In situ optical variability and relationships in the Santa Barbara Channel: Implications for remote sensing

Ocean Physics Laboratory, University of California Santa Barbara, Goleta 93117, USA.
Applied Optics (Impact Factor: 1.78). 06/2006; 45(15):3593-604. DOI: 10.1364/AO.45.003593
Source: PubMed


Relationships and variability of bio-optical properties in coastal waters are investigated. Optical proxies indicate that these coastal waters are optically complex and highly variable and are categorized as follows: (1) relatively clear and dominated by high index of refraction, biogenic particles, (2) more turbid, consisting of mostly inorganic particles and little phytoplankton, (3) extremely turbid with high concentrations of inorganic particles, and (4) more turbid and dominated by biogenic particles. We present a method, alternative to traditional remote-sensing algorithms, of classifying coastal waters [the Spectral Angle Mapper (SAM)] and utilize the SAM to successfully isolate plume conditions in time series of downwelling irradiance and total absorption coefficient. We conclude with a discussion of the use of the SAM for coastal management operations.

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    • "The overall mean backscattering ratio ~ b bp at 532 nm was 0 . 02 6 0 . 007 . The range of ~ b bp ( 0 . 005 – 0 . 05 ) cov - ered nearly the whole range observed in previous studies performed in different coastal , oceanic , and lake environments [ Twardowski et al . , 2001 ; Chang et al . , 2006 ; Boss et al . , 2004 ; McKee and Cunningham , 2006 ; Loisel et al . , 2007 ; Whitmire et al . , 2007 ; Snyder et al . , 2008 ; Sun et al . , 2009 ] . Figure 5c shows that ~ b bp ð532Þ increased with depth with the highest values often observed near the bottom . This is consistent with the observations by Chami et al . [ 2005 ] but the "
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    • "inst the γ cp and PSD slopes respectively as shown in Fig . 6 . Data in the mixed layer and at the chlmax depth are selected to compare the vertical difference . bp b ~ varies between 0 . 005 and 0 . 032 , which is in good agreement with previous studies performed in different coastal , oceanic , and limnic environments ( Twardowski et al . 2001 , Chang et al . 2004 , Boss et al . 2004 , McKee and Cunningham , 2006 , Loisel et al . 2007 , Whitmire et al . 2007 , Snyder et al . 2008 , Sun et al . 2009 ) . However , bp b ~ varies in a smaller range in the mixed layer [ 0 . 004 – 0 . 022 ] compared to that at the chlmax depth , [ 0 . 008 – 0 . 032 ] . Most of the bulk refractive index p n estimated in"
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