4SM on OLI at Caicos Bank, Bahamas

Optical calibration, bathymetry, water column correction and bottom typing of shallow marine areas, using passive remote sensing imageries
Bathymetry and water column correction

LANDSAT 8 OLIP
at Caicos Bank, Bahamas
4018*4149, 30 m pixel size, UTM zone 18, downloaded from USGS
Image courtesy of the U.S. Geological Survey

Using the Panchromatic band for water column correction
to derive water depth and spectral bottom signature:

Landsat 8 OLIP bandset used for this work
Purple_1, Blue_2, Green_3, PAN_4, Red_5, NIR_6 and SWIR1_7

Please refer to Bora Bora and Sanaa for use of the PANchromatic band for water column correction

scene LC80090452014056LGN00, February 25th 2014

Work done august 2016
home

DTM seatruth RMSE=0.61 m

DTM depth - 4SM depth
Htide=1.2m tide correction applied to DTM depth
see legend

Seatruth regression
Tide correction applied to DTM depths: 1.2 m

Data and Deglinting

TOA TCC: raw image
logarithmic enhancement

BOA TCC deglinted image
linear enhancement

Optical calibration, optimized
16U data are scaled to allow for comfortable screen display

Calibration diagram for the whole scene for bands Blue, Green, Red and NIR K_BLUE/K_GREEN=0.51 => Jerlov water type OIB+0.37	Calibration diagram for the whole scene for bands Blue, PAN, RED and NIR
Reflectance (0-1) of the path radiance Ra for this scene 0.102 0.077 0.044 0.039 0.025 0.011 0.002	Reflectance (0-1) of the water volume Rw for this scene 0.019 0.016 0.002 0.001 0.0 0.0 0.0

Now ready for Modeling

SAM classified image This is end February 2014 see legend for SAM	ImageB: average bottom brightness This is end february 2014
BOA TCC water column corrected	Retrieved depth see legend