Add cartopy to intersphinx

docs/conf.py

@@ -87,6 +87,7 @@ autodoc_typehints = "description"
 
 # sphinx.ext.intersphinx
 intersphinx_mapping = {
+    "cartopy": ("https://scitools.org.uk/cartopy/docs/latest/", None),
     "python": ("https://docs.python.org/3", None),
     "pytorch-lightning": ("https://pytorch-lightning.readthedocs.io/en/latest/", None),
     "rasterio": ("https://rasterio.readthedocs.io/en/latest/", None),