Search found 85 matches

by blesht
Wed Sep 04, 2019 9:19 am America/New_York
Forum: Questions/Comments
Question: Why the change in MODIS band-averaged aw(lambda) and bbw(lambda) in 2019?
Replies: 2

Why the change in MODIS band-averaged aw(lambda) and bbw(lambda) in 2019?

Good morning, Sean.  Thanks for the explanation.   As I noted, this came up as part of my attempt to port qaa.c to R so I can use it in some external applications.  If I understand correctly, I should be using the aw and bbw values that show up in the output L2 netcdf file to be ...
by blesht
Tue Sep 03, 2019 4:28 pm America/New_York
Forum: Questions/Comments
Question: Why the change in MODIS band-averaged aw(lambda) and bbw(lambda) in 2019?
Replies: 2

Why the change in MODIS band-averaged aw(lambda) and bbw(lambda) in 2019?

Hi - I've been struggling with trying to port the SeaDAS version of QAAv6 (qaa.c) to R.  It should be a simple thing to do, but I can't get my code to reproduce the same values of a_488_qaa and b_488_qaa that come from SeaDAS (v7.5) when given the same input Rrs spectrum.  The deta...
by blesht
Thu Aug 29, 2019 8:53 pm America/New_York
Forum: Questions/Comments
Question: Why isn't Lee_Kd_PAR * Zeu_lee a constant for all pixels?
Replies: 2

Why isn't Lee_Kd_PAR * Zeu_lee a constant for all pixels?

Ah (or should that be 'Doh'?)    Thanks, Sean.  So, if instead of using p.prod_ix = -3, zphotic_lee had been called with p.prod_ix = -2, the resultant Kd would be the calculated Kd to the 1% level and then product with Zeu_lee would be a constant.  The output value of Zeu...
by blesht
Mon Aug 26, 2019 10:08 pm America/New_York
Forum: Questions/Comments
Question: Why isn't Lee_Kd_PAR * Zeu_lee a constant for all pixels?
Replies: 2

Why isn't Lee_Kd_PAR * Zeu_lee a constant for all pixels?

Hi.  I create L2 files using l2gen often adding variables of interest to me, such as Zeu_lee and Kd_PAR_lee.  I've checked the source codes (get_Kd.c and photic_depth.c) and Kd_PAR_lee is obtained simply by inverting Zeu_lee.  The relevant lines of Kd_PAR_lee are:Zphotic_lee(l2rec...
by blesht
Fri Aug 02, 2019 1:50 pm America/New_York
Forum: Questions/Comments
Question: Quick question about blended chlor_a algorithm
Replies: 2

Quick question about blended chlor_a algorithm

Hey Sean!  Thank you.   Being an old hand at this, I did look at the source code but I guess, also being an old man, I read right past (or just didn't see) the relevant part. 

Best regards, Barry
by blesht
Fri Aug 02, 2019 12:00 pm America/New_York
Forum: Questions/Comments
Question: Quick question about blended chlor_a algorithm
Replies: 2

Quick question about blended chlor_a algorithm

Hi - Current implementation of the chlor_a algorithm blends the Hu CI and O'Reilly OCx algorithms.   There are two threshold values that are used to switch between the two.  The documentation states when chl < 0.15 mg/m^3 CI is used and when chl > 0.2 mg/m^3 OCx is used (weighted ...
by blesht
Tue Jul 30, 2019 7:11 pm America/New_York
Forum: Questions/Comments
Question: Did something change in VIIRS day_night_flag in 2017?
Replies: 3

Did something change in VIIRS day_night_flag in 2017?

Hi Gene - thanks for both the explanation and the fix.   I do appreciate it.   Regards, Barry
by blesht
Wed Jul 24, 2019 5:56 pm America/New_York
Forum: Questions/Comments
Question: Did something change in VIIRS day_night_flag in 2017?
Replies: 3

Did something change in VIIRS day_night_flag in 2017?

Hi - This seems strange.  I've been running through the entire VIIRS mission doing match-ups with in situ observations collected in the Great Lakes.  My match-up routine is coded in IDL.  The code happily chunks through the data from 2012-2016 but then stops with an error ("H...
by blesht
Sat Jul 20, 2019 11:27 am America/New_York
Forum: Questions/Comments
Question: Oh, do I miss out_track
Replies: 14

Oh, do I miss out_track

Good morning, George.  Your first comment about why my MacPorts installation didn't work led me to go back and try the whole process again.  I must have done something wrong the first time I attempted it because now it works fine.  I suspect that my I issued the 'sudo port sel...
by blesht
Fri Jul 19, 2019 8:29 pm America/New_York
Forum: Questions/Comments
Question: Oh, do I miss out_track
Replies: 14

Oh, do I miss out_track

Hi George - Good to hear from you.  How are you doing?  Thanks!  Well, since I did the anaconda python installation this afternoon, this is what I get (not unexpected).bash-3.2$ head -1 mk_matchup.py#!/usr/bin/env python3bash-3.2$ bash-3.2$ python3 --versionPython 3.7.3bash-3.2$ which...