##
Comparing Maps 1

In the same way several other 1km world maps can be shown
:

- shadow maps, derived from the elevation model
- population maps, derived from satellite imagery
- several global landcover classifications

The shadow maps have been derived from the original elevation map by GRASS programs "sh.shade.rel". They show elevation with light coming from 45
135
, 225
and 315 degrees
, and a very pretty one from the river Rhine
.
The Landcover maps show three global landcover classification models, picked from the USGS Global Land Cover Characterization site, respectively the International Geosphere Biosphere Program (igbp)
, the Biosphere Atmosphere Transfer Scheme (Bats)
and the Global Ecosystems classification
in random colors (I couldn't find the color scheme for that one). I hadn't time to combine the landcover maps with the shadow elevation maps, but that would be very easy with the overlaying and transparency functions of MapServer.
Then there is the "stable lights" satellite composite from the Defense Meteorological Defense Program DMSP. This is based on observations from low-light imaging sensors in 1994/5, from which several types of stable light sources can be detected. The one shown here is the percentage of cities detected within each raster cell. On a global scale the picture is quite black
, but zooming in, e.g. to the US East Coast
or Rio the Janeiro
, shows an amazing amount of detail.