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Querying OBPG VIIRS L2 granules through CMR
Posted: Tue May 27, 2025 11:20 am America/New_York
by alaroy
We're looking to query OBPG generated VIIRS products through CMR and not finding what we expect.
I would specifically like to query L2 Ocean Color (OC) NRT granules on a global basis for all of the VIIRS instruments. When I look in the earth data search tool I am only finding regional entries. Am I missing something or have global CMR collections for these products not been set up yet?
I find similar issues when I look for VIIRS (NPP and NOAA-20) L2 NRT sea surface temperature data.
If the CMR collections have not been set up yet, roughly when will they be set up? I'm just trying to plan our work ahead.
Thank you for any pointers!
-Andrew L.
Re: Querying OBPG VIIRS L2 granules through CMR
Posted: Tue May 27, 2025 1:22 pm America/New_York
by OB ODPS - towens
The L2 granules are each "regional". They combine to give global coverage.
Tommy
Re: Querying OBPG VIIRS L2 granules through CMR
Posted: Wed May 28, 2025 10:43 am America/New_York
by alaroy
Thank you for your reply. So as I suspected I was missing something
So the "regional" in the product name is referring to the granules not the level of global coverage. Sort of like the MODIS "Local Area Coverage" granules being able to generate a global data set when combined.
I'm still confused about which collection to use. For example for VIIRS abord NOAA-20 there are the following CMR collections:
"NOAA-20 VIIRS Level-2 Regional Ocean Color (OC) - Near Real-time (NRT) Data, version 2022.0" (C3396928895-OB_CLOUD)
and
"NOAA-20 VIIRS Regional Ocean Color (OC) - Near Real Time (NRT) Data, version R2022.0" (C2340494496-OB_DAAC)
What are the differences between the two? I notice that ...496-OB_DAAC has significantly more granules than ...895-OB_CLOUD, so I'm guessing that 496 is the right one to use - but I don't know why.
Thank you, as always, for whatever guidance you can give me!
-Andrew L.
Re: Querying OBPG VIIRS L2 granules through CMR
Posted: Wed May 28, 2025 11:04 am America/New_York
by OB ODPS - towens
The R2022.0 collection is the original CMR collection that points to the OB_DAAC servers at GSFC, and the 2022.0 is the new Earthdata Cloud hosted OB_CLOUD collection that points to AWS. The R2022.0 CMR collections will be deprecated shortly, so you should point your code development at the Cloud version.(2022.0)
Tommy
Re: Querying OBPG VIIRS L2 granules through CMR
Posted: Wed May 28, 2025 1:29 pm America/New_York
by alaroy
That's great information to know, thank you Tommy! I adjusted our scripts to use the OB_CLOUD collection id's.
I noticed that he 11 nm SST L2 data only seems to have OB_DAAC collection id's. Are they going to get depreciated too at some point?
Re: Querying OBPG VIIRS L2 granules through CMR
Posted: Wed May 28, 2025 1:51 pm America/New_York
by OB ODPS - towens
No, the MODIS and VIIRS SST that we produce are not moving to the Cloud archive - they will continue to be archived locally and those collections will not change.
Re: Querying OBPG VIIRS L2 granules through CMR
Posted: Wed May 28, 2025 3:00 pm America/New_York
by alaroy
Tommy - great to know that. I think that's all my questions, at least for now
