Hi, Have you tried using the 'prj' argument to writeRaster? I don't know that it will be the solution, but according to ...
https://www.rdocumentation.org/packages/raster/versions/2.8-19/topics/writeRaster <https://www.rdocumentation.org/packages/raster/versions/2.8-19/topics/writeRaster> It is documented among the '...' arguments. Setting prj = TRUE will cause the crs to be written to the file. Cheers, Ben > On Feb 12, 2019, at 8:34 AM, Ahmed El-Gabbas <elgab...@gmail.com> wrote: > > Hello all, > > I am having a problem while converting a raster object as NetCDF (.nc) file, > with keeping the CRS information in the output file. > Here is a reproducible code: > require(raster) > require(ncdf4) > CurrTemp <- tempfile() > download.file(url = > "https://seaice.uni-bremen.de/data/amsre/asi_daygrid_swath/s6250/2003/feb/Antarctic/asi-s6250-20030214-v5.hdf > > <https://seaice.uni-bremen.de/data/amsre/asi_daygrid_swath/s6250/2003/feb/Antarctic/asi-s6250-20030214-v5.hdf>", > destfile = CurrTemp, mode = "wb", quiet = T) > r <- raster(CurrTemp) > r <- flip(r,2) > extent(r) <- c(-3950000, 3950000, -3950000, 4350000) > crs(r) <- "+proj=stere +lat_0=-90 +lat_ts=-70 +lon_0=0 +k=1 +x_0=0 +y_0=0 > +a=6378273 +b=6356889.449 +units=m +no_defs" > r > # class : RasterLayer > # dimensions : 1328, 1264, 1678592 (nrow, ncol, ncell) > # resolution : 6250, 6250 (x, y) > # extent : -3950000, 3950000, -3950000, 4350000 (xmin, xmax, ymin, ymax) > # coord. ref. : +proj=stere +lat_0=-90 +lat_ts=-70 +lon_0=0 +k=1 +x_0=0 > +y_0=0 +a=6378273 +b=6356889.449 +units=m +no_defs > # data source : in memory > # names : layer > # values : 0, 100 (min, max) > So far the raster object reads well, with CRS information included. > However, when I try to save it as .nc file, R prints "coord. ref. : NA", and > the produced file does not contain the CRS information. > writeRaster(r, filename = "O:/Ahmed/r001.nc <http://r001.nc/>", > varname="IceConc", > overwrite=TRUE, format="CDF", > xname="Longitude", yname="Latitude") > # class : RasterLayer > # dimensions : 1328, 1264, 1678592 (nrow, ncol, ncell) > # resolution : 6250, 6250 (x, y) > # extent : -3950000, 3950000, -3950000, 4350000 (xmin, xmax, ymin, ymax) > # coord. ref. : NA > # data source : O:/Ahmed/r001.nc <http://r001.nc/> > # names : IceConc > # zvar : IceConc > > raster("O:/Ahmed/r001.nc <http://r001.nc/>") > # class : RasterLayer > # dimensions : 1328, 1264, 1678592 (nrow, ncol, ncell) > # resolution : 6250, 6250 (x, y) > # extent : -3950000, 3950000, -3950000, 4350000 (xmin, xmax, ymin, ymax) > # coord. ref. : NA > # data source : O:/Ahmed/r001.nc <http://r001.nc/> > # names : IceConc > # zvar : IceConc > Any solution? > > N.B. I also sent the same question at stackoverflow > <https://stackoverflow.com/questions/54593552/saving-r-raster-to-netcdf-nc-file-with-keeping-crs-information>, > without a solution so far. > > Thanks > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > Dr. Ahmed El-Gabbas, > Ocean Acoustics Lab, > Alfred-Wegener-Institut > Helmholtz-Zentrum für Polar und Meeresforschung > <image.png> > My Website: https://elgabbas.github.io > <https://elgabbas.github.io/>_______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-geo Ben Tupper Bigelow Laboratory for Ocean Sciences 60 Bigelow Drive, P.O. Box 380 East Boothbay, Maine 04544 http://www.bigelow.org Ecological Forecasting: https://eco.bigelow.org/ [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
