a) Simulated air-ice CO₂ fluxes (mmol m⁻² d⁻¹) for runs Loose-D_diff (grey, where D_diff = 24 10⁻⁹ m² s⁻¹), No-bub (green, where R^bub = 0% h⁻¹ and D_diff = 0.97 10⁻⁹ m² s⁻¹) and Low-z_BL (dark blue in dash, where z_BL = 0.05 µm). The three curves for runs Loose-D_diff, No-bub and Low-z_BL are confounded on the plot. Observed CO₂ fluxes are given in blue.

b) Simulated air-ice CO₂ fluxes (mmol m⁻² d⁻¹) for runs No-ikaite (dark red, where there is no ikaite precipitation) and 20-layers (dark blue, where the number layers of ice was set to 20 instead of 10). Observed CO₂ fluxes are given in blue.

c) Simulated air-ice CO₂ fluxes (mmol m⁻² d⁻¹) for runs CTRL (in black), Low-bub (grey, where R^bub = 1% h⁻¹), High-bub (cyan, where R^bub = 20% h⁻¹) and Moreau-bub (dark grey, R^bub = 0.1% h⁻¹). Observed CO₂ fluxes (mmol m⁻² d⁻¹) are given in blue.