scholarly journals Coastal-ocean uptake of anthropogenic carbon

2016 ◽  
Vol 13 (14) ◽  
pp. 4167-4185 ◽  
Author(s):  
Timothée Bourgeois ◽  
James C. Orr ◽  
Laure Resplandy ◽  
Jens Terhaar ◽  
Christian Ethé ◽  
...  
Keyword(s):  
Coastal Ocean ◽  
Global Ocean ◽  
Biogeochemical Model ◽  
Shelf Area ◽  
Surface Areas ◽  
Anthropogenic Carbon ◽  
The Mean ◽  
Continental Shelf Area ◽  
Global Inventory ◽  
Offshore Transport

Abstract. Anthropogenic changes in atmosphere–ocean and atmosphere–land CO2 fluxes have been quantified extensively, but few studies have addressed the connection between land and ocean. In this transition zone, the coastal ocean, spatial and temporal data coverage is inadequate to assess its global budget. Thus we use a global ocean biogeochemical model to assess the coastal ocean's global inventory of anthropogenic CO2 and its spatial variability. We used an intermediate resolution, eddying version of the NEMO-PISCES model (ORCA05), varying from 20 to 50 km horizontally, i.e. coarse enough to allow multiple century-scale simulations but finer than coarse-resolution models (∼  200 km) to better resolve coastal bathymetry and complex coastal currents. Here we define the coastal zone as the continental shelf area, excluding the proximal zone. Evaluation of the simulated air–sea fluxes of total CO2 for 45 coastal regions gave a correlation coefficient R of 0.8 when compared to observation-based estimates. Simulated global uptake of anthropogenic carbon results averaged 2.3 Pg C yr−1 during the years 1993–2012, consistent with previous estimates. Yet only 0.1 Pg C yr−1 of that is absorbed by the global coastal ocean. That represents 4.5 % of the anthropogenic carbon uptake of the global ocean, less than the 7.5 % proportion of coastal-to-global-ocean surface areas. Coastal uptake is weakened due to a bottleneck in offshore transport, which is inadequate to reduce the mean anthropogenic carbon concentration of coastal waters to the mean level found in the open-ocean mixed layer.

scholarly journals Coastal-ocean uptake of anthropogenic carbon

2016 ◽  
Author(s):  
Timothée Bourgeois ◽  
James C. Orr ◽  
Laure Resplandy ◽  
Christian Ethé ◽  
Marion Gehlen ◽  
...  
Keyword(s):  
Coastal Ocean ◽  
Global Ocean ◽  
Biogeochemical Model ◽  
Temporal Data ◽  
Anthropogenic Carbon ◽  
Ocean Biogeochemical Model ◽  
Data Coverage ◽  
The Mean ◽  
Global Inventory ◽  
Offshore Transport

Abstract. Anthropogenic changes in atmosphere-ocean and atmosphere-land CO2 fluxes have been quantified extensively, but few studies have addressed the connection between land and ocean. In this transition zone, the coastal ocean, spatial and temporal data coverage is inadequate to assess its global budget. Thus we use a global ocean biogeochemical model to assess the coastal ocean's global inventory of anthropogenic CO2 and its spatial variability. We used an intermediate resolution, eddying version of the NEMO-PISCES model (ORCA05), varying from 20 to 50 km horizontally, i.e., coarse enough to allow multiple century-scale simulations but finer than coarse resolution models (~ 200 km), to begin to better resolve coastal bathymetry. Simulated results indicated that the global ocean absorbed 2.3 Pg C yr−1 of anthropogenic carbon during 1993–2012, consistent with previous estimates. Yet only 4.5 % of that (0.10 Pg C yr−1) is absorbed by the global coastal ocean, i.e., less than its 7.5 % proportion of the global ocean surface area. Coastal uptake is weakened due to a bottleneck in offshore transport, which is inadequate to reduce the mean anthropogenic carbon concentration of coastal waters to the mean level found in the open-ocean mixed layer.

scholarly journals Simulation of anthropogenic CO<sub>2</sub> uptake in the CCSM3.1 ocean circulation-biogeochemical model: comparison with data-based estimates

2011 ◽  
Vol 8 (6) ◽  
pp. 10895-10933
Author(s):  
S. Wang ◽  
J. K. Moore ◽  
F. W. Primeau ◽  
S. Khatiwala
Keyword(s):  
Ocean Circulation ◽  
Model Comparison ◽  
Industrial Revolution ◽  
Large Fraction ◽  
Detailed Comparison ◽  
Global Ocean ◽  
Inversion Method ◽  
Biogeochemical Model ◽  
Climate System Model ◽  
Anthropogenic Carbon

Abstract. The global ocean has taken up a large fraction of the CO2 released by human activities since the industrial revolution. Quantifying the oceanic anthropogenic carbon (Cant) inventory and its variability is important for predicting the future global carbon cycle. The detailed comparison of data-based and model-based estimates is essential for the validation and continued improvement of our prediction capabilities. So far, three global estimates of oceanic Cant inventory that are "data-based" and independent of global ocean circulation models have been produced: one based on the ΔC* method, and two are based on reconstructions of the Green function for the surface-to-interior transport, the TTD method and the maximum entropy inversion method (KPH). The KPH method, in particular, is capable of reconstructing the history of Cant inventory through the industrial era. In the present study we use forward model simulations of the Community Climate System Model (CCSM3.1) to estimate the Cant inventory and compare the results with the data-based estimates. We also use the simulations to test several assumptions of the KPH method, including the assumption of constant climate and circulation, which is common to all the data-based estimates. Though the integrated estimates of global Cant inventories are consistent with each other, the regional estimates show discrepancies up to 50 %. The CCSM3 model underestimates the total Cant inventory, in part due to weak mixing and ventilation in the North Atlantic and Southern Ocean. Analyses of different simulation results suggest that key assumptions about ocean circulation and air-sea disequilibrium in the KPH method are generally valid on the global scale, but may introduce significant errors in Cant estimates on regional scales. The KPH method should also be used with caution when predicting future oceanic anthropogenic carbon uptake.

Estuarine–Coastal Interactions

2006 ◽  
Author(s):  
Thomas S. Bianchi
Keyword(s):  
Organic Matter ◽  
High Water ◽  
Coastal Ocean ◽  
Global Ocean ◽  
International Programs ◽  
The European Union ◽  
Fish Catch ◽  
Estuarine Coastal ◽  
Core Project ◽  
Offshore Transport

The coastal ocean is a dynamic region where the rivers, estuaries, ocean, land, and the atmosphere interact (Walsh, 1988; Mantoura et al., 1991; Alongi, 1998; Wollast, 1998). Coastlines extend over an estimated 350,000 km worldwide, and the coastal ocean, typically defined as a region that extends from the high water mark to the shelf break (figure 16.1; Alongi, 1998), covers approximately 7% (26 × 106 km2) of the surface global ocean (Gattuso et al., 1998). Although relatively small in area, this highly productive region (30% of the total net oceanic productivity) supports as much as 90% of the global fish catch (Holligan, 1992). In recent years, the coastal ocean has been recognized for its global importance with both national and international programs such as the Land–Ocean Interactions in the Coastal Zone (LOICZ) program, a subprogram of the International Global Change Program (IGBP) started in 1993 (Pernetta and Milliman, 1995), the European Union coastal core project (European Land–Ocean Interaction Studies, ELOISE) (Cadée et al., 1994), and in the U.S. Shelf Edge Exchange Processes Program (SEEP I and SEEP II) (Walsh et al., 1988; Anderson et al., 1994), the Coastal Ocean Processes (CoOP) program, Ocean Margins Program (OMP), and Land–Margin Ecosystem Research (LMER), to name a few. SEEP I and SEEP II were designed to test the Walsh et al. (1985) hypothesis that increased anthropogenic nutrient supply to the coastal ocean would result in enhanced burial of organic matter in continental margins due to higher offshore export of new productivity in the nearshore waters. While the hypothesis of offshore transport and burial was shown to be valid along certain regions of the eastern U.S. coast, other regions showed a more along-shelf transport (Walsh, 1994). More recent work in the OMP, which revisited some of the objectives of SEEP I and SEEP II, found that the accumulation of organic matter in upper slope sediments was only <1% of the total primary production in the entire continental margin of North Carolina (DeMaster et al., 2002). There are many factors that will ultimately determine if and how much nearshore production is exported offshore from the coastal ocean.

scholarly journals Simulation of anthropogenic CO<sub>2</sub> uptake in the CCSM3.1 ocean circulation-biogeochemical model: comparison with data-based estimates

2012 ◽  
Vol 9 (4) ◽  
pp. 1321-1336 ◽  
Author(s):  
S. Wang ◽  
J. K. Moore ◽  
F. W. Primeau ◽  
S. Khatiwala
Keyword(s):  
Ocean Circulation ◽  
Model Comparison ◽  
Industrial Revolution ◽  
Large Fraction ◽  
Detailed Comparison ◽  
Global Ocean ◽  
Inversion Method ◽  
Biogeochemical Model ◽  
Climate System Model ◽  
Anthropogenic Carbon

Abstract. The global ocean has taken up a large fraction of the CO2 released by human activities since the industrial revolution. Quantifying the oceanic anthropogenic carbon (Cant) inventory and its variability is important for predicting the future global carbon cycle. The detailed comparison of data-based and model-based estimates is essential for the validation and continued improvement of our prediction capabilities. So far, three global estimates of oceanic Cant inventory that are "data-based" and independent of global ocean circulation models have been produced: one based on the Δ C* method, and two that are based on constraining surface-to-interior transport of tracers, the TTD method and a maximum entropy inversion method (GF). The GF method, in particular, is capable of reconstructing the history of Cant inventory through the industrial era. In the present study we use forward model simulations of the Community Climate System Model (CCSM3.1) to estimate the Cant inventory and compare the results with the data-based estimates. We also use the simulations to test several assumptions of the GF method, including the assumption of constant climate and circulation, which is common to all the data-based estimates. Though the integrated estimates of global Cant inventories are consistent with each other, the regional estimates show discrepancies up to 50 %. The CCSM3 model underestimates the total Cant inventory, in part due to weak mixing and ventilation in the North Atlantic and Southern Ocean. Analyses of different simulation results suggest that key assumptions about ocean circulation and air-sea disequilibrium in the GF method are generally valid on the global scale, but may introduce errors in Cant estimates on regional scales. The GF method should also be used with caution when predicting future oceanic anthropogenic carbon uptake.

60 Contact Hand Burns in Children: Still a Major Prevention Need

2020 ◽  
Vol 41 (Supplement_1) ◽  
pp. S39-S40
Author(s):  
Jaclyn M McBride ◽  
Kathleen S Romanowski ◽  
Soman Sen ◽  
Tina L Palmieri ◽  
David G Greenhalgh
Keyword(s):  
Graft Loss ◽  
Dorsal Surface ◽  
Skin Grafting ◽  
Secondary Surgery ◽  
Surface Areas ◽  
Palmar Surface ◽  
The Mean ◽  
Total Body ◽  
Hand Burns ◽  
Palmar Aspect

Abstract Introduction Since toddlers explore with their hands, contact burns continue to be a major pediatric problem. The purpose of this report is to review a pediatric burn unit’s 8-year experience with contact burns of the hand. Methods After IRB approval, a review of pediatric contact hand burns that occurred between 2006–2014 was performed. We examined the causes and outcomes in pediatric contact hand burns in a single pediatric burn program. Results In the 8-year span, 535 children suffered contact burns to the hand (67 per year). The majority suffered hands burns from an oven or stove (120). The other etiologies included burns from a fireplace (76), clothing iron (65), curling or straightening iron (50), and firepit or campfire (46). The mean age at time of injury was 2.62 years old, with a range of 2 months old to18 years old. Male children (339) typically burned their hands more than females (197). Locations of injury included the palmar surface, dorsal surface, fingers tips/thumb, wrist or a combination of several different areas. Most children burned the palmar aspect of their hand (384) compared to the dorsal aspect (61). These burns typically cover small total body surface areas (mean 1.08% TBSA), with only 2% of burns comprising &gt;5% TBSA. Approximately, 84% of these patients did not need surgery, but 86 (16%) had skin grafting (usually full-thickness) and 26% needed a secondary surgery. Of those that needed more than two, the average number of procedures was 3.6. Approximately 4.1% of patients needed a tertiary surgery. Causes for tertiary surgeries included contractures and graft loss. Out of twenty-two patients that needed a third surgery, 59% were due to graft loss and 41% were due to contractures. Conclusions Contact burns to the hand continue to be a major problem for toddlers. Children are most likely to burn themselves on an oven or stove, fireplace, clothing iron or curling/straightening iron. The palmar surface of the hand is the most likely site. While most children do not require surgery, approximately 16% require grafting. A significant number of those patients need reconstructive surgery. Clearly, current prevention efforts have failed to reduce these injuries. Applicability of Research to Practice Palm burns are common in young children. Efforts should focus on preventing these injuries.

Effects of light and phosphorus on summer DMS dynamics in subtropical waters using a global ocean biogeochemical model

2016 ◽  
Vol 13 (2) ◽  
pp. 379 ◽  
Author(s):  
Italo Masotti ◽  
Sauveur Belviso ◽  
Laurent Bopp ◽  
Alessandro Tagliabue ◽  
Eva Bucciarelli
Keyword(s):  
General Circulation ◽  
North Atlantic Ocean ◽  
Model Simulation ◽  
Global Ocean ◽  
Longitudinal Distribution ◽  
Biogeochemical Model ◽  
Relative Role ◽  
Sargasso Sea ◽  
Ecological Processes ◽  
Climatological Data

Environmental context Models are needed to predict the importance of the changes in marine emissions of dimethylsulfide (DMS) in response to ocean warming, increased stratification and acidification, and to evaluate the potential effects on the Earth’s climate. We use complementary simulations to further our understanding of the marine cycle of DMS in subtropical waters, and show that a lack of phosphorus may exert a more important control on surface DMS concentrations than an excess of light. Abstract The occurrence of a summer DMS paradox in the vast subtropical gyres is a strong matter of debate because approaches using discrete measurements, climatological data and model simulations yielded contradictory results. The major conclusion of the first appraisal of prognostic ocean DMS models was that such models need to give more weight to the direct effect of environmental forcings (e.g. irradiance) on DMS dynamics to decouple them from ecological processes. Here, the relative role of light and phosphorus on summer DMS dynamics in subtropical waters is assessed using the ocean general circulation and biogeochemistry model NEMO-PISCES in which macronutrient concentrations were restored to monthly climatological data values to improve the representation of phosphate concentrations. Results show that the vertical and temporal decoupling between chlorophyll and DMS concentrations observed in the Sargasso Sea during the summer months is captured by the model. Additional sensitivity tests show that the simulated control of phosphorus on surface DMS concentrations in the Sargasso Sea is much more important than that of light. By extending the analysis to the whole North Atlantic Ocean, we show that the longitudinal distribution of DMS during summer is asymmetrical and that a correlation between the solar radiation dose and DMS concentrations only occurs in the Sargasso Sea. The lack of a widespread summer DMS paradox in our model simulation as well as in the comparison of discrete and climatological data could be due to the limited occurrence of phosphorus limitation in the global ocean.

Estimating Global Ocean Heat Content Changes in the Upper 1800 m since 1950 and the Influence of Climatology Choice*

2014 ◽  
Vol 27 (5) ◽  
pp. 1945-1957 ◽  
Author(s):  
John M. Lyman ◽  
Gregory C. Johnson
Keyword(s):  
Heat Content ◽  
Ocean Heat Content ◽  
Global Ocean ◽  
Ocean Temperature ◽  
Vertical Separation ◽  
Ocean Heat Uptake ◽  
Expendable Bathythermograph ◽  
Heat Uptake ◽  
The Mean

Abstract Ocean heat content anomalies are analyzed from 1950 to 2011 in five distinct depth layers (0–100, 100–300, 300–700, 700–900, and 900–1800 m). These layers correspond to historic increases in common maximum sampling depths of ocean temperature measurements with time, as different instruments—mechanical bathythermograph (MBT), shallow expendable bathythermograph (XBT), deep XBT, early sometimes shallower Argo profiling floats, and recent Argo floats capable of worldwide sampling to 2000 m—have come into widespread use. This vertical separation of maps allows computation of annual ocean heat content anomalies and their sampling uncertainties back to 1950 while taking account of in situ sampling advances and changing sampling patterns. The 0–100-m layer is measured over 50% of the globe annually starting in 1956, the 100–300-m layer starting in 1967, the 300–700-m layer starting in 1983, and the deepest two layers considered here starting in 2003 and 2004, during the implementation of Argo. Furthermore, global ocean heat uptake estimates since 1950 depend strongly on assumptions made concerning changes in undersampled or unsampled ocean regions. If unsampled areas are assumed to have zero anomalies and are included in the global integrals, the choice of climatological reference from which anomalies are estimated can strongly influence the global integral values and their trend: the sparser the sampling and the bigger the mean difference between climatological and actual values, the larger the influence.

scholarly journals Marine productivity response to Heinrich events: a model-data comparison

2012 ◽  
Vol 8 (5) ◽  
pp. 1581-1598 ◽  
Author(s):  
V. Mariotti ◽  
L. Bopp ◽  
A. Tagliabue ◽  
M. Kageyama ◽  
D. Swingedouw
Keyword(s):  
North Atlantic ◽  
General Circulation ◽  
Circulation Model ◽  
Global Ocean ◽  
Biogeochemical Model ◽  
Heinrich Events ◽  
The North ◽  
Heinrich Event ◽  
The North Atlantic ◽  
Marine Productivity

Abstract. Marine sediments records suggest large changes in marine productivity during glacial periods, with abrupt variations especially during the Heinrich events. Here, we study the response of marine biogeochemistry to such an event by using a biogeochemical model of the global ocean (PISCES) coupled to an ocean-atmosphere general circulation model (IPSL-CM4). We conduct a 400-yr-long transient simulation under glacial climate conditions with a freshwater forcing of 0.1 Sv applied to the North Atlantic to mimic a Heinrich event, alongside a glacial control simulation. To evaluate our numerical results, we have compiled the available marine productivity records covering Heinrich events. We find that simulated primary productivity and organic carbon export decrease globally (by 16% for both) during a Heinrich event, albeit with large regional variations. In our experiments, the North Atlantic displays a significant decrease, whereas the Southern Ocean shows an increase, in agreement with paleo-productivity reconstructions. In the Equatorial Pacific, the model simulates an increase in organic matter export production but decreased biogenic silica export. This antagonistic behaviour results from changes in relative uptake of carbon and silicic acid by diatoms. Reasonable agreement between model and data for the large-scale response to Heinrich events gives confidence in models used to predict future centennial changes in marine production. In addition, our model allows us to investigate the mechanisms behind the observed changes in the response to Heinrich events.

scholarly journals Carbon cycling in the North American coastal ocean: A synthesis

2018 ◽  
Author(s):  
Katja Fennel ◽  
Simone Alin ◽  
Leticia Barbero ◽  
Wiley Evans ◽  
Timotheé Bourgeois ◽  
...  
Keyword(s):  
Ocean Acidification ◽  
North American ◽  
Inorganic Carbon ◽  
Co2 Flux ◽  
Carbon Fluxes ◽  
Coastal Ocean ◽  
Open Ocean ◽  
The Arctic ◽  
The North ◽  
Anthropogenic Carbon

Abstract. A quantification of carbon fluxes in the coastal ocean and across its boundaries, specifically the air-sea, land-to-coastal-ocean and coastal-to-open-ocean interfaces, is important for assessing the current state and projecting future trends in ocean carbon uptake and coastal ocean acidification, but is currently a missing component of global carbon budgeting. This synthesis reviews recent progress in characterizing these carbon fluxes with focus on the North American coastal ocean. Several observing networks and high-resolution regional models are now available. Recent efforts have focused primarily on quantifying net air-sea exchange of carbon dioxide (CO2). Some studies have estimated other key fluxes, such as the exchange of organic and inorganic carbon between shelves and the open ocean. Available estimates of air-sea CO2 flux, informed by more than a decade of observations, indicate that the North American margins act as a net sink for atmospheric CO2. This net uptake is driven primarily by the high-latitude regions. The estimated magnitude of the net flux is 160 ± 80 Tg C/y for the North American Exclusive Economic Zone, a number that is not well constrained. The increasing concentration of inorganic carbon in coastal and open-ocean waters leads to ocean acidification. As a result conditions favouring dissolution of calcium carbonate occur regularly in subsurface coastal waters in the Arctic, which are naturally prone to low pH, and the North Pacific, where upwelling of deep, carbon-rich waters has intensified and, in combination with the uptake of anthropogenic carbon, leads to low seawater pH and aragonite saturation states during the upwelling season. Expanded monitoring and extension of existing model capabilities are required to provide more reliable coastal carbon budgets, projections of future states of the coastal ocean, and quantification of anthropogenic carbon contributions.

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