Large-data analysis in GRASS

[Rich Shepard]

On Thu, 28 Sep 2000, David Finlayson wrote:

> How well does GRASS handle very large data sets?

  The SWAT/GRASS combination was used to model the hydrology of the entire
lower 48 states of the US. IIRC, the country was partitioned into > 500
drainage basins and the number crunching took about two weeks on a new,
high-power Sun spark box.

  Bruce Byars at Baylor and Jeff Arnold at the Grasslands Ag Research
Station in Temple, TX can tell you more about it. I don't remember all the
details. But, the important point is that the amount of input data would
qualify under anyone's definition of "very large" and the number crunching
was serious.

  SWAT (Surface Water Assessment Tool) is a comprehensive basin hydrology
model that includes erosion and chemical/sediment dispersion as well as
water runoff. GRASS is used to prepare input data and display output. From
what you wrote, it's the add-on you need. See:
<http://dino.wiz.uni-kassel.de/model_db/mdb/swat.html> for a summary.

Rich

Dr. Richard B. Shepard, President

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