Demo using cartopy.util.add_cyclic_point with an xarray Dataset to add a cyclic or wrap-around pixel to the `lon` dimension. This can be useful for plotting with `cartopy` or regridding with `xesmf`.

xarray_wrap_around_pixel_demo.py

"""
Demo using cartopy.util.add_cyclic_point with an xarray Dataset to 
add a cyclic or wrap-around pixel to the `lon` dimension. This can be useful
for plotting with `cartopy` or regridding with `xesmf`.
"""

import xarray as xr
from cartopy.util import add_cyclic_point


def cyclic_wrapper(x, dim="lon"):
    """So add_cyclic_point() works on 'dim' via xarray Dataset.map()"""
    wrap_data, wrap_lon = add_cyclic_point(
        x.values, 
        coord=x.coords[dim].data,
        axis=x.dims.index(dim)
    )
    return xr.DataArray(
        wrap_data, 
        coords={dim: wrap_lon, **x.drop(dim).coords}, 
        dims=x.dims
    )


# Whatever data you want to plot or regrid. Needs "lon" dim.
raw = xr.open_dataset("somedata.nc")

# Add cyclic points.
ds = raw.map(cyclic_wrapper, keep_attrs=True)