News

Spatiotemporal changes of ocean carbon species in the western North Pacific using parameterization technique

Abstract.

"We constructed parameterizations for the estimation of dissolved inorganic carbon (DIC) and pH in the western North Pacific, including Japanese coastal regions. Parameterizations, determined as a function of potential temperature (θ) and dissolved oxygen (DO), provided strong correlations with direct measurements for DIC [the coefficient of determination (R2) = 0.99; the root mean square error (RMSE) = 8.49 µmol kg−1] and pH (R2 = 0.98, RMSE = 0.030). [...]"

Source: Journal of Oceanography
Authors: Yutaka W. Watanabe et al.
DOI: 10.1007/s10872-019-00532-7

Read the full article here.

 


Response of N2O production rate to ocean acidification in the western North Pacific

Abstract.

"Ocean acidification, induced by the increase in anthropogenic CO2 emissions, has a profound impact on marine organisms and biogeochemical processes1. The response of marine microbial activities to ocean acidification might play a crucial role in the future evolution of air–sea fluxes of biogenic gases such as nitrous oxide (N2O), a strong GHG and the dominant stratospheric ozone-depleting substance2. Here, we examine the response of N2O production from nitrification to acidification in a series of incubation experiments conducted in subtropical and subarctic western North Pacific. [...]"

Source: Nature Climate Change
Authors: Florian Breider et al.
DOI: 10.1038/s41558-019-0605-7

Read the full article here.


Meeting climate targets by direct CO2 injections: what price would the ocean have to pay?

Abstract.

"We investigate the climate mitigation potential and collateral effects of direct injections of captured CO2 into the deep ocean as a possible means to close the gap between an intermediate CO2 emissions scenario and a specific temperature target, such as the 1.5 C target aimed for by the Paris Agreement. For that purpose, a suite of approaches for controlling the amount of direct CO2 injections at 3000 m water depth are implemented in an Earth system model of intermediate complexity. [...]"

Source: Earth System Dynamics
Authors: Fabian Reith et al.
DOI: 10.5194/esd-10-711-2019

Read the full article here.


Controls on redox-sensitive trace metals in the Mauritanian oxygen minimum zone

Abstract.

"The availability of the micronutrient iron (Fe) in surface waters determines primary production, N2 fixation, and microbial community structure in large parts of the world's ocean, and thus it plays an important role in ocean carbon and nitrogen cycles. Eastern boundary upwelling systems and the connected oxygen minimum zones (OMZs) are typically associated with elevated concentrations of redox-sensitive trace metals (e.g., Fe, manganese (Mn), and cobalt (Co)), with shelf sediments typically forming a key source. [...]"

Source: Biogeosciences
Authors: Insa Rapp et al.
DOI: 10.5194/bg-16-4157-2019

Read the full article here.


Climatic, physical, and biogeochemical changes drive rapid oxygen loss and recovery in a marine ecosystem

Abstract.

"Dissolved oxygen (DO) concentrations shape the biogeochemistry and ecological structure of aquatic ecosystems; as a result, understanding how and why DO varies in space and time is of fundamental importance. Using high-resolution, in situ DO time-series collected over the course of a year in a novel marine ecosystem (Jellyfish Lake, Palau), we show that DO declined throughout the marine lake and subsequently recovered in the upper water column. [...]"

Source: Scientific Reports
Authors: Jesse Wilson et al.
DOI: 10.1038/s41598-019-52430-z

Read the full article here.


The Development and Validation of a Profiling Glider Deep ISFET-Based pH Sensor for High Resolution Observations of Coastal and Ocean Acidification

Abstract.

"Coastal and ocean acidification can alter ocean biogeochemistry, with ecological consequences that may result in economic and cultural losses. Yet few time series and high resolution spatial and temporal measurements exist to track the existence and movement of water low in pH and/or carbonate saturation. Past acidification monitoring efforts have either low spatial resolution (mooring) or high cost and low temporal and spatial resolution (research cruises). [...]"

Source: Frontiers in Marine Science
Authors: Grace K. Saba et al.
DOI: 10.3389/fmars.2019.00664

Read the full article here.

 


Decadal acidification in Atlantic and Mediterranean water masses exchanging at the Strait of Gibraltar

Abstract.

"Seawater pH is undergoing a decreasing trend due to the absorption of atmospheric CO2, a phenomenon known as ocean acidification (OA). Biogeochemical processes occurring naturally in the ocean also change pH and hence, for an accurate assessment of OA, the contribution of the natural component to the total pH variation must be quantified. [...]"

Source: Scientific Reports
Authors: Susana Flecha et al.
DOI: 10.1038/s41598-019-52084-x

Read the full article here.


Perspectives on in situ Sensors for Ocean Acidification Research

Abstract.

"As ocean acidification (OA) sensor technology develops and improves, in situ deployment of such sensors is becoming more widespread. However, the scientific value of these data depends on the development and application of best practices for calibration, validation, and quality assurance as well as on further development and optimization of the measurement technologies themselves. Here, we summarize the results of a 2-day workshop on OA sensor best practices held in February 2018, in Victoria, British Columbia, Canada, drawing on the collective experience and perspectives of the participants. [...]"

Source: Frontiers in Marine Science
Authors: Akash R. Sastri et al.
DOI: 10.3389/fmars.2019.00653

Read the full article here.


Wind-driven stratification patterns and dissolved oxygen depletion in the area off the Changjiang (Yangtze) Estuary

Abstract.

"The area off the Changjiang Estuary is under strong impact of fresh water and anthropogenic nutrient load from the Changjiang River. The seasonal hypoxia in the area has variable location and range, but the decadal trend reveals expansion and intensification of the dissolved oxygen (DO) depletion. [...]"

Source: Biogeosciences
Authors: Taavi Liblik et al.
DOI: 10.5194/bg-2019-421

Read the full article here.