caicos-ETM_009_045_2007-12-15

        


 
1 - NO NEED for field data, nor for atmospheric correction
2 - this is demonstrated in this website, using a variety of hyper/multi spectral data
 
Requirements are
1 - homogeneous water body and atmosphere
2 - some coverage of optically deep water
3 - some coverage of dry land
 
Problems are
1 - the precision on estimated depth is found wanting, because the noise-equivalent change in radiance  of accessible data is too high for shallow water column correction work 
2 - radiance data should be preprocessed by the provider at level 1 in order to improve S/N ratio
3 - exponential decay: the deeper/darker the bottom, the poorer the performances
 
So
I keep digging
until suitable data
become available
 
 
caicos-ETM_009_045_2007-12-15


Final calibration diagram


  • Knir~=4.5
  • -cWL/0.500/0.600/0.200/0.500
  • -dLsw0000/01.0/0000/0000
  • Purple colors: notice the foul radiances in the Red band in the south-west area: this causes bad underestimation of depth, and requires that Lmred be set at a high value
DIFFICULT

SLCoff: 125 depth points are "nodata"
 
PlotZ23
 
RLBbg=1.00

PlotZ23
  RLBbg=1.10