> According to gdalinfo, the pixel sizes are > Pixel Size = (0.008333333300000,-0.008333333300000) > should be > Pixel Size = (0.008333333333333,-0.008333333333333) > i.e. fp precision is too low which explains why west is not exactly on > -180 but -180.0001389, just as south is not exactly -90 but > -90.0001389. > > There are 43207 columns, but with 30 seconds there should be 43200 > columns meaning that there are 7 excess columns to the east. > Considering that the 7 westernmost columns and the 7 easternmost > columns overlap, their values should be identical. > > There are 21599 rows, but with 30 seconds covering -90, 90 there > should be 21600 rows. The northernmost row is missing and north should > be 89:59:30. The data would need to be prepared with gdal_translate, > cutting off the 7 excess columns to the east and fixing the extents, > before they can be imported into GRASS.
I had a conversation with the data provider. according to them, the climate rasters are based upon GMTED2010 [1] in the description of the GMTED2010 data [2] 30 arc-seconds GMTED2010 data: Resolution (decimal degrees) 0.0083333333 West extent: minimum X-coordinate (longitude) -180.0001388888 South extent: minimum (for mean): -90.0001388888 (for others: -56.0001388888) East extent: maximum X-coordinate (longitude) 179.9998611111 North extent: maximum Y-coordinate (latitude) 83.9998611111 Rows (for mean): 20,880 (for others: 16,800) Columns: 43,200 it seems the original GMTED2010 data has an intentional half-pixel-shift. any idea? [1] http://erouault.blogspot.co.at/2011/12/seamless-access-to-remote-global-multi.html [2]https://pubs.usgs.gov/of/2011/1073/pdf/of2011-1073.pdf ----- best regards Helmut -- View this message in context: http://osgeo-org.1560.x6.nabble.com/CHELSA-climate-data-set-tp5284115p5284378.html Sent from the Grass - Users mailing list archive at Nabble.com. _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user