DOI: 10.5281/zenodo.16912179
title: Carbon Fluxes, Net Burial (sedimentation) and Carbon Inventories in th German License Area of the Clarion Clipperton Zone derived from Sensitivy Experiments with FABM-MOPS coupled to 1D GOTM model

description: This dataset contains carbon fluxes and inventories of sensitivity eperiments of sediment impact processes in FABM-MOPS coupled to 1D-GOTM by postprocessing of mostly phosphorus-based variables.

Dataset for the deliverable 5.2 of the OceanICU Horizon Europe project.

 

FABM-MOPS model runs

MOPS (Model of Oceanic Pelagic Stoichiometry) is a biogeochemical model that describes the cycling of nutrients, phytoplankton, zooplankton, detritus and dissolved organic matter as tracers with phosphorus as the core element (Kriest & Oschlies, 2015). It was used here as an implemented member biogeochemical model within FABM (The Framework for Aquatic Biogeochemical Models; Bruggeman & Bolding, 2014) and therein coupled to the 1D GOTM (General Ocean Turbulent Model) as a physical host-model.

The main aim here is the simulation of scenarios for impacts of waste sediment material injected into different water depths and times in order to identify respective model parameter sensitivities affecting carbon production, remineralization and export to the seafloor. The experiments were carried out for the location of the German PMN license area of the BGR (117.03W; 11.93N) in the Clarion-Clipperton Zone in the NE equatorial Pacific.

Five different impact processes were implemented in MOPS in order to assess their effects by increased sediment loads in the water column: (1) increased light attenuation coefficient, K_SED, impacting growth of phytoplankton; (2) a reduced maximum grazing rate of zooplankton species, μ_ZOO, being able to discriminate nutrients from sediment particles, but leading to more difficult access to nutrients or escape ractions; (3) a reduced food assimilation rate of zooplankton, ε_ZOO, eating everything (e.g. nutritional values are decreased, clogging of gut tract); (4) a decreased density-dependent loss rate of zooplankton, κ_ZOO, representing the effect on higher-trophic level fauna (e.g. fish); and (5) an increased zooplankton mortality, λ_ZOO, due to potential toxicity of particles and stress effects.

The following parameter set was used in the sensitivity experiments. 




Experiment         \Parameter
ctl
g1
g2
a1
a2
f1
f2
m1
m2
g1*
g2*
a1*
a2*
f1*
f2*
m1*
m2*


K_SED
0.0425
 
 
 
 
 
 
 
 
0
0
0
0
0
0
0
0


μ_ZOO
1
0.5
0
 
 
 
 
 
 
0.5
0
 
 
 
 
 
 


ϵ_ZOO
1
 
 
0.5
0
 
 
 
 
 
 
0.5
0
 
 
 
 


κ_ZOO
1
 
 
 
 
0.5
0
 
 
 
 
 
 
0.5
0
 
 


λ_ZOO
1
 
 
 
 
 
 
1.5
2.0
 
 
 
 
 
 
1.5
2.0




 

The table gives an overview of the parameter settings of the sensitivity experiments: a "standard" set of parameters as control (ctl, kept unaltered in other experiments if not stated otherwise); each experiment label denote the different processes: g = grazing; a = assimilation, f = fish / higher-trophic fauna; m = mortality, with the respective parameter changes. For comparison, the set of experiments was run with and without the effect of reduced light attenuation (the latter indicated by * symbol: K_SED=0).

This parameter set was used in sensitivity experiments for the following sediment injection depths and times:



5 injection depths:   65m, 225m, 1150m, 2450m, 4025m

5 injection times:     1w, 4w, 8w, 26w, 52w


The sediment injection start was arbitrarily chosen to be May 2018 with enough time of more than 4 years for the model to balance from the initial conditions.

In addition, a reference experiment without sediment injection was run.

Dataset description

The NetCDF dataset Carbon_Data_2014-2023_sensitivity_impact_processes-sediment_injections_2018_05-BGR-FABM_MOPS_GOTM.nc contains the calculated carbon fluxes and inventories that were computed from the model results as weekly means.

Variables



Carbon Fluxes (unit [kgm−2s−1])



Primary Production PP: phytoplankton growth phy_f1 converted by C:P-ratio of 117.0 and then depth-integrated

(Gravitational) Carbon Fluxes at 100m, 1000m, 2000m F100, F1000, F2000: detritus flux det_f8 at each level and converted by C:P-ratio of 117.0

(Bottom) Carbon Burial: detritus burial det_burial converted by C:P-ratio of 117.0



Carbon Inventories between 0m-100m, 100m-200m, 200m-1000m, 1000m-2000m and >2000m (unit [kg m−2])



Particulate Organic Carbon POC 0-100, POC 0-100, POC 100-200, POC 200-1000, POC 1000-2000, POC >2000: detritus concentration det_c for each depth range multiplied by cell thickness h and converted by C:P-ratio of 117.0, then integrated over depth.

Dissolved Organic Carbon DOC 0-100, DOC 0-100, DOC 100-200, DOC 200-1000, DOC 1000-2000, DOC >2000: dissolved organic phosphorus dop_c for each depth range multiplied by cell thickness h and converted by C:P-ratio of 117.0, then integrated over depth.

Dissolved Inorganic Carbon DIC 0-100, DIC 0-100, DIC 100-200, DIC 200-1000, DIC 1000-2000, DIC >2000: dissolved inorganic carbon carbon_c for each depth range multiplied by cell thickness h, then integrated over depth.




Coordinates



time: time series of the dates for the weekly means in days since 2014-01-05 00:00:00 (proleptic gregorian)

lon, lat: longitude and latitude of experiment location in BGR license area

exp: experiment names for each experiment



sensitivity experiment: syntax {injection_depth}_{injection_time}_{sensitivity_experiment}, as an example sensitivity experiment f2 for sediment injection at 65m for 8 weeks it would be 65m_8w_f2 (see list above);



attention: experiments without sediment attenuation (KSED=0) have the suffixes _att0, i.e. the example f2* for previous scenario would be 65m_8w_f2_att0



reference experiment: simply reference




Funding Acknowledgement

This work was co-funded by the European Union under grant agreement no. 101083922 (OceanICU) and UK Research and Innovation (UKRI) under the UK government’s Horizon Europe funding guarantee [grant number 10054454, 10063673, 10064020, 10059241, 10079684, 10059012, 10048179]. The views, opinions and practices used to produce this dataset are however those of the author(s) only and do not necessarily reflect those of the European Union or European Research Executive Agency. Neither theEuropean Union nor the granting authority can be held responsible for them.