Data: a world elevation map, elev, which was downloaded from Manuel Gimond's web site
The original crs is as follows:
I did a test as follows, just out of curiosity:
elev_projected <- projectRaster(elev, crs = "+proj=utm +ellpse=WGS84") # the +zone= parameter not specified
In ArcGIS Desktop, when projecting to UTM, we have to specify which specific zone to use. R, however, seems to allow this to happen w/o complaining. Even though there was a warning message, the raster was projected anyway.
3 projected point(s) not finite
The extent of the output is as follows:
I wonder what actually happens when the zone parameter is missing from the proj string. Does this string make any sense? The output map is attached. Thanks.