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<p>Hi all, <br>
</p>
<p>I have an issue with a polar stereographic projection definition.</p>
<p>Context: I tried to open a NetCDF files in QGIS and with GDAL and
it failed with: <br>
</p>
<ul>
<li>Gdal:<i> ERROR 1: PROJ: proj_as_proj_string: Unsupported
conversion method: Polar_Stereographic</i></li>
<li>Qgis:<i> WARNING Could not reproject layer extent: Could not
transform bounding box to taret CRS<br>
</i></li>
</ul>
<p>The projection fails with the previous error for both gdal and
proj versions:</p>
<ul>
<li>GDAL 3.1.3, 3.3.0</li>
<li>PROJ 7.2.0, 8.01</li>
</ul>
<p>Test files (really any files in the folder will have the same
behavior): <br>
</p>
<ul>
<li><a class="moz-txt-link-freetext" href="https://dd.weather.gc.ca/model_giops/netcdf/polar_stereographic/2d/00/003/CMC_giops_votemper_depth_0.5_ps5km60N_3h-mean_">https://dd.weather.gc.ca/model_giops/netcdf/polar_stereographic/2d/00/003/CMC_giops_votemper_depth_0.5_ps5km60N_3h-mean_</a><b>{YYYYMMDDHH}</b>_P003.nc</li>
</ul>
<p>I tried opening the files with an older gdal/proj version and it
worked fine:</p>
<ul>
<li>GDAL: <font size="4"><code>2.4.4, released 2020/01/08</code></font></li>
<li>PROJ: Rel. 4.8.0, 6 March 2012</li>
</ul>
<p>Here is the projection definition I got: <i>+proj=stere
+lat_0=90 +lat_ts=59.99993768695209 +lon_0=-100 +k=0.93301243
+x_0=4245000 +y_0=5295000 +a=6371229 +b=6371229 +units=m
+no_defs</i></p>
<p>When I tried adding the projection manually in Qgis (3.20), I got
the following error message:</p>
<i>This proj projection definition is not valid:</i><i><br>
</i><i>proj_create: lat_ts != lat_0 and k != 1 not supported for
Polar Stereographic.</i><br>
<p>Should the projection definition be updated in the NetCDF files
if this really is not a supported projection definition anymore,
or is this a bug in gdal?<br>
</p>
<p>If this looks like a bug to you, let me know, I will open an
issue on the gdal repo.</p>
<p>Thanks!</p>
<p>LP<br>
</p>
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