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modis processing error in Seadas 8.1

Posted: Mon Jan 24, 2022 9:44 am America/New_York
by junzhao
Hi there,

Just tried to process MODIS data using SeaDAS 8.1. But ran into some errors.

I was using Ubuntu 18. All codes worked well when the resolution was set to 1000 m. My ROI is 21.3-22.1 N, 111.5-112.9 E. But if the resolution was set to 250 m. The output geographic coverage was wrong. Please see the coverage attached below:

:northernmost_latitude = 14.45956f ;
:southernmost_latitude = 14.04914f ;
:easternmost_longitude = 125.6533f ;
:westernmost_longitude = 125.3024f ;

Any suggestions would be greatly appreciated.

Jun

Re: modis processing error in Seadas 8.1

Posted: Wed Jan 26, 2022 10:16 am America/New_York
by OB SeaDAS - xuanyang02
Is your OCSSW V2021.2?

Can you share the filename of your modis L1B file, so we can reproduce the error?

Re: modis processing error in Seadas 8.1

Posted: Wed Jan 26, 2022 11:07 am America/New_York
by OB.DAAC - SeanBailey
When you respond to Bing's request, please also include the command-line options (or parameter file) used.

If you were using the north/south/east/west geographic extract options in l2gen, one thing to try is to extract the L1A file to your region of interest, generate a geolocation file for that extracted L1A file, generate the corresponding L1B file and process that extracted L1B/GEO data with l2gen, setting the resolution to 250m but NOT setting the north/south/east/west (or spixl/epixl/sline/eline) options.

Regards,
Sean

Re: modis processing error in Seadas 8.1

Posted: Fri Jan 28, 2022 12:47 am America/New_York
by junzhao
OB SeaDAS - xuanyang02 wrote: Wed Jan 26, 2022 10:16 am America/New_York Is your OCSSW V2021.2?

Can you share the filename of your modis L1B file, so we can reproduce the error?
The L1B file name is A2014329052000.L1B_LAC. I installed the most recent version of OCSSW, V2022.0.

The par file used is attached below:

ifile=/tmp/T2014329035000.L1B_LAC
geofile=/tmp/TERRA_MODIS.20141125T035000.GEO.hdf
ofile=/tmp/result/T2014329035000.L2_LAC.nc
resolution=250
north=22.3
south=21.1
west=111.3
east=113.1
oformat=netcdf4
l2prod=Rrs_nnn,rhos_nnn,sst,l2_flags,chlor_a,nflh,aph_443_qaa
aer_opt=-2
aer_wave_short=1240
aer_wave_long=2130
aer_swir_short=1240
aer_swir_long=2130
cloud_thresh=0.018
cloud_wave=2130
maskcloud=1
icefile=/opt/seadas_8.1/ocssw/var/anc/2014/329/N2014329_SST_OIV2AV_24h.nc
met1=/opt/seadas_8.1/ocssw/var/anc/2014/329/N201432900_MET_NCEPR2_6h.hdf
met2=/opt/seadas_8.1/ocssw/var/anc/2014/329/N201432906_MET_NCEPR2_6h.hdf
met3=/opt/seadas_8.1/ocssw/var/anc/2014/329/N201432906_MET_NCEPR2_6h.hdf
ozone1=/opt/seadas_8.1/ocssw/var/anc/2014/329/N201432900_O3_AURAOMI_24h.hdf
ozone2=/opt/seadas_8.1/ocssw/var/anc/2014/330/N201433000_O3_AURAOMI_24h.hdf
ozone3=/opt/seadas_8.1/ocssw/var/anc/2014/330/N201433000_O3_AURAOMI_24h.hdf
sstfile=/opt/seadas_8.1/ocssw/var/anc/2014/329/N2014329_SST_OIV2AV_24h.nc
OB.DAAC - SeanBailey wrote: Wed Jan 26, 2022 11:07 am America/New_York When you respond to Bing's request, please also include the command-line options (or parameter file) used.

If you were using the north/south/east/west geographic extract options in l2gen, one thing to try is to extract the L1A file to your region of interest, generate a geolocation file for that extracted L1A file, generate the corresponding L1B file and process that extracted L1B/GEO data with l2gen, setting the resolution to 250m but NOT setting the north/south/east/west (or spixl/epixl/sline/eline) options.

Regards,
Sean
Thank you for your reply, Sean. I will try the solution your suggested.

Jun