Difference between Rhos and Rrc ?

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Difference between Rhos and Rrc ?

Hello,

I wonder if there is a difference in what SeaDAS produces as Rhos and Rrc, the Rayleigh corrected reflectance used for FAI/AFAI algorithms.
Can you tell me the formula for both products (if they are different ?)
I would expect :
Rhos = pi * (Lt - Lr) / F0 * mu0, but I am not 100% certain.

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jared
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Difference between Rhos and Rrc ?

Hello,
rhos in SeaDAS is calculated from:  pi / F0 / mu0* (Lt/tg_sen/tg_sol - Lr)/tsol/tsen.
I don't think there is a Rrc product from SeaDAS. For FAI, Rrc= pi / F0 / mu0* (Lt/tg_sen/tg_sol - Lr).

Minwei

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Difference between Rhos and Rrc ?

Hello Minwei thank you,
Sad we can't write proper equations, could you write it with one single fraction please ? It is a bit hard to understand the way you wrote it.

Is it :
( pi * ((Lt / (tg_sen * tg_sen)) - Lr)) / ( F0 * mu0 * tsol * tsen ) ?

Sean wrote, https://oceancolor.gsfc.nasa.gov/forum/oceancolor/topic_show.pl?tid=2229 :
rhos = PI / F0 / mu0  * (Lt / tg_sol / tg_sen - Lr)  / t_sol / t_sen / t_o2 / t_h2o

Has the / t_o2 / t_h2o been removed since ?
Regards

jared
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Difference between Rhos and Rrc ?

sorry for the confusion. It is ( pi * ((Lt / (tg_sen * tg_sen)) - Lr)) / ( F0 * mu0 * tsol * tsen ).
The / t_o2 / t_h2o is not removed. I don't know the reason for the division of t_o2 and t_h2o but it seems t_o2 only affects band at 765 nm and t_h2o affects sensor SeaWIFS. For the majority of bands (and sensors), t_o2 and t_h2o are unity,  so have no effect.

Minwei

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Difference between Rhos and Rrc ?

Perfect, thank you !

carros
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