these changes were due to out-gassing of 14C-depleted carbon from the abyssal ocean. Reconstructions of foraminiferal D14C from the eastern tropical Pacific, Arabian Sea, and high latitude North Atlantic show that severe depletions in 14C occurred at intermediate water depths during the last deglaciation. It has been suggested that 14C-depleted water from the abyss upwelled in the Southern Ocean and was then carried by Antarctic Intermediate Water (AAIW) to these sites. However, locations in the South Pacific in the direct path of modern-day AAIW do not exhibit the D14C excursion and therefore cast doubt upon the AAIW mechanism (De Pol-Holz et al., 2010 and Rose et al., 2010). Here we evaluate whether or not a deglacial 14C anomaly occurred at intermediate depths in the Southwest Atlantic. We find that the deglacial benthic D14C trend at our site is similar to the atmospheric D14C trend. Our results are also largely consistent with results from U/Th-dated corals at shallower water depths on the Brazil Margin (Mangini et al., 2010). We find no evidence in the southwestern Atlantic of a ~300 per mil decrease in intermediate water D14C from 18 to 14 kyr BP like that observed in the eastern tropical Pacific (Marchitto et al., 2007). When our results are paired with those from the South Pacific, it appears AAIW did not carry a highly 14C-depleted signal during the deglaciation. Another source of carbon is apparently required to explain the intermediate-depth D14C anomalies in the North Atlantic, Indian, and Pacific Oceans. STUDY NOTES: Planktonic and benthic foraminiferal D14C data from southwest Atlantic core KNR-159-5-36GGC for the deglacial period (~18-14 KYrBP).

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/sortor2011/sortor2011benth.txt Data File; Benthic radiocarbon data KNR159-5-36GGC GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/sortor2011/sortor2011plank.txt Data File; Planktonic radiocarbon data KNR159-5-36GGC USA/NOAA DIF Version 9.8.4 2019-06-06 2019-06-06