Vectors on polar stereographic plots

[Stephen Nash <s.d.nash@xxxxxxxxxxxxx>]

I am currently trying to produce some polar stereographic plots with 
vectors.  I have produced the same plots in a 'normal' projection and 
had no problems.  I have also been able to produce 'fill' plots on the 
stereographic plots with no problems.  However, when producing vector 
plots I only get arrows from regions where my measured field has its 
highest values.  At some point in the code it seems that the small 
values are being filtered out (and they're not that much smaller):

set mode metafile
use u10_2000_01_djf.cdf
set grid u10
let pi=4*atan(1)
let wind=((u10^2)+(v10^2))^0.5
let ang=atan(v10/u10)
let dir=if u10 gt 0 then ((pi/2)-ang) else (((3*pi)/2)-ang)
let Ts=(5.1e-4)*(wind^3)
let Tsx=Ts*sin(dir)
let Tsy=Ts*cos(dir)
set window/aspect=2
set viewport lower
set region/x=0:360/y=-90:0/l=1:90
go mp_stereographic_south
!fill/levels=(0,1.5,0.1)/nolab/title="Seasonally-Averaged Integrated 
Stokes Transport for DJF 2000/01 based on the math of McWilliams and 
Restrepo, Southern Hemisphere" Ts[t=0:1@ave]*mp_mask, x_page, y_page
vector/length=0.5 Tsx[t=0:1@ave]*mp_mask, 
Tsy[t=0:1@ave]*mp_mask,x_page,y_page
go mp_fland
label/nouser `($PPL$XLEN)*0.5`,-0.4,0,0,.05 Seasonally-Averaged 
Integrated Stokes Transport for DJF 2000/01 based on the math of 
McWilliams and Restrepo, Southern Hemisphere
set viewport upper
set region/x=0:360/y=0:90/l=1:90
go mp_stereographic_north
!fill/levels=(0,1.5,0.1)/nolab/title="Seasonally-Averaged Integrated 
Stokes Transport for DJF 2000/01 based on the math of McWilliams and 
Restrepo, Northern Hemisphere" Ts[t=0:1@ave]*mp_mask, x_page, y_page
vector/length=0.1 Tsx[t=0:1@ave]*mp_mask, Tsy[t=0:1@ave]*mp_mask, 
x_page, y_page
go mp_fland
label/nouser `($PPL$XLEN)*0.5`,-0.4,0,0,.05 Seasonally-Averaged 
Integrated Stokes Transport for DJF 2000/01 based on the math of 
McWilliams and Restrepo, Northern Hemisphere
cancel mode metafile

Hope someone can help!!

Thank you,

Stephen Nash




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Stephen Nash
Department of Meteorology
The University of Reading
Early Gate
PO BOX 243
Reading, RG6 6BB
s.d.nash@reading.ac.uk
07766075885
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