[GRASSLIST:3812] Re: interpolate rainfall - r.runoff

[Guillermo Felipe]

Thank you for the answers,

> > I have no idea what G-language is.
> Where did you find this reference?

In the manual...

NAME
r.runoff (G-language) Generates an SCS curve number runoff map layer. It is
a command-line interface for generating the runoff map by the SCS method.
SYNOPSIS
r.runoff rf=rainfall_map cn=cn_map ro=runoff_map

----- Original Message -----
From: "Markus Neteler" <neteler at itc.it>
To: <GRASSLIST at baylor.edu>
Sent: Friday, May 31, 2002 3:42 AM
Subject: [GRASSLIST:3802] Re: interpolate rainfall - r.runoff


> On Thu, May 30, 2002 at 06:48:15PM -0600, Roger Miller wrote:
> > On Thursday 30 May 2002 19:12, felipe wrote:
> >
> > > Hello list,
> > >
> > > What is the best method to interpolate rainfall maps in GRASS and/or
Linux?
> > >
> > > Something how kriging....
> >
> > I have used gstat ( http://www.gstat.org ) to produce GRASS raster maps
via
> > kriging.  Gstat offers a lot of capabilities, but the version I have is
> > fairly difficult to use and behaves badly with even moderate-sized
datasets.
> > With luck that has been improved.
>
> Another method is to use s.vol.rst if you interpolate in an area
> with non-flat elevations (refs: [1], [2])
>
> You need
>  - 3D sites of climate stations (x,y,z,attribs)
>  - 2D raster DEM
>
> The interpolation is done with 3D RST (3D splines) as provided by
> 's.vol.rst'.
>
> 's.vol.rst' expects you have defined 3D region (as every other 3D module).
> Therefore you have to run 'g3.createwind' script before 's.vol.rst'.
> It doesn't matter that you will produce just a 2D, intersection file.
> 's.vol.rst' asks for 3D region during the input (remember, you must have
> 3D sites file).
>
> With 'g3.setregion' you can change your vertical resolution to 3000m
> (i.e. define only one depth layer, s.vol.rst will be happy with that).
>
> The command line may be something like this:
>   s.vol.rst in=precip3d cellinp=dem500 cellout=precip.topo zmult=50
>
> The resulting map 'precip.topo' is a 2D raster map containing the
> precipitation. This precipitation was calculated internally with
> 3D Regularized Splines with Tension (RST). The 'cellinp' method
> extracts the precipitation values from the precipitation volume at
> the individual elevations as stored in the 'dem500' raster map.
>
> [1] Hofierka J., J. Parajka, H.  Mitasova, and L. Mitas, 2002. Modeling
>     impact of terrain on precipitation using 3-D spatial interpolation.
>     Transactions in GIS, March 2002, vol. 6, no. 2, pp. 135-150(16)
> [2] The upcoming GRASS book
>
> > > I need to generate some rainfall maps to scs runoff calculation.
> > >
> > > Where can I get the r.runoff code?
> > > What is G-language?
> >
> > r.runoff was part of grass4.  Documentation for r.runoff is still
included in
> > grass5, but I haven't been able to find the code.  You may be able to
get it
> > from a grass4 distribution or from somewhere deep in the Grass CVS tree,
but
> > I can't lead you to believe that it will work with Grass5.
>
> Check also:
> r.cn help
> Description:
>  Generates a SCS curve number map layer
>
> > I have no idea what G-language is.
> Where did you find this reference?
>
> Markus Neteler
>