Elevation Lines
I made a number of improvements to the earlier Joy Division-inspired Elevation Visualization map that I posted. I increased the apparent vertical exaggeration, added a number of tweaks to deal with zoom level, and removed water areas for better interpretation. In addition, one can draw their own cross sections which are also vertically offset, just like the base lines.
Elevation Lines
To access elevation values on-the-fly, I pulled in another elevation-related experiment that I've been working on: the ability to access height values (in this case, from the Shuttle Radar Topography Mission - also the source of the Elevation lines) from raster map tiles. To the layperson, this may not seem like a big deal, but I think it is the most interesting (and complex) part. The elevation values themselves are encoded in the tiles, in a three position base-256 system (here is a funny little demo) that allows for over 16 million unique values. If you click "Toggle Elevation" you will see what it looks like. These image tiles - and the pixel-by-pixel height values that they contain - are then loaded and accessed using a Leaflet Tiled Canvas Layer.
There are many interesting patterns to be found, some from artifacts in the data, other from variations in Earth surface processes, particularly in how depositionally-dominated landforms (and their very low gradient slopes) appear:
The Central Valley:
The Pampas:
The Mississippi Delta and Floodplain:
