Three Map Sets? Nearly all Raven maps are built on a landforms base, using a combination of shading and elevation tints. That presents a clear and meaningful picture, but doesn't leave much graphic room for showing other interesting information. That would take additional versions - covering the same area with a different treatment to illustrate different characteristics. We've been working on those for years, and now have them for all the Regional maps. The variations are best explained by example. Elevation Tints (below) The West is above all a land of mountains and high plateaus. It is marked by a generally abrupt eastern border, the Rocky Mountain front, broken by only a few outliers, most notable the Black Hills. Interior plateaus are typically fairly high, with the exception of the Columbia Basin. Interior lowlands follow an obvious arc interrupted by discrete mountain blocks. Land Cover (Below) The over-all pattern is of forested lands in the north and at higher elevations up to marked timberlines on the highest mountains and ridges. Barren lands increase to the south, forests retreat up slope, and farmlands, very extensive from Edmonton to Lubbock on the neighboring Plains, are mostly in isolated pockets. Those overall patterns are attributable to storm tracks off the Pacific at higher latitude, and the rain-shadow effect of north-south ridges, particularly the Coast Ranges, the Cascades, and the Sierra Nevada. Landforms (Below) The extreme landform detail apparent on this map shows up patterns which are barely visible on the Elevation and Land Cover versions. The Fraser Plateau, the Columbia Basin, and Lake River Plains stand out in very sharp contrast to the neighboring mountains. The Rocky Mountain Trench's unbroken trace from (at least) Flathead Lake to Alaska; the Green River's canyons on both side of the San Gabriel and San Bernardino mountain wall east of Los Angeles are a handful. All of these features can be found on the Elevaion and Landform versions, but they are most spectacularly present on this map.
