<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
Hi Andrew,<br>
<br>
you can remap the data using gdal or cdo for instance. I prefer
using cdo and in the following the way to do it with cdo is
described.<br>
<br>
1. get grid description from input file<br>
2. change the units of x and y coordinate variable from 'Meter' to
'm'<br>
3. generate the grid description file for the output data on regular
lonlat grid for Puerto Rico area<br>
4. remap the input file<br>
<br>
Sounds difficult but it isn't.<br>
<br>
1. get the input file grid description<br>
<br>
<font face="monospace">cdo griddes nws_precip_wytd_20240601_pr.nc
> gridfile.txt</font><br>
<br>
2. edit the gridfile.txt and change Meter to m<br>
<br>
<font face="monospace">gridtype = projection<br>
gridsize = 42025<br>
xsize = 205<br>
ysize = 205<br>
xname = x<br>
xlongname = "x coordinate of projection"<br>
xunits = "m"<br>
yname = y<br>
ylongname = "y coordinate of projection"<br>
yunits = "m"<br>
xfirst = 4943283.5160097<br>
xinc = 4762.5<br>
yfirst = -6236964.62846119<br>
yinc = -4762.5<br>
grid_mapping = crs<br>
grid_mapping_name = polar_stereographic<br>
straight_vertical_longitude_from_pole = -105.<br>
false_easting = 0.<br>
standard_parallel = 60.<br>
false_northing = 0.<br>
latitude_of_projection_origin = 90.<br>
earth_radius = 6367470.<br>
proj4 = "+proj=stere +lat_0=90 +lat_ts=60 +lon_0=-105 +x_0=0
+y_0=0 +a=6367470 +b=6367470 +units=m +no_defs"<br>
crs_wkt = 'PROJCS["NOAA_HRAP_Grid",
GEOGCS["GCS_NOAA_HRAP", DATUM["D_NOAA_HRAP",
SPHEROID["Sphere",6367470,0.0] ],
PRIMEM["Greenwich",0.0],
UNIT["Degree",0.0174532925199433] ],
PROJECTION["Polar_Stereographic"],
PARAMETER["false_easting",0.0],
PARAMETER["false_northing",0.0],
PARAMETER["central_meridian",-105.0],
PARAMETER["latitude_of_origin",60.0], UNIT["meter",1.0]]'<br>
esri_pe_string = 'PROJCS["NOAA_HRAP_Grid",
GEOGCS["GCS_NOAA_HRAP", DATUM["D_NOAA_HRAP",
SPHEROID["Sphere",6367470,0.0] ],
PRIMEM["Greenwich",0.0],
UNIT["Degree",0.0174532925199433] ],
PROJECTION["Stereographic_North_Pole"],
PARAMETER["false_easting",0.0],
PARAMETER["false_northing",0.0],
PARAMETER["central_meridian",-105.0],
PARAMETER["standard_parallel_1",60.0], UNIT["meter",1.0]]'</font><br>
<br>
3. generate output grid descption file grid_lonlat.txt<br>
<br>
<font face="monospace">gridtype = lonlat<br>
gridsize = 31122<br>
xsize = 182<br>
ysize = 171<br>
xname = lon<br>
xlongname = "longitude"<br>
xunits = "degrees_east"<br>
yname = lat<br>
ylongname = "latitude"<br>
yunits = "degrees_north"<br>
xfirst = -70.6<br>
xinc = 0.05<br>
yfirst = 13.78<br>
yinc = 0.05</font><br>
<br>
4. remap the data<br>
<br>
<font face="monospace">cdo -remapbil,grid_lonlat.txt
-setgrid,gridfile.txt nws_precip_wytd_20240601_pr.nc outfile.nc</font><br>
<br>
<br>
Hope this will help you,<br>
Karin<br>
<br>
<br>
<div class="moz-cite-prefix">Am 01.06.24 um 22:15 schrieb Andrew
Kren - NOAA Federal via ncl-talk:<br>
</div>
<blockquote type="cite"
cite="mid:CAJJ=ypp7858o4czZ=A4uwW5kzOfxh60XSZ9r5sDVYHROx=uZKQ@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="ltr">Hi there,
<div><br>
</div>
<div>I am not sure I am asking the right question, but here
goes. I am reading noaa stage IV precipitation data, found
here: <a
href="https://water.noaa.gov/resources/downloads/precip/stageIV/2024/06/01/"
moz-do-not-send="true" class="moz-txt-link-freetext">https://water.noaa.gov/resources/downloads/precip/stageIV/2024/06/01/</a></div>
<div><br>
</div>
<div>The new data has been transformed to a polar stereographic
grid. When I did an ncl_filedump on the netcdf file, the
variables were x, y and not lat/lon. The x, y values are
random positive/negative numbers, which I'm guessing is some
non lat/lon projection. My question is, is there a way in NCL
to convert this file so that the variables are in lat/lon
coordinates? Or is this something I need to do outside ncl?</div>
<div><br>
</div>
<div>Thanks for any help!<br clear="all">
<div><br>
</div>
<span class="gmail_signature_prefix">-- </span><br>
<div dir="ltr" class="gmail_signature"
data-smartmail="gmail_signature">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<pre cols="72"
style="white-space:pre-wrap;color:rgb(34,34,34);font-family:"arial black",sans-serif"><span
style="font-family:arial,helvetica,sans-serif">Andrew Kren
Meteorologist
NOAA's National Weather Service
Raleigh Forecast Office
1005 Capability Drive, Suite 300
Raleigh, North Carolina 27606
voice: 919-326-1035
mailto: <a href="mailto:andrew.kren@noaa.gov" target="_blank"
moz-do-not-send="true" class="moz-txt-link-freetext">andrew.kren@noaa.gov</a></span><span
style="font-family:arial,helvetica,sans-serif">
</span><a href="http://www.weather.gov/rah" style="color:rgb(17,85,204)"
target="_blank"
moz-do-not-send="true"><span
style="font-family:arial,helvetica,sans-serif">http://www.weather.gov/rah</span></a></pre>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
ncl-talk mailing list
<a class="moz-txt-link-abbreviated" href="mailto:ncl-talk@mailman.ucar.edu">ncl-talk@mailman.ucar.edu</a>
List instructions, subscriber options, unsubscribe:
<a class="moz-txt-link-freetext" href="https://mailman.ucar.edu/mailman/listinfo/ncl-talk">https://mailman.ucar.edu/mailman/listinfo/ncl-talk</a>
</pre>
</blockquote>
<br>
</body>
</html>