Atmospheric Correction in HICO

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vimal459
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Atmospheric Correction in HICO

by vimal459 » Thu Mar 22, 2018 3:16 am America/New_York

Hi,
In seadas7.4, I want know the atmospheric correction method such as Aerosol, Cloud, Rayleigh, Glint, and etc used for HICO processing. And where i can find the algorithm of mentioned atmospheric correction used in seadas?

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OB.DAAC - SeanBailey
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Atmospheric Correction in HICO

by OB.DAAC - SeanBailey » Thu Mar 22, 2018 10:54 am America/New_York

See: https://oceancolor.gsfc.nasa.gov/atbd/rrs/ and references therein

Sean

vimal459
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Atmospheric Correction in HICO

by vimal459 » Sun Mar 25, 2018 3:51 am America/New_York

Thank you  SeanBailey, I would like to learn how the algorithm are implemented in Seadas. I'm facing difficulties while trying to understand the atmocor1, atmocor2, rayleigh phase function, and etc. is there any technical document available ? and which algorithm implemented in seadas for rayleigh (rayleigh.c) ?

regards
Vimal

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Atmospheric Correction in HICO

by OB.DAAC - SeanBailey » Mon Mar 26, 2018 8:39 am America/New_York

Vimal,

The l2gen code is indeed quite complex.  It's not a simple "which algorithm is implemented" question, as that depends upon how the code was called.  It is highly configurable.
There is no technical document about the code, other than the code itself.

Sean

vimal459
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Atmospheric Correction in HICO

by vimal459 » Wed Mar 28, 2018 12:47 am America/New_York

Sean,
i'm trying to understand using the l2gen code. Particularly in Rayleigh part, mentioned Wang pressure correction, rest of the part i couldn't able to understand. it would be very helpful if you could provide something (algorithm implemented/paper ref) to understand.

Thanks & regards
Vimal

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Atmospheric Correction in HICO

by OB.DAAC - SeanBailey » Wed Mar 28, 2018 8:22 am America/New_York

As I see it, there are three ways to interpret your request.

1) Understanding the options available when running the l2gen binary.
For that, take a look at the associated  SeaDAS help page

2) Understanding the algorithms implemented within the l2gen code.
For that, the recently published document "Atmospheric Correction for Satellite Ocean Color Radiometry" and the associated Web Book on Atmospheric Correction are the most comprehensive references on the subject

3) Understanding the l2gen code itself.
Fire up a nice integrated development environment tool and load the ocssw source into it and prepare for a long night (... or month, or decade...), might want to grab a tall mug of coffee before you get started...

Sean

siggy_12
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Atmospheric Correction in HICO

by siggy_12 » Tue Apr 10, 2018 3:36 am America/New_York

I have installed seadas 7.4 and trying to install oc processors manually by installing all the repository from https://oceandata.gsfc.nasa.gov/ocssw. I have given the command:

user@user-Inspiron-3537:~$ ./install_ocssw.py --local=$HOME/seadas_downloads -b  v7.4
Installing bundles.sha256sum (1 of 7)
Installing common (2 of 7)
Not updating Git Repository, no-update requested
Installing OCSSW_bash.env (3 of 7)
cp: cannot stat ‘/home/suresh/seadas_downloads/OCSSW_bash.env.v7.4’: No such file or directory
Error - Executing command "cp /home/suresh/seadas_downloads/OCSSW_bash.env.v7.4 /home/suresh/ocssw"
Traceback (most recent call last):
  File "./install_ocssw.py", line 624, in <module>
    os.rename(os.path.join(installDir, 'OCSSW_bash.env.' + gitBranch), os.path.join(installDir, 'OCSSW_bash.env'))
OSError: [Errno 2] No such file or directory
suresh@suresh-Inspiron-3537:~$ ./install_ocssw.py --local=$HOME/seadas_downloads -b  v7.4
Installing bundles.sha256sum (1 of 7)
Installing common (2 of 7)
Not updating Git Repository, no-update requested
Installing OCSSW_bash.env (3 of 7)
Installing ocrvc (4 of 7)
Cloning into '/home/suresh/ocssw/run/data/ocrvc'...
Receiving objects: 100% (23/23), done.
Resolving deltas: 100% (7/7), done.
Checking connectivity... done.
Not updating Git Repository, no-update requested
Installing bin (5 of 7)
Cloning into '/home/suresh/ocssw/run/bin/linux_64'...
Receiving objects: 100% (1077/1077), 648.92 MiB | 29.60 MiB/s, done.
Resolving deltas: 100% (899/899), done.
Checking connectivity... done.
Not updating Git Repository, no-update requested
Installing bin3 (6 of 7)
Not updating Git Repository, no-update requested
Installing scripts (7 of 7)
Cloning into '/home/suresh/ocssw/run/scripts'...
Receiving objects: 100% (564/564), 276.10 KiB | 0 bytes/s, done.
Resolving deltas: 100% (409/409), done.
Checking connectivity... done.
Not updating Git Repository, no-update requested
Python version acceptable

After having installed everything manually. How do i get the dataprocessing option on my seadas.I want to process modis data

OB SeaDAS - knowles
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Atmospheric Correction in HICO

by OB SeaDAS - knowles » Tue Apr 10, 2018 9:18 am America/New_York

siggy_12

You should consider making new threads instead of posting new unrelated topics under existing threads.  By making your own thread, you can give the thread a name which directly relates to the question you are asking.  Not only will this help people notice and answer your post, but when your post is answered, it will help other users with the same questions find the answers.

In your seadas home directory {$SEADAS_HOME} edit the file $SEADAS_HOME/config/seadas.config

Find and set the following line to your ocssw root location:
seadas.ocssw.root = /home/suresh/ocssw

Danny

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Atmospheric Correction in HICO

by OB SeaDAS - dshea » Tue Apr 10, 2018 9:48 am America/New_York

Is there a reason you are not installing OCSSW using the GUI?

I just changed a few things in preparation for the SeaDAS 7.5 release.  You need to download the file:

https://oceandata.sci.gsfc.nasa.gov/ocssw/OCSSW_bash.env.v7.4
to:
/home/suresh/seadas_downloads

$ ./install_ocssw.py --local=$HOME/seadas_downloads -b  v7.4
(assuming OCSSWROOT is already set to  /home/suresh/ocssw)

Then you need to launch seadas
select menu OCSSW -> Install OCSSW Processors
set Local Install-dir to /home/suresh/ocssw
click the Run button

don

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