easyclimate.interp.vinth2p

Interpolates Community Atmosphere Model (CAM) or Community Earth System Model (CESM) hybrid coordinates to pressure coordinates

See also

Functions

interp_vinth2p_dp(→ xarray.DataArray)

Interpolate atmospheric data from Community Atmosphere Model (CAM) hybrid sigma-pressure coordinates to pressure levels.

interp_vinth2p_ecmwf(→ xarray.DataArray)

Interpolate atmospheric data from Community Atmosphere Model (CAM) hybrid sigma-pressure

interp_vintp2p_ecmwf(→ xarray.DataArray)

Interpolates data at multidimensional pressure levels to constant pressure coordinates and uses an ECMWF formulation to extrapolate values below ground.

Module Contents

easyclimate.interp.vinth2p.interp_vinth2p_dp(data_input: xarray.DataArray, surface_pressure_data: xarray.DataArray, surface_pressure_data_units: Literal['hPa', 'Pa', 'mbar'], hybrid_A_coefficients: xarray.DataArray, hybrid_B_coefficients: xarray.DataArray, vertical_output_level: list[int | float], vertical_input_dim: str, vertical_output_dim: str, vertical_output_dim_units: str, interp_method: Literal['linear', 'log', 'loglog'] = 'linear', extrapolation: bool = False, lon_dim: str = 'lon', lat_dim: str = 'lat', time_dim: str = 'time', p0_hPa=1000.0) → xarray.DataArray

Interpolate atmospheric data from Community Atmosphere Model (CAM) hybrid sigma-pressure coordinates to pressure levels.

This function performs vertical interpolation of atmospheric data (typically temperature) from hybrid sigma-pressure coordinates to specified pressure levels using the NCL’s vinth2p algorithm implemented in Fortran.

Parameters

data_inputxarray.DataArray.

Input 3D temperature field on hybrid levels with dimensions, e.g., (time, lev, lat, lon).

surface_pressure_dataxarray.DataArray.

Surface pressure field with dimensions, e.g., (time, lat, lon).

surface_pressure_data_unitsLiteral[“hPa”, “Pa”, “mbar”]

Units of the surface pressure data.

hybrid_A_coefficientsxarray.DataArray.

Hybrid A coefficients (pressure term) for the model levels.

hybrid_B_coefficientsxarray.DataArray.

Hybrid B coefficients (sigma term) for the model levels.

vertical_output_levellist[int]

List of target pressure levels for interpolation.

vertical_input_dimstr.

Name of the vertical dimension in the input data.

vertical_output_dimstr.

Name to use for the vertical dimension in the output data.

vertical_output_dim_unitsstr.

Units for the output pressure levels (must be convertible to hPa).

interp_methodLiteral[“linear”, “log”, “loglog”], optional

Interpolation method:

  • "linear": Linear interpolation

  • "log": Logarithmic interpolation

  • "loglog": Log-log interpolation

Default is "linear".

extrapolationbool., optional

Whether to extrapolate below the lowest model level when needed. Default is False.

lon_dimstr., optional

Name of the longitude dimension. Default is "lon".

lat_dimstr., optional

Name of the latitude dimension. Default is "lat".

time_dim: str, default: time.

The time coordinate dimension name. Default is "time".

p0_hPafloat., optional

Reference pressure in hPa for hybrid level calculation. Default is 1000.0 hPa.

Returns

xarray.DataArray

Interpolated data on pressure levels with dimensions, e.g., (time, plev, lat, lon), where plev corresponds to vertical_output_level.

See also

Examples

>>> # Interpolate temperature to pressure levels
>>> interp_vinth2p_dp(
...     data_input=temp_data,
...     surface_pressure_data=psfc_data,
...     surface_pressure_data_units="Pa",
...     hybrid_A_coefficients=hyam,
...     hybrid_B_coefficients=hybm,
...     vertical_output_level=[1000, 850, 700, 500, 300],
...     vertical_input_dim="lev",
...     vertical_output_dim="plev",
...     vertical_output_dim_units="hPa",
...     interp_method="log"
... )
easyclimate.interp.vinth2p.interp_vinth2p_ecmwf(data_input: xarray.DataArray, surface_pressure_data: xarray.DataArray, surface_pressure_data_units: Literal['hPa', 'Pa', 'mbar'], hybrid_A_coefficients: xarray.DataArray, hybrid_B_coefficients: xarray.DataArray, vertical_output_level: list[int | float], vertical_input_dim: str, vertical_output_dim: str, vertical_output_dim_units: str, variable_flag: Literal['T', 'Z', 'other'], temperature_bottom_data: xarray.DataArray | None = None, surface_geopotential_data: xarray.DataArray | None = None, interp_method: Literal['linear', 'log', 'loglog'] = 'linear', extrapolation: bool = True, lon_dim: str = 'lon', lat_dim: str = 'lat', time_dim: str = 'time', p0_hPa: float = 1000.0) → xarray.DataArray

Interpolate atmospheric data from Community Atmosphere Model (CAM) hybrid sigma-pressure coordinates to pressure levels using ECMWF extrapolation methods.

This function performs vertical interpolation of atmospheric data from hybrid sigma-pressure coordinates to specified pressure levels using the NCL’s vinth2p_ecmwf algorithm implemented in Fortran. It supports ECMWF-specific extrapolation for temperature (‘T’) and geopotential height (‘Z’) below the lowest hybrid level.

Parameters

data_inputxarray.DataArray

Input 3D field (e.g., temperature or geopotential) on hybrid levels with dimensions, e.g., (time, lev, lat, lon).

surface_pressure_dataxarray.DataArray

Surface pressure field with dimensions, e.g., (time, lat, lon).

surface_pressure_data_unitsLiteral["hPa", "Pa", "mbar"]

Units of the surface pressure data.

hybrid_A_coefficientsxarray.DataArray

Hybrid A coefficients (pressure term) for the model levels.

hybrid_B_coefficientsxarray.DataArray

Hybrid B coefficients (sigma term) for the model levels.

vertical_output_levellist[int | float]

List of target pressure levels for interpolation (in specified units).

vertical_input_dimstr

Name of the vertical dimension in the input data.

vertical_output_dimstr

Name to use for the vertical dimension in the output data.

vertical_output_dim_unitsstr

Units for the output pressure levels (must be convertible to hPa).

variable_flagLiteral["T", "Z", "other"]

Indicates the type of variable being interpolated: - “T”: Temperature (uses ECMWF extrapolation if enabled) - “Z”: Geopotential height (uses ECMWF extrapolation if enabled) - “other”: Any other variable (uses lowest level value for extrapolation)

temperature_bottom_dataOptional[xarray.DataArray], optional

Temperature at the lowest model level (required for ‘Z’ extrapolation). Dimensions, e.g., (time, lat, lon). Default is None.

surface_geopotential_dataOptional[xarray.DataArray], optional

Surface geopotential (required for ‘T’ or ‘Z’ extrapolation). Dimensions, e.g., (time, lat, lon). Default is None.

interp_methodLiteral["linear", "log", "loglog"], optional

Interpolation method:

  • "linear": Linear interpolation

  • "log": Logarithmic interpolation

  • "loglog": Log-log interpolation

Default is "linear".

extrapolationbool, optional

Whether to extrapolate below the lowest model level when needed. Default is False.

lon_dimstr, optional

Name of the longitude dimension. Default is “lon”.

lat_dimstr, optional

Name of the latitude dimension. Default is “lat”.

time_dim: str, default: time.

The time coordinate dimension name. Default is “time”.

p0_hPafloat, optional

Reference pressure in hPa for hybrid level calculation. Default is 1000.0 hPa.

Returns

xarray.DataArray

Interpolated data on pressure levels with dimensions, e.g., (time, plev, lat, lon), where plev corresponds to vertical_output_level.

Notes

  • The hybrid level pressure is calculated as: \(P = A \cdot p_0 + B \cdot \mathrm{psfc}\)

  • Output pressure levels are converted to hPa internally for calculations.

  • Missing values are converted to NaN in the output.

  • ECMWF extrapolation is applied only when extrapolation=True and variable_flag is ‘T’ or ‘Z’.

  • For ‘T’ or ‘Z’, tbot and phis must be provided when extrapolation=True.

See also

Examples

>>> # Interpolate temperature to pressure levels with ECMWF extrapolation
>>> interp_vinth2p_ecmwf(
...     data_input=temp_data,
...     surface_pressure_data=psfc_data,
...     surface_pressure_data_units="Pa",
...     hybrid_A_coefficients=hyam,
...     hybrid_B_coefficients=hybm,
...     vertical_output_level=[1000, 850, 700, 500, 300],
...     vertical_input_dim="lev",
...     vertical_output_dim="plev",
...     vertical_output_dim_units="hPa",
...     variable_flag="T",
...     temperature_bottom_data=tbot_data,
...     surface_geopotential_data=phis_data,
...     interp_method="log",
...     extrapolation=True
... )
easyclimate.interp.vinth2p.interp_vintp2p_ecmwf(data_input: xarray.DataArray, pressure_data: xarray.DataArray, pressure_data_units: Literal['hPa', 'Pa', 'mbar'], surface_pressure_data: xarray.DataArray, surface_pressure_data_units: Literal['hPa', 'Pa', 'mbar'], vertical_output_level: list[int | float], vertical_input_dim: str, vertical_output_dim: str, vertical_output_dim_units: str, variable_flag: Literal['T', 'Z', 'other'], temperature_bottom_data: xarray.DataArray | None = None, surface_geopotential_data: xarray.DataArray | None = None, interp_method: Literal['linear', 'log', 'loglog'] = 'linear', extrapolation: bool = False, lon_dim: str = 'lon', lat_dim: str = 'lat', time_dim: str = 'time') → xarray.DataArray

Interpolates data at multidimensional pressure levels to constant pressure coordinates and uses an ECMWF formulation to extrapolate values below ground.

This function performs vertical interpolation of atmospheric data from input pressure levels to specified output pressure levels using the NCL’s vintp2p_ecmwf algorithm implemented in Fortran. It supports ECMWF-specific extrapolation for temperature (‘T’) and geopotential height (‘Z’) below the lowest pressure level.

Parameters

data_inputxarray.DataArray

Input 3D field (e.g., temperature or geopotential) on pressure levels with dimensions, e.g., (time, lev, lat, lon).

pressure_dataxarray.DataArray

3D pressure field corresponding to the input data levels, with dimensions, e.g., (time, lev, lat, lon).

pressure_data_unitsLiteral[“hPa”, “Pa”, “mbar”]

Units of the pressure data.

surface_pressure_dataxarray.DataArray

Surface pressure field with dimensions, e.g., (time, lat, lon).

surface_pressure_data_unitsLiteral[“hPa”, “Pa”, “mbar”]

Units of the surface pressure data.

vertical_output_levellist[int | float]

List of target pressure levels for interpolation (in specified units).

vertical_input_dimstr

Name of the vertical dimension in the input data.

vertical_output_dimstr

Name to use for the vertical dimension in the output data.

vertical_output_dim_unitsstr

Units for the output pressure levels (must be convertible to hPa).

variable_flagLiteral["T", "Z", "other"]

Indicates the type of variable being interpolated: - “T”: Temperature (uses ECMWF extrapolation if enabled) - “Z”: Geopotential height (uses ECMWF extrapolation if enabled) - “other”: Any other variable (uses lowest level value for extrapolation)

temperature_bottom_dataOptional[xarray.DataArray], optional

Temperature at the lowest model level (required for ‘Z’ extrapolation). Dimensions, e.g., (time, lat, lon). Default is None.

surface_geopotential_dataOptional[xarray.DataArray], optional

Surface geopotential (required for ‘T’ or ‘Z’ extrapolation). Dimensions, e.g., (time, lat, lon). Default is None.

interp_methodLiteral["linear", "log", "loglog"], optional

Interpolation method:

  • “linear”: Linear interpolation

  • “log”: Logarithmic interpolation

  • “loglog”: Log-log interpolation

Default is “linear”.

extrapolationbool, optional

Whether to extrapolate below the lowest pressure level when needed. Default is False.

lon_dimstr, optional

Name of the longitude dimension. Default is “lon”.

lat_dimstr, optional

Name of the latitude dimension. Default is “lat”.

time_dim: str, default: time.

The time coordinate dimension name. Default is “time”.

Returns

xarray.DataArray

Interpolated data on pressure levels with dimensions, e.g., (time, plev, lat, lon), where plev corresponds to vertical_output_level.

Notes

  • The input pressure levels are provided directly via pressure_data.

  • Output pressure levels and surface pressure are converted to hPa internally for calculations.

  • Missing values are converted to NaN in the output.

  • ECMWF extrapolation is applied only when extrapolation=True and variable_flag is ‘T’ or ‘Z’.

  • For ‘T’ or ‘Z’, temperature_bottom_data and surface_geopotential_data must be provided when extrapolation=True.

See also

Examples

>>> # Interpolate temperature to pressure levels with ECMWF extrapolation
>>> interp_vintp2p_ecmwf(
...     data=temp_data,
...     pressure_data=pres_data,
...     pressure_data_units="Pa",
...     surface_pressure_data=psfc_data,
...     surface_pressure_data_units="Pa",
...     vertical_output_level=[1000, 850, 700, 500, 300],
...     vertical_input_dim="lev",
...     vertical_output_dim="plev",
...     vertical_output_dim_units="hPa",
...     variable_flag="T",
...     temperature_bottom_data=tbot_data,
...     surface_geopotential_data=phis_data,
...     interp_method="log",
...     extrapolation=True
... )