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John, The OMEG values (V component of circ) will be in mb/sec. Circ returns a vector whose U component is the tangential component of V (in your case age()) and the V component is the vertical motion. The cross sectional representation of the vectors will be scaled be the aspect ratio of the plot due to the scale exaggeration between the horizontal and vertical distances on a plot. To see what the values of the V component (aka omeg) are, GFUNC = vr(circ(age,omeg)) SCALE = for todays' eta running CXSTNS = den>bna, shows: Grid file: $HDS/1999051012_eta_grid211.gem Date/time: f000 Vertical coordinate: pres Grid function: vr(circ(age,omeg)) Vector function: circ(age,omeg) Endpoints: den>bna Number of points: 21 Scaling factor: 10** 3 Panel: 0 LEVELS: -4.00 -2.00 0.00 2.00 4.00 COLORS: 3 3 3 3 3 LINTYP: 1 1 1 1 1 LINWID: 1 1 1 1 1 LABEL: 1 1 1 1 1 When scale is set to "blank" so the program picks its own, you see that the omeg values range from -4 x10-3 to 4x10-3 mb/sec (or roughly -4 to 4 microbars per second). If you set SCALE=0, you see that the range is -.004 to .004 mb/sec which is equivalent to the above -4 to 4 microbars. Since the units aren't actually m/s, it really makes more since to denote the vector with wind = bn rather than wind=bm. Steve Chiswell Unidata User SUpport On Mon, 10 May 1999, John Egentowich wrote: > Steve, > I have a quick gempak question. When I create cross sections to include > ageostrophic winds using "circ(age,omeg)" and displaying wind barbs in m/s -- > > are the vertical speeds scaled up? I get cross sections that have great > looking > ageo circulations however the vertical wind speeds are unreasonable. In > "quiet" > environments (without convection) I have vertical ageo wind speeds of 10-20 > m/s. > That can't be right unless the vertical component is scale up. Please > enlighten > me. Thanks for your help. > John > > ---------------------------------- > E-Mail: John Egentowich <address@hidden> > Date: 10-May-99 Time: 07:29:37 > Phone: 919-515-1437 > --------------------------------- >