How fast are elements sinking in the ocean?

Posted by mmaheigan 
· Tuesday, March 5th, 2019 

The sinking of elements in the ocean influences many important processes such as deep ocean carbon storage and the availability of trace metals for phytoplankton. Previously, quantification of this sinking flux has been done using sediment trap deployments or tracer measurements of a particle-reactive radioisotope. Since sediment traps and each particular radioisotope each have caveats in how they quantify sinking flux, sinking particulate flux measurements, especially trace metal fluxes, are especially sparse, with relatively large uncertainties. For the first time ever, in the U.S. GEOTRACES North Atlantic campaign (GA03), four types of radioisotope data (thorium-234, polonium-210, thorium-228 and thorium-230) were measured, along with a periodic table’s worth of particulate elements that can be used to quantify sinking fluxes at locations with prior sediment trap studies, including the Ocean Flux Program (OFP), for comparison.

Sinking flux estimates of particulate organic carbon (POC) and particulate iron (pFe) derived using different methods, including the different radionuclides labelled and sediment traps from oceanic sites near Bermuda. These include the Bermuda-Atlantic Time-series site (BATS), the Ocean Flux Program site (OFP), and the Bermuda Rise (BaRFlux site). The GA03 and BaRFlux data represent observations from 2012 and 2013. The triangles and stars represent data from throughout the time-series observations of those sites.

In a new study published in Global Biogeochemical Cycles, a team of collaborators synthesized all of the radioisotope and particle composition measurements from the GA03 cruise, as well as results from a nearby study called BaRFlux, to constrain sinking fluxes of carbon and eight trace elements (P, Cd, Co, Cu, Mn, Al, Fe and thorium-232) throughout the North Atlantic Ocean. The five different methods for constraining flux (sediment traps plus the four radioisotope methods) agree encouragingly well given the independent uncertainties associated with each method. Additionally, since the four radioisotopes have a range in half-lives from days to thousands of years, the different methods can reconstruct particle fluxes throughout the water column, from the dynamic bloom-and-bust-like changes near the surface to the relatively slow, long-term sinking into the abyssal ocean. These fluxes will improve the understanding of the global budgets of carbon and trace elements. This study would not have been possible without the support of OCB and GEOTRACES who co-funded a synthesis workshop on biogeochemical cycling of trace elements at the Lamont-Doherty Earth Observatory in summer 2016.

Also see Eos highlight on this article

Authors:
Christopher T. Hayes (University of Southern Mississippi)
Erin E. Black (Woods Hole Oceanographic Institution, now at Dalhousie University)
Robert F. Anderson (Lamont-Doherty Earth Observatory of Columbia University)
Mark Baskaran (Wayne State University)
Ken O. Buesseler (Woods Hole Oceanographic Institution)
Matthew A. Charette (Woods Hole Oceanographic Institution)
Hai Cheng (Xi’an Jiaotong University and University of Minnesota)
Kirk Cochran (Stony Brook University)
Lawrence Edwards (University of Minnesota)
Patrick Fitzgerald (Stony Brook University)
Phoebe J. Lam (University of California Santa Cruz
Yanbin Lu (Earth Observatory of Singapore)
Stephanie O. Morris (Woods Hole Oceanographic institution)
Daniel C. Ohnemus (Bigelow Laboratory for Ocean Sciences, now at Skidaway Institute of Oceanography)
Frank J. Pavia (Lamont-Doherty Earth Observatory of Columbia University)
Gillian Stewart (Queens College, City University of New York)
Yi Tang (Queens College, City University of New York)

Filter by Keyword

abundance acidification additionality advection africa air-sea air-sea interactions algae alkalinity allometry ammonium AMO AMOC anoxic Antarctic Antarctica anthro impacts anthropogenic carbon anthropogenic impacts appendicularia aquaculture aquatic continuum aragonite saturation arctic Argo argon arsenic artificial seawater Atlantic atmospheric CO2 atmospheric nitrogen deposition authigenic carbonates autonomous platforms bacteria bathypelagic BATS BCG Argo benthic bgc argo bio-go-ship bio-optical bioavailability biogeochemical cycles biogeochemical models biogeochemistry Biological Essential Ocean Variables biological pump biophysics bloom blue carbon bottom water boundary layer buffer capacity C14 CaCO3 calcification calcite carbon carbon-climate feedback carbon-sulfur coupling carbonate carbonate system carbon budget carbon cycle carbon dioxide carbon export carbon fluxes carbon sequestration carbon storage Caribbean CCA CCS changing marine chemistry changing marine ecosystems changing marine environments changing ocean chemistry chemical oceanographic data chemical speciation chemoautotroph chesapeake bay chl a chlorophyll circulation climate change climate changes climate variability CO2 coastal and estuarine coastal darkening coastal ocean cobalt Coccolithophores commercial community composition conservation cooling effect copepod copepods coral reefs CTD currents cyclone daily cycles data data access data assimilation database data management data product Data standards DCM dead zone decadal trends decomposers decomposition deep convection deep ocean deep sea coral deoxygenation depth diatoms DIC diel migration diffusion dimethylsulfide dinoflagellate dinoflagellates discrete measurements distribution DOC DOM domoic acid DOP dust DVM ecology economics ecosystem management ecosystems eddy Education EEZ Ekman transport emissions ENSO enzyme equatorial current equatorial regions ESM estuarine and coastal carbon fluxes estuary euphotic zone eutrophication evolution export export fluxes export production EXPORTS extreme events faecal pellets fecal pellets filter feeders filtration rates fire fish Fish carbon fisheries fishing floats fluid dynamics fluorescence food webs forage fish forams freshening freshwater frontal zone functional role future oceans gelatinous zooplankton geochemistry geoengineering geologic time GEOTRACES glaciers gliders global carbon budget global ocean global warming go-ship grazing greenhouse gas Greenland ground truthing groundwater Gulf of Maine Gulf of Mexico Gulf Stream gyre harmful algal bloom high latitude human food human impact human well-being hurricane hydrogen hydrothermal hypoxia ice age ice cores ice cover industrial onset inland waters in situ inverse circulation ions iron iron fertilization isotopes jellies katabatic winds kelvin waves krill kuroshio lab vs field land-ocean continuum larvaceans lateral transport LGM lidar ligands light light attenuation lipids machine learning mangroves marine carbon cycle marine heatwave marine particles marine snowfall marshes mCDR Mediterranean meltwater mesopelagic mesoscale mesoscale processes metagenome metals methane methods microbes microlayer microorganisms microplankton microscale microzooplankton midwater mitigation mixed layer mixed layers mixing mixotrophs mixotrophy model modeling model validation mode water molecular diffusion MPT MRV multi-decade n2o NAAMES NASA NCP nearshore net community production net primary productivity new ocean state new technology Niskin bottle nitrate nitrogen nitrogen cycle nitrogen fixation nitrous oxide north atlantic north pacific nuclear war nutricline nutrient budget nutrient cycles nutrient cycling nutrient limitation nutrients OA ocean-atmosphere ocean acidification ocean acidification data ocean alkalinity enhancement ocean carbon storage and uptake ocean carbon uptake and storage ocean color ocean modeling ocean observatories ocean warming ODZ oligotrophic omics OMZ open ocean optics organic particles oscillation outwelling overturning circulation oxygen pacific paleoceanography PAR parameter optimization parasite particle flux particles partnerships pCO2 PDO peat pelagic PETM pH phenology phosphate phosphorus photosynthesis physical processes physiology phytoplankton PIC piezophilic piezotolerant plankton POC polar polar regions policy pollutants precipitation predation predator-prey prediction pressure primary productivity Prochlorococcus prokaryotes proteins pteropods pycnocline radioisotopes remineralization remote sensing repeat hydrography residence time resource management respiration resuspension rivers rocky shore Rossby waves Ross Sea ROV salinity salt marsh satellite scale seafloor seagrass sea ice sea level rise seasonal seasonality seasonal patterns seasonal trends sea spray seawater collection seaweed secchi sediments sensors sequestration shelf ocean shelf system shells ship-based observations shorelines silica silicate silicon cycle sinking sinking particles size SOCCOM soil carbon southern ocean south pacific spatial covariations speciation SST state estimation stoichiometry subduction submesoscale subpolar subtropical sulfate surf surface surface ocean Synechococcus technology teleconnections temperate temperature temporal covariations thermocline thermodynamics thermohaline thorium tidal time-series time of emergence titration top predators total alkalinity trace elements trace metals trait-based transfer efficiency transient features Tris trophic transfer tropical turbulence twilight zone upper ocean upper water column upwelling US CLIVAR validation velocity gradient ventilation vertical flux vertical migration vertical transport volcano warming water clarity water mass water quality waves weathering western boundary currents wetlands winter mixing zooplankton

Copyright © 2024 - OCB Project Office, Woods Hole Oceanographic Institution, 266 Woods Hole Rd, MS #25, Woods Hole, MA 02543 USA Phone: 508-289-2838  •  Fax: 508-457-2193  •  Email: ocb_news@us-ocb.org

link to nsflink to noaalink to WHOI

Funding for the Ocean Carbon & Biogeochemistry Project Office is provided by the National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA). The OCB Project Office is housed at the Woods Hole Oceanographic Institution.