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Inconsistencies in tau_r, K_O2, and K_NO2 coefficients

Posted: Thu Jul 13, 2023 7:04 pm
by gbourdin
Hello François,
I have modified

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./polymer/level1_nasa.py 
and

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./polymer/params
to add VIIRS-JPSS2 tau_r, K_O2, and K_NO2 (from NASA-OceanColor website: https://oceancolor.gsfc.nasa.gov/resour ... sr_tables/) and add support for VIIRS-JPSS2 in POLYMER, it seems to work well.
It would be great to include it to the next release.
I have noticed some inconsistencies between the coefficients in POLYMER and the ones in the table on the NASA website (https://oceancolor.gsfc.nasa.gov/resour ... sr_tables/). There is only one set of coefficients for both MODIS and one set for both OLCI although there is one set for each sensor (MODISA, MODIST, OLCI-a, OLCI-b) on the NASA website. Should these coefficients be updated to improve across sensor consistency?

I also found missing coefficients for MSI in

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./polymer/params
:

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self.K_OZ = {   # FIXME: rough values from OLCI
                443 : 2.897E-03,
                490 : 2.066E-02,
                560 : 1.058E-01,
                665 : 5.005E-02,
                705 : 1.887E-02,
                740 : 8.743E-03,
                783 : 7.700E-03,
                842 : 0.,
                865 : 2.156E-03,
                945 : 0.,
                1375: 0.,
                1610: 0.,
                2190: 0.,
                }

        self.K_NO2 = {   # FIXME
                443 : 0.,
                490 : 0.,
                560 : 0.,
                665 : 0.,
                705 : 0.,
                740 : 0.,
                783 : 0.,
                842 : 0.,
                865 : 0.,
                945 : 0.,
                1375: 0.,
                1610: 0.,
                2190: 0.,
                }
Best,
Guillaume

Re: Inconsistencies in tau_r, K_O2, and K_NO2 coefficients

Posted: Tue Aug 08, 2023 2:54 am
by lanzhiqishi
Dear guillaume,

thank you for your sharing.


Best,Binbin

Re: Inconsistencies in tau_r, K_O2, and K_NO2 coefficients

Posted: Mon Aug 21, 2023 12:51 pm
by fsteinmetz
Hi Guillaume,

Thanks for this. Indeed the absorption coefficients would require some more up-to-date and consistent information. I will include this in next Polymer release.
Cheers,
François