I’m a student majoring in meteorology
I’m trying to draw a weather chart using ncl, but I’m having two problems

The first question is that the High and Low labels are not drawn
No matter how much I change the overlap setting, it won’t be drawn on my picture

The second problem is that I use the Lambert conformal projection, so I used the tick marker code provided on the official website of ncl

But there’s no space between tick marker and painting

Below is my code

  1 load "add_map_tickmarks.ncl"
  2 
  3 files := systemfunc("ls /home/shlee/2024_KIAPS/KIM_4.0.07/ne090np3_REAL_CASE/6hour_data/")
  4 
  5 nfile = dimsizes(files)
  6 dates = new(nfile, string)
  7 
  8 explist = new(nfile, string)
  9 
 10 do j = 0, nfile-1
 11   dates(j) = str_get_field(files(j), 2, "-")
 12   dates(j) = str_get_field(dates(j), 1, ".")
 13 end do
 14 
 15 ;------------------------------------------------------------------------------
 16 ; resource
 17 ;------------------------------------------------------------------------------
 18 
 19 res = True
 20 
 21 res@gsnMaximize = True
 22 
 23 ;--- contour -------------------------------------------------------------------
 24 ;res@cnHighLowLabelOverlapMode = "OmitOverVPAndHL"
 25 
 26 
 27 res@cnLabelDrawOrder     = "PostDraw"
 28 
 29 res@cnFillOn             = False
 30 res@cnLinesOn            = True
 31 
 32 res@cnLevelSelectionMode = "ExplicitLevels"
 33 res@cnLevels = ispan(4700, 6200, 30)
 34 
 35 res@cnLineColor = "blue"
 36 res@cnLineLabelFontColor = "blue"
 37 res@cnLineThicknessF = 1.15
 38 res@cnLineLabelInterval = 2
 39 res@cnLineLabelPlacementMode = "constant"
 40 
 41 res@cnInfoLabelOn = False
 42 
 43 res@gsnFrame = False
 44 res@gsnDraw  = False
 45 
 46 res@mpDataBaseVersion = "MediumRes"
 47 res@mpDataSetName = "Earth..1"
 48 ;--- string -------------------------------------------------------------------
 49 res@gsnRightString = ""
 50 res@gsnLeftString = ""
 51 
 52 ;--- map plot -----------------------------------------------------------------
 53 res@mpOutlineOn = True
 54 res@mpOutlineBoundarySets = "AllBoundaries"
 55 
 56 res@mpLimitMode = "LatLon"
 57 
 58 res@mpMinLonF = 77.0
 59 res@mpMaxLonF = 160.0
 60 res@mpMinLatF = 12.5
 61 res@mpMaxLatF = 60.0
 62 
 63 res@mpOceanFillColor = "lightcyan"
 64 res@mpLandFillColor = "lightyellow1"
 65 res@mpGeophysicalLineThicknessF = 2
 66 
 67 res@mpProjection = "LambertConformal"
 68 res@mpLambertParallel1F = 35.
 69 res@mpLambertParallel2F = 45.
 70 res@mpLambertMeridianF = 125.
 71 
 72 
 73 res@mpGridAndLimbOn = True
 74 res@mpGridLineThicknessF = 0.8
 75 res@mpGridSpacingF = 10.0
 76 
 77 ;--- figure ratio -------------------------------------------------------------
 78 res@mpShapeMode = "FreeAspect"
 79 res@vpWidthF = 0.9
 80 res@vpHeightF = 0.65
 81 
 82 res@pmTickMarkDisplayMode = "Always"
 83 
 84 
 85 ;--- Temperature contour resource --------------------------------------------
 86 temres = True
 87 
 88 temres@gsnMaximize = True
 89 temres@gsnDraw = False
 90 temres@gsnFrame = False
 91 
 92 temres@cnFillOn             = True
 93 temres@cnLinesOn            = False
 94 temres@cnFillPallete        = "MPL_rainbow"
 95 
 96 ;temres@cnLevelSelectionMode = "ExplicitLevels"
 97 ;temres@cnLevels = ispan(4700, 6200, 30)
 98 
 99 res@cnInfoLabelOn = False
100 
101 ;------------------------------------------------------------------------------
102 ; plot
103 ;------------------------------------------------------------------------------
104 
105 ;do i = 0, nfile-1
106 do i = 0, 40
107   wks = gsn_open_wks("png", "./REAL_FCST_hgt_rain_" + dates(i))
108 
109   dash_pattern = (/"$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_$_"/)
110   new_dash = NhlNewDashPattern(wks, dash_pattern)
111 
112   res@mpGridLineDashPattern = new_dash
113 
114   res@cnHighLabelsOn = True
115   res@cnHighLabelFontHeightF = 0.03
116   res@cnHighLabelBackgroundColor = -1
117   res@cnHighLabelFontColor = "blue"
118 
119   res@cnLowLabelsOn = True
120   res@cnLowLabelFontHeightF = 0.015
121   res@cnLowLabelBackgroundColor = -1
122   res@cnLowLabelFontColor = "red"
123   ncfile = addfile("/home/shlee/2024_KIAPS/KIM_4.0.07/ne090np3_REAL_CASE/post/REAL_post_" 
124                    + dates(i) + ".nc", "r")
125 
126   hgt = ncfile->hgt(0,13,:,:)
127   t = ncfile->T(0,13,:,:)
128 
129   plot = gsn_csm_contour_map(wks, hgt, res)
130 
131   ;--- tick marker resource -----------------------------------------------------
132   tmres = True
133 
134   tmres@tmXBValues = ispan(90, 150, 10)
135   tmres@tmXTValues = (/ 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, -170, -160/)
136   tmres@tmYLValues = ispan(10, 40, 10)
137   tmres@tmYRValues = ispan(10, 50, 10)
138 
139   tmYUseLeft = False
140   tmXUseBottom = False
141 
142   tmres@tmXBLabelFontHeightF = 0.008
143   res@tmXBMajorLengthF = 0.001
144   res@tmXTMajorLengthF = 0.001
145   res@tmYLMajorLengthF = 0.001
146   res@tmYRMajorLengthF = 0.001
147 
148   tmres@tmXBMajorLengthF = 0.001
149   tmres@tmXTMajorLengthF = 0.001
150   tmres@tmYLMajorLengthF = 0.001
151   tmres@tmYRMajorLengthF = 0.001
152   map = add_map_tickmarks2(wks, plot, tmres)
153 
154   maximize_output(wks, True)
155 
156 
157 end do

  1 undef("add_map_tickmarks2")
  2 function add_map_tickmarks2(wks,plot,res)
  3 local res2, bres, vpx, vpy, vpw, vph, xndc, yndc, npts, n, j, nlat, 
  4 nlon, delta, bot_lon, top_lon, lft_lat, rgt_lat, xblabels, xbvalues, 
  5 xtlabels, xtvalues, yllabels, ylvalues, yrlabels, yrvalues, xfix, 
  6 xlat, xlon, yfix, annoid, anno_str
  7 begin
  8 ;---Make a copy of the original resource list.
  9   res2 = res
 10 
 11 ;---Retrieve edges of plot in NDC space.
 12   getvalues plot
 13      "vpXF"      :  vpx
 14      "vpYF"      :  vpy
 15      "vpWidthF"  :  vpw
 16      "vpHeightF" :  vph
 17   end getvalues
 18 
 19 ;---Turn off tickmarks associated with map. We want to add our own.
 20   setvalues plot
 21     "pmTickMarkDisplayMode" : "Never"
 22   end setvalues
 23 
 24 ;---Initialize resources for tickmark plot. User shouldn't change these.
 25   bres                          = True
 26   bres@vpXF                     = vpx
 27   bres@vpYF                     = vpy
 28   bres@vpWidthF                 = vpw
 29   bres@vpHeightF                = vph
 30   bres@trXMinF                  = vpx
 31   bres@trXMaxF                  = vpx + vpw
 32   bres@trYMinF                  = vpy - vph
 33   bres@trYMaxF                  = vpy
 34   bres@tmEqualizeXYSizes        = True
 35 
 36 ;---This resource the user can change in main code if desired.
 37   bres@gsnTickMarksPointOutward = get_res_value(res2,"gsnTickMarksPointOutward",True)
 38 
 39 ;
 40 ; NDC Points to scan on X and Y axes. These arrays will be used to
 41 ; find the closest NDC pair that gets us close to the location where
 42 ; we want a tickmark.
 43 ;
 44   npts = 100000   ; Increase to get closer match for tickmarks
 45   xndc = fspan(vpx,vpx+vpw,npts)
 46   yndc = fspan(vpy-vph,vpy,npts)
 47 
 48   n    = dimsizes(yndc)
 49   xfix = new(n,float)
 50   yfix = new(n,float)
 51   xlon = new(n,float)
 52   xlat = new(n,float)
 53   delta = 0.001
 54 
 55 ;---Left axis tickmarks
 56   if(isatt(res2,"tmYLValues")) then
 57     lft_lat    = get_res_value(res2,"tmYLValues",-1)
 58     nlat       = dimsizes(lft_lat)
 59     ylvalues = new(nlat,float)
 60     yllabels = new(nlat,string)
 61     xfix  = vpx + 0.0001 ; Just a smidge into the plot to make sure we don't
 62                          ; get missing values returned.
 63 ;
 64 ; Loop across each left latitude value that we want a tickmark for,
 65 ; and try to find the closest X,Y NDC coordinate pair along this axis.
 66 ;
 67     NhlNDCToData(plot,xfix,yndc,xlon,xlat)
 68     do j=0,dimsizes(lft_lat)-1
 69       NhlNDCToData(plot,xfix,yndc,xlon,xlat-0.001)
 70       ii = minind(fabs(xlat-lft_lat(j)))
 71       if(.not.any(ismissing(ii)).and.fabs(xlat(ii)-lft_lat(j)).le.delta)
 72         yllabels(j) = fabs(lft_lat(j)) + ""
 73         ylvalues(j) = yndc(ii(0))
 74         if(lft_lat(j).lt.0) then
 75           yllabels(j) = yllabels(j) + "~S~o~N~S"
 76         end if
 77         if(lft_lat(j).gt.0) then
 78           yllabels(j) = yllabels(j) + "~S~o~N~N"
 79         end if
 80       end if
 81       delete(ii)
 82     end do
 83     bres@tmYLMode   = "Explicit"
 84     bres@tmYLValues = ylvalues
 85     bres@tmYLLabels = get_res_value(res2,"tmYLLabels",yllabels)
 86   else
 87     bres@tmYLOn       = False
 88     bres@tmYLLabelsOn = False
 89   end if
 90 
 91 ;---Right axis tickmarks
 92   if(isatt(res2,"tmYRValues")) then
 93     rgt_lat    = get_res_value(res2,"tmYRValues",-1)
 94     nlat       = dimsizes(rgt_lat)
 95     yrvalues = new(nlat,float)
 96     yrlabels = new(nlat,string)
 97 
 98     xfix  = vpx + vpw - 0.0001 ; Just a smidge into the plot to make sure we don't
 99                                ; get missing values returned.
100 ;
101 ; Loop across each right latitude value that we want a tickmark for,
102 ; and try to find the closest X,Y NDC coordinate pair along this axis.
103 ;
104     do j=0,dimsizes(rgt_lat)-1
105       NhlNDCToData(plot,xfix,yndc,xlon,xlat)
106       ii = minind(fabs(xlat-rgt_lat(j)))
107       if(.not.any(ismissing(ii)).and.fabs(xlat(ii)-rgt_lat(j)).le.delta)
108         yrlabels(j) = fabs(rgt_lat(j)) + ""
109         yrvalues(j) = yndc(ii(0))
110         if(rgt_lat(j).lt.0) then
111           yrlabels(j) = yrlabels(j) + "~S~o~N~S"
112         end if
113         if(rgt_lat(j).gt.0) then
114           yrlabels(j) = yrlabels(j) + "~S~o~N~N"
115         end if
116       end if
117       delete(ii)
118     end do
119     bres@tmYROn       = True
120     bres@tmYRLabelsOn = True
121     bres@tmYUseLeft   = False
122     bres@tmYRMode     = "Explicit"
123     bres@tmYRValues   = yrvalues
124     bres@tmYRLabels   = get_res_value(res2,"tmYRLabels",yrlabels)
125   else
126     bres@tmYUseLeft   = False
127     bres@tmYROn       = False
128     bres@tmYRLabelsOn = False
129   end if
130 
131 ;---Top axis tickmarks
132   if(isatt(res2,"tmXTValues")) then
133     top_lon    = get_res_value(res2,"tmXTValues",-1)
134     nlon       = dimsizes(top_lon)
135     xtvalues = new(nlon,float)
136     xtlabels = new(nlon,string)
137 
138     yfix  = vpy - 0.0001 ; Just a smidge into the plot to make sure we don't
139                          ; get missing values returned.
140 ;
141 ; Loop across each top longitude value that we want a tickmark for,
142 ; and try to find the closest X,Y NDC coordinate pair along this axis.
143 ;
144     do j=0,dimsizes(top_lon)-1
145       NhlNDCToData(plot,xndc,yfix,xlon,xlat)
146       ii = minind(fabs(xlon-top_lon(j)))
147       if(.not.any(ismissing(ii)).and.fabs(xlon(ii)-top_lon(j)).le.delta)
148         xtlabels(j) = fabs(top_lon(j)) + ""
149         xtvalues(j) = xndc(ii(0))
150         if(top_lon(j).lt.0) then
151           xtlabels(j) = xtlabels(j) + "~S~o~N~W"
152         end if
153         if(top_lon(j).gt.0) then
154           xtlabels(j) = xtlabels(j) + "~S~o~N~E"
155         end if
156       end if
157       delete(ii)
158     end do
159     bres@tmXTOn       = True
160     bres@tmXTLabelsOn = True
161     bres@tmXUseBottom = False
162     bres@tmXTMode     = "Explicit"
163     bres@tmXTValues   = xtvalues
164     bres@tmXTLabels   = get_res_value(res2,"tmXTLabels",xtlabels)
165   else
166     bres@tmXUseBottom = False
167     bres@tmXTOn       = False
168     bres@tmXTLabelsOn = False
169   end if
170 
171 ;---Bottom axis tickmarks
172   if(isatt(res2,"tmXBValues")) then
173     bot_lon    = get_res_value(res2,"tmXBValues",-1)
174     nlon       = dimsizes(bot_lon)
175     xbvalues = new(nlon,float)
176     xblabels = new(nlon,string)
177 
178     yfix  = vpy-vph + 0.0001 ; Just a smidge into the plot to make sure
179                              ; we don't get missing values returned.
180 ;
181 ; Loop across each bottom longitude value that we want a tickmark for,
182 ; and try to find the closest X,Y NDC coordinate pair along this axis.
183 ;
184     do j=0,dimsizes(bot_lon)-1
185       NhlNDCToData(plot,xndc,yfix,xlon,xlat)
186       ii = minind(fabs(xlon-bot_lon(j)))
187       if(.not.any(ismissing(ii)).and.fabs(xlon(ii)-bot_lon(j)).le.delta)
188         xblabels(j) = fabs(bot_lon(j)) + ""
189         xbvalues(j) = xndc(ii(0))
190         if(bot_lon(j).lt.0) then
191           xblabels(j) = xblabels(j) + "~S~o~N~W"
192         end if
193         if(bot_lon(j).gt.0) then
194           xblabels(j) = xblabels(j) + "~S~o~N~E"
195         end if
196       end if
197       delete(ii)
198     end do
199     bres@tmXBMode   = "Explicit"
200     bres@tmXBValues = xbvalues
201     bres@tmXBLabels = get_res_value(res2,"tmXBLabels",xblabels)
202   else
203     bres@tmXBOn       = False
204     bres@tmXBLabelsOn = False
205   end if
206 
207 ;
208 ; Now that we are done figuring out where to put tickmarks, and
209 ; what labels to use, get any "tm" resources that might have been
210 ; set by the user, and create a blank plot with thes new tickmarks.
211 ;
212 
213 ;---Get rest of user resources that were set with "tm".
214   bres = get_res_eq(res2,"tm")
215 
216   bres = True   ; Above call will set bres to True if no "tm" resources, so
217                 ; make sure it is True still.
218 
219   bres@gsnDraw  = False
220   bres@gsnFrame = False
221 
222 ;
223 ; Create blank plot with new tickmarks (don't use gsn_csm_blank_plot,
224 ; because it wants to scale the size of your X and Y axes.)
225 ;
226   blank  = gsn_blank_plot(wks,bres)
227 
228 ;
229 ; Attach new tickmarks to original plot. This will allow resizing
230 ; if desired. The default is to attach one plot to the center of
231 ; the other one. These two plots are already the same size.
232 ;
233   annoid = gsn_add_annotation(plot,blank,False)
234 
235 ;
236 ; Be sure to return the annotation id, otherwise the
237 ; tickmarks will disappear.
238 ;
239   anno_str = unique_string("annoid")
240   plot@$anno_str$ = annoid
241 
242   return(plot)
243 end