Dylan wrote: > I would be interested in the result, and happy to test. maybe testing is as easy as running the test for elevation.10m in the spearfish dataset, or the r.volcano example from the r.sun wiki page http://grass.osgeo.org/wiki/R.sun with lin=1.0, and checking the value you pointed out in the r.info metadata?
> Any tips on getting started with the coef maps and GRIB > (not sure what that is)? GRIB is "GRIdded Binary", and is the standard output raster format for atmospheric/wave model forecast data. GDAL can read it (although AFAIK /still/ suffers from a 1/2 cell grid registration bug so needs a r.region correction after import) Interfacing with that data is parthly what I wrote d.barb to work with, although d.rast.arrow will partly do the job as well. Other free software like zyGrib.org and OpenCPN.org can be used to visualize it. I've just now written up a 5 minute quickstart for using zygrib, see the link at the end of this page: http://adhoc.osgeo.osuosl.org/livedvd/docs/en/overview/zygrib_overview.html zygrib does a really nice job of animating cloud cover, give it a try! how how to translate that to the beam and diffuse coefficients for r.sun ... hmmm ... well I guess the beam value would be the opacity of the cloud ceiling, and diffuse would be the opacity of the fog. The man page says they want to be scaled from 0.0-1.0, and r.rescale can do that from the r.in.gdal'd GRIB data. I assume 0.0 is clear sky but I'm not sure what 1.0 would be equivalent to.. a grim black sky as you might get under a thundercloud? Probably just the GRIB file's cloud-cover max is highly variable and not appropriate. Hamish _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
