[jccooper]

Dialect can include pronunciation, vocabulary, word choice, grammar, semantics, and other ways of speaking where accent refers only to ways of pronunciation. Academics almost always go with "dialect" for "different ways of speaking" unless they're specifically meaning only pronunciation. And sometimes not even then.

The differences covered here do seem to be mostly accent (though some might consider sound changes to be more than accent), but calling it dialect allows for broader consideration if warranted.