easyclimate.core.rvdv

Divergence and Vorticity

Functions

calc_divergence_rs(→ xarray.DataArray)

Calculate the horizontal divergence term using the Rust backend.

calc_vorticity_rs(→ xarray.DataArray)

Calculate the horizontal relative vorticity term using the Rust backend.

calc_divergence_ncl(→ xarray.DataArray)

Calculate the horizontal divergence term using the NCL-compatible backend.

calc_vorticity_ncl(→ xarray.DataArray)

Calculate the horizontal relative vorticity term using the NCL-compatible backend.

calc_divergence(→ xarray.DataArray)

Calculate the horizontal divergence term.

calc_vorticity(→ xarray.DataArray)

Calculate the horizontal relative vorticity term.

Module Contents

easyclimate.core.rvdv.calc_divergence_rs(u_data: xarray.DataArray, v_data: xarray.DataArray, lon_dim: str = 'lon', lat_dim: str = 'lat', R: float = 6371220.0, cyclic_boundary_setting: Literal['nan', 'cyclic', 'cyclic+diff', 'diff'] = 'nan', method: Literal['rust-batch', 'rust-raw'] = 'rust-batch') → xarray.DataArray

Calculate the horizontal divergence term using the Rust backend.

This function wraps the Rust finite-difference implementation for spherical wind fields and supports both batched and raw execution modes.

Parameters

u_data: xarray.DataArray.

The zonal wind data.

v_data: xarray.DataArray.

The meridional wind data.

lon_dim: str, default: lon.

Longitude coordinate dimension name.

lat_dim: str, default: lat.

Latitude coordinate dimension name.

R: float, default: 6371220.0.

Radius of the Earth in meters.

cyclic_boundary_setting: {“nan”, “cyclic”, “cyclic+diff”, “diff”}, default: nan.

A scalar integer equal to the boundary condition option:

  • nan: Boundary points are set to the missing value.

  • cyclic: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic point.) The upper and lower boundaries will be set to missing.

  • cyclic+diff: Boundary points are estimated using one-sided difference schemes normal to the boundary.

  • diff: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic points.) The upper and lower boundaries are estimated using a one-sided difference scheme normal to the boundary.

method: {“rust-batch”, “rust-raw”}, default: “rust-batch”.

Rust execution mode. rust-batch uses the batched backend function, while rust-raw loops over non-core dimensions and calls the raw backend.

Returns

The horizontal divergence term. (xarray.DataArray).

easyclimate.core.rvdv.calc_vorticity_rs(u_data: xarray.DataArray, v_data: xarray.DataArray, lon_dim: str = 'lon', lat_dim: str = 'lat', R: float = 6371220.0, cyclic_boundary_setting: Literal['nan', 'cyclic', 'cyclic+diff', 'diff'] = 'nan', method: Literal['rust-batch', 'rust-raw'] = 'rust-batch') → xarray.DataArray

Calculate the horizontal relative vorticity term using the Rust backend.

This function wraps the Rust finite-difference implementation for spherical wind fields and supports both batched and raw execution modes.

Parameters

u_data: xarray.DataArray.

The zonal wind data.

v_data: xarray.DataArray.

The meridional wind data.

lon_dim: str, default: lon.

Longitude coordinate dimension name.

lat_dim: str, default: lat.

Latitude coordinate dimension name.

R: float, default: 6371220.0.

Radius of the Earth in meters.

cyclic_boundary_setting: {“nan”, “cyclic”, “cyclic+diff”, “diff”}, default: nan.

A scalar integer equal to the boundary condition option:

  • nan: Boundary points are set to the missing value.

  • cyclic: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic point.) The upper and lower boundaries will be set to missing.

  • cyclic+diff: Boundary points are estimated using one-sided difference schemes normal to the boundary.

  • diff: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic points.) The upper and lower boundaries are estimated using a one-sided difference scheme normal to the boundary.

method: {“rust-batch”, “rust-raw”}, default: rust-batch.

Rust execution mode. rust-batch uses the batched backend function, while rust-raw loops over non-core dimensions and calls the raw backend.

Returns

The horizontal relative vorticity term. (xarray.DataArray).

easyclimate.core.rvdv.calc_divergence_ncl(u_data: xarray.DataArray, v_data: xarray.DataArray, lon_dim: str = 'lon', lat_dim: str = 'lat', cyclic_boundary_setting: Literal['nan', 'cyclic', 'cyclic+diff', 'diff'] = 'nan') → xarray.DataArray

Calculate the horizontal divergence term using the NCL-compatible backend.

This function wraps the NCL-style finite-difference implementation and keeps the input dimension order unchanged in the returned result.

Note

The R values in the NCL-compatible backend are fixed to 6371220.0 meters, which is the radius of the Earth. The NCL-style implementation assumes a spherical Earth and does not allow for a user-specified radius.

Parameters

u_data: xarray.DataArray.

The zonal wind data.

v_data: xarray.DataArray.

The meridional wind data.

lon_dim: str, default: lon.

Longitude coordinate dimension name.

lat_dim: str, default: lat.

Latitude coordinate dimension name.

cyclic_boundary_setting: {“nan”, “cyclic”, “cyclic+diff”, “diff”}, default: nan.

A scalar integer equal to the boundary condition option:

  • nan: Boundary points are set to the missing value.

  • cyclic: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic point.) The upper and lower boundaries will be set to missing.

  • cyclic+diff: Boundary points are estimated using one-sided difference schemes normal to the boundary.

  • diff: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic points.) The upper and lower boundaries are estimated using a one-sided difference scheme normal to the boundary.

Returns

The horizontal divergence term. (xarray.DataArray).

easyclimate.core.rvdv.calc_vorticity_ncl(u_data: xarray.DataArray, v_data: xarray.DataArray, lon_dim: str = 'lon', lat_dim: str = 'lat', cyclic_boundary_setting: Literal['nan', 'cyclic', 'cyclic+diff', 'diff'] = 'nan') → xarray.DataArray

Calculate the horizontal relative vorticity term using the NCL-compatible backend.

This function wraps the NCL-style finite-difference implementation and keeps the input dimension order unchanged in the returned result.

Note

The R values in the NCL-compatible backend are fixed to 6371220.0 meters, which is the radius of the Earth. The NCL-style implementation assumes a spherical Earth and does not allow for a user-specified radius.

Parameters

u_data: xarray.DataArray.

The zonal wind data.

v_data: xarray.DataArray.

The meridional wind data.

lon_dim: str, default: lon.

Longitude coordinate dimension name.

lat_dim: str, default: lat.

Latitude coordinate dimension name.

cyclic_boundary_setting: {“nan”, “cyclic”, “cyclic+diff”, “diff”}, default: nan.

A scalar integer equal to the boundary condition option:

  • nan: Boundary points are set to the missing value.

  • cyclic: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic point.) The upper and lower boundaries will be set to missing.

  • cyclic+diff: Boundary points are estimated using one-sided difference schemes normal to the boundary.

  • diff: The u and v arrays are cyclic in longitude. (The arrays should NOT include the cyclic points.) The upper and lower boundaries are estimated using a one-sided difference scheme normal to the boundary.

Returns

The horizontal relative vorticity term. (xarray.DataArray).

easyclimate.core.rvdv.calc_divergence(u_data: xarray.DataArray, v_data: xarray.DataArray, lon_dim: str = 'lon', lat_dim: str = 'lat', R: float = 6371220.0, spherical_coord: bool = True, cyclic_boundary_setting: Literal['nan', 'cyclic', 'cyclic+diff', 'diff'] = 'diff') → xarray.DataArray

Calculate the horizontal divergence term.

rectangular coordinates

\[\mathrm{D} = \frac{\partial u}{\partial x} + \frac{\partial v}{\partial y}\]

Spherical coordinates

\[\mathrm{D} = \frac{\partial u}{\partial x} + \frac{\partial v}{\partial y} - \frac{v}{R} \tan \varphi\]

Parameters

u_data: xarray.DataArray.

The zonal wind data.

v_data: xarray.DataArray.

The meridional wind data.

lon_dim: str, default: lon.

Longitude coordinate dimension name. By default extracting is applied over the lon dimension.

lat_dim: str, default: lat.

Latitude coordinate dimension name. By default extracting is applied over the lat dimension.

R: float, default: 6.37122e6.

Radius of the Earth.

spherical_coord: bool, default: True.

Whether or not to compute the horizontal Laplace term in spherical coordinates.

cyclic_boundary_setting: {“nan”, “cyclic”, “cyclic+diff”, “diff”}, default: diff.

Boundary behavior matching calc_divergence_rs(). The default keeps finite values at all boundaries, matching the historical raw function behavior most closely.

Returns

The horizontal divergence term. (xarray.DataArray).

See also

easyclimate.core.rvdv.calc_vorticity(u_data: xarray.DataArray, v_data: xarray.DataArray, lon_dim: str = 'lon', lat_dim: str = 'lat', R: float = 6371220.0, spherical_coord: bool = True, cyclic_boundary_setting: Literal['nan', 'cyclic', 'cyclic+diff', 'diff'] = 'diff') → xarray.DataArray

Calculate the horizontal relative vorticity term.

rectangular coordinates

\[\zeta = \frac{\partial v}{\partial x} - \frac{\partial u}{\partial y}\]

Spherical coordinates

\[\zeta = \frac{\partial v}{\partial x} - \frac{\partial u}{\partial y} + \frac{u}{R} \tan \varphi\]

Parameters

u_data: xarray.DataArray.

The zonal wind data.

v_data: xarray.DataArray.

The meridional wind data.

lon_dim: str, default: lon.

Longitude coordinate dimension name. By default extracting is applied over the lon dimension.

lat_dim: str, default: lat.

Latitude coordinate dimension name. By default extracting is applied over the lat dimension.

R: float, default: 6370000.

Radius of the Earth.

spherical_coord: bool, default: True.

Whether or not to compute the horizontal Laplace term in spherical coordinates.

cyclic_boundary_setting: {“nan”, “cyclic”, “cyclic+diff”, “diff”}, default: diff.

Boundary behavior matching calc_vorticity_rs(). The default keeps finite values at all boundaries, matching the historical raw function behavior most closely.

Returns

The horizontal relative vorticity term. (xarray.DataArray).

See also