Upload
doankiet
View
232
Download
0
Embed Size (px)
Citation preview
Analysis of the Sea Surface Scattering Analysis of the Sea Surface Scattering
With and Without Surface SlicksWith and Without Surface Slicks
(1)F.Nunziata, (2)P.Sobieski, (1)M.Migliaccio(1)Università degli Studi di Napoli “Parthenope”, Dipartimento per le Tecnologie
Napoli, Italy. [email protected]
(2)Université Catholique de Louvain, Laboratoire de Télécommunications
LouvainlaNeuve, Belgium. [email protected]
Physically radar oil spill observation is possible since an oil slick generates a low backscatter area
MotivationMotivation
Distinguishing oil slicks from other dark areas is not easy
MotivationMotivation
• Oil slicks.Oil slicks.• Biogenic slicks.• Low wind areas.• Rain cells.• Currents.• Internal waves.
To ensure an effective oil spill detection a physically based contrast model is needed
MotivationMotivation
C= f
o
co
Slickcovered NRCS
MotivationMotivation
slickfree NRCSslickfree NRCS
damping modeldamping modelenv. conditionsenv. conditions
slickcovered NRCS
Slickfree NRCS
ModelModel
In literature the SPM is commonly employed
In this study the twoscale BPM is employed, under low to moderate wind conditions
rt
o=4
k 4 cos4 θ∣αrt∣2 W K
rt
o=rt0
o rt1
o
Slickfree NRCS: twoscale BPM
ModelModel
rt0
o =
cos4 sp
∣Rrt,eff θ loc ∣
2
Tsl sp
,sp
rt10 =
k 2
4 z/ k
2∬∣H
rt K x
' ,Ky
' ∣2
R K x
,Ky T sl K x
' ,Ky
' dKxdK
y
Slickcovered NRCS
ModelModel
Marangoni
Reduced u*
slope pdfslope pdf
0 skewness
Slickcovered NRCS
Rehological
ExperimentsExperimentsCband SIRC/XSAR data in which an OLA is present
29.3° 29.7°
• Measured vs predicted contrast
ExperimentsExperimentsCband SIRC/XSAR data in which an OLA is present
29.3° 29.7°
• SPM vs twoscale BPM contrast
ExperimentsExperimentsLband SIRC/XSAR data in which an OLA is present
29.3° 29.7°
• Measured vs predicted contrast
ConclusionsConclusions
• A contrast model based on the twoscale BPM has been developed.
• The surface slick is supposed to affect both the sea surface spectrum and the slope pdf.
• First experiments show a good agreement between the predicted BPM contrast and the measured one both at C and Lband.
• The damping properties of the surface slick have been described by using the simple Marangoni model.
• No polarization and azimuthal dependence have been experienced.