Melgar-González, Lucia; González-González, Beatriz; Baumas, Chloe; Villa-Alfageme, María: Global particulate organic carbon flux derived from Th-234: 13 ocean regions, 3 export depths [dataset]. PANGAEA, https://doi.pangaea.de/10.1594/PANGAEA.986750 (dataset in review)
Abstract:
The 234Th–238U disequilibrium technique has been widely used to estimate the amount of particulate organic carbon (POC) exported from surface ocean layers to the deep sea. This method is based on determining 234Th fluxes from vertical 234Th–238U profiles in the water column and converting them into POC fluxes using POC/234Th ratios measured in sinking particles at a given calculation depth.
We present here an extensive repository of POC fluxes, together with Th fluxes and POC/234Th ratios. Covering all the global ocean, classified in 13 regions, season and moment of the bloom and calculated at three different depths:
i) a fixed depth (100 m)
ii) the reference depth in the paper associated to the base of the euphotic zone
iii) the 234Th–238U equilibrium depth.
To ensure a compilation representative of the global ocean, the dataset were selected using the division areas proposed by the international network JETZON (Joint Exploration of the Twilight Zone Ocean Network); that agreed a division of the oceans in 13 regions based on their contrasted physics and biogeochemical characteristics. The stations from 234Th publications associated to each JETZON region were carefully selected according to their ability to represent regional environmental conditions. Furthermore, station selection was based on essential criteria such as data quality and accessibility, availability of time series, clear definition of export depth, measurements from established programs, e.g. GEOTRACES, and the presence of other additional relevant ancillary data.
The data in the compilation are thus organized by region and include geographic coordinates, season, selected export depth, and other key factors (such as a description of the flux evaluation depth or the export depth zone).
After 234Th–238U compilation, 234Th fluxes were calculated, when possible, at the three different depths, i), ii) and iii), under the assumption of steady-state conditions, following Le Moigne et al. 2013.
Using POC/234Th ratios, POC fluxes are estimated from Th fluxes and both fluxes were included in the repository.
POC/234Th ratios were chosen from pump samples, prioritizing particles larger than 53 μm when available. These ratios must be estimated at the flux calculation depth [i), ii) and iii)]. When they were not available at the calculation depth POC/234Th values were interpolated as described in the readme text file. The values of the ratios are included in the repository, specifying the depth at which they were determined and indicating whether they have been interpolated. Similarly, when 234Th, 238U concentrations were not available at the calculation depth, values were interpolated (see readme text file).
Source:
Bacon, Michael P; Cochran, J Kirk; Hirschberg, David J; Fleer, Alan P (1996): Export flux of carbon at the equator during the EqPac time-series cruises estimated from 234Th measurements. Deep Sea Research Part II: Topical Studies in Oceanography, 43(4-6), 1133-1153, https://doi.org/10.1016/0967-0645(96)00016-1
Benitez-Nelson, Claudia R; Buesseler, Ken O; Karl, David Michael; Andrews, John A (2001): A time-series study of particulate matter export in the North Pacific Subtropical Gyre based on 234Th:238U disequilibrium. Deep Sea Research Part I: Oceanographic Research Papers, 48(12), 2595-2611, https://doi.org/10.1016/S0967-0637(01)00032-2
Black, Erin; Buesseler, Ken O; Pike, Steven M; Lam, Phoebe J (2018): 234Th as a tracer of particulate export and remineralization in the southeastern tropical Pacific. Marine Chemistry, 201, 35-50, https://doi.org/10.1016/j.marchem.2017.06.009
Brew, H S; Moran, S Bradley; Lomas, Michael W; Burd, Adrian B (2009): Plankton community composition, organic carbon and thorium-234 particle size distributions, and particle export in the Sargasso Sea. Journal of Marine Research, 67(6), 845-868, https://doi.org/10.1357/002224009792006124
Buesseler, Ken O; Andrews, John A; Hartman, Mary C; Belastock, Rebecca; Chai, Fei (1995): Regional estimates of the export flux of particulate organic carbon derived from thorium-234 during the JGOFS EqPac program. Deep Sea Research Part II: Topical Studies in Oceanography, 42(2-3), 777-804, https://doi.org/10.1016/0967-0645(95)00043-P
Buesseler, Ken O; Ball, Lary A; Andrews, James; Benitez-Nelson, Claudia R; Belastock, Rebecca; Chai, Fei; Chao, Yi (1998): Upper ocean export of particulate organic carbon in the Arabian Sea derived from Thorium-234. Deep Sea Research Part II: Topical Studies in Oceanography, 45(10-11), 2461-2487, https://doi.org/10.1016/S0967-0645(98)80022-2
Buesseler, Ken O; Benitez-Nelson, Claudia R; Roca-Martí, Montserrat; Wyatt, Abigale M; Resplandy, Laure; Clevenger, Samantha J; Drysdale, Jessica A; Estapa, Margaret L; Pike, Steven M; Umhau, Blaire P (2020): High-resolution spatial and temporal measurements of particulate organic carbon flux using thorium-234 in the northeast Pacific Ocean during the EXport Processes in the Ocean from RemoTe Sensing field campaign. Elementa - Science of the Anthropocene, 8(1), 030, https://doi.org/10.1525/elementa.2020.030
Buesseler, Ken O; McDonnell, Andrew; Schofield, Oscar; Steinberg, Deborah K; Ducklow, Hugh W (2010): High particle export over the continental shelf of the west Antarctic Peninsula. Geophysical Research Letters, 37(22), L22606, https://doi.org/10.1029/2010GL045448
Ceballos-Romero, Elena; Le Moigne, Frédéric A C; Henson, Stephanie A; Marsay, Christopher M; Sanders, Richard J; García-Tenorio, Rafael; Villa-Alfageme, María (2016): Influence of bloom dynamics on Particle Export Efficiency in the North Atlantic: a comparative study of radioanalytical techniques and sediment traps. Marine Chemistry, 186, 198-210, https://doi.org/10.1016/j.marchem.2016.10.001
Charette, Matthew A; Moran, S Bradley (1999): Rates of particle scavenging and particulate organic carbon export estimated using 234Th as a tracer in the subtropical and equatorial Atlantic Ocean. Deep Sea Research Part II: Topical Studies in Oceanography, 46(5), 885-906, https://doi.org/10.1016/S0967-0645(99)00006-5
Charette, Matthew A; Moran, S Bradley; Bishop, James K B (1999): 234Th as a tracer of particulate organic carbon export in the subarctic Northeast Pacific Ocean. Deep Sea Research Part II: Topical Studies in Oceanography, 46(11-12), 2833-2861, https://doi.org/10.1016/S0967-0645(99)00085-5
Coppola, L; Roy-Barman, Matthieu; Mulsow, S; Povinec, Pavel Peter; Jeandel, Catherine (2005): Low particulate organic carbon export in the frontal zone of the Southern Ocean (Indian sector) revealed by 234Th. Deep Sea Research Part I: Oceanographic Research Papers, 52(1), 51-68, https://doi.org/10.1016/j.dsr.2004.07.020
Gustafsson, Örjan; Andersson, Per S (2012): 234Th-derived surface export fluxes of POC from the Northern Barents Sea and the Eurasian sector of the Central Arctic Ocean. Deep Sea Research Part I: Oceanographic Research Papers, 68, 1-11, https://doi.org/10.1016/j.dsr.2012.05.014
Kawakami, Hajime; Honda, Makio C (2007): Time-series observation of POC fluxes estimated from 234Th in the northwestern North Pacific. Deep Sea Research Part I: Oceanographic Research Papers, 54(7), 1070-1090, https://doi.org/10.1016/j.dsr.2007.04.005
Kawakami, Hajime; Honda, Makio C; Matsumoto, Kazuhiko; Fujiki, Toshiyuki; Watanabe, Shuichi (2010): East-west distribution of POC fluxes estimated from 234Th in the northern North Pacific in autumn. Journal of Oceanography, 66(1), 71-83, https://doi.org/10.1007/s10872-010-0006-z
Lalande, Catherine; Lepore, Kate; Cooper, Lee W; Grebmeier, Jacqueline M; Moran, S Bradley (2007): Export fluxes of particulate organic carbon in the Chukchi Sea: A comparative study using 234Th/238U disequilibria and drifting sediment traps. Marine Chemistry, 103(1-2), 185-196, https://doi.org/10.1016/j.marchem.2006.07.004
Lalande, Catherine; Moran, S Bradley; Wassmann, Paul; Grebmeier, Jacqueline M; Cooper, Lee W (2008): 234Th-derived particulate organic carbon fluxes in the northern Barents Sea with comparison to drifting sediment trap fluxes. Journal of Marine Systems, 73(1-2), 103-113, https://doi.org/10.1016/j.jmarsys.2007.09.004
Le Moigne, Frédéric A C; Villa-Alfageme, María; Sanders, Richard J; Marsay, Christopher M; Henson, Stephanie A; García-Tenorio, R (2013): Export of organic carbon and biominerals derived from 234Th and 210Po at the Porcupine Abyssal Plain. Deep Sea Research Part I: Oceanographic Research Papers, 72, 88-101, https://doi.org/10.1016/j.dsr.2012.10.010
Lemaitre, Nolwenn; Planchon, Frédéric; Planquette, Hélène; Dehairs, Frank; Fonseca-Batista, Debany; Roukaerts, Arnout; Deman, Florian; Tang, Yi; Mariez, Clarisse; Sarthou, Géraldine (2018): High variability of particulate organic carbon export along the North Atlantic GEOTRACES section GA01 as deduced from 234Th fluxes. Biogeosciences, 15(21), 6417-6437, https://doi.org/10.5194/bg-15-6417-2018
Moran, S Bradley; Kelly, Roger P; Hagstrom, K; Smith, John Norton; Grebmeier, Jacqueline M; Cooper, Lee W; Cota, Glenn; Walsh, John J; Bates, Nicolas R; Hansell, Dennis A; Maslowski, Weislaw; Nelson, Richard P; Mulsow, Sandor (2005): Seasonal changes in POC export flux in the Chukchi Sea and implications for water column-benthic coupling in Arctic shelves. Deep Sea Research Part II: Topical Studies in Oceanography, 52(24-26), 3427-3451, https://doi.org/10.1016/j.dsr2.2005.09.011
Morris, Paul J; Sanders, Richard J; Turnewitsch, Robert; Thomalla, Sandy J (2007): 234Th-derived particulate organic carbon export from an island-induced phytoplankton bloom in the Southern Ocean. Deep Sea Research Part II: Topical Studies in Oceanography, 54(18-20), 2208-2232, https://doi.org/10.1016/j.dsr2.2007.06.002
Owens, Stephanie A; Pike, Steven M; Buesseler, Ken O (2015): Thorium-234 as a tracer of particle dynamics and upper ocean export in the Atlantic Ocean. Deep Sea Research Part II: Topical Studies in Oceanography, 116, 42-59, https://doi.org/10.1016/j.dsr2.2014.11.010
Planchon, F; Cavagna, Anne-Julie; Cardinal, Damien; André, Luc; Dehairs, Frank (2013): Late summer particulate organic carbon export and twilight zone remineralisation in the Atlantic sector of the Southern Ocean. Biogeosciences, 10(2), 803-820, https://doi.org/10.5194/bg-10-803-2013
Puigcorbé, Viena; Roca-Martí, Montserrat; Masqué, Pere; Benitez-Nelson, Claudia R; Rutgers van der Loeff, Michiel M; Bracher, Astrid; Moreau, Sebastien (2017): Latitudinal distributions of particulate carbon export across the North Western Atlantic Ocean. Deep Sea Research Part I: Oceanographic Research Papers, 129, 116-130, https://doi.org/10.1016/j.dsr.2017.08.016
Puigcorbé, Viena; Roca-Martí, Montserrat; Masqué, Pere; Benitez-Nelson, Claudia R; Rutgers van der Loeff, Michiel M; Laglera, Luis Miguel; Bracher, Astrid; Cheah, Wee; Strass, Volker H; Hoppema, Mario; Santos-Echeandía, Juan; Hunt, Brian P V; Pakhomov, Evgeny A; Klaas, Christine (2017): Particulate organic carbon export across the Antarctic Circumpolar Current at 10°E: Differences between north and south of the Antarctic Polar Front. Deep Sea Research Part II: Topical Studies in Oceanography, 138, 68-101, https://doi.org/10.1016/j.dsr2.2016.05.016
Rosengard, Sarah Z; Lam, Phoebe J; Balch, William M; Auro, M E; Pike, Steven M; Drapeau, Dave T; Bowler, Bruce C (2015): Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt. Biogeosciences, 12(13), 3953-3971, https://doi.org/10.5194/bg-12-3953-2015
Stewart, Gillian M; Bradley Moran, S; Lomas, Michael W (2010): Seasonal POC fluxes at BATS estimated from 210Po deficits. Deep Sea Research Part I: Oceanographic Research Papers, 57(1), 113-124, https://doi.org/10.1016/j.dsr.2009.09.007
Stewart, Gillian M; Moran, S Bradley; Lomas, Michael W; Kelly, Roger P (2011): Direct comparison of 210Po, 234Th and POC particle-size distributions and export fluxes at the Bermuda Atlantic Time-series Study (BATS) site. Journal of Environmental Radioactivity, 102(5), 479-489, https://doi.org/10.1016/j.jenvrad.2010.09.011
Stukel, Michael R; Schofield, Oscar M E; Ducklow, Hugh W (2022): Seasonal variability in carbon:234thorium ratios of suspended and sinking particles in coastal Antarctic waters: Field data and modeling synthesis. Deep Sea Research Part I: Oceanographic Research Papers, 184, 103764, https://doi.org/10.1016/j.dsr.2022.103764
Subha Anand, S; Rengarajan, Ramabadran; Sarma, Vedula V S S (2018): 234Th-Based Carbon Export Flux Along the Indian GEOTRACES GI02 Section in the Arabian Sea and the Indian Ocean. Global Biogeochemical Cycles, 32(3), 417-436, https://doi.org/10.1002/2017GB005847
Subha Anand, S; Rengarajan, Ramabadran; Sarma, Vedula V S S; Sudheer, A K; Bhushan, R; Singh, Sunil Kumar (2017): Spatial variability of upper ocean POC export in the Bay of Bengal and the Indian Ocean determined using particle-reactive 234Th. Journal of Geophysical Research: Oceans, 122(5), 3753-3770, https://doi.org/10.1002/2016JC012639
Subha Anand, S; Rengarajan, Ramabadran; Shenoy, Damodar; Gauns, Mangesh; Naqvi, Syed Wajih Ahmad (2018): POC export fluxes in the Arabian Sea and the Bay of Bengal: A simultaneous 234Th/238U and 210Po/210Pb study. Marine Chemistry, 198, 70-87, https://doi.org/10.1016/j.marchem.2017.11.005
Tang, Yi; Lemaitre, Nolwenn; Castrillejo, Maxi; Roca-Martí, Montserrat; Masqué, Pere; Stewart, Gillian M (2019): The export flux of particulate organic carbon derived from 210 Po∕ 210 Pb disequilibria along the North Atlantic GEOTRACES GA01 transect: GEOVIDE cruise. Biogeosciences, 16(2), 309-327, https://doi.org/10.5194/bg-16-309-2019
Yu, Wen; He, Jianhua; Li, Y; Lin, Wenyi; Chen, Liqi (2012): Particulate organic carbon export fluxes and validation of steady state model of 234Th export in the Chukchi Sea. Deep Sea Research Part II: Topical Studies in Oceanography, 81-84, 63-71, https://doi.org/10.1016/j.dsr2.2012.03.003
Documentation:
Readme: Global particulate organic carbon flux derived from Th-234: 13 ocean regions, 3 export depths. read_me.txt
Funding:
Complementary Plan for R&D and Innovation in Marine Sciences (THINKINAZUL), grant/award no. PCM_00063: DEveloping rePOsitories for CARBON export quantification in the ocean
Coverage:
Median Latitude: 15.201324 * Median Longitude: -71.010912 * South-bound Latitude: -64.770000 * West-bound Longitude: -160.000000 * North-bound Latitude: 78.650000 * East-bound Longitude: 89.050000
Date/Time Start: 1992-03-11T00:00:00 * Date/Time End: 2018-09-04T00:00:00
Minimum DEPTH, water: -999 m * Maximum DEPTH, water: 251 m
Parameter(s):
License:
Creative Commons Attribution 4.0 International (CC-BY-4.0) (License comes into effect after moratorium ends)
Status:
Curation Level: Basic curation (CurationLevelB)
Size:
3261 data points
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