Hi John,<div><br></div><div>    Something tells me that you might know this. I have these CMAQ netcdf files from the DISCOVER-AQ campaign (see ncdump below). Do you happen to know the PDEF line that goes with these? I have the grid metrics in a separate file, I could always write some code to remap these, but if grads can do it on the fly it would be good enough for the exploratory data analysis that I need to perform.</div>
<div><br></div><div>   Thanks,</div><div><br></div><div>       Arlindo</div><div><br></div><div>-----</div><div><br></div><div><div>netcdf UMA_AOD {</div><div>dimensions:</div><div><span class="Apple-tab-span" style="white-space:pre">        </span>TSTEP = UNLIMITED ; // (48 currently)</div>
<div><span class="Apple-tab-span" style="white-space:pre">        </span>DATE-TIME = 2 ;</div><div><span class="Apple-tab-span" style="white-space:pre">        </span>LAY = 1 ;</div><div><span class="Apple-tab-span" style="white-space:pre">        </span>VAR = 1 ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">        </span>ROW = 79 ;</div><div><span class="Apple-tab-span" style="white-space:pre">        </span>COL = 112 ;</div><div>variables:</div><div><span class="Apple-tab-span" style="white-space:pre">        </span>int TFLAG(TSTEP, VAR, DATE-TIME) ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>TFLAG:units = &quot;&lt;YYYYDDD,HHMMSS&gt;&quot; ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>TFLAG:long_name = &quot;TFLAG           &quot; ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>TFLAG:var_desc = &quot;Timestep-valid flags:  (1) YYYYDDD or (2) HHMMSS                                &quot; ;</div><div><span class="Apple-tab-span" style="white-space:pre">        </span>float AOD(TSTEP, LAY, ROW, COL) ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>AOD:long_name = &quot;AOD             &quot; ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>AOD:units = &quot;unitless        &quot; ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>AOD:var_desc = &quot;AOD by Mie in VIS file                                                          &quot; ;</div><div><br></div><div>// global attributes:</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:IOAPI_VERSION = &quot;$Id: @(#) ioapi library version 3.0 $                                           &quot; ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:EXEC_ID = &quot;????????????????                                                                &quot; ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:FTYPE = 1 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:CDATE = 2011182 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:CTIME = 164809 ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:WDATE = 2011182 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:WTIME = 164809 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:SDATE = 2011182 ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:STIME = 130000 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:TSTEP = 10000 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:NTHIK = 1 ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:NCOLS = 112 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:NROWS = 79 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:NLAYS = 1 ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:NVARS = 1 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:GDTYP = 2 ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:P_ALP = 33. ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:P_BET = 45. ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:P_GAM = -97. ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:XCENT = -97. ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:YCENT = 40. ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:XORIG = 984000. ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:YORIG = -384000. ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:XCELL = 12000. ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:YCELL = 12000. ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:VGTYP = 1 ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:VGTOP = 200.f ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:VGLVLS = 1.f, 0.9959855f ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:GDNAM = &quot;AQF_CONUS_5x    &quot; ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:UPNAM = &quot;setup           &quot; ;</div><div><span class="Apple-tab-span" style="white-space:pre">                </span>:VAR-LIST = &quot;AOD             &quot; ;</div>
<div><span class="Apple-tab-span" style="white-space:pre">                </span>:FILEDESC = &quot;hourly 1-layer cross-point Visibility Information                                                                                             </div>
<div><br></div>-- <br>Arlindo da Silva<br><a href="mailto:dasilva@alum.mit.edu">dasilva@alum.mit.edu</a><br>
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