shoot.dyn.get_geos

shoot.dyn.get_geos(ssh, dx=None, dy=None)

Compute geostrophic currents from SSH

Uses geostrophic balance: f×u_g = -g∇η

Parameters:

• ssh (xarray.DataArray) – Sea surface height in meters.

• dx (xarray.DataArray, optional) – Grid resolution along X in meters.

• dy (xarray.DataArray, optional) – Grid resolution along Y in meters.

Returns:

• u (xarray.DataArray) – Zonal geostrophic velocity in m/s.

• v (xarray.DataArray) – Meridional geostrophic velocity in m/s.

Example

>>> import xarray as xr, numpy as np
>>> from shoot.dyn import get_geos
>>> lon = xr.DataArray(np.linspace(0, 2, 50), dims="lon",
...     attrs={"standard_name": "longitude"})
>>> lat = xr.DataArray(np.linspace(43, 44, 40), dims="lat",
...     attrs={"standard_name": "latitude"})
>>> ssh = xr.DataArray(np.random.rand(40, 50) * 0.1, dims=("lat", "lon"),
...     coords={"lon": lon, "lat": lat})
>>> u, v = get_geos(ssh)