On Tue, Sep 6, 2016 at 10:36 AM, Helmut Kudrnovsky <[email protected]> wrote: > Hi Vero, > > > Veronica Andreo wrote >> Hi Helmut, >> >> I saw the announcement for this data set some time ago. I'm downloading >> now, just to give it a look. But, AFAIU, they are climatologies the same >> as >> worldclim. The remark is that they cover a more recent period than >> worldclim (1973-2013 compared to 1950-2000). But I know nothing about the >> quality of this data. Also worldclim developed a newer dataset that is >> still in beta (http://worldclim.org/version2)... Maybe worth comparison :) >> >> In any case, if they are just climatologies (averages over the years), I >> do >> not see much that you could do with tgrass that you couldn't do with the >> other modules (and I'm fan of tgrass!). You could however obtain the >> bio-climatic variables yourself with Markus Metz's add-on r.bioclim ( >> https://grass.osgeo.org/grass70/manuals/addons/r.bioclim.html) that works >> pretty nice. >> >> Cheers, >> Vero >> >> >> 2016-09-05 20:34 GMT+02:00 Helmut Kudrnovsky < > >> hellik@ > >> >: >> >>> hi community, >>> >>> there is an interesting new climate data set called >>> >>> CHELSA – Climatologies at high resolution for the earth’s land surface >>> areas >>> [1] >>> >>> CHELSA is a high resolution (30 arc sec) climate data set for the earth >>> land >>> surface areas >>> >>> has anyone already tried to use it within GRASS and maybe with the >>> temporal >>> GRASS suite? >>> >>> [1] http://chelsa-climate.org/ >>> >>> >>> >>> ----- >>> best regards >>> Helmut >>> -- >>> View this message in context: http://osgeo-org.1560.x6. >>> nabble.com/CHELSA-climate-data-set-tp5284115.html > > Thanks for the feedback. > > I've there is some raster extent issue with this data; already reported to > the data provider.
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. It seems it is easier to stick to worldclim... Markus M _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
