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1. Isotopes illustrate vertical transport of anthropogenic Pb by reversible scavenging within Pacific Ocean particle veils

   https://doi.org/10.1073/pnas.2219688120  

   Lanning, Nathan T.; Jiang, Shuo; Amaral, Vinicius J.; Mateos, Katherine; Steffen, Janelle M.; Lam, Phoebe J.; Boyle, Edward A.; Fitzsimmons, Jessica N. (June 2023, Proceedings of the National Academy of Sciences)

   Reversible scavenging, the oceanographic process by which dissolved metals exchange onto and off sinking particles and are thereby transported to deeper depths, has been well established for the metal thorium for decades. Reversible scavenging both deepens the elemental distribution of adsorptive elements and shortens their oceanic residence times in the ocean compared to nonadsorptive metals, and scavenging ultimately removes elements from the ocean via sedimentation. Thus, it is important to understand which metals undergo reversible scavenging and under what conditions. Recently, reversible scavenging has been invoked in global biogeochemical models of a range of metals including lead, iron, copper, and zinc to fit modeled data to observations of oceanic dissolved metal distributions. Nonetheless, the effects of reversible scavenging remain difficult to visualize in ocean sections of dissolved metals and to distinguish from other processes such as biological regeneration. Here, we show that particle-rich “veils” descending from high-productivity zones in the equatorial and North Pacific provide idealized illustrations of reversible scavenging of dissolved lead (Pb). A meridional section of dissolved Pb isotope ratios across the central Pacific shows that where particle concentrations are sufficiently high, such as within particle veils, vertical transport of anthropogenic surface–dissolved Pb isotope ratios toward the deep ocean is manifested as columnar isotope anomalies. Modeling of this effect shows that reversible scavenging within particle-rich waters allows anthropogenic Pb isotope ratios from the surface to penetrate ancient deep waters on timescales sufficiently rapid to overcome horizontal mixing of deep water Pb isotope ratios along abyssal isopycnals. 

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2. A global synthesis of high-resolution stable isotope data from benthic foraminifera of the last deglaciation

   https://doi.org/10.5281/zenodo.7502756  

   Muglia, Juan; Mulitza, Stefan; Repschläger, Janne; Schmittner, Andreas; Lembke-Jene, Lester; Mix, Alan; Saraswat, Rajeev; Sikes, Elizabeth; Waelbroeck, Claire; Gottschalk, Julia; et al (January 2023, Zenodo)

   In paleoceanography, carbon and oxygen stable isotope ratios from benthic foraminifera are used as tracers of physical and biogeochemical properties of the deep ocean. We present the first version of the Ocean Carbon Cycling working group database,  of stable isotope ratios of oxygen and carbon from benthic foraminifera from deep ocean sediment cores from the Last Glacial Maximum (LGM, 23-20 ky before present (BP)) to the Holocene (<10 ky BP) with a particular focus on the early last deglaciation (20-15 ky BP). It includes 287 globally distributed coring sites, with metadata, isotopic and chronostratigraphic information, and age models. A quality check was performed for all data and age models. Sites with at least millennial resolution were preferred, because the main goal is to resolve ocean changes associated with the last deglaciation on at least millennial timescales. Software tools were produced to access and analyze the data, and are included with this publication. Deep water mass structure as well as differences between the early deglaciation and LGM are captured by the data in the compilation, even though its coverage is still sparse in many ocean regions. We find high correlations among time series calculated with different age models at sites that allow such analysis. The database provides a useful dynamical approach to map physical and biogeochemical changes of the ocean throughout the last deglaciation.</p> Custom python scripts to read and analyze the data base may be found in https://github.com/juanmuglia/OC3-python-scripts and in OC3-python-scripts.zip in this repository. plots_d13c.pdf and plots_d18o.pdf contain time series for all sites and available age models. 

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3. A global ocean dissolved organic phosphorus concentration database (DOPv2021)

   https://doi.org/10.1038/s41597-022-01873-7  

   Liang, Zhou; McCabe, Kelly; Fawcett, Sarah E.; Forrer, Heather J.; Hashihama, Fuminori; Jeandel, Catherine; Marconi, Dario; Planquette, Hélène; Saito, Mak A.; Sohm, Jill A.; et al (December 2022, Scientific Data)

   Abstract Dissolved organic phosphorus (DOP) concentration distributions in the global surface ocean inform our understanding of marine biogeochemical processes such as nitrogen fixation and primary production. The spatial distribution of DOP concentrations in the surface ocean reflect production by primary producers and consumption as an organic nutrient by phytoplankton including diazotrophs and other microbes, as well as other loss processes such as photolysis. Compared to dissolved organic carbon and nitrogen, however, relatively few marine DOP concentration measurements have been made, largely due to the lack of automated analysis techniques. Here we present a database of marine DOP concentration measurements (DOPv2021) that includes new (n = 730) and previously published (n = 3140) observations made over the last ~30 years (1990–2021), including 1751 observations in the upper 50 m. This dataset encompasses observations from all major ocean basins including the poorly represented Indian, South Pacific, and Southern Oceans and provides insight into spatial distributions of DOP in the ocean. It is also valuable for researchers who work on marine primary production and nitrogen fixation. 

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4. Using Excess ³ He to Estimate Southern Ocean Upwelling Time Scales

   https://doi.org/10.1029/2020GL087266  

   Jenkins, William J. (August 2020, Geophysical Research Letters)

   Abstract Using a recently compiled global marine data set of dissolved helium isotopes and helium and neon concentrations, we make an estimate of the inventory of hydrothermal³He in the Southern Ocean to be 4.9 ± 0.6 × 10⁴ moles. Under the assumption that the bulk of the hydrothermally sourced³He is upwelled there, we use recent estimates of the global hydrothermal³He flux to determine ane‐folding residence time of 99 ± 18 years, depending on assumptions of water mass and upwelling boundaries. Our estimate is within the broad range of values obtained from recent Southern Ocean circulation models. 

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5. Coastal Ocean Data Analysis Product in North America (CODAP-NA) – an internally consistent data product for discrete inorganic carbon, oxygen, and nutrients on the North American ocean margins

   https://doi.org/10.5194/essd-13-2777-2021  

   Jiang, Li-Qing; Feely, Richard A.; Wanninkhof, Rik; Greeley, Dana; Barbero, Leticia; Alin, Simone; Carter, Brendan R.; Pierrot, Denis; Featherstone, Charles; Hooper, James; et al (January 2021, Earth System Science Data)

   null (Ed.)

   Abstract. Internally consistent, quality-controlled (QC) data products play animportant role in promoting regional-to-global research efforts tounderstand societal vulnerabilities to ocean acidification (OA). However,there are currently no such data products for the coastal ocean, where mostof the OA-susceptible commercial and recreational fisheries and aquacultureindustries are located. In this collaborative effort, we compiled, quality-controlled, and synthesized 2 decades of discrete measurements ofinorganic carbon system parameters, oxygen, and nutrient chemistry data fromthe North American continental shelves to generate a data product calledthe Coastal Ocean Data Analysis Product in North America (CODAP-NA). Thereare few deep-water (> 1500 m) sampling locations in the currentdata product. As a result, crossover analyses, which rely on comparisonsbetween measurements on different cruises in the stable deep ocean, couldnot form the basis for cruise-to-cruise adjustments. For this reason, carewas taken in the selection of data sets to include in this initial releaseof CODAP-NA, and only data sets from laboratories with known qualityassurance practices were included. New consistency checks and outlierdetections were used to QC the data. Future releases of this CODAP-NAproduct will use this core data product as the basis for cruise-to-cruisecomparisons. We worked closely with the investigators who collected andmeasured these data during the QC process. This version (v2021) of theCODAP-NA is comprised of 3391 oceanographic profiles from 61 researchcruises covering all continental shelves of North America, from Alaska toMexico in the west and from Canada to the Caribbean in the east. Data for 14variables (temperature; salinity; dissolved oxygen content; dissolvedinorganic carbon content; total alkalinity; pH on total scale; carbonateion content; fugacity of carbon dioxide; and substance contents of silicate,phosphate, nitrate, nitrite, nitrate plus nitrite, and ammonium) have beensubjected to extensive QC. CODAP-NA is available as a merged data product(Excel, CSV, MATLAB, and NetCDF; https://doi.org/10.25921/531n-c230,https://www.ncei.noaa.gov/data/oceans/ncei/ocads/metadata/0219960.html, last access: 15 May 2021)(Jiang et al., 2021a). The original cruise data have also been updated withdata providers' consent and summarized in a table with links to NOAA'sNational Centers for Environmental Information (NCEI) archives(https://www.ncei.noaa.gov/access/ocean-acidification-data-stewardship-oads/synthesis/NAcruises.html). 

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