;----------------------------------------------------------------------
; stream_1.ncl 
;
; Concepts illustrated:
;   - Drawing a black-and-white streamline plot over a map
;------------------------------------------------------------------
begin
;---Read in 2D data only
  f = addfile("T62_ncep_wind.nc","r")
  u = f->U_GRD_2_ISBL(0,0,:,:)                ; read in example data [2D only here]
  v = f->V_GRD_2_ISBL(0,0,:,:)
  wks  = gsn_open_wks("png","stream")                  ; send graphics to PNG file

  res                 = True                           ; plot mods desired
  res@tiMainString    = "Test" ; title
  res@mpMinLonF          = 80.    
  res@mpMaxLonF          = 240.
  res@mpMinLatF          = -5.           
  res@mpMaxLatF          = 50.

  res@stMinArrowSpacingF = 0.01         ; arrow spacing.
  res@stArrowLengthF     = 0.01           ; changes the size of the arrows.
  res@stLineThicknessF   = 1.5            ; changes the line thickness
  res@stLineColor        = "blue"       ; changes color

  plot = gsn_csm_streamline_map_ce(wks,u,v,res)
end