SeaWiFS azimuth angles in Level2

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Joined: Thu Sep 14, 2006 3:56 am America/New_York

SeaWiFS azimuth angles in Level2

by fsteinmetz » Fri Jun 01, 2018 8:27 am America/New_York

There seems to be a formatting issue for azimuth angles in Level2 SeaWiFS (when including sola and sena in output).
SeaWiFS azimuth angles are defined in [0, 360], but netCDF attributes actually define :
<class 'netCDF4._netCDF4.Variable'>
int16 sola(number_of_lines, pixels_per_line)
    long_name: Solar Azimuth Angle
    scale_factor: 0.0111111
    add_offset: 0.0
    units: degree
    standard_name: solar_azimuth_angle
    _FillValue: -32767
    valid_min: -16200
    valid_max: 16200
path = /geophysical_data
unlimited dimensions:
current shape = (3930, 248)
filling on

...which corresponds to a valid range of [-180, 180].
Thus when reading these angles with typical netCDF readers, the values greater than 180 are masked.
A workaround can be to apply set_auto_mask(False) to those datasets. But fixing this formatting would certainly be welcome.
This does not apply to MODIS and VIIRS because their azimuth angles are defined in [-180, 180].
Note: this is with l2gen 8.10.3-r0


OB SeaDAS - dshea
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Posts: 225
Joined: Thu Mar 05, 2009 10:25 am America/New_York

SeaWiFS azimuth angles in Level2

by OB SeaDAS - dshea » Wed Jun 06, 2018 9:16 am America/New_York

I'll look at this and decide how we want to fix it.

Thanks for pointing it out.


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