[ncl-talk] Plotting Lat/Lon Points on a map
Tim Melino
melino33 at gmail.com
Sun May 28 06:32:58 MDT 2017
Hi Barry,
Here is the information when printing (a). Would the map projection also
cause a marker to be printed in the wrong location?
Variable: a
Type: file
filename: test
path: ./test.grib2
file global attributes:
dimensions:
lat_0 = 30
lon_0 = 40
variables:
float VAR_209_3_34_P0_L102_GLL0 ( lat_0, lon_0 )
center : US NOAA Office of Oceanic and Atmospheric Research
production_status : Research products
long_name : unknown variable name
units : unknown
_FillValue : 1e+20
grid_type : Latitude/longitude
parameter_discipline_and_category : 209, 3
parameter_template_discipline_category_number : ( 0, 209,
3, 34 )
level_type : Specific altitude above mean sea level (m)
level : 500
forecast_time : 0
forecast_time_units : minutes
initial_time : 07/09/2016 (04:46)
float lat_0 ( lat_0 )
long_name : latitude
grid_type : Latitude/Longitude
units : degrees_north
Dj : 0.01
Di : 0.009999676
Lo2 : 280.735
La2 : 36.695
Lo1 : 280.345
La1 : 36.405
float lon_0 ( lon_0 )
long_name : longitude
grid_type : Latitude/Longitude
units : degrees_east
Dj : 0.01
Di : 0.009999676
Lo2 : 280.735
La2 : 36.695
Lo1 : 280.345
La1 : 36.405
On Sun, May 28, 2017 at 12:48 AM, Barry Lynn <barry.h.lynn at gmail.com> wrote:
> Hi:
>
> When the data is skewed, it is often because the projection you're reading
> is not the one your plotting.
>
> Do you know the projection of the data you're using?
>
> If you print(a) where a is the file you specify from addfile, you can see
> the variables (and hopefully projection) indicated within.
>
> Barry
>
> On Sat, May 27, 2017 at 4:20 PM, Tim Melino <melino33 at gmail.com> wrote:
>
>> Hi,
>>
>> I am attempting to plot a subset of the MRMS data from NCEP. The
>> latitude and longitude I am plotting is :
>>
>> LAT: 36.5459089
>> LON: -79.4585847
>>
>> I attached an image of the output along with the grib file I am using for
>> input. I am noticing a couple things first the data appears to be skewed,
>> so I am not sure if it is an issue with the map projection. Second the
>> point which should be plotted in Virginia is actually plotted in North
>> Carolina, the only thing that I have been able to do if offset the marker
>> to compensate for the issue. Does anyone have any ideas on how to fix these
>> issues? Any ideas would be greatly appreciated!
>>
>> Thanks!
>> Tim
>>
>> Code:
>>
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
>>
>> begin
>>
>> lati=LAT
>> loni=LON
>> date=DATE
>> address=ADDRESS
>>
>>
>> ; Convert the Lat/Lon to a Float
>> latc= stringtofloat(lati)
>> lonc = stringtofloat(loni)
>>
>> ; Set the Map Bounds
>> minlat = latc - .12
>> maxlat = latc + .12
>> minlon = lonc - .15
>> maxlon = lonc + .15
>>
>>
>> ;========================
>> ; get list of all files and open as "one big file"
>> ;========================
>> a = addfile( "./" + lati + "_" + loni + ".grib2","r")
>>
>> type = "png"
>> wks = gsn_open_wks(type,"./" + lati + "" + loni + ".png")
>>
>> ; Set some Basic Plot options
>> res = True
>> res at gsnDraw = False ; do not draw the plot
>> res at gsnFrame = False ; do not advance the frame
>> pltres = True
>> pltres at NoTitles = True
>> pltres at CommonTitle = True
>> pltres at PlotTitle = ""
>> pltres at PanelPlot = True
>> pltres at FramePlot = False
>>
>> ; Set the Colormap
>> gsn_define_colormap(wks,"hail")
>> lat = a->lat_0
>> lon = a->lon_0
>> water = a->VAR_209_3_34_P0_L102_GLL0(:,:)
>> hail = water *0.0393701;
>>
>>
>> ; Plotting options for Hail
>> res at gsnMaximize = True
>> res at mpGeophysicalLineThicknessF = 4.0
>> ;res at mpProjection = "LambertConformal"
>> res at mpGridLineThicknessF = 0.5
>> res at mpLimbLineThicknessF = 4.0
>> res at mpNationalLineThicknessF = 4.0
>> res at mpUSStateLineThicknessF = 4.0
>> res at mpProvincialLineThicknessF = 4.0
>> res at mpOutlineBoundarySets = "AllBoundaries"
>> res at mpDataBaseVersion = "Ncarg4_1"
>> res at mpDataSetName = "Earth..4"
>> res at mpFillOn = False ; fill continents
>> res at mpPerimOn = False ; no box around map
>> res at tiMainOn = True
>> res at tiMainFontColor = "Black"
>> res at tiMainString =""
>> res at tiXAxisString = ""
>> res at tiYAxisString = ""
>> res at gsnLeftString = "Date: " + date ; add the gsn
>> titles
>> res at gsnRightString = ""
>> res at gsnStringFontHeightF = 0.016
>> res at cnInfoLabelOrthogonalPosF = 0.07 ; offset second label information
>> res at gsnContourLineThicknessesScale = 0.001
>> res at cnFillOn = True
>> res at lbTitleOn = True ; remove field
>> name from label bar
>>
>> ; Set the Map Bounds
>> res at sfYArray = lat
>> res at sfXArray = lon
>> res at mpLimitMode = "LatLon"
>> res at mpMinLatF = minlat
>> res at mpMaxLatF = maxlat
>> res at mpMinLonF = minlon
>> res at mpMaxLonF = maxlon
>> res at tmXBOn = False
>> res at tmYLOn = False
>> res at tmXTOn = False
>> res at tmYROn = False
>> res at gsnAddCyclic = False
>> res at tfDoNDCOverlay = False ; do not
>> transform data
>> res at cnLevelSelectionMode = "ExplicitLevels" ; set explicit
>> contour levels
>> res at cnLevels = (/ 0.5,0.75, 1.00, 1.25, 1.50, 1.75, 2.00,
>> 2.50, 3.00, 3.50, 4.00, 4.50, 5.00/) ; set levels
>> res at tiMainFontHeightF = 0.018 ; font height of
>> title
>> res at lbAutoManage = False ; we control label
>> bar
>> res at pmLabelBarDisplayMode = "Always" ; turns on label
>> bar
>> res at lbOrientation = "Horizontal" ; ncl default is
>> vertical
>> res at pmLabelBarSide = "Bottom" ; default is right
>> res at lbLabelStride = 1 ; skip every other
>> label
>> res at pmLabelBarWidthF = 0.7 ; default is
>> shorter
>> res at pmLabelBarHeightF = 0.1 ; default is taller
>> res at lbLabelFontHeightF = .012 ; default is HUGE
>> res at lbPerimOn = False ; default has box
>> res at lbTitleString = "Hail Size (Inches)"
>> res at lbTitleFontHeightF = 0.012
>> plot = gsn_csm_contour_map(wks,hail,res)
>>
>> ; Setup the point
>> mstring1 = "z"
>> fontnum1 = 35
>> xoffset1 = .4
>> yoffset1 = .7
>> ratio1 = 0.0
>> size1 = 1.0
>> angle1 = 0.0
>>
>> Tm_index = NhlNewMarker(wks, mstring1, fontnum1, xoffset1, yoffset1,
>> ratio1, size1, angle1)
>>
>> ; Plot the sites and label them
>> gres = True
>> gres at gsMarkerIndex = Tm_index ; 16
>> gres at gsMarkerSizeF = 0.015 ; .009
>> gres at gsMarkerColor = "black"
>> gres at txFont ="helvetica-bold"
>> gres at txFontHeightF = "25"
>>
>> site = (/address/)
>> lats = (/latc/)
>> lons = (/lonc/)
>>
>> dot = gsn_add_polymarker(wks,plot,lons,lats,gres)
>> tlats =lats + .03
>> tlons =lons
>> text = gsn_add_text(wks,plot,site,tlons,tlats ,gres)
>>
>> ; Draw the graphics
>> draw(plot)
>> frame(wks)
>>
>> end
>>
>>
>> _______________________________________________
>> ncl-talk mailing list
>> ncl-talk at ucar.edu
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
>>
>
>
> --
> Barry H. Lynn, Ph.D
> Senior Lecturer,
> The Institute of the Earth Science,
> The Hebrew University of Jerusalem,
> Givat Ram, Jerusalem 91904, Israel
> Tel: 972 547 231 170
> Fax: (972)-25662581
>
> C.E.O, Weather It Is, LTD
> Weather and Climate Focus
> http://weather-it-is.com
> Jerusalem, Israel
> Local: 02 930 9525
> Cell: 054 7 231 170
> Int-IS: x972 2 930 9525
> US 914 432 3108 <(914)%20432-3108>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170528/16a423f9/attachment.html
More information about the ncl-talk
mailing list