Skip to main content

Temporal Variability of Dissolved Organic Radiocarbon in the Deep North Pacific Ocean

  • Ellen R M Druffel (a1), Sheila Griffin (a1), Ning Wang (a1) (a2) and Brett D Walker (a1)

We report marine dissolved organic carbon (DOC) ∆14C from seawater collected from the North central Pacific Ocean (NCP) in 2015. These measurements show DOC ∆14C values averaged –235±5‰ (n=3) in the mixed layer (24–81 m) and –544±5‰ (n=5) in the deep water (1500–5139 m). A comparison of these data with two previously published DOC ∆14C profiles from the NCP in 1985 and 1987 reveals that deep DOC ∆14C values have decreased. We discuss several possible mechanisms that could cause such a shift in DOC ∆14C values, including spatial inhomogeneity and temporal variability due to changes in the dissolution and ∆14C value of surface derived particles in the deep sea. We find that forthcoming profiles of DOC ∆14C results from the NCP will determine the primary mechanisms controlling deep DOC ∆14C distributions, and changes over the past three decades.

Corresponding author
*Corresponding author. Email:
Hide All
Andrews, A, Siciliano, D, Potts, D, DeMartini, E, Covarrubias, S. 2016. Bomb radiocarbon and the Hawaiian Archipelago: Coral, otoliths and seawater. Radiocarbon 58(3):531548.
Bauer, JE, Williams, PM, Druffel, ERM. 1992. 14C activity of dissolved organic carbon fractions in the north central Pacific and Sargasso Sea. Nature 357:667670.
Bauer, JE, Druffel, ERM, Williams, PM, Wolgast, DM, Griffin, S. 1998. Inter- and intra-annual variability in isotopic (14C and 13C) signatures of dissolved organic carbon in the eastern North Pacific Ocean. Journal of Geophysical Research 103:28672882.
Beaupré, SR, Druffel, ERM, Griffin, S. 2007. A low-blank photochemical extraction system for concentration and isotopic analyses of marine dissolved organic carbon. Limnology and Oceanography Methods 5:174184.
Beaupré, SR, Druffel, ERM. 2009. Constraining the propagation of bomb-radiocarbon through the dissolved organic carbon (DOC) pool in the northeast Pacific Ocean. Deep-Sea Research I 56:17171726.
Bien, GS, Rakestraw, NW, Suess, HE. 1965. Radiocarbon in the Pacific and Indian Oceans and its relation to deep water movements. Limnology and Oceanography 10:R25R37.
Broecker, WS, Gerard, R, Ewing, M, Heezin, B. 1960. Natural radiocarbon in the Atlantic Ocean. Journal of Geophysical Research 65:29032931.
Druffel, E, Williams, P, Bauer, J, Ertel, J. 1992. Cycling of dissolved and particulate organic matter in the open ocean. Journal of Geophysical Research 97:1563915659.
Druffel, ERM, Bauer, JE. 2000. Radiocarbon distributions in Southern Ocean dissolved and particulate organic carbon. Geophysical Research Letters 27:14951498.
Druffel, ERM, Griffin, S. 2008. Daily variability of dissolved inorganic radiocarbon at three sites in the surface ocean. Marine Chemistry 110:185189.
Druffel, ERM, Griffin, S, Walker, BD, Coppola, AI, Glynn, DS. 2013. Total uncertainty of radiocarbon measurements of marine dissolved organic carbon and methodological recommendations. Radiocarbon 55(2–3):11351141.
Druffel, ERM, Griffin, S, Walker, BD, Coppola, AI. 2016. Radiocarbon in dissolved organic carbon of the Atlantic Ocean. Geophysical Research Letters 43. doi: 10.1002/2016GL068746.
Druffel, ERM, Griffin, S. 2015. Radiocarbon in dissolved organic carbon of the South Pacific Ocean. Geophysical Research Letters 42:40964101.
Falkowski, PG. 2014. The biogeochemistry of primary production in the sea. Treatise on Geochemistry (Second Edition) 10. Biogeochemistry. 163187.
Griffin, S, Beaupré, SR, Druffel, ERM. 2010. An alternate method of diluting dissolved organic carbon seawater samples for 14C analysis. Radiocarbon 52(2):12241229.
Griffith, DR, McNichol, AP, Xu, L, McLaughlin, FA, MacDonald, RW, Brown, KA, Eglinton, TI. 2012. Carbon dynamics in the western Arctic Ocean: insights from full-depth carbon isotope profiles of DIC, DOC, and POC. Biogeosciences 9:12171224.
Hansell, DA, Carlson, CA, Repeta, DJ, Schlitzer, R. 2009. Dissolved organic matter in the ocean: A controversy stimulates new insights. Oceanography 22:202211.
Hansman, RS, Griffin, S, Watson, J, Druffel, ERM, Ingalls, A, Pearson, A, Aluwihare, A. 2009. The radiocarbon signature of microorganisms in the mesopelagic ocean. Proceedings of the National Academy of Sciences 106:65136518.
Hawkes, JA, Rossel, PE, Stubbins, A, Butterfield, D, Connelly, DP, Achterberg, EP, Koschinsky, A, Chavagnac, V, Hansen, CT, Bach, W, Dittmar, T. 2015. E fficient removal of recalcitrant deep-ocean dissolved organic matter during hydrothermal circulation. Nature Geoscience 8:856861.
Komada, T, Burdige, D, Cripso, S, Druffel, E, Griffin, S, Johnson, L, Le, D. 2013. Dissolved organic carbon dynamics in anaerobic sediments of the Santa Monica Basin. Geochimica et Cosmochimica Acta 110:253273.
Lang, SQ, Butterfield, DA, Lilley, MD, Johnson, HP, Hedges, JI. 2006. Dissolved organic carbon in ridge-axis and ridge-flank hydrothermal systems. Geochimica et Cosmochimica Acta 70:38303842.
McCarthy, MD, Beaupré, SR, Walker, BD, Voparil, I, Guilderson, TP, Druffel, ERM. 2011. Chemosynthetic origin of 14C-depleted dissolved organic matter in a ridge-flank hydrothermal system. Nature Geoscience 4:3236.
McNichol, AP, Druffel, ERM. 1992. Variability of the d13C of dissolved inorganic carbon at a site in the North Pacific Ocean. Geochimica et Cosmochimica Acta 56:35893592.
Pohlman, J, Bauer, J, Waite, W, Osburn, C, Chapman, N. 2011. Methane hydrate-bearing seeps as a source of aged dissolved organic carbon to the oceans. Nature Geoscience 4:3741.
Smith, KL. 1989. Short time-series measurements of particulate organic carbon flux and sediment community oxygen consumption in the North Pacific. Deep Sea Res 36:11111119.
Sonnerup, R, Quay, P, McNichol, A. 2000. The Indian Ocean 13C Suess effect. Global Biogeochemical Cycles. doi: 10.1029/1999GB001244.
Southon, JR, Santos, M, Druffel-Rodriguez, KC, Druffel, ERM, Trumbore, SE, Xu, X, Griffin, S, Ali, S, Mazon, M. 2004. The Keck Carbon Cycle AMS Laboratory, U.C.I.: Initial operation and a background surprise. Radiocarbon 46(1):4150.
Stuiver, M, Polach, HA. 1977. Discussion: Reporting of 14C data. Radiocarbon 19(3):355363.
Tanaka, N, Otosaka, S, Wakita, M, Amano, H, Togawa, O. 2010. Preliminary result of dissolved organic radiocarbon in the western North Pacific Ocean. Nuclear Instruments and Methods Physics Research 268:12191221.
Walker, BD, Griffin, S, Druffel, ERM. 2016. Linked changes in marine dissolved organic carbon molecular size and radiocarbon age. Radiocarbon 58. DOI: 10.1017/RDC.2016.48.
Williams, PM, Druffel, ERM. 1987. Radiocarbon in dissolved organic carbon in the central North Pacific Ocean. Nature 330:246248.
Williams, PM, Oeschger, H, Kinney, P. 1969. Natural radiocarbon activity of dissolved organic carbon in northeast Pacific Ocean. Nature 224(5216):256–248.
Xu, X, Trumbore, SE, Zheng, S, Southon, JR, McDuffee, KE, Luttgen, M, Liu, JC. 2007. Modifying a sealed tube zinc reduction method for preparation of AMS graphite targets: Reducing background and attaining high precision. Nuclear Instruments and Methods in Physics Research B 259:320329.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

  • ISSN: 0033-8222
  • EISSN: 1945-5755
  • URL: /core/journals/radiocarbon
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed