slcOLI_20161214

scene LC80340432016349LGN00, December 12th 2016
DATE_ACQUIRED = 2016-12-14
SCENE_CENTER_TIME = "17:48:08.0454640Z"

Work done december 2016

15 m GSD by 4SM. No PANsharpening

Ground truth
limited to Isla Espiritu Santo and San Lorenzo Channel
Seatruth DTM is Combined Depth raster

Regression December 14th 2016 vs DTM tide correction applied: Htide=0.80m Lsw_PAN might be reduced a wee bit in order to reduce over-estimation of depths in the 15-25 m range	ZDTM - Z4SM DTM - December 14th tide correction applied: Htide=0.80m RED: this vast area of underestimated depths signals the westward flow of slightly more turbid waters: this corresponds to brown-green areas in image B see legend
tide correction applied: Htide=0.80m 0-10 m: depths are correct 10-20 m: depths are under-estimated 20-25 m: depths are over-estimated	DTM this is Combined Depth 15 m GSD

Data and deglinting
Complex hydrology:
Blooming Sea of Cortez is pouring westwards into Bay of La Paz

TOA TCC: raw image logarithmic enhancement	BOA TCC deglinted, histeq enhancement complex hydrology
Glint regressions	Clearly suggests flow of waters from SE Sea of Cortez through the channel, into the Bay of La Paz. ROI is where deep water radiance is sampled
Look at those lineaments in the PAN image are they real, scoured by currents? do they signal microtopography?

Optical calibration
for the whole image

Calibration diagram
for bands Blue, Green, Red and NIR
Water type OII+0.7

Calibration diagram
for bands Blue, PAN, Red and NIR

Type10 WCC signature
is promoted to the local reference for SAM
see its location at Bahia San Gabriel

It represents the brightest bottom substrate at shallow depth around
It is expected and assumed to be free of significant chrophyll pigments
Calibration of the Soil Line is optimized so as to obtain WCC reflectance at 200 in all blue-green bands for type10 WCC signature:
- this is done by tweaking LsM
- it yields SA_ref=(0.199+0.257)/(2*0.366)
So, SA_reference=0.62 for this image,
- and we know that SA_CoralSand=0.78
So, upon modeling in 4SM, all SA values
- are scaled as SA=SA*0.75/0.62
- then rescaled as SA=100*SA
to be displayed using SAM2 color table

SAM: Type10 signature

Calibration of the Soil Line is optimized so as to obtain WCC reflectance at 200 in all blue-green bands:
- this yields SA_reference=0.62 for this image
We know that SA_CoralSand=0.78

So, upon modeling, all SA values are offset as follows: SA=SA*0.75/0.62
to be displayed using SAM2 color table

SAM: remember

SAM has nothing to do with brightness
SAM is only concerned to map how green stands out in the WCC bottom signature,
- whatever the brightness

SAM and Soil Line

dull signatures=Soil Line: so, all water column corrected pixels which do not exhibit an excess -or a deficit- of Green reflectance belong to the family of the Soil Line, from dark to bright
- they shall map in the 0.7-0.8 class of the SAM2 color table
contrasted signatures:
- High Green signatures: shall map in the 0.0-0.7 classes of the SAM2 color table
- Low Green signatures: shall map in the 0.8-1.3 classes of the SAM2 color table

Ready for modeling

BOA CC WCC normalized
CoefNorm=2.5
BGR color composite:

Blue=Coastal band
Green=Green band
Red=Blue band

Retrieved depth
see legend

Profile Black

Profile Black
Htide=0.80m

Location of Profile Black
backdrop is Z4SM

WEST sections A and B
EAST sections C and D

Bottom typing

SAM classified image see legend for image SAM	Average bottom brightness dark green-brown: looks like the whole channel is affected by more turbid waters flowing westwards see legend for image B
NDRblues200 see legend for NDRblues

Download from my GoogleDrive
slcOLI_20161214_15mresults.zip 52 MB
Channel Descriptor file="slcOLI_20161214_15mresults.pix"; 1 U8 SAM bottom typing----------------------------- 2 U8 image B average bottom brightness (0-200)----- 3 U8 image Z in decimeters------------------------- 4 U8 WCC reflectance (0-250) at 440.0 nm----------- 5 U8 WCC reflectance (0-250) at 480.0 nm----------- 6 U8 WCC reflectance (0-250) at 560.0 nm----------- 7 U8 WCC reflectance (0-250) at 590.0 nm----------- 8 U8 WCC reflectance (0-250) at 655.0 nm----------- 9 U8 WCCnormalized (0-250) at 440.0 nm>B----------- 10 U8 WCCnormalized (0-250) at 560.0 nm>G----------- 11 U8 WCCnormalized (0-250) at 480.0 nm>R----------- 12 S16 Z4SM in centimeters-------------------------- 13 S16 ZDTM in centimeters-------------------------- 14 S16 ZDTM-Z4SM in centimeters--------------------- plus profile_black_PlotZB.eps profile_fabio1_PlotZB.eps?