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Hi Cortivo, The code looks correct to me. In l2gen's function chl_oci, chl_hu (per Hu et al 2012) is denoted as chl1 and chl_ocx (band ratio) is denoted as chl2. The decision point in the function chl_oci that selects chl_hu, chl_ocx, or a blend of the two, is dependent only the magnitude of chl_hu ...

Hi Toru,

I agree that as per the QAA v5/v6 documentation, the reflectance terms in lines 241-242 and 327-328 probably should be sub-surface and not above-water reflectances. I shall look into this further.

Best regards,
Lachlan

Don - I've been working with Tess to get ocssw built on an old CentOS machine. Looks like I shared the wrong version of opt/src. I think we're getting closer to this building properly now. I will contact you directly with further detail.

Cheers,
Lachlan

Hi Bruce,I usually run my code on a linux box, however, I have a previously compiled version of ocssw on my mac that works successfully.For my version of l2gen, which I built back in October, I get the following when I run "otool -L $OCSSWROOT/bin/l2gen": @rpath/libhdf5_hl.10.2.1.dylib (co...

Hi Sunanda,Unfortunately, it is hard to diagnose an issue without further information. Specifically:(1) what is the L1A file you are analyzing (file name, date, location, sensor)(2) what values are "missing" and from which bands?(3) which file has missing values (distributed L2 file, or th...

Hi Marjan,This is a challenging question to answer as there are a number of different PFT algorithms out there. All I can do is recommend you consult the literature. The following paper is probably a good starting point:Mouw et al. 2017. A Consumer's Guide to Satellite Remote Sensing of Multiple...

Hmmm, as I'm sure you're aware applying ocean color data with ~1km pixel resolution to lakes can be problematic. My suggestion was going to be to empirically scale the standard chlorophyll algorithm for MODIS using in situ data rather than retuning the OC algorithm coefficients. However, if ...

Hi Jade,PAR is a daily-integrated product and I am unsure how you propose to deconvolve it into hourly values. I presume it *could* be done given temporal information regarding solar position, however, it would still be difficult to account for daily variability in atmospheric conditions.Alternative...

Hi Africa,I presume you are doing some sort of regional study and I do have some thoughts regarding your query. Before I give an extended response, it would be useful to get an idea of where you're looking and what your objectives are. 1. Are you working in optically complex and/or shallow condi...

Hi Amaru,For further details on the Lee et al. euphotic zone depth algorithm formulation, see:Lee et al. 2007. "Euphotic zone depth: Its derivation and implication to ocean-color remote sensing", JGR, 112(C03009), doi:10.1029/2006JC003802. As I understand (please correct me if I'm wron...