[GRASS-user] CHELSA climate data set

[Veronica Andreo]

Hi Helli,

Yes, if you want the global map the -a flag plus the relaxed conditions for
the extent of global maps are fine...

However, I wanted to also only import the region i'm working on and make
use of the -r flag in r.in.gdal... then the problems start... no
combination of -a, raster or align parameters in r.region give me the
correct region (either the resolution is wrong or the extent). My solution
so far is import the global map with r.in.gdal -a, then use r.mapcalc to
get the region I need... any other suggestion about better workflow is more
than welcome :)

best,
Vero

2017-05-02 21:45 GMT+02:00 Helmut Kudrnovsky <hellik at web.de>:

> Veronica Andreo wrote
> > Hi :)
> >
> > JFYI, CHELSA v1.2 is out
> >
> > 2017-02-07 15:43 GMT+01:00 Markus Neteler <
>
> > neteler@
>
> > >:
> >
> >> On Tue, Feb 7, 2017 at 3:32 PM, Markus Metz
> >> <
>
> > markus.metz.giswork@
>
> > > wrote:
> >> [...]
> >> > Compared to GMTED, CHELSA extents further south to 90:0:0.5S which
> >> conforms
> >> > to the GMTED grid geometry. For CHELSA, however gdalinfo reports
> >> > Pixel Size = (0.008333333300000,-0.008333333300000)
> >> > while for GMTED, gdalinfo reports
> >> > Pixel Size = (0.008333333333333,-0.008333333333333)
> >> >
> >> > The reason for the slightly smaller pixel size is most probably
> reduced
> >> > floating point precision during creation of the CHELSA data.
> >>
> >> from personal comm.:
> >> They are currently investigating where the precision is cut in their
> >> workflow (the upcoming V1.2 shall come with a related correction).
> >>
> >
> > Unfortunately they have not corrected the precision issue...
> >
> > gdalinfo CHELSA_temp_2_1979-2013_V1.2_land.tif
> > Driver: GTiff/GeoTIFF
> > Files: CHELSA_temp_2_1979-2013_V1.2_land.tif
> > Size is 43200, 20880
> > [...]
> > Origin = (-180.000138888850017,83.999860415150010)
> > Pixel Size = (0.008333333300000,-0.008333333300000)
> >
> > Corner Coordinates:
> > Upper Left  (-180.0001389,  83.9998604) (180d 0' 0.50"W, 83d59'59.50"N)
> > Lower Left  (-180.0001389, -90.0001389) (180d 0' 0.50"W, 90d 0' 0.50"S)
> > Upper Right ( 179.9998597,  83.9998604) (179d59'59.49"E, 83d59'59.50"N)
> > Lower Right ( 179.9998597, -90.0001389) (179d59'59.49"E, 90d 0' 0.50"S)
> > Center      (  -0.0001396,  -3.0001392) (  0d 0' 0.50"W,  3d 0' 0.50"S)
> > Band 1 Block=43200x1 Type=Float32, ColorInterp=Gray
> >   NoData Value=-99999
> >
> > best,
> > Vero
>
> yes, AFAIK they're still working on it.
>
> tested here ver.1.2 with r.in.gdal trunk and
>
> -a
>     Auto-adjustment for lat/lon
>     Attempt to fix small precision errors in resolution and extents
>
> it seems to give good results.
>
>
>
>
> -----
> best regards
> Helmut
> --
> View this message in context: http://osgeo-org.1560.x6.
> nabble.com/CHELSA-climate-data-set-tp5284115p5319124.html
> Sent from the Grass - Users mailing list archive at Nabble.com.
> _______________________________________________
> grass-user mailing list
> grass-user at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/grass-user
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/grass-user/attachments/20170502/24a5d695/attachment.html>