Determination of biogeochemical properties of marine particles using above water measurements of the degree of polarization at the Brewster angle

David J.C. McKee, Malik Chami

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Retrieval of biogeochemical parameters from remotely sensed data in optically complex waters such as those found in coastal zones is a challenging task due to the effects of various water constituents (biogenic, nonalgal and inorganic particles, dissolved matter) on the radiation exiting the ocean. Since scattering by molecules, aerosols, hydrosols and reflection at the sea surface introduce and modify the polarization state of light, the polarized upward radiation contains embedded information about the intrinsic nature of aerosols and suspended matter in the ocean. In this study, shipborne above water angularly resolved visible/near infrared multiband measurements of the degree of polarization are analysed against their corresponding in-situ biogeochemically characterized water samples for the first time. Water samples and radiometric data were collected in the English Channel along an inshore-offshore transect. Angular variations in the degree of polarization P are found to be consistent with theory. Maximum values of P are observed near the Brewster viewing angle in the specular direction. Variations in the degree of polarization at the Brewster angle (PB) with water content revealed that the suspended particulate matter, which is mainly composed of inorganic particles during the experiment, contributes to depolarise the skylight reflection, thus reducing PB. An empirical polarization-based approach is proposed to determine biogeochemical properties of the particles. The concentration of inorganic particles can be estimated using PB to within ±13% based on the dataset used. Larger sets of polarized measurements are recommended to corroborate the tendency observed in this study.
LanguageEnglish
Pages9494-9509
Number of pages15
JournalOptics Express
Volume15
Issue number15
DOIs
Publication statusPublished - 17 Jul 2007

Fingerprint

Brewster angle
polarization
water
aerosols
oceans
English Channel
polarized radiation
particulates
moisture content
retrieval
tendencies
radiation
scattering
molecules

Keywords

  • biogeochemical properties
  • marine particles
  • polarization
  • Brewster angle

Cite this

@article{22cc26fa3c0747339516b4f896032402,
title = "Determination of biogeochemical properties of marine particles using above water measurements of the degree of polarization at the Brewster angle",
abstract = "Retrieval of biogeochemical parameters from remotely sensed data in optically complex waters such as those found in coastal zones is a challenging task due to the effects of various water constituents (biogenic, nonalgal and inorganic particles, dissolved matter) on the radiation exiting the ocean. Since scattering by molecules, aerosols, hydrosols and reflection at the sea surface introduce and modify the polarization state of light, the polarized upward radiation contains embedded information about the intrinsic nature of aerosols and suspended matter in the ocean. In this study, shipborne above water angularly resolved visible/near infrared multiband measurements of the degree of polarization are analysed against their corresponding in-situ biogeochemically characterized water samples for the first time. Water samples and radiometric data were collected in the English Channel along an inshore-offshore transect. Angular variations in the degree of polarization P are found to be consistent with theory. Maximum values of P are observed near the Brewster viewing angle in the specular direction. Variations in the degree of polarization at the Brewster angle (PB) with water content revealed that the suspended particulate matter, which is mainly composed of inorganic particles during the experiment, contributes to depolarise the skylight reflection, thus reducing PB. An empirical polarization-based approach is proposed to determine biogeochemical properties of the particles. The concentration of inorganic particles can be estimated using PB to within ±13{\%} based on the dataset used. Larger sets of polarized measurements are recommended to corroborate the tendency observed in this study.",
keywords = "biogeochemical properties, marine particles, polarization, Brewster angle",
author = "McKee, {David J.C.} and Malik Chami",
year = "2007",
month = "7",
day = "17",
doi = "10.1364/OE.15.009494",
language = "English",
volume = "15",
pages = "9494--9509",
journal = "Optics Express",
issn = "1094-4087",
publisher = "Optical Society of America",
number = "15",

}

Determination of biogeochemical properties of marine particles using above water measurements of the degree of polarization at the Brewster angle. / McKee, David J.C.; Chami, Malik.

In: Optics Express, Vol. 15, No. 15, 17.07.2007, p. 9494-9509.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Determination of biogeochemical properties of marine particles using above water measurements of the degree of polarization at the Brewster angle

AU - McKee, David J.C.

AU - Chami, Malik

PY - 2007/7/17

Y1 - 2007/7/17

N2 - Retrieval of biogeochemical parameters from remotely sensed data in optically complex waters such as those found in coastal zones is a challenging task due to the effects of various water constituents (biogenic, nonalgal and inorganic particles, dissolved matter) on the radiation exiting the ocean. Since scattering by molecules, aerosols, hydrosols and reflection at the sea surface introduce and modify the polarization state of light, the polarized upward radiation contains embedded information about the intrinsic nature of aerosols and suspended matter in the ocean. In this study, shipborne above water angularly resolved visible/near infrared multiband measurements of the degree of polarization are analysed against their corresponding in-situ biogeochemically characterized water samples for the first time. Water samples and radiometric data were collected in the English Channel along an inshore-offshore transect. Angular variations in the degree of polarization P are found to be consistent with theory. Maximum values of P are observed near the Brewster viewing angle in the specular direction. Variations in the degree of polarization at the Brewster angle (PB) with water content revealed that the suspended particulate matter, which is mainly composed of inorganic particles during the experiment, contributes to depolarise the skylight reflection, thus reducing PB. An empirical polarization-based approach is proposed to determine biogeochemical properties of the particles. The concentration of inorganic particles can be estimated using PB to within ±13% based on the dataset used. Larger sets of polarized measurements are recommended to corroborate the tendency observed in this study.

AB - Retrieval of biogeochemical parameters from remotely sensed data in optically complex waters such as those found in coastal zones is a challenging task due to the effects of various water constituents (biogenic, nonalgal and inorganic particles, dissolved matter) on the radiation exiting the ocean. Since scattering by molecules, aerosols, hydrosols and reflection at the sea surface introduce and modify the polarization state of light, the polarized upward radiation contains embedded information about the intrinsic nature of aerosols and suspended matter in the ocean. In this study, shipborne above water angularly resolved visible/near infrared multiband measurements of the degree of polarization are analysed against their corresponding in-situ biogeochemically characterized water samples for the first time. Water samples and radiometric data were collected in the English Channel along an inshore-offshore transect. Angular variations in the degree of polarization P are found to be consistent with theory. Maximum values of P are observed near the Brewster viewing angle in the specular direction. Variations in the degree of polarization at the Brewster angle (PB) with water content revealed that the suspended particulate matter, which is mainly composed of inorganic particles during the experiment, contributes to depolarise the skylight reflection, thus reducing PB. An empirical polarization-based approach is proposed to determine biogeochemical properties of the particles. The concentration of inorganic particles can be estimated using PB to within ±13% based on the dataset used. Larger sets of polarized measurements are recommended to corroborate the tendency observed in this study.

KW - biogeochemical properties

KW - marine particles

KW - polarization

KW - Brewster angle

U2 - 10.1364/OE.15.009494

DO - 10.1364/OE.15.009494

M3 - Article

VL - 15

SP - 9494

EP - 9509

JO - Optics Express

T2 - Optics Express

JF - Optics Express

SN - 1094-4087

IS - 15

ER -