Real World Map request

[Saring]

I am writing a novel based on earth, though not the time or place we live in now. I'm looking for maps that show what the earth might look like in different situations, such as if the water level rose 20 feet world wide, how would that effect livable space? How would the world be different? I am also interested in focusing mostly in Europe and Asia, rather than north America. I was wondering if there is a program that anyone knows of that would allow me to play with earth to create what I'm looking for. Say an adjustable world map or something like that.

If there is nothing available, would anyone know of a way to do something like this simply? I'm not looking for specific detail right now, I just need to get some basic mapping ideas before I move forward with this.

[Diamond]

Try this: Flood Maps

[waldronate]

There is a lot of software out there that will do this sort of thing. I'm partial to Wilbur (available from software if you'd like to try it). Load a real-world data file and adjust the sea level, and there you are. Sure, there are things like Global Sea Level Rise Map - Global Warming & Climate Change Impact out there, but that hardly counts towards my mandated level of self-aggrandizement, now does it?