trws-Mask3-Calibrate

Activity
Calibrate and Model under Mask_3

LINE_6

Please, append a copy of #LINE_6 into your script,
then follow the instructions, step by step

MapBPL color composite
Syntax_Extract

Map BPL under Mask 4	Map BPL under Mask 3
Most BPL pixels are located at a well protected shallow beach	Most BPL pixels are located in/around shallow steams of oceanic waters entering the lagoon from the reef

Bulge and saturation:
very shallow bottoms are much brighter

Calibration under Mask_3

<<==The large bulge in Ls1 vs Ls2 diagram
points to very shallow areas which are
up to 1.35 times brighter than under mask_4.

This bulge represents the saturated areas
that we already noted.

This obviously happens
where very clear oceanic waters flow
from the reef into the lagoon,
through the hoas.
This might signal precipitation
of calcium carbonate particles
in very warm and shallow waters.

Particulate inorganic carbon (PIC)

"Lagoon water is rather turbid in the south lagoon, but this is mainly due to high PIC concentrations. What may appear to a casual observer to be polluted water is merely water in which is suspended large quantities of small particles of calcium carbonate generated by normal processes."

This time again,
the Ghost pixels confirm
that this bulge is not an artifact of sort.

Bad fit / Good fit
Kgreen/Kred changes from 0.29 to 0.46

Calibration under Mask_3 KIKJ=0.29: Jerlov water type Oceanic II This area exhibits a ratio KIKJ much higher than 0.29. Waters under Mask_3 are distinctly less clear than under Mask_4.	Calibration under Mask_3 KIKJ=0.46: Jerlov water type Coastal 1+0.3 The ratio KIKJ=0.46 suits very well this area.
Waters under Mask_4 are under the influence of Oceanic waters.	Waters under Mask_3 are less clear: South-East lagoon waters are confined.

Comparing two models
LINE 5 by Mask_4 and **LINE 6 by Mask_3**
A compromise between the two models would possibly be useful
Computed depth Zcm by LINE 5 by LINE 6 Point Querry 14.68 m 11.73 m	Bottom brightness B by LINE 5 by LINE 6

Activity
Extract and plot bi-dimensional histograms for Calibration
Learn about using the -Recode/... argument

LINE 7

LINE 7: Extract and plot bidim histograms

BiDimensional histograms
For the optical calibration, much insight can be gained by studying bidim histograms,
as they reflect all aspects of the various processes which affect spectral radiance,

through the atmosphere,
at the water surface,
through the water column,
and at the shallow bottom.

Please append #LINE_7... to your script, and follow the instructions

BiDimensional histograms over glint area	BiDimensional histograms over glint/cloud/shadow area
mSE=10 under black areas Using a mask_10 shapefile, the -Recode/... argument recodes all marine pixels to 10 in mask mSE	BiDim histogram under black areas recoded to mSE=10