Abstract.

"El Niño events, in particular the eastern Pacific type, have a tremendous impact on the marine ecosystem and climate conditions in the eastern South Pacific. During such events, the accumulation of anomalously warm waters along the coast favors intense rainfall. The upwelling of nutrient-replete waters is stopped and the marine ecosystem is strongly impacted. These events are generally associated with positive surface temperature anomalies in the central and eastern equatorial Pacific. [...]"

Source: Frontiers in Marine Science
Authors: Vincent Echevin et al.
DOI: 10.3389/fmars.2018.00367

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Abstract.

"The ocean is the main source of thermal inertia in the climate system. During recent decades, ocean heat uptake has been quantified by using hydrographic temperature measurements and data from the Argo float program, which expanded its coverage after 2007. However, these estimates all use the same imperfect ocean dataset and share additional uncertainties resulting from sparse coverage, especially before 2007.  [...]"

Source: Nature
Authors: L. Resplandy et al.
DOI: 10.1038/s41586-018-0651-8

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"In den tropischen und subtropischen Meeren existieren in mittleren Tiefen riesige sauerstoffarme Zonen. Im Zuge des Klimawandels dehnen sie sich immer stärker aus. Auch in Küstenregionen entstehen durch Stickstoffbelastung aus der Landwirtschaft lebensfeindliche Zonen ohne Sauerstoff – mit verheerenden Folgen für das marine Ökosystem [...]"

Source: Spektrum.de

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Abstract.

"Beyond key ecological services, marine resources are crucial for human food security and socio-economical sustainability. Among them, shellfish aquaculture and fishing are of primary importance but become more vulnerable under anthropogenic pressure, as evidenced by reported mass mortality events linked to global changes such as ocean warming and acidification, chemical contamination, and diseases. Understanding climate-related risks is a vital objective for conservation strategies, ecosystems management and human health.  [...]"

Source: Environmental Research Letters
Authors: Yoann Thomas et al.
DOI: 10.1088/1748-9326/aae254

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The german Internet and TV channel HYPERRAUM.TV published two reports in collaboration with the SFB754 experts Martin Visbeck and Andreas Oschlies.

German speaking users may find the videos online by using one of the two links:

Report 1: Fische in Atemnot

Report 2: Sauerstoff-Transporte

Abstract.

"Oxygen loss in the ocean, termed deoxygenation, is a major consequence of climate change and is exacerbated by other aspects of global change. An average global loss of 2% or more has been recorded in the open ocean over the past 50–100 years, but with greater oxygen declines in intermediate waters (100–600 m) of the North Pacific, the East Pacific, tropical waters, and the Southern Ocean. Although ocean warming contributions to oxygen declines through a reduction in oxygen solubility and stratification effects on ventilation are reasonably well understood, it has been a major challenge to identify drivers and modifying factors that explain different regional patterns, especially in the tropical oceans. [...]"

Source: Annual Review of Marine Science
Author: L. Levin
DOI: 10.1146/annurev-marine-121916-063359

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"An IMAS-led voyage on the Marine National Facility research vessel Investigator today sailed from Hobart with scientists aiming to solve a Southern Ocean puzzle with important ramifications for the global climate.

The researchers will survey a ‘standing meander’ south of Tasmania that they hope will help them to understand why the east-flowing Antarctic Circumpolar Current (ACC) has remained constant despite westerly winds strengthening by 20% over the last two decades. [...]"

Source: IMAS

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Abstract.

"The Smithian-Spathian boundary (SSB) was an interval characterized by a major global carbon cycle perturbation, climatic cooling from a middle/late Smithian boundary hyperthermal condition, and a major setback in the recovery of marine necto-pelagic faunas from the end-Permian mass extinction. Although the SSB has been linked to changes in oceanic redox conditions, key aspects of this redox variation (e.g., duration, extent, and triggering mechanisms) and its relationship to coeval climatic and biotic changes remain unresolved. [...]"

Source: Earth-Science Reviews
Authors: Feifei Zhang et al.
DOI: 10.1016/j.earscirev.2018.10.012

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Abstract.

"Blue mussel (Mytilus edulis) produce byssal threads to anchor themselves to the substrate. These threads are always exposed to the surrounding environmental conditions. Understanding how environmental pH affects these threads is crucial in understanding how climate change can affect mussels. This work examines three factors (load at failure, thread extensibility, and total thread counts) that indicate the performance of byssal threads as well as condition index to assess impacts on the physiological condition of mussels held in artificial seawater acidified by the addition of CO₂. [...]"

Source: PLOS ONE
Authors: Grant Dickey et al.
DOI: 10.1371/journal.pone.0205908

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Abstract.

"Increased storage of carbon in the oceans has been proposed as a mechanism to explain lower concentrations of atmospheric carbon dioxide during ice ages; however, unequivocal signatures of this storage have not been found. In seawater, the dissolved gases oxygen and carbon dioxide are linked via the production and decay of organic material, with reconstructions of low oxygen concentrations in the past indicating an increase in biologically mediated carbon storage. [...]"

Source: Nature
Authors: Babette A. A. Hoogakker et al.
DOI: 10.1038/s41586-018-0589-x

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Abstract.

"Photic zone euxinia (PZE) is a condition where anoxic, H₂S-rich waters occur in the photic zone (PZ). PZE has been invoked as an impediment to the evolution of complex life on early Earth and as a kill mechanism for Phanerozoic mass extinctions. Here, we investigate the potential application of mercury (Hg) stable isotopes in marine sedimentary rocks as a proxy for PZE by measuring Hg isotope compositions in late Mesoproterozoic (∼1.1 Ga) shales that have independent evidence of PZE during discrete intervals. [...]"

Source: PNAS
Authors: Wang Zheng et al.
DOI: 10.1073/pnas.1721733115

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Abstract.

"Climate change, rising atmospheric carbon dioxide, excess nutrient inputs, and pollution in its many forms are fundamentally altering the chemistry of the ocean, often on a global scale and, in some cases, at rates greatly exceeding those in the historical and recent geological record. Major observed trends include a shift in the acid-base chemistry of seawater, reduced subsurface oxygen both in near-shore coastal water and in the open ocean, rising coastal nitrogen levels, and widespread increase in mercury and persistent organic pollutants. [...]"

Source: Science
Author: Scott C. Doney
DOI: 10.1126/science.1185198

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Abstract.

"A productive biosphere and oxygenated atmosphere are defining features of Earth and are fundamentally linked. Here I argue that cellular metabolism imposes central constraints on the historical trajectories of biopsheric productivity and atmospheric oxygenation. Photosynthesis depends on iron, but iron is highly insoluble under the aerobic conditions produced by oxygenic photosynthesis. [...]"

Source: PeerJ Preprints
Author: Rogier Braakman
DOI: 10.7287/peerj.preprints.27269v1

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Abstract.

"During Earth’s history, precipitation of calcium carbonate by heterotrophic microbes has substantially contributed to the genesis of copious amounts of carbonate sediment and its subsequent lithification. Previous work identified the microbial sulfur and nitrogen cycle as principal pathways involved in the formation of marine calcium carbonate deposits. While substantial knowledge exists for the importance of the sulfur cycle, specifically sulfate reduction, with regard to carbonate formation, information about carbonate genesis connected to the microbial nitrogen cycle is dissatisfactory. [...]"

Source: Geochimica et Cosmochimica Acta
Authors: S. Krause et al
DOI: 10.1016/j.gca.2018.09.018

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Abstract.

"Climate impacts on marine ecosystems may be exacerbated by other, more local stressors interacting synergistically, such as pollution and overexploitation of marine resources. The reduction of these human stressors has been proposed as an achievable way of retaining ecosystems within a “safe operating space” (SOS), where they remain resilient to ongoing climate change. However, the operability of an SOS requires a thorough understanding of the spatial distribution of these climate and human impacts. [...]"

Source: Scientific Reports
Authors: Francisco Ramírez et al.
DOI: 10.1038/s41598-018-33237-w

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Abstract.

"In the subpolar North Atlantic, four sediment cores were taken. All of them were suitable for reconstructing the dynamics of the meridional overturning circulation in the late Quaternary. Stratigraphy of the cores was performed by carbonate analyses, study of planktonic foraminifera, and oxygen isotopic composition in Neogloboquadrina pachyderma sin. Study of benthonic foraminifera assemblages has shown significant differences in the deep-water dynamics in the late Quaternary related to water exchange between the North Atlantic and Arctic seas. [...]"

Source: Oceanology
Authors: N.P. Lukashina
DOI: 10.1134/S0001

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Abstract.

"We have observed that marine macroalgae produce sound during photosynthesis. The resultant soundscapes correlate with benthic macroalgal cover across shallow Hawaiian coral reefs during the day, despite the presence of other biological noise. Likely ubiquitous but previously overlooked, this source of ambient biological noise in the coastal ocean is driven by local supersaturation of oxygen near the surface of macroalgal filaments, and the resultant formation and release of oxygen-containing bubbles into the water column. During release, relaxation of the bubble to a spherical shape creates a monopole sound source that ‘rings’ at the Minnaert frequency. [...]"

Source: PLOS ONE
Authors: Simon E. Freeman et al.
DOI: 10.1371/journal.pone.0201766

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Abstract.

"Paleorecords and modeling studies suggest that instabilities in the Atlantic Meridional Overturning Circulation (AMOC) strongly affect the low-latitude climate, namely via feedbacks on the Atlantic Intertropical Convergence Zone (ITCZ). Despite the pronounced millennial-scale overturning and climatic variability documented in the subpolar North Atlantic during the last interglacial period (MIS 5e), studies on cross-latitudinal teleconnections remain very limited. This precludes a full understanding of the mechanisms controlling subtropical climate evolution across the last warm cycle. [...]"

Source: Climate of the Past
Authors: Anastasia Zhuravleva and Henning A. Bauch
DOI: 10.5194/cp-14-1361-2018

Read the full article here.