Environmental data format

Environmental data can be downloaded as a multilayer raster GeoTIFF (.tif) file. Projection is WGS 84 / UTM zone 38 (epsg: 32738) and resolution is 1km on an extent covering Madagascar. Data type is INT16 (16-bit integer value) with -32768 set as no value. The raster has 9 layers (named from environ.1 to environ.9) and an approximate size of 5 Mo. Layers describe the following environmental variables:

LayerEnvironmental variable
1Altitude (m)
2Slope (in degree)
3Aspect (clockwise from North, in degree)
4Solar radiation (Wh.m-2.day-1)
5Geology (Kew Botanical Garden, 1997)
6Soil (Pelletier, 1981)
7Vegetation (Kew Botanical Garden, 2007)
8Watersheds (Pearson, 2009)
9Percentage of forest cover for the year 2010 (%).

The raster file can be easily imported into any GIS software. If you use R and the raster package, you can import the raster and rename the 9 layers with the following piece of code:

library(raster)
s <- stack("environ.tif")
names(s) <- c("alt","slop","asp","solar","geol","soil","veg","wshed","percfor2010")

Then you can plot the altitude for Madagascar for example:

par(mar=c(3,3,1,1))
plot(s$alt,col=terrain.colors(255))
Altitude.

Altitude (m).