vector and shade in curvilinear coordinates

[Arne Biastoch <abiastoch@xxxxxxxxxxxxxxx>]

Dear Ferreters,

plotting output of the ORCA2 model (global standard configuration of the 
OPA model) I tried to make use of the 3-argument versions of the shade 
and vector commands. The data are on a tripolar grid, latitude and 
longitude are therefore 2D fields (see attached grid.gif).

Plotting vectors using
	yes? vector u,v,lon,lat
works fine (land masks can easily and correctly be identified, see 
vector.gif).

But doing a shade (or fill) using
	yes? shade temp,lon,lat
gives distorted fields, only a small central regions seems to be ok (see 
shade.gif), outer regions are "fringed". I played around with the axes 
(modulo etc.), without any enhancement.

The actual construction of the figures is different for both commands: 
vectors are correctly drawn point by point, starting with indices 1,1 of 
lat,lon. In contrast the shade command is build up from south to north.

Any ideas from the experts and/or other ORCA/ferret users?

Cheers,
	Arne


--

Dr. Arne Biastoch

Institute for Marine Research         phone: ++49 431 600-4013
FB1 Ocean Circulation and Climate     fax  : ++49 431 600-1515
Duesternbrooker Weg 20                email: abiastoch@ifm.uni-kiel.de
24105 Kiel, Germany

http://www.ifm.uni-kiel.de/fb/fb1/tm/data/pers/abiastoch.html