Optical calibration, bathymetry, water column correction and bottom typing of shallow marine areas, using passive remote sensing imageries
 
  
Bathymetry and water column correction
World View 2 image Princess Cays,
Eleuthera island, Bahamas

 

 November 11th 2011, 7200*12515, 2 m ground resolution
  "(c) DigitalGlobe, Inc. All Rights Reserved"
"Includes copyrighted material of DigitalGlobe, Inc., All Rights Reserved"


This dataset from Digital Globe under Data Exchange Agreement,
MULTI + PANchromatic
is a fine example of using the PAN band along with MULTI bands
for shallow water work



 
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
 
 

princesscays Multi
uses only MULTI bands
 
princesscays Multi+Pan
uses PAN in addition to MULTI bands