DKRZ NCL color map example - use named colors

Example script:

;-----------------------------------------------------------------------------------
; DKRZ NCL Example:  color_use_named_colors_for_colormap.ncl
;
; Description:   Demonstrate the use of named colors to define a color map.
;                Use the reversed color map of the upper plot for the lower
;                plot within the same frame.
;
;                Can be used with
;                  cnFillPalette colormap  to be used for a filled contour plot
;                  vcLevelPalette colormap to be used in a filled vector plot
;                  stLevelPalette colormap to be used in a filled streamlines plot
; 12.03.18 kmf
;-----------------------------------------------------------------------------------
begin
 f = addfile("./rectilinear_grid_2D.nc","r")
 var = f->tsurf(0,:,:)

 colors1 = (/"gray10","gray20","gray30","gray40","gray50","gray60","gray70",\
 "darkorange","darkorange1","darkorange2","darkorange3","darkorange4",\
 "chocolate4"/)
 colors2 = colors1(::-1)

;-- open workstation (frame)
 wks = gsn_open_wks("png","plot_color_use_named_colors_for_colormap")

;-- set common resources
 res = True
 res@gsnDraw = False
 res@gsnFrame = False
 res@gsnMaximize = True

 res@cnFillOn = True         ;-- turn on contour fill
 res@cnLinesOn = False       ;-- turn off contour lines
 res@cnLineLabelsOn = False  ;-- turn off line labels
 res@cnLevelSelectionMode = "ManualLevels" ;-- set contour levels manually
 res@cnMinLevelValF = 250.   ;-- minimum contour level
 res@cnMaxLevelValF = 310.   ;-- maximum contour level
 res@cnLevelSpacingF = 10.   ;-- contour level spacing

 res@lbLabelStride = 4
 res@lbBoxMinorExtentF = 0.15 ;-- decrease the height of the labelbar

 res@tiMainFontHeightF = 0.02

;-- draw the first plot in memory
 res@tiMainString = "Use named colors and cnFillPalette"  ;-- title string

 res@cnFillPalette = colors1  ;-- color map array

 plot1 = gsn_csm_contour_map(wks, var, res)

;-- draw the second plot in memory
 res@tiMainString = "Reverse the upper color map"  ;-- title string
 res@cnFillPalette = colors2  ;-- reversed color map colors1

 plot2 = gsn_csm_contour_map(wks, var, res)

;-- generate the panel and advance the frame
 gsn_panel(wks,(/plot1,plot2/),(/2,1/),True)

end

Result: