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Processes and patterns of oceanic nutrient limitation
Microbial activity is a fundamental component of oceanic nutrient cycles. Photosynthetic microbes, collectively termed phytoplankton, are responsible for the vast majority of primary production in
Enhanced biological carbon consumption in a high CO2 ocean
It is shown that dissolved inorganic carbon consumption of a natural plankton community maintained in mesocosm enclosures at initial CO2 partial pressures increases with rising CO2, and the observed responses have implications for a variety of marine biological and biogeochemical processes, and underscore the importance of biologically driven feedbacks in the ocean to global change.
Declining oxygen in the global ocean and coastal waters
Improved numerical models of oceanographic processes that control oxygen depletion and the large-scale influence of altered biogeochemical cycles are needed to better predict the magnitude and spatial patterns of deoxygenation in the open ocean, as well as feedbacks to climate.
Impacts of Atmospheric Anthropogenic Nitrogen on the Open Ocean
Although ∼10% of the ocean's drawdown of atmospheric anthropogenic carbon dioxide may result from this atmospheric nitrogen fertilization, leading to a decrease in radiative forcing, up to about two-thirds of this amount may be offset by the increase in N2O emissions.
Future ocean acidification will be amplified by hypoxia in coastal habitats
Coastal ocean acidification experimental designs need to be closely adjusted to carbonate system variability within the specific habitat, as the magnitude of expected changes in pCO2 in these regions indicates that coastal systems may be more endangered by future global climate change than previously thought.
Eddy-induced enhancement of primary production in a model of the North Atlantic Ocean
In steady state, the export of photosynthetically fixed organic matter to the deep ocean has to be balanced by an upward flux of nutrients into the euphotic zone. Indirect geochemical estimates of
Future changes in climate, ocean circulation, ecosystems, and biogeochemical cycling simulated for a business‐as‐usual CO2 emission scenario until year 4000 AD
A new model of global climate, ocean circulation, ecosystems, and biogeochemical cycling, including a fully coupled carbon cycle, is presented and evaluated. The model is consistent with multiple
Sensitivities of marine carbon fluxes to ocean change
This analysis underscores that many of the responses of the seawater carbonate system and of the ocean's physical and biological carbon pumps to (i) ocean warming and the associated changes in vertical mixing and overturning circulation, and (ii) ocean acidification and carbonation have the potential for significant feedback to the climate system.
Simultaneous data-based optimization of a 1D-ecosystem model at three locations in the North Atlantic: Part I— Method and parameter estimates
An optimization experiment is performed with a vertically resolved, nitrogen-based ecosystem model, composed of four state variables (NPZD-model): dissolved inorganic nitrogen (N), phytoplankton (P),
Nitrogen cycling driven by organic matter export in the South Pacific oxygen minimum zone
Oxygen minimum zones are expanding globally, and at present account for around 20–40% of oceanic nitrogen loss. Heterotrophic denitrification and anammox—anaerobic ammonium oxidation with nitrite—are