"""
==================================
Multiple plots and map projections
==================================

Control the map projection parameters on multiple axes

This example illustrates how to plot multiple maps and control their extent
and aspect ratio.

For more details see `this discussion`_ on github.

.. _this discussion: https://github.com/pydata/xarray/issues/1397#issuecomment-299190567
"""


import cartopy.crs as ccrs
import matplotlib.pyplot as plt

import xarray as xr

# Load the data
ds = xr.tutorial.load_dataset("air_temperature")
air = ds.air.isel(time=[0, 724]) - 273.15

# This is the map projection we want to plot *onto*
map_proj = ccrs.LambertConformal(central_longitude=-95, central_latitude=45)

p = air.plot(
    transform=ccrs.PlateCarree(),  # the data's projection
    col="time",
    col_wrap=1,  # multiplot settings
    aspect=ds.dims["lon"] / ds.dims["lat"],  # for a sensible figsize
    subplot_kws={"projection": map_proj},  # the plot's projection
)

# We have to set the map's options on all four axes
for ax in p.axes.flat:
    ax.coastlines()
    ax.set_extent([-160, -30, 5, 75])
    # Without this aspect attributes the maps will look chaotic and the
    # "extent" attribute above will be ignored
    ax.set_aspect("equal")

plt.show()