Use of cartopy instead of basemap

https://scitools.org.uk/cartopy/docs/latest/

Basemap is not longer under active development (see here). Future compatibility with other libraries such as matplotlib or numpy is unsure.

Currently, Basemap 1.3 is not compatible with matplotlib>=3.3 due to a deprecated function: https://github.com/matplotlib/basemap/issues/495

Apart from that, cartopy might enhance some figures in arosics.