Night files being found in VIIRS subscription day only

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oo_processing
Posts: 206
Joined: Wed Apr 06, 2005 12:11 pm America/New_York

Night files being found in VIIRS subscription day only

by oo_processing » Thu Jul 02, 2020 12:59 pm America/New_York

I am getting night passes in my new VIIRS glakes subscription
https://oceandata.sci.gsfc.nasa.gov/subscriptions/sub/2512/
Note:
https://oceandata.sci.gsfc.nasa.gov/api/file_search?subID=2512&subType=1

V2020183084800.L1A_SNPP.nc 
V2020183103000.L1A_SNPP.nc 

Also note the files found on the L1/2 browser when looking for yesterday's day passes (oddly I only get a L2 list and not L0):
V2020183165400.L2_SNPP_OC.nc
V2020183170000.L2_SNPP_OC.nc
V2020183183600.L2_SNPP_OC.nc

A previous search of the L1/2 browser brought up the viirs L0 list (what am I missing above? I only want the L0s not the L2)

V2020183165400.L1A_SNPP.nc
V2020183170000.L1A_SNPP.nc
V2020183183600.L1A_SNPP.nc

Note the last 2 images. The results one doen't have the L0 next to List, and returns:
https://oceancolor.gsfc.nasa.gov/cgi/browse.pl/filelist.1593709866.txt?sub=filenamelist&id=1593709866.12219&prm=CHL

V2020183165400.L2_SNPP_OC.nc
V2020183170000.L2_SNPP_OC.nc
V2020183183600.L2_SNPP_OC.nc



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OB ODPS - jgwilding
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Posts: 110
Joined: Fri Feb 19, 2021 1:09 pm America/New_York

Night files being found in VIIRS subscription day only

by OB ODPS - jgwilding » Thu Jul 02, 2020 10:03 pm America/New_York

These two files are tagged with day-night-flag = 3, which means day 1 and night 2.  Subscriptions for daytime data will get any granule identified as having daytime data regardless of the amount. The same would be true for nighttime subscriptions.

daynightflag: 3
basename:     V2020183084800.L1A_SNPP.nc

daynightflag: 3
basename:     V2020183103000.L1A_SNPP.nc

I wasn't aware that we were distributing VIIRS L0 data that way.  The VIIRS L0 data are ~90-minute (session based) and 2-hr (time base) files containing all of the data for that period not the one-to-one type of arrangement as seen for the MODIS missions.  We have no way to produce a L0 granule for a specific scene.

john

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