pvtend.sh_ops.invert_laplacian_sh

pvtend.sh_ops.invert_laplacian_sh(rhs: ndarray, lat: ndarray, lon: ndarray, R_earth: float = 6371000.0, parity: str = 'scalar') → ndarray[source]

Solve ∇²χ = rhs on the sphere with the global-mean zero gauge.

Parameters:

  • rhs – Right-hand side, shape (nlat, nlon).

  • lat – Latitudes in degrees, ascending.

  • lon – Longitudes in degrees.

  • R_earth – Earth radius in metres.

  • parity – Mirror parity used when rhs is NH-only. Defaults to "scalar" (even). Set to "v" for a divergence-like RHS that is odd across the equator.

Returns:

χ of the same shape as rhs, with the global area-weighted mean removed (Fredholm-compatible gauge fix).