The forum is locked.
The Ocean Color Forum has transitioned over to the Earthdata Forum (https://forum.earthdata.nasa.gov/). The information existing below will be retained for historical reference. Please sign into the Earthdata Forum for active user support.
Topic SeaDAS / MODIS Direct Broadcast Support / Problem with MOD09/DBBRDF product since upgrade to Seadas 6.4 (locked)
Hi,
We updated from Seadas 6.2 to 6.4 for our MODIS DB processing & have since experienced problems with using MOD09 data in DBBRDF (MOD43) code & we were wondering if anyone else had similar problems.
Basically, we take output from Seadas & create MOD09 using IMAPP then input this into DBBRDF MOD43 Phase 1 code to get MOD09GA tiles. This is part of our process chain to create 8-day MOD09A1 composites for Grassland Curing for Fire Agencies.
However, since upgrading to Seadas 6.4 the DBBRDF MOD43 Phase 1 code no longer recognises our DB MOD09 input files. We tested the MOD43 code with NASA MOD09 files and it works fine. Has anyone else had this problem or similar problems with MOD09 created from L1B outputted from Seadas 6.4?
What could have changed in Seadas 6.4 that would cause this to happen?
We updated from Seadas 6.2 to 6.4 for our MODIS DB processing & have since experienced problems with using MOD09 data in DBBRDF (MOD43) code & we were wondering if anyone else had similar problems.
Basically, we take output from Seadas & create MOD09 using IMAPP then input this into DBBRDF MOD43 Phase 1 code to get MOD09GA tiles. This is part of our process chain to create 8-day MOD09A1 composites for Grassland Curing for Fire Agencies.
However, since upgrading to Seadas 6.4 the DBBRDF MOD43 Phase 1 code no longer recognises our DB MOD09 input files. We tested the MOD43 code with NASA MOD09 files and it works fine. Has anyone else had this problem or similar problems with MOD09 created from L1B outputted from Seadas 6.4?
What could have changed in Seadas 6.4 that would cause this to happen?
The biggest change with 6.4 was with the calibration LUTs for the L1B product. There were other L1B code changes in that affected the flag settings.
It may be possible that these changes may be the culprit.
These changes are not specific to SeaDAS, as the MODIS code we distribute comes from MCST. However, we
do distribute a version that is not in the forward stream for other disciplines (including Land) - rather a version that MCST is preparing for use, but
have yet to be implemented with the reprocessing schedule for the other disciplines. Oceans has a more rapid requirement for reprocessing and
we work with MCST to get the latest code changes into our production sooner.
You could grab an L1B file from LAADS and compare it to one produced from SeaDAS to see the differences. A quick comparison shows very minor
and likely inconsequential differences...
Sean
It may be possible that these changes may be the culprit.
These changes are not specific to SeaDAS, as the MODIS code we distribute comes from MCST. However, we
do distribute a version that is not in the forward stream for other disciplines (including Land) - rather a version that MCST is preparing for use, but
have yet to be implemented with the reprocessing schedule for the other disciplines. Oceans has a more rapid requirement for reprocessing and
we work with MCST to get the latest code changes into our production sooner.
You could grab an L1B file from LAADS and compare it to one produced from SeaDAS to see the differences. A quick comparison shows very minor
and likely inconsequential differences...
Sean
Hey,
I can confirm this has happened to us too, internally DBBRDF appears to not like parts of the geolocation files generated by SeaDAS 6.4 and refuses to get various metadata fields from it as a result (due to exiting early).
Did you happen to make any progress on this P.Loto_aniu? At this rate we're going to have to duplicate our processing efforts for what 'should' be compatible data.
Cheers,
Mitch
I can confirm this has happened to us too, internally DBBRDF appears to not like parts of the geolocation files generated by SeaDAS 6.4 and refuses to get various metadata fields from it as a result (due to exiting early).
Did you happen to make any progress on this P.Loto_aniu? At this rate we're going to have to duplicate our processing efforts for what 'should' be compatible data.
Cheers,
Mitch
Topic SeaDAS / MODIS Direct Broadcast Support / Problem with MOD09/DBBRDF product since upgrade to Seadas 6.4 (locked)