VIIRS L1A extract download

Please enter here to ask a question about any NASA Science related topics!
Post Reply
schckngs
Posts: 23
Joined: Wed Feb 03, 2021 1:43 pm America/New_York

VIIRS L1A extract download

by schckngs » Wed Oct 24, 2018 9:46 pm America/New_York

Hey,
I downloaded L1A VIIRS data for 2012-2013 from the L1&2 browser and am getting data mostly outside the study area. I specified a region around Vancouver Island to extract the data (47.0 - 51.5 N, 128.5 - 122.0 W), but ended up with granules of differing sizes across north america. Is this functionality not set up for VIIRS data, or maybe I ordered it incorrectly?
Thanks,
Andrea

Tags:

OB WebDev - norman
Subject Matter Expert
Subject Matter Expert
Posts: 136
Joined: Tue Feb 09, 2021 8:19 am America/New_York

VIIRS L1A extract download

by OB WebDev - norman » Thu Oct 25, 2018 8:57 am America/New_York

Hi Andrea,

Could you be more specific about the steps you followed?  When I search the time and region you indicate, I get the following results.

https://oceancolor.gsfc.nasa.gov/cgi/browse.pl?sub=level1or2list&per=CSTM&day=15340+731&sen=v0&hlt=1&frc=0.25&n=51.5&s=47&w=-128.5&e=-122&dnm=D&prm=TC

The resulting scenes all appear to include at least a portion of your
region of interest (note the red highlights).

Regards,
Norman

schckngs
Posts: 23
Joined: Wed Feb 03, 2021 1:43 pm America/New_York

VIIRS L1A extract download

by schckngs » Thu Oct 25, 2018 1:13 pm America/New_York

Hi Norman,
I followed the data ordering process (specifying date range and coordinates) and got the same as you, thumbnails with the AOI, and specified to extract the data after clicking the 'ORDER DATA' button. However, during processing to L2 I did not use the DEM to generate GEO files, but downloaded GEO files separately, corresponding to the L1A filename. I am thinking this discrepancy (downloading the full GEO file and using with an extracted L1A) might be the source of my issue...
-Andrea

OB WebDev - norman
Subject Matter Expert
Subject Matter Expert
Posts: 136
Joined: Tue Feb 09, 2021 8:19 am America/New_York

VIIRS L1A extract download

by OB WebDev - norman » Thu Oct 25, 2018 1:47 pm America/New_York

Hi Andrea,

Yes you need to generate GEO files from your extracts.
You can use this script.

https://seadas.gsfc.nasa.gov/help/seadas-processing/ProcessModis_GEO.py.html

Regards,
Norman

schckngs
Posts: 23
Joined: Wed Feb 03, 2021 1:43 pm America/New_York

VIIRS L1A extract download

by schckngs » Thu Oct 25, 2018 1:55 pm America/New_York

Thanks Norman, not just MODISA files?

schckngs
Posts: 23
Joined: Wed Feb 03, 2021 1:43 pm America/New_York

VIIRS L1A extract download

by schckngs » Thu Oct 25, 2018 2:26 pm America/New_York

It's working fine with geolocate_viirs now, sorry for taking up forum space. ;)

OB WebDev - norman
Subject Matter Expert
Subject Matter Expert
Posts: 136
Joined: Tue Feb 09, 2021 8:19 am America/New_York

VIIRS L1A extract download

by OB WebDev - norman » Thu Oct 25, 2018 5:05 pm America/New_York

Sorry.  I got my sensors mixed up.  Glad you figured it out.

Norman

Post Reply