Ocean acidification reduces growth and grazing impact of Antarctic heterotrophic nanoflagellates
"High-latitude oceans have been identified as particularly vulnerable to ocean acidification if anthropogenic CO2 emissions continue. Marine microbes are an essential part of the marine food web and are a critical link in biogeochemical processes in the ocean, such as the cycling of nutrients and carbon. Despite this, the response of Antarctic marine microbial communities to ocean acidification is poorly understood. We investigated the effect of increasing fCO2 on the growth of heterotrophic nanoflagellates (HNFs), nano- and picophytoplankton, and prokaryotes (heterotrophic Bacteria and Archaea) in a natural coastal Antarctic marine microbial community from Prydz Bay, East Antarctica.[...]"
Authors: Stacy Deppeler et.al
Monitoring ocean biogeochemistry with autonomous platforms
"Human activities have altered the state of the ocean, leading to warming, acidification and deoxygenation. These changes impact ocean biogeochemistry and influence ecosystem functions and ocean health. The long-term global effects of these changes are difficult to predict using current satellite sensing and traditional in situ observation techniques. [...]"
Source: Nature Reviews Earth & Environment
Authors: Fei Chai et al.
Emergent constraint on Arctic Ocean acidification in the twenty-first century
"The ongoing uptake of anthropogenic carbon by the ocean leads to ocean acidification, a process that results in a reduction in pH and in the saturation state of biogenic calcium carbonate minerals aragonite (Ωarag) and calcite (Ωcalc). Because of its naturally low Ωarag and Ωcalc (refs.), the Arctic Ocean is considered the region most susceptible to future acidification and associated ecosystem impacts. [...]"
Authors: Jens Terhaar et al.
Twenty-first century ocean warming, acidification, deoxygenation, and upper-ocean nutrient and primary production decline from CMIP6 model projections
"Anthropogenic climate change is projected to lead to ocean warming, acidification, deoxygenation, reductions in near-surface nutrients, and changes to primary production, all of which are expected to affect marine ecosystems. Here we assess projections of these drivers of environmental change over the twenty-first century from Earth system models (ESMs) participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6) that were forced under the CMIP6 Shared Socioeconomic Pathways (SSPs). [...]"
Authors: Lester Kwiatkowski et al.
Additive impacts of deoxygenation and acidification threaten marine biota
"Deoxygenation in coastal and open‐ocean ecosystems rarely exists in isolation but occurs concomitantly with acidification. Here, we first combine meta‐data of experimental assessments from across the globe to investigate the potential interactive impacts of deoxygenation and acidification on a broad range of marine taxa. [...]"
Source: Global Change Biology
Authors: Alexandra Steckbauer et al.
Ocean acidification interacts with variable light to decrease growth but increase particulate organic nitrogen production in a diatom
"Phytoplankton in the upper oceans are exposed to changing light levels due to mixing, diurnal solar cycles and weather conditions. Consequently, effects of ocean acidification are superimposed upon responses to variable light levels. We therefore grew a model diatom Thalassiosira pseudonana under either constant or variable light but at the same daily photon dose, with current low (400 μatm, LC) and future high CO2 (1000 μatm, HC) treatments. [...]"
Source: Marine Environmental Research
Authors: Wei Li et al.
Short-term effects of hypoxia are more important than effects of ocean acidification on grazing interactions with juvenile giant kelp
"Species interactions are crucial for the persistence of ecosystems. Within vegetated habitats, early life stages of plants and algae must survive factors such as grazing to recover from disturbances. However, grazing impacts on early stages, especially under the context of a rapidly changing climate, are largely unknown. [...]"
Source: Scientific Reports
Authors: Crystal A. Ng & Fiorenza Micheli
No “Ocean Super-Year” without Marine Regions
"This new decade starts at a critical moment for the future of the Ocean. There is strong agreement among experts that decisions taken in the next ten years will be critical for the future of the Ocean. The current ecological crisis demands a radical shift in the way we treat the marine environment, its precious wildlife, and its invaluable natural resources. We are witnessing continued loss of biodiversity, overfishing, habitat destruction, pollution, and many other serious impacts from human activities – all compounded by climate change, Ocean deoxygenation and acidification. [...]"
Source: International Institute for Sustainable Development
Upwelling Bays: How Coastal Upwelling Controls Circulation, Habitat, and Productivity in Bays
"Bays in coastal upwelling regions are physically driven and biochemically fueled by their interaction with open coastal waters. Wind-driven flow over the shelf imposes a circulation in the bay, which is also influenced by local wind stress and thermal bay–ocean density differences. Three types of bays are recognized based on the degree of exposure to coastal currents and winds (wide-open bays, square bays, and elongated bays), and the characteristic circulation and stratification patterns of each type are described. Retention of upwelled waters in bays allows for dense phytoplankton blooms that support productive bay ecosystems. [...]"
Source: Annual Review of Marine Science
Authors: John L. Largier
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.