Wiki is a good place to start:
There are lots of genera in the family Cicadidae.
Magicicada is the genus of the 13 and 17 year periodical cicadas of the US.
Other cicada mostly have a life cycle of 2 to 5 years.
Last year’s Brood X magicicada did much damage to fruit trees, but that’s not to the exclusion of Elm, Linden etc. I don’t think I’ve ever seen any on pine. Here’s a list:
Here’s more information, with a brood emergence list, and brood maps. As you can see, there are no magicicada on the coast, but brood X extends to the shore.
Cicada usually come up over a period of weeks in July and August, but there are often some early ones too.
You may be hearing grasshoppers, rather than cicadas out on the dunes. Not living near the shore, most of the cicada I notice hang out in large trees.
The cicada faq offers this useful insight into the derivation of the name cicada: