We used Mathematica to "paint" 8-km elevation cells with a color scheme that represents water in blue and the continuum of NDVI values from brown to green. Vegetation is most intense on the western slopes of the two mountain ranges (indicated by the green band along the Sierras at the top of the picture), and the lowest values of vegetation in the study area are in the heavily urbanized San Francisco Bay area shown by the brown tint in the foreground.