Diel and tidal pCO2 × O2 fluctuations provide physiological refuge to early life stages of a coastal forage fish
"Coastal ecosystems experience substantial natural fluctuations in pCO2 and dissolved oxygen (DO) conditions on diel, tidal, seasonal and interannual timescales. Rising carbon dioxide emissions and anthropogenic nutrient input are expected to increase these pCO2 and DO cycles in severity and duration of acidification and hypoxia. [...]"
Source: Scientific Reports
Authors: Emma L. Cross et al.
Large projected decline in dissolved oxygen in a eutrophic estuary due to climate change
"Climate change is known to cause deoxygenation in the open ocean, but its effects on eutrophic and seasonally hypoxic estuaries and coastal oceans are less clear. Using Chesapeake Bay as a study site, we conducted climate downscaling projections for dissolved oxygen and found that the hypoxic and anoxic volumes would increase by 10‐30% between the late 20th and mid‐21st century. [...]"
Source: JGR Oceans
Authors: Wenfei Ni et al.
Spatiotemporal changes of ocean carbon species in the western North Pacific using parameterization technique
"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.
Climatic, physical, and biogeochemical changes drive rapid oxygen loss and recovery in a marine ecosystem
"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.
Wind-driven stratification patterns and dissolved oxygen depletion in the area off the Changjiang (Yangtze) Estuary
"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. [...]"
Authors: Taavi Liblik et al.
Seasonal variability of the southern tip of the Oxygen Minimum Zone in the eastern South Pacific (30°‐38°S): A modeling study
"We investigate the seasonal variability of the southern tip (30°–38°S) of the eastern South Pacific oxygen minimum zone (OMZ) based on a high horizontal resolution (1/12°) regional coupled physical‐biogeochemical model simulation. The simulation is validated by available in situ observations and the OMZ seasonal variability is documented. The model OMZ, bounded by the contour of 45 μM, occupies a large volume (4.5x104 km3) during the beginning of austral winter and a minimum (3.5x104 km3) at the end of spring, just 1 and 2 months after the southward transport of the Peru‐Chile Undercurrent (PCUC) is maximum and minimum, respectively. [...]"
Source: JGR Oceans
Authors: Matias Pizarro‐Koch et al.
A New Characterization of the Upper Waters of the central Gulf of México based on Water Mass Hydrographic and Biogeochemical Characteristics
" In the Gulf of Mexico (GoM) at least three near-surface water masses are affected by mesoscale processes that modulate the biogeochemical cycles. Prior studies have presented different classifications of water masses where the greater emphasis was on deep waters and not on the surface waters (σθ < 26 kg m−3), as in this work. Here presents a new classification of water masses in the GoM, based on thermohaline properties and dissolved oxygen (DO) concentration using data from a total of five summer and winter cruises carried out primarily in the central GoM. [...]"
Authors: Gabriela Yareli Cervantes-Diaz et al.
Effects of upwelling duration and phytoplankton growth regime on dissolved oxygen levels in an idealized Iberian Peninsula upwelling system
"We apply a coupled modelling system composed of a state-of-the-art hydrodynamical model and a low complexity biogeochemical model to an idealized Iberian Peninsula upwelling system to identify the main drivers of dissolved oxygen variability and to study its response to changes in the duration of the upwelling season and in phytoplankton growth regime. [...]"
Source: Nonlinear Processes in Geophysics (preprint)
Authors: João H. Bettencourt et al.
Ferry in Alaska monitors ocean acidification
"The last two years MV Columbia records the ocean’s vitals every three minutes, along a 1,600-kilometer route through the Inside Passage. This includes the coastal region from Puget Sound to the Alaska Panhandle. The ship measures the sea's temperature, salinity, dissolved oxygen content, and carbon dioxide concentration, aiming to monitor ocean acidification. [...]"
Climate change could shrink oyster habitat in California
"Ocean acidification is bad news for shellfish, as it makes it harder for them to form their calcium-based shells. But climate change could also have multiple other impacts that make California bays less hospitable to shelled organisms like oysters, which are a key part of the food web.
Changes to water temperature and chemistry resulting from human-caused climate change could shrink the prime habitat and farming locations for oysters in California bays, according to a new study from the University of California, Davis. [...]"
Source: Science Daily