begin
;---Generate 6 dummy data sets
  nx    = 100
  ny    = 100
  data1 = generate_2d_array( 9, 10, -19.,16., 0, (/ny,nx/))
  data2 = generate_2d_array(10, 10, -20.,17., 3, (/ny,nx/))
  data3 = generate_2d_array(11, 12, -18.,19., 1, (/ny,nx/))

  wks = gsn_open_wks("x11","panel")    ; send graphics to PNG file

  res                      = True
  res@cnFillOn             = True
  plot1 = gsn_csm_contour(wks,data1,res)

  plot2 = plot1   ; make a copy of plot1, BAD WAY

;---Note, we're changing the color in plot #2, but redrawing plot #1!!!!
  setvalues plot2
    "cnFillPalette" : "BlueRed"
  end setvalues

  draw(plot1)    ; Color map has changed but labelbar has not!
  frame(wks)

end