If you've seen "An Inconvenient Truth," you'll remember the part where they show what famous coastal cities would look like if the ocean levels rose. It's a pretty impressive graphic, easily done with a bit of computer animation and a topographic map.
My town sits mostly at sea level, so I starting wondering how much we would change if the oceans rose. Here is an overview of my town currently. The orange lines are the main roads, and the pink signifies where buildings are located.
Estimates of how much the ocean could rise range from 10 to 40 feet. My topo map only shows a base line of 30 or 40 feet (I'm not sure, since I can't seem to find a legend), so I had to assume a rise on the higher end of the estimate. Here is my town again after the 30-40ft rise, more or less.
Even with a 20 foot rise (the average estimate) we would lose half the town, the railway, and every major road. In fact, there might not be any way at all to escape town without a boat.
It's an interesting scenario, though a bit alarming. I should also add that very few people in town buy into the idea of global warming. Very alarming indeed.