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the Self-calibrated Supervised Spectral Shallow-sea Modeler

Passive optical calibration, bathymetry retrieval, water column correction
and bottom typing of shallow water areas using remote sensing imageries


Use passive hyperspectral or multispectral satellite images to retrieve both
depth and spectral reflectance of shallow bottom, ready for bottom typing, ahead of any field work


Breaking news May 2nd 2014:
4SM demonstration: 40 times faster than best ALLUT process on the same image


   r   
 
 


 
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
 
Leave difficult cases
to semi-analytical methods!
Further to Lyzenga et al's empirical ratio method: water volume reflectance is an important variable.
No need for atmospheric correction.
Uses Jerlov's data for optical calibration.

Optical calibration does not need any field data:
the image itself contains all the information that is needed for a "ratio method"

 

Users of Geomatica, ENVI, Erdas, TNTmips, ERmapper, Ilwis, Idrisi, etc,
 no sweat: I only use open source 

            
Just use a X86 or AMD64 laptop
running Linux
From importing raw data to formating deliverables in one single 4SM executable code.
Uses a bash command line, focussed on productivity.
 
 
Albert & Mobley's analytical model, 2003, is used commercially by EOMAP and PROTEUS

 
HELP!
For operational purpose, we need a way out: 
the simplified shallow water Radiative Transfer Equation
1989  ...BOA by Philpot     
1994  ...BOA by Maritorena et al

Following Lyzenga, Maritorena, Jerlov and Kirk, passive optical bathymetry is operational and practical

 "operates" the simplified shallow water RTE 
Being a "ratio method", it works for TOA radiance as well
4SM only uses the satellite image: no atmospheric correction or field data required
Yields both retrieved depth and water column corrected radiance ready for bottom typing
 
      
      

It works! How about you? 
Starting in 2009 for a project in Tanzania, I got paid good money for several demanding projects using Landsat   
      
   

Users of Stumpf et al's method, please be advised: 
On the cost of dispensing with water volume reflectance

 

lyzenga maritorena water column correction multispectral hyperspectral shallow bathymetry retrieval passive optical bathymetry shallow depth retrieval satellite image satellite bathymetry satellite derived bathymetry satellite bathymetry accuracy bathymetry mapping software bathymetric mapping software marine remote sensing bottom typing bottom type classification habitat mapping  reflectance  glint correction  coastal managment  diffuse attenuation coefficient  empirical casi  landsat  etm  tm  world view 2  wv2, ikonos  hyperion  oli quickbird ali panchromatic pansharpened  


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