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By Ken Rutledge
Date 2004-06-29 14:17
At present, comparing MODIS Ocean and SEAWIFS processing via SEADAS, are the default atmospheric correction methods deployed for the two identical?
Where possible, yes.
Here are the differences:
(the obvious)
gains
calfiles
(the not so obvious)
proc_sst=toggle SST processing (1: On, 0: Off, default=1 for MODIS, 0 otherwise)
pol_opt=polarization correction (MODIS only, default is 3: only Rayleigh and Glint are polarized)
oxaband_opt=oxygen a-band correction option (1: On, 0: Off, default: 1 - for SeaWiFS, OSMI, & OCTS, 0 - otherwise)
If you don't change anything manually, the correct sensor defaults will be assigned.
Regards,
Sean
Here are the differences:
(the obvious)
gains
calfiles
(the not so obvious)
proc_sst=toggle SST processing (1: On, 0: Off, default=1 for MODIS, 0 otherwise)
pol_opt=polarization correction (MODIS only, default is 3: only Rayleigh and Glint are polarized)
oxaband_opt=oxygen a-band correction option (1: On, 0: Off, default: 1 - for SeaWiFS, OSMI, & OCTS, 0 - otherwise)
If you don't change anything manually, the correct sensor defaults will be assigned.
Regards,
Sean
Ken,
The atmospheric correction methods are identical. The only major change for MODIS is that we must account for the high polarization sensitivity of MODIS, which means we must compute full stokes vectors for the atmospheric signal. This adds significant additional uncertainty, as we don't know the poalrization effects due to aerosols, and the laboratory measurements of instrument polarization sensitivity may not adequately characterize the instrument on orbit. Work is underway to develop polarization components for the aerosol models. We continue to evaluate the laboratory characterization of MODIS/Aqua, and we are looking at methods to determine polarization sensitivity vicariously.
-- bryan
(NOTE: I copied this message from Bryan ... ttfn Sean)
The atmospheric correction methods are identical. The only major change for MODIS is that we must account for the high polarization sensitivity of MODIS, which means we must compute full stokes vectors for the atmospheric signal. This adds significant additional uncertainty, as we don't know the poalrization effects due to aerosols, and the laboratory measurements of instrument polarization sensitivity may not adequately characterize the instrument on orbit. Work is underway to develop polarization components for the aerosol models. We continue to evaluate the laboratory characterization of MODIS/Aqua, and we are looking at methods to determine polarization sensitivity vicariously.
-- bryan
(NOTE: I copied this message from Bryan ... ttfn Sean)