Kriging...

[Don Newcomb]

>From: chris at mqatmos.cic.mq.edu.au (Chris Skelly)
>I am doing some research into global precipitation climatologies
>and need an interpolator that will allow me to estimate areal 
>precipitation from rain-guage data.  Being climatological I
>have to do this in the presence of a trend.  Additionally,
>I need some estimate of the spatial error involved in the
>interpolation.  It appears that Kriging is my best bet so I
>have embarked on creating a Universal Block Kriging routine
>with multiple semivariogram model options for GRASS (This
>ought to be good...as it is my first GRASS programming attempt!).

I am wondering about the usefulness of Thiessen Polygons in your
project. There are several programs available (not in GRASS though)
that form TPs about sparse sample points such as rain gauges. Once
the TPs are formed, many spatial calculations can be run on the
raster space.

 Donald R. Newcomb                     U.S. Naval Oceanographic Office
 newcomb at navo.navy.mil                 Stennis Space Center, MS 39522
 newcomb@{pops|q-aais}.navo.navy.mil   Voice: 601.688.5998
                                       FAX:   601.688.5485