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<p style="margin: 0in 0in 12pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">Using NCL version 6.2.1, I am trying to use ESMF_regrid to interpolate data from a regular
lat/lon (0.1 x 0.1 degree) grid to an unstructured MPAS grid. I am working off of the ESMF_rect_to_unstruct.ncl template.</span></p>
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<p style="margin: 0in 0in 12pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">I am providing the DstGridLat and DstGridLon values from an existing MPAS input file. This
MPAS mesh has nCells = 163842 cells and I am passing the double latCell(nCells) and double lonCell(nCells) variables to DstGridLat and DstGridLon.</span></p>
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<p style="margin: 0in 0in 12pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">Once the script starts processing the destination grid, the following screen output appears:</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">(0)<span style="mso-tab-count: 1;">
</span>get_dst_grid_info: destination lat dims = (163842)</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">(0)<span style="mso-tab-count: 1;">
</span>get_dst_grid_info: destination lon dims = (163842)</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">(0)<span style="mso-tab-count: 1;">
</span>unstructured_to_ESMF: triangulating the data ... this can be slow</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">(0)<span style="mso-tab-count: 1;">
</span>min/max ElementVertices = 0/163841</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">(0)<span style="mso-tab-count: 1;">
</span>unstructured_to_ESMF: total number of elements created: 327680</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";"> </span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">After that, the weights are being generated and the input data is interpolated . However,
the dimension of that interpolated output is 327680 (i.e. the number of “elements”), not 163842 (i.e. the number of destination lat/lon points specified). When I write out the interpolated data, it has 327680 values. That number of
<span style="mso-spacerun: yes;"> </span>“elements” matches the number of “Vertices” in my existing MPAS input file from which the DstGridLat and DstGridLon values were pulled.</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";"> </span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">I am sure I am missing something very basic, but I am stuck figuring out why the interpolated
data has more elements than I am expecting.</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";"> </span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">I am attaching the script, screen output, header of the destination lat/lon grid description
file provided to the script, and the headers of the SrcFileName, DstFileName, and ncf file containing the interpolated data that are created by the script.</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";"> </span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">I have also uploaded the files required to run the script (i.e. the
<span>edgar_HTAP_NOx_emi_TRANSPORT_2010.0.1x0.1.nc</span> file containing the data to be interpolated and the existing MPAS input file
<span>static.90-25.usgs.nc</span> containing the DstGridLat and DstGridLon values) to the anonymous ftp server.</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";"> </span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">Thank you very much for your help,</span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";"> </span></p>
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<p style="margin: 0in 0in 0pt; line-height: normal;"><span style="font-family: "Times New Roman","serif"; font-size: 10pt; mso-fareast-font-family: "Times New Roman";">Christian</span></p>
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