As seas rise, waves coming ashore will intensify, worsening already eroding hot spots.

Problems will come as much from the estuaries as the ocean, with seas rising over the wildlife nursery marshes. As just one example of the environmental consequences, juvenile shrimp that feed in the marshes will be lost.

Then there are the triggers — storms or other sudden events that do major damage to a developed coast.

They range from passing storms, such as Hurricane Irene, to a possible collapse of the West Antarctica Ice Shelf.

Irene in 2011 wiped out the dunes at Folly Beach County Park, and in two short years turned it from a maritime forest beach needing periodic sand renourishment to a nearly barren overwash beach in desperate need of sand to survive.

The change is occurring so quickly that professor Scott Harris’ College of Charleston environmental geo-sciences students are documenting the phenomenon as “a fantastic science experiment,” he said.

The West Antarctica Ice Shelf is a fracturing, 10 million-mile expanse that, if plopped into the ocean, would cause sea levels to rise some 10 feet within a few years, “like putting an ice cube in a full glass of tea,” Harris said.

If that happens, “we’re going to change our understanding greatly of how we need to behave as a coastal zone. It will be economically destructive.”