Thermodynamics of the Pelagic Ecosystem: Elementary Closure Conditions for Biological Production in the Open Ocean

1984 ◽  
pp. 49-84 ◽  
Author(s):  
Trevor Platt ◽  
Marlon Lewis ◽  
Richard Geider
Keyword(s):  
Open Ocean ◽  
Pelagic Ecosystem ◽  
Biological Production ◽  
Closure Conditions ◽  
Elementary Closure

scholarly journals Air-sea CO<sub>2</sub> fluxes and the controls on ocean surface <i>p</i>CO<sub>2</sub> seasonal variability in the coastal and open-ocean southwestern Atlantic Ocean: a modeling study

2015 ◽  
Vol 12 (19) ◽  
pp. 5793-5809 ◽  
Author(s):  
R. Arruda ◽  
P. H. R. Calil ◽  
A. A. Bianchi ◽  
S. C. Doney ◽  
N. Gruber ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Seasonal Variability ◽  
Dissolved Inorganic Carbon ◽  
Open Ocean ◽  
Atmospheric Co2 ◽  
Biogeochemical Model ◽  
Southwestern Atlantic ◽  
Biological Production ◽  
The North ◽  
Southwestern Atlantic Ocean

Abstract. We use an eddy-resolving, regional ocean biogeochemical model to investigate the main variables and processes responsible for the climatological spatio-temporal variability of pCO2 and the air-sea CO2 fluxes in the southwestern Atlantic Ocean. Overall, the region acts as a sink of atmospheric CO2 south of 30° S, and is close to equilibrium with the atmospheric CO2 to the north. On the shelves, the ocean acts as a weak source of CO2, except for the mid/outer shelves of Patagonia, which act as sinks. In contrast, the inner shelves and the low latitude open ocean of the southwestern Atlantic represent source regions. Observed nearshore-to-offshore and meridional pCO2 gradients are well represented by our simulation. A sensitivity analysis shows the importance of the counteracting effects of temperature and dissolved inorganic carbon (DIC) in controlling the seasonal variability of pCO2. Biological production and solubility are the main processes regulating pCO2, with biological production being particularly important on the shelves. The role of mixing/stratification in modulating DIC, and therefore surface pCO2, is shown in a vertical profile at the location of the Ocean Observatories Initiative (OOI) site in the Argentine Basin (42° S, 42° W).

AN EXTINCTION OF OPEN-OCEAN SHARKS 19 MA AND ITS IMPACT ON MODERN PELAGIC ECOSYSTEM STRUCTURE

2019 ◽  
Author(s):  
Elizabeth C. Sibert ◽  
◽  
Leah Rubin ◽  
Leah Rubin ◽  
Leah Rubin
Keyword(s):  
Open Ocean ◽  
Ecosystem Structure ◽  
Pelagic Ecosystem

Biological production of methyl bromide in the coastal waters of the North Sea and open ocean of the northeast Atlantic

1999 ◽  
Vol 64 (4) ◽  
pp. 267-285 ◽  
Author(s):  
J.M Baker ◽  
C.E Reeves ◽  
P.D Nightingale ◽  
S.A Penkett ◽  
S.W Gibb ◽  
...  
Keyword(s):  
North Sea ◽  
Methyl Bromide ◽  
Coastal Waters ◽  
Open Ocean ◽  
Biological Production ◽  
Northeast Atlantic ◽  
The North ◽  
The North Sea

scholarly journals NW European shelf under climate warming: implications for open ocean – shelf exchange, primary production, and carbon absorption

2013 ◽  
Vol 10 (6) ◽  
pp. 3767-3792 ◽  
Author(s):  
M. Gröger ◽  
E. Maier-Reimer ◽  
U. Mikolajewicz ◽  
A. Moll ◽  
D. Sein
Keyword(s):  
Primary Production ◽  
North Sea ◽  
Open Ocean ◽  
Global Ocean ◽  
Fish Stock ◽  
Co2 Absorption ◽  
Biological Production ◽  
The North ◽  
European Shelf ◽  
The North Sea

Abstract. Shelves have been estimated to account for more than one-fifth of the global marine primary production. It has been also conjectured that shelves strongly influence the oceanic absorption of anthropogenic CO2 (carbon shelf pump). Owing to their coarse resolution, currently applied global climate models are inappropriate to investigate the impact of climate change on shelves and regional models do not account for the complex interaction with the adjacent open ocean. In this study, a global ocean general circulation model and biogeochemistry model were set up with a distorted grid providing a maximal resolution for the NW European shelf and the adjacent northeast Atlantic. Using model climate projections we found that already a~moderate warming of about 2.0 K of the sea surface is linked with a reduction by ~ 30% of the biological production on the NW European shelf. If we consider the decline of anthropogenic riverine eutrophication since the 1990s, the reduction of biological production amounts is even larger. The relative decline of NW European shelf productivity is twice as strong as the decline in the open ocean (~ 15%). The underlying mechanism is a spatially well confined stratification feedback along the continental shelf break. This feedback reduces the nutrient supply from the deep Atlantic to about 50%. In turn, the reduced productivity draws down CO2 absorption in the North Sea by ~ 34% at the end of the 21st century compared to the end of the 20th century implying a strong weakening of shelf carbon pumping. Sensitivity experiments with diagnostic tracers indicate that not more than 20% of the carbon absorbed in the North Sea contributes to the long-term carbon uptake of the world ocean. The rest remains within the ocean's mixed layer where it is exposed to the atmosphere. The predicted decline in biological productivity, and decrease of phytoplankton concentration (in the North Sea by averaged 25%) due to reduced nutrient imports from the deeper Atlantic will probably affect the local fish stock negatively and therefore fisheries in the North Sea.

scholarly journals NW European shelf under climate warming: implications for open ocean – shelf exchange, primary production, and carbon absorption

2012 ◽  
Vol 9 (11) ◽  
pp. 16625-16662 ◽  
Author(s):  
M. Gröger ◽  
E. Maier-Reimer ◽  
U. Mikolajewicz ◽  
A. Moll ◽  
D. Sein
Keyword(s):  
Primary Production ◽  
North Sea ◽  
Open Ocean ◽  
Global Ocean ◽  
Fish Stock ◽  
Co2 Absorption ◽  
Biological Production ◽  
The North ◽  
European Shelf ◽  
The North Sea

Abstract. Shelves have been estimated to account for more than one fifth of the global marine primary production. It has been also conjectured that shelves strongly influence the oceanic absorption of atmospheric CO2 (carbon shelf pump). Owing to their coarse resolution, currently applied global climate models are inappropriate to investigate the impact of climate change on shelfs and regional models do not account for the complex interaction with the adjacent open ocean. In this study, a global ocean general circulation model and biogeochemistry model were set up with a distorted grid providing a maximal resolution for the NW European shelf and the adjacent North Atlantic. Using model climate projections we found that already a moderate warming of about 2.0 K of the sea surface is linked with a reduction by ~ 30% of biological production on the NW European shelf. If we consider the decline of anthropogenic riverine eutrophication since the 90's the reduction of biological production amounts to 39%. The decline of NW European shelf productivity is twice as strong as the decline in the open ocean (~ 15%). The underlying mechanism is a spatially well confined stratification feedback along the continental shelf break. This feedback reduces the nutrient supply from the deep Atlantic to about 50%. In turn, the reduced productivity draws down CO2 absorption on the NW European shelf by ~ 34% at the end of the 21st century compared to the end of the 20th century implying a strong weakening of shelf carbon pumping. Sensitivity experiments with diagnostic tracers indicate that not more than 20% of the carbon absorbed in the North Sea contributes to the long term carbon uptake of the world ocean. The rest remains within the ocean mixed layer where it is exposed to the atmosphere. The predicted decline in biological productivity and decrease of phytoplankton concentration (by averaged 25%) due to reduced nutrient imports from the deeper Atlantic will probably negatively affect the local fish stock and therefore fisheries in the North Sea.

scholarly journals Air–sea CO<sub>2</sub> fluxes and the controls on ocean surface <i>p</i>CO<sub>2</sub> variability in coastal and open-ocean southwestern Atlantic Ocean: a modeling study

2015 ◽  
Vol 12 (10) ◽  
pp. 7369-7409 ◽  
Author(s):  
R. Arruda ◽  
P. H. R. Calil ◽  
A. A. Bianchi ◽  
S. C. Doney ◽  
N. Gruber ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Dissolved Inorganic Carbon ◽  
Open Ocean ◽  
Atmospheric Co2 ◽  
Biogeochemical Model ◽  
Southwestern Atlantic ◽  
Biological Production ◽  
The North ◽  
Southwestern Atlantic Ocean ◽  
Spatio Temporal

Abstract. We use an eddy-resolving, regional ocean biogeochemical model to investigate the main variables and processes responsible for the climatological spatio-temporal variability of pCO2 and the air–sea CO2 fluxes in the southwestern Atlantic Ocean. Overall, the region acts as sink of atmospheric CO2 south of 30° S, and is close to equilibrium with the atmospheric CO2 to the north. On the shelves, the ocean acts as a weak source of CO2, except for the mid/outer shelves of Patagonia, which act as sinks. In contrast, the inner shelves and the low latitude open ocean of the southwestern Atlantic represent source regions. Observed nearshore-to-offshore and meridional pCO2 gradients are well represented by our simulation. A sensitivity analysis shows the importance of the counteracting effects of temperature and dissolved inorganic carbon (DIC) in controlling the seasonal variability of pCO2. Biological production and solubility are the main processes regulating pCO2, with biological production being particularly important on the shelf regions. The role of mixing/stratification in modulating DIC, and therefore surface pCO2 is shown in a vertical profile at the location of the Ocean Observatories Initiative (OOI) site in the Argentine Basin (42° S, 42° W).

Drivers of diversity gradients of a highly mobile marine assemblage in a mesoscale seascape

2020 ◽  
Vol 638 ◽  
pp. 149-164
Author(s):  
GM Svendsen ◽  
M Ocampo Reinaldo ◽  
MA Romero ◽  
G Williams ◽  
A Magurran ◽  
...  
Keyword(s):  
Environmental Gradients ◽  
Regression Tree ◽  
Demersal Fish ◽  
Open Ocean ◽  
Shared Resources ◽  
Thermal Front ◽  
Boosted Regression Tree ◽  
Diversity Gradients ◽  
Α Diversity ◽  
Bottom Depth

With the unprecedented rate of biodiversity change in the world today, understanding how diversity gradients are maintained at mesoscales is a key challenge. Drawing on information provided by 3 comprehensive fishery surveys (conducted in different years but in the same season and with the same sampling design), we used boosted regression tree (BRT) models in order to relate spatial patterns of α-diversity in a demersal fish assemblage to environmental variables in the San Matias Gulf (Patagonia, Argentina). We found that, over a 4 yr period, persistent diversity gradients of species richness and probability of an interspecific encounter (PIE) were shaped by 3 main environmental gradients: bottom depth, connectivity with the open ocean, and proximity to a thermal front. The 2 main patterns we observed were: a monotonic increase in PIE with proximity to fronts, which had a stronger effect at greater depths; and an increase in PIE when closer to the open ocean (a ‘bay effect’ pattern). The originality of this work resides on the identification of high-resolution gradients in local, demersal assemblages driven by static and dynamic environmental gradients in a mesoscale seascape. The maintenance of environmental gradients, specifically those associated with shared resources and connectivity with an open system, may be key to understanding community stability.

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