Publications associées à Ocean deoxygenation

X-ray chemical imaging for assessing redox microsites within soils and sediments

Redox reactions underlie several biogeochemical processes and are typically spatiotemporally heterogeneous in soils and sediments. However, redox heterogeneity has yet to be incorporated into mainstream conceptualizations and modeling of soil biogeochemist ...

Frontiers Media Sa2024

Characteristics and sources of fluorescent aerosols in the central Arctic Ocean

Julia Schmale, Benjamin Jérémy Laurent Heutte, Jakob Boyd Pernov, Nora Bergner, Ivo Fabio Beck, Oliver Müller, Hélène Paule Angot, Alireza Moallemi, Margarida Teles Nogueira Rolo, Markus Frey

The Arctic is sensitive to cloud radiative forcing. Due to the limited number of aerosols present throughout much of the year, cloud formation is susceptible to the presence of cloud condensation nuclei and ice nucleating particles (INPs). Primary biologic ...

2024

Near-bed stratification controls bottom hypoxia in ice-covered alpine lakes

Damien Bouffard, Camille Roland Marie Minaudo, Tomy Doda, Hugo Nicolás Ulloa Sánchez, Hannah Elisa Chmiel, Janine Rüegg, Nicolas Thomas Georges Escoffier, Pascal Perolo

In ice-covered lakes, near-bottom oxygen concentration decreases for most of the wintertime, sometimes down to the point that bottom waters become hypoxic. Studies insofar have reached divergent conclusions on whether climate change limits or reinforces th ...

American Society of Limnology and Oceanography2023

Polar oceans and sea ice in a changing climate

Julia Schmale, Hélène Paule Angot, Jenny Thomas

Polar oceans and sea ice cover 15% of the Earth’s ocean surface, and the environment is changing rapidly at both poles. Improving knowledge on the interactions between the atmospheric and oceanic realms in the polar regions, a Surface Ocean–Lower Atmospher ...

2023

Highly Active Ice‐Nucleating Particles at the Summer North Pole

Julia Schmale

The amount of ice versus supercooled water in clouds is important for their radiative properties and role in climate feedbacks. Hence, knowledge of the concentration of ice-nucleating particles (INPs) is needed. Generally, the concentrations of INPs are fo ...

2022

Evidence that Pacific tuna mercury levels are driven by marine methylmercury production and anthropogenic inputs

Hélène Paule Angot

Pacific Ocean tuna is among the most-consumed seafood products but contains relatively high levels of the neurotoxin methylmercury. Limited observations suggest tuna mercury levels vary in space and time, yet the drivers are not well understood. Here, we m ...

National Academy of Sciences2022

Arctic atmospheric mercury: Sources and changes

Hélène Paule Angot

Global anthropogenic and legacy mercury (Hg) emissions are the main sources of Arctic Hg contamination, primarily transported there via the atmosphere. This review summarizes the state of knowledge of the global anthropogenic sources of Hg emissions, and e ...

2022

Sources, Occurrence and Characteristics of Fluorescent Biological Aerosol Particles Measured over the Pristine Southern Ocean

Julia Schmale, Andrea Baccarini, Robin Lewis Modini, Sebastian Johannes Heinz-Josef Landwehr, Alireza Moallemi

In this study we investigate the occurrence of primary biological aerosol particles (PBAP) over all sectors of the Southern Ocean (SO) based on a 90-day dataset collected during the Antarctic Circumnavigation Expedition (ACE) in austral summer 2016-2017. S ...

2021

Bias-Adaptable CO2-to-CO Conversion via Tuning the Binding of Competing Intermediates

Yelin Hu, Jun Li, Shilong Wang, Han Zhang, An Zhang

CO2 electroreduction powered by renewable electricity represents a promising method to enclose anthropogenic carbon cycle. Current catalysts display high selectivity toward the desired product only over a narrow potential window due primarily to unoptimize ...

AMER CHEMICAL SOC2021

Integrating environmental variability to broaden the research on coral responses to future ocean conditions

Cristina Martin Olmos, Nils Rädecker

Our understanding of the response of reef-building corals to changes in their physical environment is largely based on laboratory experiments, analysis of long-term field data, and model projections. Experimental data provide unique insights into how organ ...

2021

Microbes support enhanced nitrogen requirements of coral holobionts in a high CO 2 environment

Nils Rädecker, Gabriela Hannah Holligan Perna

Ocean acidification is posing a threat to calcifying organisms due to the increased energy requirements of calcification under high CO2 conditions. The ability of scleractinian corals to cope with future ocean conditions will thus depend on their ability t ...

2021

Flow and epiphyte growth effects on the thermal, optical and chemical microenvironment in the leaf phyllosphere of seagrass (Zostera marina)

Anna Depetris, Michael Kühl

Intensified coastal eutrophication can result in an overgrowth of seagrass leaves by epiphytes, which is a major threat to seagrass habitats worldwide, but little is known about how epiphytic biofilms affect the seagrass phyllosphere. The physico-chemical ...

ROYAL SOC2020

Science, Diplomacy, and the Red Sea's Unique Coral Reef: It's Time for Action

Anders Meibom, Maoz Fine

Rapid ocean warming due to climate change poses a serious risk to the survival of coral reefs. It is estimated that 70-90 percent of all reefs will be severely degraded by mid-century even if the 1.5 degrees C goal of the Paris Climate Agreement is achieve ...

FRONTIERS MEDIA SA2020

Enhanced trace element mobilization by Earth's ice sheets

Tyler Joe Kohler

Trace elements sustain biological productivity, yet the significance of trace element mobilization and export in subglacial runoff from ice sheets is poorly constrained at present. Here, we present size-fractionated (0.02, 0.22, and 0.45 mu m) concentratio ...

National Academy of Sciences2020

As release under the microbial sulfate reduction during redox oscillations in the upper Mekong delta aquifers, Vietnam: A mechanistic study

Rizlan Bernier-Latmani, Manon Frutschi, Laurent Louis José Charlet

The impact of seasonal fluctuations linked to monsoon and irrigation generates redox oscillations in the subsurface, influencing the release of arsenic (As) in aquifers. Here, the biogeochemical control on As mobility was investigated in batch experiments ...

2019

Life-history trade-offs and limitations associated with phenotypic adaptation under future ocean warming and elevated salinity

Emma Mary Gibbin, Félix Christen

Little is known about the life-history trade-offs and limitations, and the physiological mechanisms that are associated with phenotypic adaptation to future ocean conditions. To address this knowledge gap, we investigated the within-and trans-generation li ...

ROYAL SOC2019

Allometric Scaling of physiologically-relevant organoids

Andrea Rinaldo

The functional and structural resemblance of organoids to mammalian organs suggests that they might follow the same allometric scaling rules. However, despite their remarkable likeness to downscaled organs, non-luminal organoids are often reported to posse ...

Nature Research2019

Pyrogenic iron: The missing link to high iron solubility in aerosols

Athanasios Nenes, Yan Feng

Atmospheric deposition is a source of potentially bioavailable iron (Fe) and thus can partially control biological productivity in large parts of the ocean. However, the explanation of observed high aerosol Fe solubility compared to that in soil particles ...

2019

Relationships between key functional traits of the waterlily Nuphar lutea and wetland nutrient content

Charles Pierre Roger Henriot

Little attention has been paid to how aquatic habitat characteristics affect the traits of plant species. Nuphar lutea (L.) Sm. is a keystone species distributed across temperate regions of Europe, northwest Africa and western Asia. Its apparently low phen ...

2019

Scaling oxygen microprofiles at the sediment interface of deep stratified waters

Alfred Johny Wüest, Damien Bouffard, Robert Vincent Schwefel, Miki Hondzo

Dissolved oxygen microprofiles at the sediment-water interface of Lake Geneva were measured concurrently with velocities 0.25 to 2m above the sediment. The measurements and scaling analyses indicate dissolved oxygen fluctuations and turbulent fluxes in exc ...

American Geophysical Union2017