[Gdal-dev] Reading GPCP rainfall data?
Frank Warmerdam
warmerdam at pobox.com
Tue Jul 11 13:25:06 EDT 2006
Markus Neteler wrote:
> Hi,
>
> I would be very interested to read these data sets
>
> Global Daily Merged Precipitation Analyses of the GPCP
> http://precip.gsfc.nasa.gov/
> (see Daily Data at page bottom)
>
> The Format is:
> http://precip.gsfc.nasa.gov/gpcp_daily_comb.html
> (at bottom)
> "The data set archive consists of unformatted REAL*4 binary files with ASCII headers. Each file holds 28-31 daily fields. Each file occupies about 8 MB. The grid on which each field of values is presented is a 1°x1° latitude--longitude (Cylindrical Equal Distance) global array of points. It is size 360x180, with X (longitude) incrementing most rapidly West to East from the Prime Meridian, and then Y (latitude) incrementing North to South. Whole- and half-degree values are at grid edges:
>
> First point center = (89.5°N,0.5°E)
> Second point center = (89.5°N,1.5°E)
> Last point center = (89.5°S,0.5°W)
>
> Missing values are denoted by the value -99999., and the units are mm/day.
> "
>
> Does anyone has experience? Or (cough) a script based on GDAL?
Markus,
I have attached a VRT that would reference one of these files. You could
likely produce these from a template with filename substitution in a script
pretty easily.
Best regards,
--
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush | President OSGF, http://osgeo.org
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