Alternate history of North America

[Jerian]

If you want a better Base Map, try this: http://draconic.ca/~smithkm/northam.png

I slapped it together in QGIS using data from Natural Earth. It's a stereographic projection centred at N 45° W 100° (Go south from Lake Manitoba to the border between North and South Dakota)

That is a good one. It has some things I like, others I don't.

I'm not really too fond of the curvature, I generally like straightened maps (even if they are more stretched). The rivers are unnecessary, and would just clutter it up. I love the inclusion of state/province borders, it would make alignment significantly easier, however, I'd have to cut out quite a few of them.

It would take a lot of work to catch up on, but I think I could make a much better map with this stock image.

Thanks, I'll save it.

-Jerian

[Hai-Etlik]

That is a good one. It has some things I like, others I don't.

I'm not really too fond of the curvature, I generally like straightened maps (even if they are more stretched). The rivers are unnecessary, and would just clutter it up. I love the inclusion of state/province borders, it would make alignment significantly easier, however, I'd have to cut out quite a few of them.

It would take a lot of work to catch up on, but I think I could make a much better map with this stock image.

The "straightened" maps you are thinking of (All meridians and parallels are straight lines) are technically called "Normal Cylindrical". "Cylindrical" means you can think of the map as being wrapped around the Earth in a cylinder, "Normal" means the cylinder is wrapped around the axis of the Earth. The Mercator, Plate Carree, and Gall-Peters projections are all Normal Cylindrical projections. The problem with such projections is that they have infinite distortion at the poles and their distortion varies quite rapidly with latitude and the rate that the distortion occurs increases as you near the poles. This makes such projections really bad for maps that cover areas near the poles. In fact they are generally discouraged in modern mapping except where they are needed for their technical simplicity or for very specific properties like Mercator's 'zoomability' making it the common choice for web maps like Google Maps.

Really, the world is curved. The 49th parallel is a circle (And not a "great circle" which is the spherical equivalent of a straight line) So any projection suitable for a regional map of North America is going to show it as being curved. The meridians could be straightened out by using a conic projection (The map wraps around the Earth in a cone) rather than an azimuthal one as I've hone here (The map touches the Earth flat at a single point)

River data is probably something you should pay attention to in an alternate history, even if you don't include it in a final map. Rivers are one of the major features used for borders. The boundaries of watersheds are another. You might want to try playing with the data from Natural Earth directly. It requires specialized GIS software rather than graphics software but such software is available for free (Look up QuantumGIS). There's also watershed data available here: CEC - Atlas: Watersheds