Search found 141 matches

by OB WebDev - norman
Mon Nov 30, 2020 8:47 am America/New_York
Forum: Home
Question: MODIS AQUA Quality Flags
Replies: 8

MODIS AQUA Quality Flags

I'm not sure what you are asking here. Are you referring to these flags?

https://oceancolor.gsfc.nasa.gov/atbd/ocl2flags/

Those flag values are either on or off, making a difference computation somewhat meaningless.

Regards,
Norman
by OB WebDev - norman
Mon Nov 30, 2020 8:42 am America/New_York
Forum: Home
Question: MODIS AQUA SST Daytime Data
Replies: 2

MODIS AQUA SST Daytime Data

In general, you should prefer the more recently produced data.  Products are initially generated as "quicklook" files.  These are regenerated once we have received all the ancillary data needed to produce our "refined" products.  We also reprocess our data sets fro...
by OB WebDev - norman
Wed Sep 16, 2020 9:22 am America/New_York
Forum: Home
Question: Cloud Masking
Replies: 3

Cloud Masking

Hi Amita,I will leave it to the SeaDAS experts to answer the SeaDAS related questions.After using l2gen to generate rhos_8xx products, I usually map the data to a 16-bit imageand then use Gimp Colors->Levels... to interactively choose a threshold that separatesland and clouds from water.  The t...
by OB WebDev - norman
Fri Sep 11, 2020 11:36 am America/New_York
Forum: Home
Question: Data processing
Replies: 4

Data processing

You can generate a list of URLs for files to download by using our L1 browser.Specify your region and time period of interest, click "Find swaths", and then click "ORDER DATA" and follow the instructions.  You can get more information by clicking on the "Help" butt...
by OB WebDev - norman
Fri Sep 11, 2020 9:54 am America/New_York
Forum: Home
Question: Data processing
Replies: 4

Data processing

You have left out key portions of your script, but here is a method that works for me to download Aqua/MODIS L1 files for the month of January 2020.for f in `wget -q --post-data="sensor=aqua&sdate=2020-01-01&edate=2020-01-31&dtype=L1&results_as_file=1&addurl=1&std_only=1...
by OB WebDev - norman
Wed Aug 26, 2020 5:21 pm America/New_York
Forum: Home
Question: OLI L2 data
Replies: 6

OLI L2 data

Hi Amita,

There is a tool at the bottom of this page that might help you understand the l2_flags.

https://oceancolor.gsfc.nasa.gov/atbd/ocl2flags/

Try entering 2112 in the field at the bottom right.

Regards,
Norman
by OB WebDev - norman
Thu Aug 20, 2020 4:05 pm America/New_York
Forum: Home
Question: L2gen processing speed
Replies: 8

L2gen processing speed

by OB WebDev - norman
Tue Jul 21, 2020 9:00 am America/New_York
Forum: Home
Question: VIIRS-JPSS1 OCSSW commands L1A to L2
Replies: 4

VIIRS-JPSS1 OCSSW commands L1A to L2

"...don't forget to include par=V2020099121800.L1A_JPSS1.nc.anc ...without that, you've pulled the ancillary files but didn't tell l2gen to use them"

Huh.  I've been doing it wrong for a couple of years now.
Thanks for the heads up.

Norman
by OB WebDev - norman
Tue Jul 21, 2020 8:48 am America/New_York
Forum: Home
Question: VIIRS-JPSS1 OCSSW commands L1A to L2
Replies: 4

VIIRS-JPSS1 OCSSW commands L1A to L2

Hi Andrew,Make sure you have the VIIRSJ1 bundle installed (install_ocssw.py --viirsj1) and thendo something like the following.getanc.py V2020099121800.L1A_JPSS1.ncl2gen ifile=V2020099121800.L1A_JPSS1.nc geofile=V2020099121800.GEO-M_JPSS1.nc ofile=V2020099121800.L2.nc l2prod=rhos_445,rhos_556,rhos_6...
by OB WebDev - norman
Fri Jul 17, 2020 8:46 am America/New_York
Forum: Home
Question: Damaged MODISA L2 file
Replies: 1

Damaged MODISA L2 file

Hi Marco,

That scene and the one before it and the one after it are corrupt (perhaps during
transmission to the ground station).  Sometimes we get better data later from
our providers.

Norman