potential_vorticity_barotropic

metpy.calc.potential_vorticity_barotropic(height, u, v, dx=None, dy=None, latitude=None, x_dim=- 1, y_dim=- 2)[source]

Calculate the barotropic (Rossby) potential vorticity.

\[PV = \frac{f + \zeta}{H}\]

This formula is based on equation 7.27 [Hobbs2006].

Parameters

  • height ((…, M, N) xarray.DataArray or pint.Quantity) – atmospheric height

  • u ((…, M, N) xarray.DataArray or pint.Quantity) – x component of the wind

  • v ((…, M, N) xarray.DataArray or pint.Quantity) – y component of the wind

  • dx (pint.Quantity, optional) – The grid spacing(s) in the x-direction. If an array, there should be one item less than the size of u along the applicable axis. Optional if xarray.DataArray with latitude/longitude coordinates used as input.

  • dy (pint.Quantity, optional) – The grid spacing(s) in the y-direction. If an array, there should be one item less than the size of u along the applicable axis. Optional if xarray.DataArray with latitude/longitude coordinates used as input.

  • latitude (pint.Quantity, optional) – Latitude of the wind data. Optional if xarray.DataArray with latitude/longitude coordinates used as input. Note that an argument without units is treated as dimensionless, which translates to radians.

  • x_dim (int, optional) – Axis number of x dimension. Defaults to -1 (implying […, Y, X] order). Automatically parsed from input if using xarray.DataArray.

  • y_dim (int, optional) – Axis number of y dimension. Defaults to -2 (implying […, Y, X] order). Automatically parsed from input if using xarray.DataArray.

Returns

(…, M, N) xarray.DataArray or pint.Quantity – barotropic potential vorticity

Changed in version 1.0: Changed signature from (heights, u, v, dx, dy, lats, dim_order='yx')

potential_vorticity_baroclinic q_vector