Consulta: subjectFacets:"Carbonate system"
Registros recuperados: 6
Data/hora: 09/06/2024 15:47:06

Carbonate system properties and anthropogenic carbon inventory in the Algerian Basin during SOMBA cruise (2014): Acidification estimate
Provedor de dados: 5
Autores: Keraghel, Mehdia Asma; Louanchi, Ferial; Zerrouki, Mohamed; Kaci, Malik Ait; Aït-ameur, Nadira; Labaste, Matthieu; Legoff, Hervé; Taillandier, Vincent; Harid, Romaissa; Mortier, Laurent.
Recent studies have provided a better understanding of carbonate system parameters and their spatial and temporal variability in several areas of the Mediterranean Sea. This study uses a new dataset that covered the entire Algerian Basin during the summer of 2014 (SOMBA cruise) to describe the distribution of carbonate system parameters. The findings show that almost the entire basin was a source of CO2 to the atmosphere during the studied period. Besides the well-known TrOCA (Tracer combining Oxygen, Carbon and total Alkalinity) approach, the study proposes new parametrization for the standard back calculation method to assess the anthropogenic carbon concentration. The results of both approaches yield similar distributions and concentration ranges...
Tipo: Text
Palavras-chave: Algerian Basin; Carbonate system; Anthropogenic carbon inventory; Acidification; Mesoscale activity.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00615/72729/71829.pdf

The annual and seasonal variability of the carbonate system in the Bay of Brest (Northwest Atlantic Shelf, 2008–2014)
Provedor de dados: 5
Autores: Salt, Lesley A.; Beaumont, L.; Blain, S.; Bucciarelli, E.; Grossteffan, E.; Guillot, A.; L'Helguen, S.; Merlivat, L.; Repecaud, Michel; Quemener, Loic; Rimmelin-maury, P.; Treguer, P.; Bozec, Y.
From 2008 to 2014, the MAREL-Iroise buoy, located in the Bay of Brest, collected high-frequency measurements of partial pressure of CO2 (pCO2) and ancillary hydrographic parameters, in conjunction with a comprehensive sampling regime of two additional carbonate system variables total alkalinity (AT), and dissolved inorganic carbon (DIC). Biological processes drive variations in AT and DIC throughout the year, except in winter, when primary production is negligible and large freshwater inputs occur. Annually, the Bay of Brest generally behaves as a source of CO2 to the atmosphere (0.14 ± 0.20 mol C m− 2 yr− 1), showing inter-annual variability significantly linked to annual net community production (NCP). The presence of a large community of benthic filter...
Tipo: Text
Palavras-chave: Bay of Brest; Carbonate system; Dissolved inorganic carbon; Total alkalinity.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00350/46157/45855.pdf

Dynamic storage of glacial CO2 in the Atlantic Ocean revealed by boron [CO32-] and pH records
Provedor de dados: 5
Autores: Chalk, T. B.; Foster, G. L.; Wilson, P. A.
The origin and carbon content of the deep water mass that fills the North Atlantic Basin, either Antarctic Bottom Water (AABW) or North Atlantic Deep Water (NADW) is suggested to influence the partitioning of CO2 between the ocean and atmosphere on glacial-interglacial timescales. Fluctuations in the strength of Atlantic meridional overturning circulation (AMOC) have also been shown to play a key role in global and regional climate change on timescales from annual to millennial. The North Atlantic is an important and well-studied ocean basin but many proxy records tracing ocean circulation in this region over the last glacial cycle are challenging to interpret. Here we present new B/Ca-[CO32-] and boron isotope-pH data from sites spanning the North...
Tipo: Text
Palavras-chave: Boron; Geochemistry; Palaeoceanography; Carbonate system; Glacial; Atlantic.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00496/60812/64631.pdf

Le système des carbonates influencé par la diagenèse précoce dans les sédiments côtiers méditerranéens en lien avec l’acidification des océans
Provedor de dados: 5
Autores: Rassmann, Jens.
Continental shelves are key regions for the global carbon cycle and particularly exposed to ocean acidification. A large part of organic matter (OM) of continental and marine origin is mineralized in estuarine sediments following oxic and anoxic pathways. This mineralization produces dissolved inorganic carbon (DIC) leading to acidification of the bottom waters. Anoxic mineralization can produce total alkalinity (TA) that can contribute to buffer bottom water pH and increase the CO2 storage capacity of seawater. Measurements in the sediments of the Rhone River prodelta showed that anoxic mineralization, especially sulfate reduction, are the major pathways of OM mineralization and create high DIC and TA fluxes. Land derived OM is mineralized close to the...
Tipo: Text
Palavras-chave: Carbonate system; Early diagenesis; Mineralization; Pelagic-bentic fluxes; Rhone prodelta; Ocean acidification.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00659/77076/78398.pdf

Estimates of Water-Column Nutrient Concentrations and Carbonate System Parameters in the Global Ocean: A Novel Approach Based on Neural Networks
Provedor de dados: 5
Autores: Sauzede, Raphaelle; Claustre, Hervé; Bittig, Henry; Pasqueron De Fommervault, Orens; Gattuso, Jean-pierre; Legendre, Louis; Johnson, Kenneth S.
A neural network-based method (CANYON: CArbonate system and Nutrients concentration from hYdrological properties and Oxygen using a Neural-network) was developed to estimate water-column biogeochemically relevant variables in the Global Ocean. These are the concentrations of 3 nutrients [nitrate (NO3−), phosphate (PO43−) and silicate (Si(OH)4)] and 4 carbonate system parameters [total alkalinity (AT), dissolved inorganic carbon (CT), pH (pHT) and partial pressure of CO2 (pCO2)], which are estimated from concurrent in situ measurements of temperature, salinity, hydrostatic pressure and oxygen (O2) together with sampling latitude, longitude and date. Seven neural-networks were developed using the GLODAPv2 database, which is largely representative of the...
Tipo: Text
Palavras-chave: Neural network; Nutrients; Carbonate system; Global ocean; GLODAPv2 database; Profiling floats.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00383/49467/49952.pdf

When can ocean acidification impacts be detected from decadal alkalinity measurements?
Provedor de dados: 5
Autores: Carter, B. R.; Frolicher, T. L.; Dunne, J. P.; Rodgers, K. B.; Slater, R. D.; Sarmiento, J. L.
We use a large initial condition suite of simulations (30 runs) with an Earth system model to assess the detectability of biogeochemical impacts of ocean acidification (OA) on the marine alkalinity distribution from decadally repeated hydrographic measurements such as those produced by the Global Ship-Based Hydrographic Investigations Program (GO-SHIP). Detection of these impacts is complicated by alkalinity changes from variability and long-term trends in freshwater and organic matter cycling and ocean circulation. In our ensemble simulation, variability in freshwater cycling generates large changes in alkalinity that obscure the changes of interest and prevent the attribution of observed alkalinity redistribution to OA. These complications from...
Tipo: Text
Palavras-chave: Alkalinity; Ocean acidification; Trend detection; Repeat hydrography; Carbon cycle; Carbonate system.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00383/49419/49860.pdf