skyscapes.physical_model.exojax.components.mmr_profile#

Mass-mixing-ratio profiles for atmospheric species.

Each species in a MolecularSpecies tuple carries one of these profile components, replacing the previous “scalar mmr per planet” representation. Different molecules need different altitude variations:

Well-mixed gases (N2, O2, CO2, CH4 in our pressure range): use ConstantMmr – same mmr at every layer.

O3 is concentrated in the stratosphere with column ~10x larger than a uniformly-mixed model would assume: use StratosphericPeakMmr (Gaussian in log-pressure).

H2O has a sharp cold-trap drop at the tropopause (~0.1 bar) where temperatures fall below ~200 K: use TroposphericMmr (sigmoid-smoothed step in log-pressure).

The profile contract is just evaluate(pressure) -> (n_layers,) mmr. Layer pressures come from the rt_engine; each component returns the per-layer mass-mixing ratio.

Classes#

`AbstractMmrProfile`	Per-species mass-mixing-ratio profile evaluated at layer pressures.
`ConstantMmr`	Well-mixed gas: constant mmr at every layer.
`StratosphericPeakMmr`	Gaussian-in-log-pressure peak; canonical for O3.
`TroposphericMmr`	Constant below a step pressure, drops sharply above; canonical for H2O.

Module Contents#

class skyscapes.physical_model.exojax.components.mmr_profile.AbstractMmrProfile[source]#

Bases: equinox.Module

Per-species mass-mixing-ratio profile evaluated at layer pressures.

abstractmethod evaluate(pressure)[source]#

Return shape (n_layers,) mmr values at the layer pressures.

Parameters:: pressure (jaxtyping.Array)
Return type:: jaxtyping.Array

class skyscapes.physical_model.exojax.components.mmr_profile.ConstantMmr[source]#

Bases: AbstractMmrProfile

Well-mixed gas: constant mmr at every layer.

Use for gases with chemical lifetimes longer than mixing timescales in the modelled pressure range (CO2, CH4, O2, N2, etc. in troposphere + lower stratosphere).

Attributes:: log_mmr: Log10 mass-mixing ratio, shape (K,) (per planet).

log_mmr: jaxtyping.Array#

evaluate(pressure)[source]#

Return 10**log_mmr broadcast to pressure.shape.

Parameters:: pressure (jaxtyping.Array)
Return type:: jaxtyping.Array

class skyscapes.physical_model.exojax.components.mmr_profile.StratosphericPeakMmr[source]#

Bases: AbstractMmrProfile

Gaussian-in-log-pressure peak; canonical for O3.

mmr(P) = 10**log_peak_mmr * exp(-0.5 * ((log10(P) - log_peak_pressure_bar) / log_sigma_decades)**2).

For Earth’s O3: log_peak_pressure_bar = log10(0.01) = -2 (10 mbar, ~30 km altitude), log_sigma_decades = 0.5.

Attributes:: log_peak_mmr: Log10 of the peak mmr, shape (K,). log_peak_pressure_bar: Log10 pressure [bar] at peak, (K,). log_sigma_decades: Gaussian width in log10-pressure, (K,).

log_peak_mmr: jaxtyping.Array#

log_peak_pressure_bar: jaxtyping.Array#

log_sigma_decades: jaxtyping.Array#

evaluate(pressure)[source]#

Gaussian peak in log-pressure.

Parameters:: pressure (jaxtyping.Array)
Return type:: jaxtyping.Array

class skyscapes.physical_model.exojax.components.mmr_profile.TroposphericMmr[source]#

Bases: AbstractMmrProfile

Constant below a step pressure, drops sharply above; canonical for H2O.

Uses a sigmoid in log-pressure for smooth transition (differentiable for HMC retrievals). For Earth’s H2O: tropospheric ~3e-3 below 0.1 bar, ~3e-6 above.

Attributes:: log_mmr_below: Log10 mmr at high pressure (below cold trap), (K,). log_mmr_above: Log10 mmr at low pressure (above cold trap), (K,). log_pressure_step_bar: Log10 transition pressure [bar], (K,). log_transition_width_decades: Width of the sigmoid transition

in log10-pressure, (K,). Smaller = sharper step.

log_mmr_below: jaxtyping.Array#

log_mmr_above: jaxtyping.Array#

log_pressure_step_bar: jaxtyping.Array#

log_transition_width_decades: jaxtyping.Array#

evaluate(pressure)[source]#

Sigmoid step in log-pressure.

Parameters:: pressure (jaxtyping.Array)
Return type:: jaxtyping.Array