[GRASS-dev] r.watershed2 with MFD

On Fri, Dec 5, 2008 at 1:55 AM, Markus Metz <markus_metz at gmx.de> wrote:

I took the request for MFD support in r.watershed by Helena and Dylan to
heart and implemented it, but still need a few more days to clean up the
code, then I want to submit it as r.watershed2.mfd to grass-addons.

A first result for flow accumulation is here:
http://markus.metz.giswork.googlepages.com/rw2_mfd_large.jpg
This output has been calculated from elev_lid1972_1m in the North

Carolina sample dataset.

Markus, this is absolutely amazing! I was just testing a new version of my erosion simulation module (r.landscape.evol) in whic I had incorporated the new r.watershed, and I was getting the “linear artifacts” that Helena mentioned in my long term (100 cycle) runs. I was experimenting with neighborhood median smoothing to amelorate these effects, and had just determined that a 5x5 median smoothing window worked the best, even though it adds ~12 seconds per cycle to the run time. But that may all be irrelevant now that you have implemented MFD into r.watershed! I can;t wait to test this new functionality of r.watershed in r.landscape.evol, I’m expecting it to produce fantastic results!

Cheers,

Isaac Ullah

Isaac I Ullah, M.A.

Archaeology PhD Student,
ASU School of Evolution and Social Change

Research Assistant,
Mediterranean Landscape Dynamics Project


isaac.ullah@asu.edu
ullah@archaeologist.com

http://www.public.asu.edu/~iullah