<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">There is a way to do this using a PDEF file, but it requires some external software tools to generate the interpolation weights and then to create the PDEF file itself. I set up a workflow to do this for CMIP5 ocean and sea ice variables, which are almost all on non-rectilinear grids. I use the ESMF tool called ESMF_RegridWeightGen to do the interpolation and get the weights, then I wrote a short C program called weights2pdef.c to transform the output from RegridWeightGen into a PDEF file for GrADS. Both tools require the netcdf library. The ESMF software is straightforward to build, and their help desk is excellent if you run into problems. Everything I have used for the CMIP5 data is here:<div><br></div><div><a href="ftp://cola.gmu.edu/pub/jma/cmip5/">ftp://cola.gmu.edu/pub/jma/cmip5/</a> </div><div><br></div><div>Start by reading the README file. There may be much more there than you need, but you can see how I generate the PDEF file and the GrADS descriptor files automatically with the grads script write_ctl.gs. Also, I interpolate to a linear 0.5-degree grid, which may not meet your needs.</div><div>--Jennifer</div><div><br></div><div><br></div><div><div><div><div><div><div>On May 16, 2013, at 4:13 PM, Fernanda Casagrande wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div class="hmmessage" style="font-size: 12pt; font-family: Calibri; "><div dir="ltr"><br>Hello,<span class="Apple-converted-space"> </span><br><br><br><span id="result_box" class="short_text"><span title="Como eu posso usar uma grade tripolar no grads ?" style="background-color: rgb(255, 255, 255); ">How can I use a tripolar grid in grads?<span class="Apple-converted-space"> </span><br><br>or<span class="Apple-converted-space"> </span><br><br></span></span>Can we regrid tripolar grid data from GFDL MOM model outputs (NetCDF format) to regular grid using grads?<br><br><br>Best Regards.<span class="Apple-converted-space"> </span><br><br>Fernanda<span class="Apple-converted-space"> </span><br><br></div>_______________________________________________<br>gradsusr mailing list<br><a href="mailto:gradsusr@gradsusr.org">gradsusr@gradsusr.org</a><br><a href="http://gradsusr.org/mailman/listinfo/gradsusr">http://gradsusr.org/mailman/listinfo/gradsusr</a><br></div></span></blockquote></div><br><div apple-content-edited="true">
<span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>--</div><div>Jennifer M. Adams</div><div>IGES/COLA</div><div>4041 Powder Mill Road, Suite 302</div><div>Calverton, MD 20705</div><div><a href="mailto:jma@cola.iges.org">jma@cola.iges.org</a></div><div><br class="khtml-block-placeholder"></div><br class="Apple-interchange-newline"></span></span></span>
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