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<body class='hmmessage'><div dir='ltr'>Bailey,<br><br>It seems like you don't need geometric transformation of your images. We can see that your input is called reprojected. You just need to re-scale it, interpolating/filling it up with pixels values based on cubic method. <br><br>You can do that with gdal_translate -tr or -outsize parameters. <br><br>It should be faster since it requires less floating point computation on the warping/transformation.<br><br>But it could be that gdalwarp is smart enough to figure out that it doesn't need to do any transformation.<br><br>You can give it a try.<br><br>Regards,<br><br>Ivan<br><br><div><hr id="stopSpelling">From: bdmorri2@illinois.edu<br>To: gdal-dev@lists.osgeo.org<br>Date: Mon, 13 Jul 2015 17:12:02 +0000<br>Subject: [gdal-dev] Need to resample climate data to very fine resolution<br><br>
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<p class="ecxMsoNormal">Hello,</p>
<p class="ecxMsoNormal"> </p>
<p class="ecxMsoNormal">I am having issues using gdalwarp to resample climate data to a finer resolution. Each climate raster has been clipped to the extent of Alaska, and contain >300 layers (1 for every month from 1979-2010). The current resolution of the rasters
is >1000 km and they need to be resample to around 33 meters, making the new files go from ~8 MB to 33 GB. I have been testing out gdalwarp on these files but so far I cannot get them to resample in a reasonable amount of time. I ran one for over 15 hours
on my universities campus cluster and it never passed the 0% complete mark. I need to be able to get each file done in less then 48 hours since that is the time frame limit on the cluster.
</p>
<p class="ecxMsoNormal"> </p>
<p class="ecxMsoNormal">My current code is: gdalwarp /project/oa/akpaleo/climate/ccsm4/modern/reprojected/<span style="color:#3B4045;background:white;">pr_Amon_CCSM4_amip_r1i1p1_197901-201012.tif</span><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:#3B4045;background:white;">
–tr 33.945415050894333 33.945415050894333 –r “cubic” /projects/oa/akpaleo/climate/ccsm4/modern/resample/pr.tif
</span></p>
<p class="ecxMsoNormal"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:#3B4045;background:white;"> </span></p>
<p class="ecxMsoNormal"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:#3B4045;background:white;"> </span></p>
<p class="ecxMsoNormal"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:#3B4045;background:white;">I don’t know if I have written this out incorrectly to get the resample to work since I am new to gdal, but I believe this is correct.</span></p>
<p class="ecxMsoNormal"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:#3B4045;background:white;"> </span></p>
<p class="ecxMsoNormal"><span style="font-size:10.5pt;font-family:"Helvetica","sans-serif";color:#3B4045;background:white;">Does anyone know a reasonable way to speed this process up (or get around the time limit issue) correctly without causing incorrect calculations
to the output files? </span></p>
<p class="ecxMsoNormal"> </p>
<p class="ecxMsoNormal">I’ve attached a link to one of the climate rasters I am using.
</p>
<p class="ecxMsoNormal"> </p>
<p class="ecxMsoNormal"><a href="https://uofi.box.com/s/4cv7tvpnf29d70n9wb0a8t9y4oxmudql" target="_blank">https://uofi.box.com/s/4cv7tvpnf29d70n9wb0a8t9y4oxmudql</a>
</p>
<p class="ecxMsoNormal"> </p>
<p class="ecxMsoNormal"> </p>
<p class="ecxMsoNormal">Thank you,</p>
<p class="ecxMsoNormal"> </p>
<p class="ecxMsoNormal">Bailey Morrison</p>
<p class="ecxMsoNormal">PhD Student</p>
<p class="ecxMsoNormal">NASA Earth and Space Science Fellow</p>
<p class="ecxMsoNormal">University of Illinois at Urbana-Champaign</p>
<p class="ecxMsoNormal">Program in Ecology, Evolution, and Conservation Biology</p>
<p class="ecxMsoNormal">Global Environmental Analysis and Remote Sensing Lab (GEARS)</p>
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