Search found 14 matches

by lmckinna
Mon Oct 12, 2020 12:34 am America/New_York
Forum: All Questions/Comments
Question: QAA source code of l2gen
Replies: 4

QAA source code of l2gen

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
by lmckinna
Wed Jul 01, 2020 8:09 pm America/New_York
Forum: All Questions/Comments
Question: make command error when building ocssw binaries
Replies: 4

make command error when building ocssw binaries

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
by lmckinna
Tue Jan 01, 2019 11:38 pm America/New_York
Forum: All Questions/Comments
Question: Missing Library: libhdf5_hl.10.3.0.dylib
Replies: 4

Missing Library: libhdf5_hl.10.3.0.dylib

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...
by lmckinna
Tue Jan 01, 2019 6:55 pm America/New_York
Forum: All Questions/Comments
Question: how to derive reflectance values for all the bands in MODIS
Replies: 2

how to derive reflectance values for all the bands in MODIS

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...
by lmckinna
Tue Oct 16, 2018 6:02 am America/New_York
Forum: All Questions/Comments
Question: Phytoplankton functional type (PFD) models for Arctic area
Replies: 1

Phytoplankton functional type (PFD) models for Arctic area

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...
by lmckinna
Wed Sep 19, 2018 12:56 am America/New_York
Forum: All Questions/Comments
Question: Algorithm calibration using in situ data
Replies: 5

Algorithm calibration using in situ data

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 ...
by lmckinna
Sat Sep 15, 2018 3:37 am America/New_York
Forum: All Questions/Comments
Question: Code for PAR daily to hourly
Replies: 1

Code for PAR daily to hourly

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...
by lmckinna
Sat Sep 15, 2018 3:24 am America/New_York
Forum: All Questions/Comments
Question: Algorithm calibration using in situ data
Replies: 5

Algorithm calibration using in situ data

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...
by lmckinna
Tue Jul 10, 2018 3:25 am America/New_York
Forum: All Questions/Comments
Question: Questions about Zeu Lee
Replies: 2

Questions about Zeu Lee

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...
by lmckinna
Thu Apr 19, 2018 6:14 am America/New_York
Forum: All Questions/Comments
Question: L1B - L2 l2gen very slow
Replies: 5

L1B - L2 l2gen very slow

Hi James,Please note that the tsm_swim product is an evaluation product that was developed for optically shallow coral reef waters. The idea was to estimate tsm from the magnitude of derived particulate backscattering coefficient. I would not recommend using the product (I developed it, so feel qual...