seadas l2gen

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ynrs
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seadas l2gen

by ynrs » Tue Jun 25, 2024 6:04 am America/New_York

I am using SeaDAS l2gen to perform atmospheric correction to TERRA/MODIS images. When I select the default parameters, Some grid points in the lake area has no values (white color the image). My study area is a shallow inland lake and a turbid water body with severe eutrophication.
I think it may be necessary to adjust the parameters for running l2gen. Firstly, what are the differences between the options in the aer_opt item under # PROCESSING OPTIONS? Additionally, under # THRESHOLDS, what do aotthreshold, chlthreshold, cirrus_thresh, cloud_eps, cloud_thresh, etc. mean respectively? What are the principles for setting them?
I would appreciate your help.
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OB SeaDAS - knowles
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Re: seadas l2gen

by OB SeaDAS - knowles » Tue Jun 25, 2024 1:19 pm America/New_York

The missing coastal data pixels are likely compromised quality due to detected/suspected presence of aerosols.

You could try using different aerosol models which are governed by aer_opt. For an example see:
https://www.youtube.com/watch?v=oGwupIMKvdw&t=5422s

Danny

ynrs
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Joined: Sun Mar 12, 2023 11:34 pm America/New_York
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Re: seadas l2gen

by ynrs » Wed Jun 26, 2024 9:37 am America/New_York

Thank you for sharing the video, but I'm still a bit confused. Should I run all the options, compare all the results, and then select the best model based on experience?Additionally, the video does not explain how to set the threshold. Could you provide information on this? Once again, thank you very much.

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