processing an L1A file downloaded from modaps with l2gen

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alaroy
Posts: 57
Joined: Tue Nov 21, 2006 3:33 pm America/New_York

processing an L1A file downloaded from modaps with l2gen

by alaroy » Thu Jan 18, 2018 6:27 pm America/New_York

Hi folks!

I'm trying to convert an MODIS L1A file I retrieved from modaps (specifically ftp://nrt3.modaps.eosdis.nasa.gov/allData/61/MOD01/2018/018/MOD01.A2018018.2025.061.NRT.hdf) to L2, however when I try it I get the following error:

dolphin]$ export OCDATAROOT=/local-working/seadas-7.4/ocssw/run/data/
dolphin]$ l2gen ifile=MOD01.A2018018.2025.061.NRT.hdf
-E- /data5/swdev/seadas/build/src/l2gen/getformat.c Line 485: Unrecognized HDF-EOS file /home/alaroy/Downloads/MOD01.A2018018.2025.061.NRT.hdf
-E- /data5/swdev/seadas/build/src/l2gen/msl12_input.c Line 1450: Could not find type for file /home/alaroy/Downloads/MOD01.A2018018.2025.061.NRT.hdf.
-E- /data5/swdev/seadas/build/src/l2gen/msl12_input.c: Error reading program options.
-E- ./l2gen: Error parsing input parameters.

I specifically want to process L1A files from modaps in order to have an additional data path available in case the primary path fails. Is there some l2gen command line option that I'm missing that supports processing this data? If not is there a format converter out there somewhere that will turn a file in the MODAPS format into one supported by l2gen?

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OB.DAAC - SeanBailey
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processing an L1A file downloaded from modaps with l2gen

by OB.DAAC - SeanBailey » Thu Jan 18, 2018 8:38 pm America/New_York

You need to pass l2gen a MODIS L1B file and geolocation file. 

Run modis_GEO.py <L1A file> followed by modis_L1B.py <L1A file> to get the L1B and GEO required for l2gen.

Sean

spectral_uvic1
Posts: 1
Joined: Thu Feb 13, 2020 4:14 pm America/New_York

processing an L1A file downloaded from modaps with l2gen

by spectral_uvic1 » Thu Feb 13, 2020 4:46 pm America/New_York

Dear SeaDAS supporting team
I have a script (used to work) to process MODIS Aqua L1A to L1B and L1B to L2SWIR.
Now I am getting these errors:

We failed to reach a server.
Please retry this request at a later time.
URL attempted: oceandata.sci.gsfc.nasa.gov
HTTP Error: 302 - Found
*** ERROR: The HTTP transfer failed with status code 302.
*** Please check your network connection and for the existence of the remote file:
*** oceandata.sci.gsfc.nasa.gov/cgi/getfile/PM1EPHND.P2019060.1200.003
***
*** Also check to make sure you have write permissions under the directory:
*** /home/spectral/seadas-7.4/ocssw/run/var/anc/2019/060

Cannot create geolocation from A2019060203500.L1A_LAC.x.hdf; exiting.
GEO file created
ERROR: File A2019060203500.GEO.x.hdf does not exist.
L1B_LAC file created
-E- /data5/swdev/seadas/build/src/l2gen/getformat.c: Input file 'A2019060203500.L1B_LAC.x.hdf' does not exist or cannot open.
-E- /data5/swdev/seadas/build/src/l2gen/msl12_input.c Line 1450: Could not find type for file A2019060203500.L1B_LAC.x.hdf.
-E- /data5/swdev/seadas/build/src/l2gen/msl12_input.c: Error reading program options.
-E- l2gen: Error parsing input parameters.
l2gen SWIR file created

I have checked the network connection
oceandata.sci.gsfc.nasa.gov/cgi/getfile/PM1EPHND.P2019060.1200.003
And I can download this file

I also checked to make sure I have write permissions under the directory:
/home/spectral/seadas-7.4/ocssw/run/var/anc/2019/060

And Yes, I do have permission

Any help would be appreciated

Maycira

gnwiii
Posts: 606
Joined: Fri Jan 29, 2021 5:51 pm America/New_York
Answers: 1

processing an L1A file downloaded from modaps with l2gen

by gnwiii » Thu Feb 13, 2020 5:10 pm America/New_York

I assume your script uses the OCSSW Python scripts.   These scripts were updated recently, so if you have not recently updated, you need to update the OCSSW software either using the SeaDAS 7 GUI or with install_ocssw.py.

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