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A Three-Dimensional Mapping of the Ocean Based on Environmental Data

Abstract.

"The existence, sources, distribution, circulation, and physicochemical nature of macroscale oceanic water bodies have long been a focus of oceanographic inquiry. Building on that work, this paper describes an objectively derived and globally comprehensive set of 37 distinct volumetric region units, called ecological marine units (EMUs). They are constructed on a regularly spaced ocean point-mesh grid, from sea surface to seafloor, and attributed with data from the 2013 World Ocean Atlas version 2. The point attribute data are the means of the decadal averages from a 57-year climatology of six physical and chemical environment parameters (temperature, salinity, dissolved oxygen, nitrate, phosphate, and silicate). [...]"

Source: Oceanography
Authors: Roger G. Sayre
DOI: 10.5670/oceanog.2017.116

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Climate and anthropogenic controls of coastal deoxygenation on interannual to centennial timescales

Abstract.

"Understanding dissolved oxygen variability in the ocean is limited by the short duration of direct measurements, however sedimentary oxidation-reduction reactions can provide context for modern observations. Here we use bulk sediment redox-sensitive metal enrichment factors (MoEF, ReEF, and UEF) and scanning X-ray fluorescence (XRF) records to examine annual-scale sedimentary oxygen concentrations in the Santa Barbara Basin from the Industrial Revolution (AD ~1850) to present. [...]"

Source: Geophysical Research Letters
Authors: Yi Wang, Ingrid Hendy, Tiffany J. Napier
DOI: 10.1002/2017GL075443

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Hydrography in the Mediterranean Sea during a cruise with RV Tethys 2 in May 2015

Abstract.

"We report on data from an oceanographic cruise, covering western, central and eastern parts of the Mediterranean Sea, on the French research vessel Tethys 2 in May 2015. This cruise was fully dedicated to the maintenance and the metrological verification of a biogeochemical observing system based on a fleet of BGC-Argo floats. During the cruise, a comprehensive dataset of parameters sensed by the autonomous network was collected. [...]"

Source: Earth System Science Data (unter review)
Authors: Vincent Taillandier et al.
DOI: 10.5194/essd-2017-119

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Temporal variation in pelagic food chain length in response to environmental change

Abstract.

"Climate variability alters nitrogen cycling, primary productivity, and dissolved oxygen concentration in marine ecosystems. We examined the role of this variability (as measured by six variables) on food chain length (FCL) in the California Current (CC) by reconstructing a time series of amino acid–specific δ15N values derived from common dolphins, an apex pelagic predator, and using two FCL proxies.  [...]"

Source: Science Advances
Authors: Rocio I. Ruiz-Cooley et al.
DOI: 10.1126/sciadv.1701140

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Oceanic uptake of oxygen during deep convection events through diffusive and bubble mediated gas exchange

Abstract.

"The concentration of dissolved oxygen (O2) plays fundamental roles in diverse chemical and biological processes throughout the oceans. The balance between the physical supply and the biological consumption controls the O2 level of the interior ocean, and the O2 supply to the deep waters can only occur through deep convection in the polar oceans. [...]"

Source: Global Biogeochemical Cycles
Authors: Daoxun Sun, Takamitsu Ito, Annalisa Bracco
DOI: 10.1002/2017GB005716

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Sound physiological knowledge and principles in modeling shrinking of fishes under climate change

Abstract.

"One of the main expected responses of marine fishes to ocean warming is decrease in body size, as supported by evidence from empirical data and theoretical modeling. The theoretical underpinning for fish shrinking is that the oxygen supply to large fish size cannot be met by their gills, whose surface area cannot keep up with the oxygen demand by their three-dimensional bodies. [...]"

Source: Global Change Biology
Authors: Daniel Pauly, William W. L. Cheung
DOI: 10.1111/gcb.13831

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Ecophenotypic responses of benthic foraminifera to oxygen availability along an oxygen gradient in the California Borderland

Abstract.

"Spatial variation in environmental conditions can elicit predictable size and morphological responses in marine organisms through influences on physiology. Thus, spatial and temporal variation in marine organism size and shape are often used to infer paleoenvironmental conditions, such as dissolved oxygen concentrations. Benthic foraminifera commonly serve as a tool for reconstructing past ocean oxygen levels. [...]" 

Source: marine ecology
Authors: Caitlin R. Keating-Bitonti, Jonathan L. Payne
DOI: 10.1111/maec.12430

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Metabolic Roles of Uncultivated Bacterioplankton Lineages in the Northern Gulf of Mexico “Dead Zone”

Abstract.

"Marine regions that have seasonal to long-term low dissolved oxygen (DO) concentrations, sometimes called “dead zones,” are increasing in number and severity around the globe with deleterious effects on ecology and economics. One of the largest of these coastal dead zones occurs on the continental shelf of the northern Gulf of Mexico (nGOM), which results from eutrophication-enhanced bacterioplankton respiration and strong seasonal stratification. [...]"

Source: mBio
Authors: J. Cameron Thrash et al.
DOI: 10.1128/mBio.01017-17

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Intense oceanic uptake of oxygen during 2014–2015 winter convection in the Labrador Sea

Abstract.

"Measurements of near-surface oxygen (O2) concentrations and mixed layer depth from the K1 mooring in the central Labrador Sea are used to calculate the change in column-integrated (0–1700 m) O2 content over the deep convection winter 2014/2015. During the mixed layer deepening period, November 2014 to April 2015, the oxygen content increased by 24.3 ± 3.4 mol m−2, 40% higher than previous results from winters with weaker convection. By estimating the contribution of respiration and lateral transport on the oxygen budget, the cumulative air-sea gas exchange is derived. [...]"

Source: Geophysical Research Letters
Authors: Jannes Koelling, Douglas W. R. Wallace, Uwe Send, Johannes Karstensen
DOI: 10.1002/2017GL073933

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Taking a deep breath? Scientists measure unusually high oxygen uptake in the Labrador Sea

"The Labrador Sea in the North Atlantic is one of the few areas in the world ocean where cold, saline seawater sinks to large depths and forms deep water. This convection process also transports oxygen into the deep sea. A team of scientists from Scripps Institution of Oceanography (San Diego, California), Dalhousie University (Halifax, Canada) and GEOMAR Helmholtz Centre for Ocean Research Kiel have now published the analysis of data obtained from the mooring K1 in the international scientific journal Geophysical Research Letters. [...]"

Source: phys.org

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