MODIS-Aqua POC data June 2014 onwards

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MODIS-Aqua POC data June 2014 onwards

by peter.strutton » Tue Aug 22, 2017 4:01 pm America/New_York

There seems to be a problem with the monthly 9km POC data after May 2014, has anyone else noticed this? File sizes become much smaller and seem corrupted?


OB SeaDAS - dshea
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MODIS-Aqua POC data June 2014 onwards

by OB SeaDAS - dshea » Wed Aug 23, 2017 9:59 am America/New_York

The SMI files after May 2014 are produced by l3mapgen instead of smigen.  The new files are smaller since the poc data is stored as a scaled 16 bit int instead of a 32 bit float.  As you noticed, the file size is almost 3 times smaller.  From the NetCDF metadata:

  short poc(lat, lon) ;
    poc:scale_factor = 0.2f ;
    poc:add_offset = 6400.f ;
    poc:_FillValue = -32767s ;

pocVal(float) = poc(short) * scale_factor + add_offset

The files look fine.  Can you point me to a file that seems corrupt?


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