Error in Color Polar Plot

Hello.

I'm trying to make a panel plot of streamline polar plots with color
contour for wind speed for the both hemispheres.
But when I plotted it, color plot didn't work as I expected (please
see the attached png image).
In the north hemisphere plot, color did work only a portion of the
longitude (0-130 deg).
In the south hemisphere, only one color displayed regardless of the wind speed.

Results are the same when I did not use the panel plot.

I'm using NCEP/NCAR Reanalysis data.

Thank you for your help in advance.

Jinwoong Yoo

LSU

Here goes my NCL code:

;*************************************************
; NCL Graphics: polar_2.ncl
;
; Concepts illustrated:
; - Drawing black-and-white contours over a polar stereographic map
; - Drawing the northern hemisphere of a polar stereographic map
;
;************************************************
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"

;************************************************
begin
;************************************************
; read in netCDF file

a = addfile("~/data/uwnd.2005.nc", "r")
b = addfile("~/data/vwnd.2005.nc", "r")

u850=short2flt(a->uwnd(:,2,:,:))
v850=short2flt(b->vwnd(:,2,:,:))

u850!1="lat"
u850!2="lon"
v850!1="lat"
v850!2="lon"

u850&lat@units="degrees_north"
u850&lon@units="degrees_east"
v850&lat@units="degrees_north"
v850&lon@units="degrees_east"

; calculate calendar date using ut_calendar(u&time,0)
; date(i,0)= year
; date(i,1)= month
; date(i,2)= day
; date(i,3)= hour
  date = ut_calendar(u850&time,0)
  ntime = dimsizes(u850(:,0,0)) ; Get number of timesteps.

;*************************************************
; calculate wind speed
;*************************************************
speed=sqrt(u850^2+v850^2)

;************************************************
; create plot
;************************************************
  wks = gsn_open_wks("ps","Polar"); open a ps file
  gsn_define_colormap(wks,"BlAqGrYeOrRevi200") ; choose color map
do i= 0,0;ntime-1
  res = True ; plot mods desired
  res@gsnFrame = False ; Do not draw plot
  res@gsnDraw = False ; Do not advance frame

  res@cnFillOn = True ; turn on color for contours
  res@cnLinesOn = False ; turn off contour lines
  res@cnLineLabelsOn = False ; turn off contour line labels
  res@cnLevelSelectionMode = "ExplicitLevels" ; Explicitly set
  res@cnLevels = ispan(0,50,2)
  res@lbLabelAutoStride = True

  res@gsnSpreadColors = True ; use full color map
  res@gsnSpreadColorStart = 17 ; start at color 17
  res@gsnSpreadColorEnd = 200 ; end at color 200

  res@tiMainString = date(i,1)+" "+date(i,2)+" 2005 at
"+date(i,3)+" h" ; plot title
  res@gsnLeftString = "Windspeed at 850 hPa"
  res@gsnRightString = "m/s"

  res@mpFillOn = False ; set land to be gray
  res@mpGeophysicalLineThicknessF = 1.2
  res@mpCenterLonF = -60

  res@lbOrientation = "Vertical" ; vertical label bar
  res@pmLabelBarOrthogonalPosF = 0.02 ; move label bar closer
  res@lbLabelStride = 2

  res@stArrowStride = 1 ; arrows start every third

  res@stMinArrowSpacingF = 0.075;0.05 ; arrow spacing.
  res@stArrowLengthF = 0.01 ; changes the size of the arrows.
  res@stLineThicknessF = 0.5 ; changes the line thickness
  res@stLineColor = "black" ; changes color

  plot=new(2,graphic) ; create graphic array

  res@gsnPolar = "NH" ; select the N. Hem.
  plot(0) = gsn_csm_streamline_contour_map_polar(wks,u850(i,:,:),v850(i,:,:),speed(i,:,:),res)

  delete(res@gsnPolar) ; delete previous option
  res@gsnPolarSH = True ; specify the hemisphere
  plot(1) =gsn_csm_streamline_contour_map_polar(wks,u850(i,:,:),v850(i,:,:),speed(i,:,:),res)
;***********************************************
; create panel plot
;***********************************************
  pres = True ; panel plot mods desired
  pres@gsnPanelYWhiteSpacePercent = 1 ; increase white space around
                                                ; indiv. plots in panel
  pres@gsnMaximize = True ; fill the page

  gsn_panel(wks,plot,(/2,1/),pres) ; create panel plot
end do

end

_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk