Hi afnanullah279
Looked into this a bit: Optical_Depth_055 refers to Green band aerosol optical depth, according to the user guide the description for AOD uncertainty states: AOD uncertainty: This parameter is evaluated based on the Blue-band B3 surface
brightness (reflectance) only, and thus gives only a general indication of possible increase
of error over brighter surfaces.
I believe you should only need the QA and not the AOD uncertainty since you are interested in the green band optical depth (Optical_Depth_055).
Unfortunately because of the complexity that the extra dimensions bring data will need to be subsetted after the tiles are downloaded.
We do have the LDOPE tools available that can help you unpack the QA bits, specifically the unpack_sds_bits.exe. You may also find the create_mas.exe usefull also: https://lpdaac.usgs.gov/tools/ldope/
Thanks,
Brett
Looked into this a bit: Optical_Depth_055 refers to Green band aerosol optical depth, according to the user guide the description for AOD uncertainty states: AOD uncertainty: This parameter is evaluated based on the Blue-band B3 surface
brightness (reflectance) only, and thus gives only a general indication of possible increase
of error over brighter surfaces.
I believe you should only need the QA and not the AOD uncertainty since you are interested in the green band optical depth (Optical_Depth_055).
Unfortunately because of the complexity that the extra dimensions bring data will need to be subsetted after the tiles are downloaded.
We do have the LDOPE tools available that can help you unpack the QA bits, specifically the unpack_sds_bits.exe. You may also find the create_mas.exe usefull also: https://lpdaac.usgs.gov/tools/ldope/
Thanks,
Brett
Statistics: Posted by LP DAAC - lien — Tue Jan 09, 2024 3:47 pm America/New_York