scholarly journals A two-dimensional nitrogen and carbon flux model in a coastal upwelling region

2002 ◽  
Vol 16 (1) ◽  
pp. 11-1-11-15 ◽  
Author(s):  
Debby Ianson ◽  
Susan E. Allen
Keyword(s):  
Carbon Flux ◽  
Coastal Upwelling ◽  
Two Dimensional ◽  
Flux Model

scholarly journals Sinking rates and ballast composition of particles in the Atlantic Ocean: implications for the organic carbon fluxes to the deep ocean

2009 ◽  
Vol 6 (1) ◽  
pp. 85-102 ◽  
Author(s):  
G. Fischer ◽  
G. Karakaş
Keyword(s):  
Organic Carbon ◽  
Atlantic Ocean ◽  
Sediment Trap ◽  
Carbon Flux ◽  
Coastal Upwelling ◽  
Production Systems ◽  
Deep Ocean ◽  
Biogeochemical Model ◽  
Carbonate Content ◽  
Organic Carbon Flux

Abstract. The flux of materials to the deep sea is dominated by larger, organic-rich particles with sinking rates varying between a few meters and several hundred meters per day. Mineral ballast may regulate the transfer of organic matter and other components by determining the sinking rates, e.g. via particle density. We calculated particle sinking rates from mass flux patterns and alkenone measurements applying the results of sediment trap experiments from the Atlantic Ocean. We have indication for higher particle sinking rates in carbonate-dominated production systems when considering both regional and seasonal data. During a summer coccolithophorid bloom in the Cape Blanc coastal upwelling off Mauritania, particle sinking rates reached almost 570 m per day, most probably due the fast sedimentation of densely packed zooplankton fecal pellets, which transport high amounts of organic carbon associated with coccoliths to the deep ocean despite rather low production. During the recurring winter-spring blooms off NW Africa and in opal-rich production systems of the Southern Ocean, sinking rates of larger particles, most probably diatom aggregates, showed a tendency to lower values. However, there is no straightforward relationship between carbonate content and particle sinking rates. This could be due to the unknown composition of carbonate and/or the influence of particle size and shape on sinking rates. It also remains noticeable that the highest sinking rates occurred in dust-rich ocean regions off NW Africa, but this issue deserves further detailed field and laboratory investigations. We obtained increasing sinking rates with depth. By using a seven-compartment biogeochemical model, it was shown that the deep ocean organic carbon flux at a mesotrophic sediment trap site off Cape Blanc can be captured fairly well using seasonal variable particle sinking rates. Our model provides a total organic carbon flux of 0.29 Tg per year down to 3000 m off the NW African upwelling region between 5 and 35° N. Simple parameterisations of remineralisation and sinking rates in such models, however, limit their capability in reproducing the flux variation in the water column.

Processes of coastal upwelling and carbon flux in the Cariaco Basin

2004 ◽  
Vol 51 (10-11) ◽  
pp. 927-943 ◽  
Author(s):  
Frank Muller-Karger ◽  
Ramon Varela ◽  
Robert Thunell ◽  
Yrene Astor ◽  
Haiying Zhang ◽  
...  
Keyword(s):  
Carbon Flux ◽  
Coastal Upwelling ◽  
Cariaco Basin

scholarly journals Evaluation of a polynya flux model by means of thermal infrared satellite estimates

2011 ◽  
Vol 52 (57) ◽  
pp. 52-60 ◽  
Author(s):  
Thomas Krumpen ◽  
Sascha Willmes ◽  
Miguel Angel Morales Maqueda ◽  
Christian Haas ◽  
Jens A. Hölemann ◽  
...  
Keyword(s):  
Conservation Laws ◽  
Open Water ◽  
Thermal Infrared ◽  
Ice Thickness ◽  
Two Dimensional ◽  
Moderate Resolution ◽  
Flux Model ◽  
Resolution Imaging ◽  
Moderate Resolution Imaging Spectroradiometer ◽  
Ice Production

AbstractWe test the ability of a two-dimensional flux model to simulate polynya events with narrow open-water zones by comparing model results to ice-thickness and ice-production estimates derived from thermal infrared Moderate Resolution Imaging Spectroradiometer (MODIS) observations in conjunction with an atmospheric dataset. Given a polynya boundary and an atmospheric dataset, the model correctly reproduces the shape of an 11 day long event, using only a few simple conservation laws. Ice production is slightly overestimated by the model, owing to an underestimated ice thickness. We achieved best model results with the consolidation thickness parameterization developed by Biggs and others (2000). Observed regional discrepancies between model and satellite estimates might be a consequence of the missing representation of the dynamic of the thin-ice thickening (e.g. rafting). We conclude that this simplified polynya model is a valuable tool for studying polynya dynamics and estimating associated fluxes of single polynya events.

Modifying the Soil and Water Assessment Tool to simulate cropland carbon flux: Model development and initial evaluation

2013 ◽  
Vol 463-464 ◽  
pp. 810-822 ◽  
Author(s):  
Xuesong Zhang ◽  
R. César Izaurralde ◽  
Jeffrey G. Arnold ◽  
Jimmy R. Williams ◽  
Raghavan Srinivasan
Keyword(s):  
Carbon Flux ◽  
Assessment Tool ◽  
Model Development ◽  
Initial Evaluation ◽  
Flux Model ◽  
Water Assessment ◽  
Soil And Water

Processes of coastal upwelling and carbon flux in the Cariaco Basin

2004 ◽  
Vol 51 (10-11) ◽  
pp. 927-943 ◽  
Author(s):  
F MULLERKARGER ◽  
R VARELA ◽  
R THUNELL ◽  
Y ASTOR ◽  
H ZHANG ◽  
...  
Keyword(s):  
Carbon Flux ◽  
Coastal Upwelling ◽  
Cariaco Basin

Remotely sensed soil moisture integration in an ecosystem carbon flux model. The spatial implication

2010 ◽  
pp. 117-136 ◽  
Author(s):  
Willem W. Verstraeten ◽  
Frank Veroustraete ◽  
Wolfgang Wagner ◽  
Tom Van Roey ◽  
Walter Heyns ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Carbon Flux ◽  
Remotely Sensed ◽  
Ecosystem Carbon ◽  
Flux Model
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