Christian Stranne
This dataset contains selected model output for numerical simulations of future climate warming-induced seafloor methane escape from dissociating marine gas hydrates. Data were generated with the numerical gas hydrate model TOUGH+Hydrate with additional geomechanical and geochemical modules included.
When the ocean warms, "frozen methane" known as methane hydrate that are buried in the sediments may start to melt (or dissociate).
The data provided here are derived from numerical model simulations of hydrate-bearing sediments and how they evolve over time as the seafloor temperature increases. These simulations enable us to investigate how much methane gas that are emitted from the seafloors for a given warming scenario, and we can estimate how much of the methane that is being oxidized within the sediments through a microbially mediated process known as anaerobic oxidation of methane (AOM).
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Citation
Christian Stranne (2022) Selected model output from numerical simulations of future climate warming-induced seafloor methane escape. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/stranne-2022-methane-1
References
Stranne C, O’Regan M, Hong W-L, Brüchert V, Ketzer M, Thornton BF, Jakobsson M (2022) Anaerobic oxidation has a minor effect on mitigating seafloor methane emissions from gas hydrate dissociation. Commun Earth Environ 3:163. https://doi.org/10.1038/s43247-022-00490-x
Data description
The dataset contains selected model output for numerical simulations of future climate warming-induced seafloor methane escape from dissociating marine gas hydrates. Data were generated with the numerical gas hydrate model "TOUGH+Hydrate" with additional geomechanical and AOM modules included.
The dataset contains three subsets of data, which are used in figures in the study by Stranne et al. (2022). File names reflect the relevant figures.
Figure 3
Files with names starting with fig3 contain data describing the evolution of methane gas saturation within the sediment column for three different permeabilities (10⁻¹⁷ m⁻², 10⁻¹⁵‧⁵ m⁻², 10⁻¹⁴ m⁻²) (fig3b, fig3d, fig3f). Also corresponding evolution of the cumulative anaerobic oxidation of methane and the cumulative seafloor methane escape are available (10⁻¹⁷ m⁻², 10⁻¹⁵‧⁵ m⁻², 10⁻¹⁴ m⁻²) (fig3c, fig3e, fig3g).
Figure 4
Files with names starting with fig4 contain data describing the equilibrium and actual sulfate-methane transition zone depths, the seafloor methane flux, the anaerobic oxidation of methane, the instantaneous and cumulative AOM efficiencies, all as functions of time. These data are for low permeability sediments (10⁻¹⁷ m⁻²).
Figure 5
Files with names starting with fig5 contain data describes the cumulative AOM filter efficiencies as a function of permeability for 100 years into the simulation (fig5a) and for 200 years into the simulation (fig5c). Also included are data describing the cumulative seafloor methane escape for two cases (base case and without AOM) as a function of permeability for 100 years into the simulation (fig5b) and for 200 years into the simulation (fig5d).
All files in this dataset are space-delimited ascii text files.
Figure 3 (13 files, total of ~300 MB)
- fig3a.asc - two columns (1: time [years], 2: seafloor temperature [°C])
- fig3b_T.asc - 144x1011 matrix (time [years] for the fig3b_GAS.asc matrix)
- fig3b_Z.asc - 144x1011 matrix (depth below seafloor [m] for the fig3b_GAS.asc matrix)
- fig3b_GAS.asc - 144x1011 matrix (gas saturation [%])
- fig3c.asc - three columns (1: time [years], 2: cumulative CH₄ flux [kg/m²])
- fig3d_T.asc - 144x1549 matrix (time [years] for the fig3d_GAS.asc matrix)
- fig3d_Z.asc - 144x1549 matrix (depth below seafloor [m] for the fig3d_GAS.asc matrix)
- fig3d_GAS.asc - 144x1549 matrix (gas saturation [%])
- fig3e.asc - three columns (1: time [years], 2: cumulative CH₄ flux [kg/m²])
- fig3f_T.asc - 144x39022 matrix (time [years] for the fig3f_GAS.asc matrix)
- fig3f_Z.asc - 144x39022 matrix (depth below seafloor [m] for the fig3f_GAS.asc matrix)
- fig3f_GAS.asc - 144x39022 matrix (gas saturation [%])
- fig3g.asc - three columns (1: time [years], 2: cumulative CH₄ flux [kg/m²])
Figure 4 (3 files, total of ~20 MB)
- fig4a.asc - three columns (1: time [years], 2: equilibrium SMT depth [m], 3: actual SMT depth [m])
- fig4b.asc - three columns (1: time [years], 2: AOM [mmol/m²/day], 3: CH₄ flux [mmol/m²/day])
- fig4c.asc - three columns (1: time [years], 2: instantaneous AOM efficiency [%], 3: cumulative AOM efficiency [%])
Figure 5 (4 files, total of ~2 kB)
- fig5a.asc - two columns (1: log₁₀ permeability [m⁻²], 2: cumulative filter efficiency [%])
- fig5b.asc - three columns (1: log₁₀ permeability [m⁻²], 2: Case A cumulative CH₄ escape [kg/m²], 3: Case E cumulative CH₄ escape [kg/m²])
- fig5c.asc - two columns (1: log₁₀ permeability [m⁻²], 2: cumulative filter efficiency [%])
- fig5d.asc - three columns (1: log₁₀ permeability [m⁻²], 2: Case A cumulative CH₄ escape [kg/m²], 3: Case E cumulative CH₄ escape [kg/m²])