Processing level 0 MODIS Aqua Product- nlw bands

[fatemahfa]

Good Evening all;
I am using MODIS Aqua images for ocean studies purposes. I used MODIS level 0 image and processed it to MODIS Level 2 image and in the l2gen command I selected all the bands. However the output does not show bands above 678 wave length and I want the band at nlw 748 to calculate modified flousoscence hight. Could you please guide me on that?
Kind Regards

[OB SeaDAS - xuanyang02]

1) In l2gen GUI, click "Products*" tab, and check the box next to nLw in the "Product Selector" section

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2) In l2gen GUI, click the "Main" tab. In the "Parfile" section, click the "Save Parameters" button and save the file as l2gen-tmpParFile-nlw.par in the directory where your data is, in my case ~/Scenes/MODIS_AQUA/run

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3) On the command line

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cd ~/Scenes/MODIS_AQUA/run (your data directory)
vi l2gen-tmpParFile-nlw.par

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[OB SeaDAS - xuanyang02]

4) insert "nLw_748" into the "l2prod= " line

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5) save and quit vi

6)

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l2gen par=l2gen-tmpParFile-nlw.par

[fatemahfa]

Thank you a lot for the detailed explanation
could you please guide me how to write nlw_748 in the command line because I didn't know how to modify it.

[fatemahfa]

And how do I type the last command also
Thank you for your time

[OB SeaDAS - xuanyang02]

In vi, you use "i" to insert text. Here is some help with vi: https://www.guru99.com/the-vi-editor.html#3

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/home/user/ocssw/bin/l2gen par=l2gen-tmpParFile-nlw.par

I assume you have ocssw installed under /home/user, judging from a previous post

[fatemahfa]

Thank you a lot the link was really helpful.
I was searching for the l2gen_par in the OCSSW but showing no such file or directory.
Do you know why?
kind regards

[OB SeaDAS - xuanyang02]

There is a space between l2gen and par.

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/home/user/ocssw/bin/l2gen par=l2gen-tmpParFile-nlw.par

We are trying to run the command l2gen with the par file "l2gen-tmpParFile-nlw.par", not l2gen_par.
Since l2gen was not recognized, I was suggesting you relpace "l2gen" with "/home/user/ocssw/bin/l2gen".

In your OCSW-L2GEN.pdf, I saw part of the errors on your terminal containing "is not defined", "12_input.c: Error reading program option", "or parsing input parameters". Can you copy that error and paste here?

BTW, when you attach an image, please choose "Place inline" so we can see the image without downloading your pdf file.

[fatemahfa]

Thank you for your reply
I tried to run it again and here is the error:
user@user-OptiPlex-9020:~/Desktop/23-12-2008$ /home/user/ocssw/bin/l2gen par=l2gen-tmpParFile-nlw.par
-E- OCDATAROOT environment variable is not defined.
-E- /home/seadas/ocssw/src/l2gen/msl12_input.c: Error reading program options.
-E- /home/user/ocssw/bin/l2gen: Error parsing input parameters.

[gnwiii]

Thank you a lot the link was really helpful.
I was searching for the l2gen_par in the OCSSW but showing no such file or directory.
Do you know why?
kind regards

It looks like you are struggling with the linux command line. Rather than using the forum for step-by-step command-line help, you will find it better in the long run to spend some time with a good command-line tutorial or online course. The SeaDAS GUI is very useful, but when things aren't working, linux command line tools are often needed. Many applications require running similar calculations on many files, Linux command-line tools are much faster for such tasks than running the jobs one-by-one in the GUI. Often the best way to get help from online forums is to paste text from a terminal in your post. This makes it easier for people to quote sections of your post and also makes it possible for others with the same issue to find your posts.

A good place to start is <https://linuxcommand.org>. Linux users are generally eager to help new users get started. Look for a linux user group in your area and ask about online resources and tutorials.