Constraint on net primary productivity of the global ocean by Argo oxygen measurements
"The biological transformation of dissolved inorganic carbon to organic carbon during photosynthesis in the ocean, marine primary production, is a fundamental driver of biogeochemical cycling, ocean health and Earth’s climate system. The organic matter created supports oceanic food webs, including fisheries, and is an essential control on atmospheric carbon dioxide levels. Marine primary productivity is sensitive to changes due to climate forcing, but observing the response at the global scale[...]"
Source: Nature Geoscience
Authors: Kenneth S. Johnson et al.
Transferring Complex Scientific Knowledge to Useable Products for Society: The Role of the Global Integrated Ocean Assessment and Challenges in the
Effective Delivery of Ocean Knowledge
"The ocean provides essential services to human wellbeing through climate regulation, provision of food, energy and livelihoods, protection of communities and nurturing of social and cultural values. Yet despite the ocean’s key role for all life, it is failing as a result of unsustainable human practices. The first global integrated assessment of the marine environment, produced by the United Nations under The Regular Process for Global Reporting and Assessment of the State of the Marine Environment, including Socioeconomic Aspects (the World Ocean Assessment), identified an overall decline in ocean health. The second assessment, launched in April 2021, although recognising some bright spots and improvements, stresses ongoing decline in the ocean[...]"
Authors: Karen Evans et al.
Oxygen loss in fjords, coastal areas, and open ocean systems
"Loss of oxygen and expansion of oxygen depleted environments have been witnessed in both coastal and open-ocean systems since the middle of the 20th century, and ocean modelling predicts continuing decease by the year 2100. Oxygen depletion occurs thus during the same time epoch as global warming. Increased knowledge on how and why oxygen varies in space and time shapes the biogeochemical and ecological structure of marine systems and will be needed for future predictions of marine productivity. In coastal systems deoxygenation is also linked to human activities that lead to increased loadings of nutrients and organic matter, and to regional effects of climate induced changes in wind and precipitation patterns[...]"
Source: BJERKNES CENTRE
Authors: Anne Gro Vea Salvanes et al.
Low oxygen levels can help to prevent the detrimental effect of acute warming on mitochondrial efficiency in fish
"Aerobic metabolism of aquatic ectotherms is highly sensitive to fluctuating climates. Many mitochondrial traits exhibit phenotypic plasticity in response to acute variations in temperature and oxygen availability. These responses are critical for understanding the effects of environmental variations on aquatic ectotherms' performance. Using the European seabass, Dicentrarchus labrax, we determined the effects of acute warming and deoxygenation in vitro on mitochondrial respiratory capacities and mitochondrial[...]"
Source: The Royal Society Publishing
Authors: Elisa Thoral et al.
More than 1000 rivers account for 80% of global riverine plastic emissions into the ocean
"Plastic waste increasingly accumulates in the marine environment, but data on the distribution and quantification of riverine sources required for development of effective mitigation are limited. Our model approach includes geographically distributed data on plastic waste, land use, wind, precipitation, and rivers and calculates the probability for plastic waste to reach a river and subsequently the ocean. This probabilistic approach highlights regions that are likely to emit plastic into the ocean. We calibrated our model using recent field observations[...]".
Source: Science Advances
Authors: LOURENS J. J. MEIJER et al.
The soundscape of the Anthropocene ocean
"Oceans have become substantially noisier since the Industrial Revolution. Shipping, resource exploration, and infrastructure development have increased the anthrophony (sounds generated by human activities), whereas the biophony (sounds of biological origin) has been reduced by hunting, fishing, and habitat degradation. Climate change is affecting geophony (abiotic, natural sounds). Existing evidence shows that anthrophony affects marine animals[...]".
Authors: Carlos M. Duarte et al.
System controls of coastal and open ocean oxygen depletion
"The epoch of the Anthropocene, a period during which human activity has been the dominant influence on climate and the environment, has witnessed a decline in oxygen concentrations and an expansion of oxygen-depleted environments in both coastal and open ocean systems since the middle of the 20th century. This paper provides a review of system-specific drivers of low oxygen in a range of case studies representing marine systems in the open ocean, on continental shelves, in enclosed seas[...]".
Source: Science Direct
Authors: Grant C. Pitcher
High spatial resolution global ocean metagenomes from Bio-GO-SHIP repeat hydrography transects
"Detailed descriptions of microbial communities have lagged far behind physical and chemical measurements in the marine environment. Here, we present 971 globally distributed surface ocean metagenomes collected at high spatio-temporal resolution. Our low-cost metagenomic sequencing protocol produced 3.65 terabases of data, where the median number of base pairs per sample was 3.41 billion. The median distance between sampling stations was 26 km[...]"
Source: Scientific Data
Authors: Alyse A. Larkin et al
Reconstructing the Preindustrial Coastal Carbon Cycle Through a Global Ocean Circulation Model: Was the Global Continental Shelf Already Both Autotrop
"The contribution of continental shelves to the marine carbon cycle is still poorly understood. Their preindustrial state is, for one, essentially unknown, which strongly limits the quantitative assessment of their anthropogenic perturbation. To date, approaches developed to investigate and quantify carbon fluxes on continental shelves have strongly simplified their physical and biogeochemical features. In this study, we enhance the global ocean biogeochemistry model HAMburg Ocean Carbon Cycle by[...]"
Source: AGU- Advancing Earth and Space Science
Authors: Fabrice Lacroix et al.
Impacts of hypoxic events surpass those of future ocean warming and acidification
"Over the past decades, three major challenges to marine life have emerged as a consequence of anthropogenic emissions: ocean warming, acidification and oxygen loss. While most experimental research has targeted the first two stressors, the last remains comparatively neglected. Here, we implemented sequential hierarchical mixed-model meta-analyses (721 control–treatment comparisons) to compare the impacts of oxygen conditions associated with the current and continuously intensifying hypoxic events (1–3.5 O2 mg l−1) with those experimentally yielded by ocean warming (+4 °C) and acidification (−0.4 units) conditions[...]"
Source: Nature Ecology & Evolution
Authors: Eduardo Sampaio et al.