MODIS GEO file

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gnwiii
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MODIS GEO file

by gnwiii » Wed Feb 03, 2021 6:51 am America/New_York

The NetCDF4-CF metadata provides many of the details for the level-2 processing.  You can view the metadata using "ncdump -h" in a terminal or using a SeaDAS or SNAP GUI, NASA Panoply, or many other programs.

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OB.DAAC - SeanBailey
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MODIS GEO file

by OB.DAAC - SeanBailey » Wed Feb 03, 2021 8:24 am America/New_York

When we process the data in our operational environment, we're using a parameter file so as to not have to put all the runtime parameters on the command line.  That's what the ".param" file is.
What is likely different between your processing and ours is the use of the ancillary data.  We defined them (in the .param file), but you did not so l2gen used climatologies for those inputs.
Use the getanc.py script to retrieve the ancillary data (the script will also generate a .anc file that is analogous to the .param file, containing the ancillary parameters needed).

You can verify the inputs by doing as George said and using ncdump -h to see exactly how the file was generated.  The processing_control group contains an input_parameters group with every single input parameter used.  MOST are defaults and need not be passed in, but some, like the met#, ozone#, sstfile, etc. are specific to the file being processed and need to be provided by the calling process.

Regards,
Sean

maheshgeotech38
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MODIS GEO file

by maheshgeotech38 » Thu Feb 04, 2021 10:20 am America/New_York

Dear Sir,
              Thank your support, Please support me solve the below problem.

(base) umamahesh@uma:/mnt/d/Ubuntu/MODIS-A$ l2gen ifile=A2012062073500.L1B_LAC geofile=A2012062073500.GEO ofile=A2012062073500.L2 l2prod=chlor_a par=A2012062073500.L1B_LAC.anc north=17.518 west=81.297 south=16.614 east=84.434
Input file A2012062073500.L1B_LAC is MODIS Aqua Level-1B HDF-EOS product.
Loading default parameters from /home/umamahesh/ocssw/share/common/msl12_defaults.par
Loading default parameters for MODISA from /home/umamahesh/ocssw/share/modis/msl12_defaults.par
Loading default sub-sensor parameters for MODISA from /home/umamahesh/ocssw/share/modis/aqua/msl12_defaults.par
Loading parameters for suite OC from /home/umamahesh/ocssw/share/modis/msl12_defaults_OC.par
Loading command line parameters

Loading user parameters for MODISA

Loading characteristics for MODISA
Opening sensor information file /home/umamahesh/ocssw/share/modis/aqua/msl12_sensor_info.dat
  Bnd   Lam       Fo    Tau_r     k_oz    k_no2    t_co2   awhite       aw      bbw
    0  412.000  172.912 3.099e-01 1.987e-03 5.814e-19 1.000e+00 1.000e+00 2.030e-02 2.884e-03
    1  443.000  187.622 2.367e-01 3.189e-03 4.985e-19 1.000e+00 1.000e+00 1.110e-02 2.181e-03
    2  469.000  205.878 1.914e-01 8.745e-03 3.938e-19 1.000e+00 1.000e+00 1.034e-02 1.749e-03
    3  488.000  194.933 1.592e-01 2.032e-02 2.878e-19 1.000e+00 1.000e+00 1.676e-02 1.447e-03
    4  531.000  185.747 1.126e-01 6.838e-02 1.525e-19 1.000e+00 1.000e+00 4.494e-02 1.014e-03
    5  547.000  186.539 9.906e-02 8.622e-02 1.194e-19 1.000e+00 1.000e+00 5.491e-02 8.886e-04
    6  555.000  183.869 9.432e-02 9.553e-02 9.445e-20 1.000e+00 1.000e+00 5.839e-02 8.443e-04
    7  645.000  157.811 5.082e-02 7.382e-02 1.382e-20 1.000e+00 9.133e-01 3.458e-01 4.469e-04
    8  667.000  152.255 4.443e-02 4.890e-02 7.065e-21 1.000e+00 8.921e-01 4.923e-01 3.900e-04
    9  678.000  148.052 4.146e-02 3.787e-02 8.304e-21 1.000e+00 8.783e-01 5.116e-01 3.634e-04
   10  748.000  128.065 2.849e-02 1.235e-02 2.157e-21 1.000e+00 7.832e-01 2.800e+00 2.470e-04
   11  859.000   97.174 1.613e-02 2.347e-03 6.212e-23 1.000e+00 6.519e-01 4.396e+00 1.384e-04
   12  869.000   95.824 1.540e-02 1.936e-03 7.872e-23 1.000e+00 6.403e-01 4.727e+00 1.320e-04
   13 1240.000   45.467 3.617e-03 0.000e+00 0.000e+00 9.994e-01 0.000e+00 1.147e+02 3.021e-05
   14 1640.000   23.977 1.219e-03 0.000e+00 0.000e+00 9.890e-01 0.000e+00 6.689e+02 1.000e-05
   15 2130.000    9.885 4.286e-04 0.000e+00 0.000e+00 9.696e-01 0.000e+00 2.810e+03 3.465e-06

  Bnd   Lam
   16 3750.000
   17 3959.000
   18 4050.000
   19 6715.000
   20 7325.000
   21 8550.000
   22 11000.000
   23 12000.000

Internal data compression requested at compression level: 4
Opening filter file /home/umamahesh/ocssw/share/modis/msl12_filter.dat
Setting 7 x 5 straylight filter on HILT mask

Filter Kernel
1 1 1 1 1 1 1
1 1 1 1 1 1 1
1 1 1 1 1 1 1
1 1 1 1 1 1 1
1 1 1 1 1 1 1

Minimum fill set to 1 pixels

Setting 7 x 5 straylight filter on CLDICE mask

Filter Kernel
1 1 1 1 1 1 1
1 1 1 1 1 1 1
1 1 1 1 1 1 1
1 1 1 1 1 1 1
1 1 1 1 1 1 1

Minimum fill set to 1 pixels

Processing at 1000 meter resolution.
    1000-meter file: A2012062073500.L1B_LAC

Allocated 2365502 bytes in L1 record.
Allocated 920720 bytes in L2 record.

Opening: A2012062073500.L2

The following products will be included in A2012062073500.L2.
0 chlor_a
1 l2_flags

Begin l2gen Version 9.5.0-V2019.3 Processing
Sensor is MODISA
Sensor ID is 7
Sensor has 16 reflective bands
Sensor has 8 emissive bands
Number of along-track detectors per band is 10
Number of input pixels per scan is 1354
Processing pixels 918 to 1160 by 1
Processing scans 1018 to 1172 by 1
Ocean processing enabled
Land processing enabled
Atmospheric correction enabled

Begin MSl12 processing at 2021035202858000

Allocated 2365502 bytes in L1 record.
Allocated 2365502 bytes in L1 record.
Allocated 2365502 bytes in L1 record.
Allocated 2365502 bytes in L1 record.
Allocated 2365502 bytes in L1 record.
Loading radiance to brightness temperature from /home/umamahesh/ocssw/share/modis/aqua/cal/bt_modisa.hdf
Loading land mask file from /home/umamahesh/ocssw/share/common/landmask_GMT15ARC.nc
Loading bathymetry mask file from /home/umamahesh/ocssw/share/common/watermask.dat
Loading ice mask file from /home/mohammed_suhail/SeaDAS/OCSSW/var/anc/2012/061/N201206100_SEAICE_NSIDC_24h.hdf
-E- /home/seadas/ocssw/src/l2gen/ice_mask.c line 223: File, "/home/mohammed_suhail/SeaDAS/OCSSW/var/anc/2012/061/N201206100_SEAICE_NSIDC_24h.hdf", doesn't follow naming convention described at http://nsidc.org/data/docs/daac/nsidc0051_gsfc_seaice.gd.html#namingconvention .
-E- /home/seadas/ocssw/src/l2gen/loadl1.c : Unable to initialize ice mask

OB.DAAC - SeanBailey
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MODIS GEO file

by OB.DAAC - SeanBailey » Thu Feb 04, 2021 4:13 pm America/New_York

make sure the N201206100_SEAICE_NSIDC_24h.hdf is a vaild HDF4 file.  The Linux command "file" should show:

$ file N201206100_SEAICE_NSIDC_24h.hdf
N201206100_SEAICE_NSIDC_24h.hdf: Hierarchical Data Format (version 4) data


Sean

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