"I how about we give anyone who lives 3 miles off shore the freedom from some federal and state taxes? And have as a priority zoning laws that allows the infrastructure to be built that allows people living beyond 3 miles of shore to commute to the "mainland". And generally encourage by removing various laws prevent people living on and in the ocean.

In same way one could look at NASA working towards a time where people could living in space. We could have policies that allow people to live, and work in the ocean environment.

If we are building cities or communities that float or are underwater it doesn't make much difference if in a 100 years sea level rise whatever crazy amount you think is possible.
As for concern about rising CO2, we farm the ocean. In the open ocean there a lack of plant nutrients, therefore we could increase these levels and thereby increase quantity of sea life dependent upon this food source. If we could double or triple the amount plant life in the oceans we would probably have a CO2 shortage."

For rules see:
http://www.samizdata.net/blog/archives/2008/03/how_would_free.html
Entry by Dale Amon
Which can be boiled down to:
"The discussion I would like to see is about the answers we as libertarians have if climate change is indeed real."