I have a raster file (grd file) for Antarctica in polar stereographic (x,y) coordinates and I would like to import the file. There is any way to import it or do I need to convert this file in Longitude,Latitude format?
You can try to import it using
File > Import > Import Raster. GPlates supports inbuilt raster spatial reference systems (eg, Lambert Conformal Conic) and these should be stored in your