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Missing MODIS v6.1 data on Dec 22 2023

Posted: Thu Dec 28, 2023 2:24 pm America/New_York
by kpotapov
Hi,

It appears that some MOD09GA and MOD09GQ data is missing on Dec 22 2023. Specifically, the following h, v coordinates are missing: h=10, v=7; h=10, v=8; h=10, v=9 (and some others in that vicinity).

The CMR API appears to be missing this data, as well as the following servers:
https://e4ftl01.cr.usgs.gov/MOLT/MOD09GQ.061/2023.12.22/
https://ladsweb.modaps.eosdis.nasa.gov/archive/allData/61/MOD09GA/2023/356

Do you know if this data will become available?

All the best,
Katya

Re: Missing MODIS v6.1 data on Dec 22 2023

Posted: Fri Dec 29, 2023 11:37 am America/New_York
by LP DAAC - lien
Hi Katya,
We are checking with the data provider on this. As soon as I hear something, I will let you know.
Please see the Global Browse image: https://landweb.modaps.eosdis.nasa.gov/cgi-bin/QS/browse/details.cgi?SENSOR=Terra&VER=061&ESDT=MOD09CMG&DATASET=MOD09CMG&YEAR=2023&DATE=A2023356

So there is a gap, we are checking to see if it is recoverable.
Thanks,
Brett

Re: Missing MODIS v6.1 data on Dec 22 2023

Posted: Fri Dec 29, 2023 2:31 pm America/New_York
by kpotapov
Hi Brett,

Thanks for the update, please keep me posted.

All the best,
Katya

Re: Missing MODIS v6.1 data on Dec 22 2023

Posted: Fri Jan 19, 2024 2:53 pm America/New_York
by LP DAAC - lien
Hi Katya,
Sorry for the delay. They are not recoverable, unfortunately this will occur more often as the Terra and Aqua platforms orbit decays. Please see the following also:

Data gaps or missing data have become more of a routine occurrence for Terra, Aqua, and Terra+Aqua Combined MODIS data products. On July 7, 2023, the MODIS Flight Operations Team transitioned to a new schedule and no longer attempts to recover Level 0 data if the missed contact happens after regular business hours. Once data gaps that have occurred during the Light-Out-Operations LOOps (https://landweb.modaps.eosdis.nasa.gov/cgi-bin/QA_WWW/displayCase.cgi?esdt=MOD&caseNum=HC_MOD_23226&caseLocation=cases_data&type=C61&_gl=1*2ygb62*) period from 6 pm to 6 am Eastern time have been confirmed, the data loss events will be added to the list of dates and times of the known LOOps events.

Terra MODIS (https://landweb.modaps.eosdis.nasa.gov/cgi-bin/QA_WWW/displayCase.cgi?esdt=MOD&caseNum=TM_MOD_23233&caseLocation=cases_data&type=C61)
Aqua MODIS (https://landweb.modaps.eosdis.nasa.gov/cgi-bin/QA_WWW/displayCase.cgi?esdt=MYD&caseNum=TM_MYD_23233&caseLocation=cases_data&type=C61)

All Terra, Aqua, and Combined Terra+Aqua MODIS Version 6.1 data products are directly impacted by the non-recoverable data loss.

This may or may not be the reason, as you can see by the Global Browse and the Orbit tracks it looks like most of 2 tracks are not recoverable: https://www.ssec.wisc.edu/datacenter/polar_orbit_tracks/data/TERRA/2023/2023_12_22_356/GLOBAL.gif

Thanks for understanding.
Brett

Re: Missing MODIS v6.1 data on Dec 22 2023

Posted: Mon Jan 22, 2024 3:07 pm America/New_York
by kpotapov
Hi Brett,
No worries, thanks for the detailed response. We'll keep this in mind and monitor the known LOOps events page for future data outages.

All the best,
Katya