Joseki
joseki.accessor¶
Accessor module.
Attributes¶
Classes¶
Joseki accessor. |
Functions¶
Return the average molecular mass of a molecule. |
Module Contents¶
- class joseki.accessor.JosekiAccessor(xarray_obj)[source]¶
Joseki accessor.
- drop_molecules(molecules)[source]¶
Drop molecules from dataset.
- Parameters:
molecules (List[str]) – List of molecules to drop.
- Returns:
Dataset with molecules dropped.
- Return type:
- rescale(factors, check_x_sum=False)[source]¶
Rescale molecules concentration in atmospheric profile.
- Parameters:
- Raises:
ValueError – if
check_x_sumisTrueand the dataset is not valid.- Returns:
Rescaled dataset (new object).
- Return type:
- rescale_to(target, check_x_sum=False)[source]¶
Rescale mole fractions to match target molecular total column densities.
- Parameters:
target (Mapping[str, pint.Quantity | dict | xarray.DataArray]) – Mapping of molecule and target total column density. Total column must be either a column number density [
length^-2], a column mass density [mass * length^-2], a number density at sea level [length^-3], a mass density at sea level [mass * length^-3], a mole fraction at sea level [dimensionless].check_x_sum (bool) – if True, check that mole fraction sums are never larger than one.
- Returns:
Rescaled dataset (new object).
- Return type:
- scaling_factors(target)[source]¶
Compute scaling factor(s) to reach specific target amount(s).
- Parameters:
target (MutableMapping[str, pint.Quantity | dict | xarray.DataArray]) – Mapping of molecule and target amount.
- Raises:
ValueError – If a target amount has dimensions that are not supported.
- Returns:
Mapping of molecule and scaling factors.
- Return type:
Notes
For each molecule in the
targetmapping, the target amount is interpreted, depending on its dimensions (indicated in square brackets), as:a column number density [
length^-2],a column mass density [
mass * length^-2],a number density at sea level [
length^-3],a mass density at sea level [
mass * length^-3],a mole fraction at sea level [
dimensionless]
The scaling factor is then evaluated as the ratio of the target amount with the original amount, for each molecule.
See also
rescale
- validate(check_x_sum=False, ret_true_if_valid=False)[source]¶
Validate atmosphere thermophysical profile dataset schema.
- property air_molar_mass: xarray.DataArray¶
Compute air molar mass as a function of altitude.
- Returns:
Air molar mass.
- Return type:
Notes
The air molar mass is given by:
\[M_{\mathrm{air}} = \frac{ \sum_{\mathrm{M}} x_{\mathrm{M}} \, m_{\mathrm{M}} }{ \sum_{\mathrm{M}} x_{\mathrm{M}} }\]where
\(x_{\mathrm{M}}\) is the mole fraction of molecule M,
\(m_{\mathrm{M}}\) is the molar mass of molecule M.
To compute the air molar mass accurately, the mole fraction of molecular nitrogen (N2), molecular oxygen (O2), and argon (Ar) are required. If these are not present in the dataset, they are computed using the assumption that the mole fraction of these molecules are constant with altitude and set to the following values:
molecular nitrogen (N2): 0.78084
molecular oxygen (O2): 0.209476
argon (Ar): 0.00934
are independent of altitude.
Since nothing guarantees that the mole fraction sum is equal to one, the air molar mass is computed as the sum of the mole fraction weighted molar mass divided by the sum of the mole fraction.
- property air_number_density: xarray.DataArray¶
- Return type:
- property column_mass_density: Dict[str, pint.Quantity]¶
Compute column mass density.
- Returns:
A mapping of molecule and column mass density.
- Return type:
Dict[str, pint.Quantity]
Notes
The column mass density is given by:
\[\sigma_{\mathrm{M}} = N_{\mathrm{M}} \, m_{\mathrm{M}}\]where
\(N_{\mathrm{M}}\) is the column number density of molecule M,
\(m_{\mathrm{M}}\) is the molecular mass of molecule M.
- property column_number_density: Dict[str, pint.Quantity]¶
Compute column number density.
- Returns:
A mapping of molecule and column number density.
- Return type:
Dict[str, pint.Quantity]
Notes
The column number density is given by:
\[N_{\mathrm{M}} = \int n_{\mathrm{M}}(z) \, \mathrm{d} z\]with
\[n_{\mathrm{M}}(z) = x_{\mathrm{M}}(z) \, n(z)\]where
\(z\) is the altitude,
\(x_{\mathrm{M}}(z)\) is the mole fraction of molecule M at altitude \(z\),
\(n(z)\) is the air number density at altitude \(z\),
\(n_{\mathrm{M}}(z)\) is the number density of molecule M at altitude \(z\).
The integration is performed using the trapezoidal rule.
- property is_valid¶
Return
Trueif the dataset complies with the schema, else False.
- property mass_density_at_sea_level: Dict[str, pint.Quantity]¶
Compute mass density at sea level.
- Returns:
A mapping of molecule and mass density at sea level.
- Return type:
Dict[str, pint.Quantity]
- property mass_fraction: xarray.DataArray¶
Extract mass fraction and tabulate as a function of (m, z).
- Returns:
Mass fraction.
- Return type:
- property mole_fraction: xarray.DataArray¶
Extract mole fraction and tabulate as a function of (m, z).
- Returns:
Mole fraction.
- Return type:
- property mole_fraction_at_sea_level: Dict[str, pint.Quantity]¶
Compute mole fraction at sea level.
- Returns:
A mapping of molecule and mole fraction at sea level.
- Return type:
Dict[str, pint.Quantity]
- property number_density: xarray.DataArray¶
Compute number densities for each species as a function of altitude and return them as a data array.
- Return type:
- property number_density_at_sea_level: Dict[str, pint.Quantity]¶
Compute number density at sea level.
- Returns:
A mapping of molecule and number density at sea level.
- Return type:
Dict[str, pint.Quantity]
- joseki.accessor.molecular_mass(m)[source]¶
Return the average molecular mass of a molecule.
- Parameters:
m (str) – Molecule formula.
- Returns:
Average molecular mass.
- Return type:
- joseki.accessor.logger¶