Biological Carbon Pump — Depth-Time Flux Diagram

Ocean Column Controls

Primary production 1.20 mol C/m²/day

Particle sinking speed 80 m/day

Water temperature 8 °C

Simulation speed 6 days/s

Live Carbon Flux

Export flux @ 100 m

–

Flux @ seafloor 1000 m

–

Sequestration efficiency (seafloor ÷ surface production)

0.0%

Remineralization rate k

–

e-folding depth

–

How it works

This is a 2D depth–time (Hovmöller) view of the same biological pump: instead of tracking individual sinking particles in 3D space, a 1D column of concentration cells C(z) spanning 0–1000 m is stepped forward with an explicit finite-volume advection–decay scheme,

∂C/∂t = −∂(vC)/∂z − k·C
F(z) = v·C(z)                          (diagnostic flux)
k(T)  = k₀ · Q₁₀^((T − T_ref)/10)       [Q₁₀ ≈ 2, T_ref = 0 °C]

with a fixed top boundary flux equal to the primary production rate P₀. At steady state this PDE analytically reduces to the same exponential attenuation law used by the 3D model, F(z) = P₀·exp(−k·z/v), which the right-hand profile plot overlays as a dashed reference curve against the live simulated flux — the two should overlap once the column reaches equilibrium (a few hundred simulated days after a slider change).

Left panel — a scrolling depth (vertical) vs. simulated-time (horizontal) heatmap: brighter green = fresh carbon-rich water, dark brown = remineralized/exhausted.
Right panel — the instantaneous flux-vs-depth profile straight out of the grid, i.e. what a string of sediment traps at every depth would read right now.
Sequestration efficiency — simulated seafloor flux (z=1000 m) divided by surface production, read directly off the grid, not assumed.

Fresh marine snow Remineralized / decayed

Biological Carbon Pump — Depth-Time Flux Diagram (2D)