Rrc for Floating Algae Index

Good afternoon, I am new to the atmospheric correction, I would like to know how the atmospheric correction is made, including the rayleigh correction, to obtain the floating algae index.
Somebody help me?

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Please give some more details: What data are you using, what tools did you try, what issues did you encounter?
It is hard to help without knowing your exact problem.

Hi, I’m currently using Sentinel 2, but in the future I want to use GOES, I’m trying to process in SNAP. What I am trying to do is automate the calculation of the FAI index in a pipeline.
FAI = RrcNIR- R’rcNIR
R’rcNIR = RrcRED + RrcSWIR - RrcRED× (λNIR - λRED)/(λSWIR - λRED)

where R’rcNIR is the baseline reflectance in the NIR band derived from a linear interpolation between the red and SWIR bands.

FAI.pdf (1.1 MB)

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it’s possible to download the L2A, which are sentinel 2 already Atmospheric Corrected granular, if it’s not available, and the only S2 are S2-L1C, in this case you could apply sen2cor to AC, the image.
All the indices are already available under Optical tab, Thematic land processing, and Thematic water processing, I’m not sure if this index is available under different name in SNAP, but FAI is not.

In this case of FAI, it’s possible to use bandmath to calculate it.

You can read about the AC in the software user manual which is linked on the page:
http://step.esa.int/main/third-party-plugins-2/sen2cor/sen2cor_v2-8/