how to run l2gen for PRISM?

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oo_processing
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how to run l2gen for PRISM?

by oo_processing » Tue Jan 30, 2024 10:09 am America/New_York

Dear Support,

My purpose is to derive Rrs from PRISM L1B files. I made a simple try with this file https://oceandata.sci.gsfc.nasa.gov/getfile/PRM2017147131440.L1B.nc, but no luck.
#######################
$ l2gen ifile='PRM2017147131440.L1B.nc' l2prod='Rrs_vvv' ofile='test.L2.nc'
Loading default parameters from /shares/cms_optics/apps/seadas/ocssw/V2023.2/share/common/msl12_defaults.par
Input file PRM2017147131440.L1B.nc is a NetCDF4 PRISM L2 file.

Loading characteristics for (null)
Segmentation fault (core dumped)
#######################

Please advise, thanks!
Yuyuan

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OB SeaDAS - xuanyang02
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Re: how to run l2gen for PRISM?

by OB SeaDAS - xuanyang02 » Tue Jan 30, 2024 12:42 pm America/New_York

"Input file PRM2017147131440.L1B.nc is a NetCDF4 PRISM L2 file" indicates that l2gen thinks that PRM2017147131440.L1B.nc is a NetCDF4 PRISM L2 file

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Re: how to run l2gen for PRISM?

by oo_processing » Tue Jan 30, 2024 1:35 pm America/New_York

OB SeaDAS - xuanyang02 wrote: Tue Jan 30, 2024 12:42 pm America/New_York "Input file PRM2017147131440.L1B.nc is a NetCDF4 PRISM L2 file" indicates that l2gen thinks that PRM2017147131440.L1B.nc is a NetCDF4 PRISM L2 file
You are right. But why did l2gen crash right after that? I tested l2gen command for aqua without any problem in my environment.
Thanks again
Yuyuan

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Re: how to run l2gen for PRISM?

by OB SeaDAS - xuanyang02 » Tue Jan 30, 2024 2:22 pm America/New_York

Maybe l2gen needs an L1 file instead of L2 file as input?

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Re: how to run l2gen for PRISM?

by oo_processing » Tue Jan 30, 2024 3:15 pm America/New_York

OB SeaDAS - xuanyang02 wrote: Tue Jan 30, 2024 2:22 pm America/New_York Maybe l2gen needs an L1 file instead of L2 file as input?
However, I got this file from nasa server, it's labelled as L1B, and it's placed under Level-1B folder.
https://oceandata.sci.gsfc.nasa.gov/getfile/PRM2017147131440.L1B.nc
https://oceandata.sci.gsfc.nasa.gov/directdataaccess/Level-1B/PRISM/2017/147/
If it's not, could you show me where I can get a L1 file of PRISM?

Yuyuan

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Re: how to run l2gen for PRISM?

by OB.DAAC - SeanBailey » Thu Feb 01, 2024 1:52 pm America/New_York

The answer is simple....l2gen supports (in the loosest sense) PRISM in ENVI format, not the special netCDF4 format created for the CORAL program. Though this did highlight the fact that the metadata in the L1B files is amiss...we'll look at correcting that :D

For context, support for the ENVI format PRISM data was include in l2gen so that PRISM could be used as a proxy format for the PACE OCI sensor (which launches in a little over 4 days and 11 hours as of this writing) before we had the ability to simulate the OCI instrument data (before, even the instrument design was finalized). We were subsequently asked to archive the CORAL mission data and requested that those data be in netCDF4 format. Never really thought about processing it to L2 with l2gen, since the CORAL project had it's own L2 processor and provided us with their L2 files...

It probably wouldn't be too hard to modify l2gen to support these CORAL PRISM netCDF4 files, but we have a lot on our plate these days (the aforementioned PACE launch ...)

Sean

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