two questions

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slava.suslin
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Joined: Tue Feb 16, 2021 1:51 am America/New_York

two questions

by slava.suslin » Wed Feb 12, 2020 2:49 am America/New_York

Good day,

1. what is a relationship between 

OLCI water-leaving reflectance (https://sentinel.esa.int/web/sentinel/technical-guides/sentinel-3-olci/level-2/products-description ) (ESA’s level-2 product)
and
Remote Sensing Reflectance (Rrs; sr-1) (NASA’s level-2 product)?

2. Does your group plan to generate and to access the OLCI level-2 data to oceancolor community?

Thank you.
slava

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OB.DAAC - SeanBailey
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two questions

by OB.DAAC - SeanBailey » Fri Feb 14, 2020 1:49 pm America/New_York

Slava,

The difference between water leaving reflectance (rho_w) and remote sensing reflectance (Rrs) is a factor of PI.

Yes, we do plan to generate and make available OLCI level-2 data processed consistently with all of the missions we support.
We are currently in the process of evaluating the vicarious calibration for both OLCI on both the S3A and S3B platforms.  Once we have verified our calibration, we will initiate the processing of OLCI to Level-2 and Level-3.

Regards,
Sean

slava.suslin
Posts: 29
Joined: Tue Feb 16, 2021 1:51 am America/New_York

two questions

by slava.suslin » Mon Feb 17, 2020 1:51 am America/New_York

Sean,

thank You

slava

beiral
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Joined: Mon Feb 11, 2019 3:12 pm America/New_York

two questions

by beiral » Thu Mar 19, 2020 11:23 am America/New_York

Hi all!
The product of MODIS equivalent to water leaving reflectance is rhos? Or do I need to calculate Rrs*Pi?
Thanks for any help!!

OB.DAAC - SeanBailey
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two questions

by OB.DAAC - SeanBailey » Thu Mar 19, 2020 11:41 am America/New_York

The rhos product is what we refer to as "surface reflectance", although that is a bit of a misnomer.  It is simply Rayleigh corrected TOA radiance, so it includes surface + aerosol reflectance.
Assuming a Lambertian surface, yes water leaving reflectance (R) would be Rrs*pi.  For a comprehensive answer, see:
http://www.oceanopticsbook.info/view/atmospheric_correction/normalized_reflectances

Sean

beiral
Posts: 14
Joined: Mon Feb 11, 2019 3:12 pm America/New_York

two questions

by beiral » Thu Mar 19, 2020 3:33 pm America/New_York

Thank you very much for your help Sean...Regards!

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