Add Potential Virtual Ship case studies notebook

[ammedd]

The latest tutorial refers to a document https://surfdrive.surf.nl/files/index.php/s/U1dQKsjg9MkFNvm with case studies. Let's create a notebook instead!

Containing:
A map of the world with e.g. average surface currents
An easy way to add points to the map with labels
A numbered/labelled list of potential research areas, i.e. the one in the doc and e.g. the Agulhas Leakage (rings), the Bay of Bengal (Monsoons and freshwater stratification), Brazil-Malvinas (pretty busy place with two currents encountering each other and a lot of eddies).

[ammedd]

Here's the doc version for easy copying https://surfdrive.surf.nl/files/index.php/s/NoOaPS2KIVi1OwV