Abstract

Seawater inherent optical properties (IOPs) are key parameters in a wide range of applications in environmental studies and oceanographic research. In particular, the absorption coefficient (a) is the typical IOP used to obtain the concentration of chlorophyll-a in the water—a critical parameter in biological oceanography studies and the backscattering coefficient (bb) is used as a measure of turbidity. In this study, we test a novel instrument concept designed to obtain both the absorption and backscattering coefficients. The instrument would emit a collimated monochromatic light beam into the water retrieving the backscattered light intensity as a function of distance from the center of illumination. We use Monte Carlo modeling of light propagation to create an inversion algorithm that translates the signal from such an instrument into values of a and bb. Our results, based on simulations spanning the bulk of natural values of seawater IOP combinations, indicate that a 6.2cm diameter instrument with a radial resolution of 1cm would be capable of predicting bb within less than 13.4% relative difference and a within less than 57% relative difference (for 90% of the inverted a values, the relative errors fall below 29.7%). Additionally, these errors could be further reduced by constraining the inversion algorithm with information from concurrent measurements of other IOPs. Such a compact and relatively simple device could have multiple applications for in situ optical measurements, including a and bb retrievals from instrumentation mounted on autonomous underwater vehicles. Furthermore, the same methodology could possibly be used for an out-of-water sensor.

© 2011 Optical Society of America

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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  8. Absorption measurements have been performed using ac-9+ spectrophotometers mounted on very large AUVs . However, because of their size (requiring large vessels for deployment and implying short mission durations), these platforms are not applicable to long-term routine IOP monitoring.
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  27. M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  31. N. J. Jerlov, “Marine optics,” Elsevier Oceanogr. Ser. 14, i–xiii, 1–231 (1976).
    [CrossRef]

2010

2009

2008

T. D. Dickey, E. C. Itsweire, M. A. Moline, and M. J. Perry, “Introduction to the limnology and oceanography: special issue on autonomous and Lagrangian platforms and sensors (ALPS),” Limnol. Oceanogr. 53, 2057–2061 (2008).
[CrossRef]

C. S. Roesler and E. Boss, “In situ measurement of the inherent optical properties (IOPs) and potential for harmful algal bloom detection and coastal ecosystem observations,” in Real-Time Coastal Observing Systems for Ecosystem Dynamics and Harmful Algal Bloom (UNESCO, 2008), pp. 153–206.

2007

C. Giardino, V. E. Brando, A. G. Dekker, N. Strombeck, and G. Candiani, “Assessment of water quality in lake Garda (Italy) using Hyperion,” Remote Sens. Environ. 109, 183–195(2007).
[CrossRef]

H. Loisel, X. Mériaux, J.-F. Berthon, and A. Poteau, “Investigation of the optical backscattering to scattering ratio of marine particles in relation with their biogeochemical composition in the eastern English Channel and southern North Sea,” Limnol. Oceanogr. 52, 739–752 (2007).
[CrossRef]

A. L. Whitmire, E. Boss, T. J. Cowles, and W. S. Pegau, “Spectral variability of the particulate backscattering ratio,” Opt. Express 15, 7019–7031 (2007).
[CrossRef] [PubMed]

2006

T. Dickey, M. Lewis, and G. Chang, “Optical oceanography: recent advances and future directions using global remote sensing and in situ observations,” Rev. Geophys. 44, RG1001(2006).
[CrossRef]

Z. Lee, “Remote sensing of inherent optical properties: fundamentals, tests of algorithms, and applications,” Tech. Rep. 5 (International Ocean Colour Coordinating Group, 2006).

2005

2004

R. A. Leathers, T. V. Downes, C. O. Davis, and C. D. Mobley, “Monte Carlo radiative transfer simulations for ocean optics: a practical guide,” Memorandum report A426624 (Naval Research Laboratory, 2004).

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

2003

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
[CrossRef]

A. Cunningham, D. McKee, S. Craig, G. Tarran, and C. Widdicombe, “Fine-scale variability in phytoplankton community structure and inherent optical properties measured from an autonomous underwater vehicle,” J. Mar. Syst. 43, 51–59 (2003).
[CrossRef]

D. L. Rudnick and M. J. Perry, “ALPS: Autonomous and Lagrangian Platforms and Sensors,” Workshop report, www.geo-prose.com/ALPS (Geo Prose, 2003).

2002

2001

E. Boss and W. S. Pegau, “Relationship of light scattering at an angle in the backward direction to the backscattering coefficient,” Appl. Opt. 40, 5503–5507 (2001).
[CrossRef]

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

1999

G. R. Fournier and M. Jonasz, “Computer-based underwater imaging analysis,” in Conference on Airborne and In-Water Underwater Imaging (SPIE, 1999), Vol.  3761, pp. 62–70.

1998

K. Suzuki, M. Kishino, K. Sasaoka, S. Saitoh, and T. Saino, “Chlorophyll-specific absorption coefficients and pigments of phytoplankton off Sanriku, northwestern north Pacific,” J. Oceanogr. 54, 517–526 (1998).
[CrossRef]

A. H. Barnard, W. S. Pegau, and J. R. V. Zaneveld, “Global relationships of the inherent optical properties of the oceans,” J. Geophys. Res. 103, 24955–24968 (1998).
[CrossRef]

1997

1994

C. D. Mobley, Light and Water: Radiative Transfer in Natural Waters, 1st ed. (Academic, 1994).

1992

J. R. V. Zaneveld, J. C. Kitchen, A. Bricaud, and C. C. Moore, “Analysis of in-situ spectral absorption meter data,” Proc. SPIE 1750, 187–200 (1992).
[CrossRef]

1983

J. Downing, “An optical instrument for monitoring suspended particulates in ocean and laboratory,” in Proceedings OCEANS ’83 (IEEE, 1983), pp. 199–202.
[CrossRef]

1976

N. J. Jerlov, “Marine optics,” Elsevier Oceanogr. Ser. 14, i–xiii, 1–231 (1976).
[CrossRef]

Babin, M.

E. Leymarie, D. Doxaran, and M. Babin, “Uncertainties associated to measurements of inherent optical properties in natural waters,” Appl. Opt. 49, 5415–5436 (2010).
[CrossRef] [PubMed]

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
[CrossRef]

Barantange, F.

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

Barnard, A. H.

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

A. H. Barnard, W. S. Pegau, and J. R. V. Zaneveld, “Global relationships of the inherent optical properties of the oceans,” J. Geophys. Res. 103, 24955–24968 (1998).
[CrossRef]

Behrenfeld, M. J.

Berthon, J.-F.

H. Loisel, X. Mériaux, J.-F. Berthon, and A. Poteau, “Investigation of the optical backscattering to scattering ratio of marine particles in relation with their biogeochemical composition in the eastern English Channel and southern North Sea,” Limnol. Oceanogr. 52, 739–752 (2007).
[CrossRef]

Boss, E.

T. K. Westberry, G. Dall’Olmo, E. Boss, M. J. Behrenfeld, and T. Moutin, “Coherence of particulate beam attenuation and backscattering coefficients in diverse open ocean environments,” Opt. Express 18, 15419–15425 (2010).
[CrossRef] [PubMed]

C. S. Roesler and E. Boss, “In situ measurement of the inherent optical properties (IOPs) and potential for harmful algal bloom detection and coastal ecosystem observations,” in Real-Time Coastal Observing Systems for Ecosystem Dynamics and Harmful Algal Bloom (UNESCO, 2008), pp. 153–206.

A. L. Whitmire, E. Boss, T. J. Cowles, and W. S. Pegau, “Spectral variability of the particulate backscattering ratio,” Opt. Express 15, 7019–7031 (2007).
[CrossRef] [PubMed]

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

C. D. Mobley, L. K. Sundman, and E. Boss, “Phase function effects on oceanic light fields,” Appl. Opt. 41, 1035–1050(2002).
[CrossRef] [PubMed]

E. Boss and W. S. Pegau, “Relationship of light scattering at an angle in the backward direction to the backscattering coefficient,” Appl. Opt. 40, 5503–5507 (2001).
[CrossRef]

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

Boyd, T. J.

Brando, V. E.

C. Giardino, V. E. Brando, A. G. Dekker, N. Strombeck, and G. Candiani, “Assessment of water quality in lake Garda (Italy) using Hyperion,” Remote Sens. Environ. 109, 183–195(2007).
[CrossRef]

Bricaud, A.

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

J. R. V. Zaneveld, J. C. Kitchen, A. Bricaud, and C. C. Moore, “Analysis of in-situ spectral absorption meter data,” Proc. SPIE 1750, 187–200 (1992).
[CrossRef]

Brown, I.

Cahalan, R. F.

R. F. Cahalan, M. McGill, J. Kolasinski, T. Várnai, and K. Yetzer, “THOR—Cloud thickness from offbeam lidar returns,” J. Atmos. Ocean. Technol. 22, 605–627 (2005).
[CrossRef]

Calzado, V. S.

Candiani, G.

C. Giardino, V. E. Brando, A. G. Dekker, N. Strombeck, and G. Candiani, “Assessment of water quality in lake Garda (Italy) using Hyperion,” Remote Sens. Environ. 109, 183–195(2007).
[CrossRef]

Chami, M.

Chang, G.

T. Dickey, M. Lewis, and G. Chang, “Optical oceanography: recent advances and future directions using global remote sensing and in situ observations,” Rev. Geophys. 44, RG1001(2006).
[CrossRef]

Claustre, H.

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

Cowles, T. J.

Craig, S.

A. Cunningham, D. McKee, S. Craig, G. Tarran, and C. Widdicombe, “Fine-scale variability in phytoplankton community structure and inherent optical properties measured from an autonomous underwater vehicle,” J. Mar. Syst. 43, 51–59 (2003).
[CrossRef]

Cunningham, A.

D. McKee, M. Chami, I. Brown, V. S. Calzado, D. Doxaran, and A. Cunningham, “Role of measurement uncertainties in observed variability in the spectral backscattering ratio: a case study in mineral-rich coastal waters,” Appl. Opt. 48, 4663–4675 (2009).
[CrossRef] [PubMed]

A. Cunningham, D. McKee, S. Craig, G. Tarran, and C. Widdicombe, “Fine-scale variability in phytoplankton community structure and inherent optical properties measured from an autonomous underwater vehicle,” J. Mar. Syst. 43, 51–59 (2003).
[CrossRef]

Dall’Olmo, G.

Dana, D. R.

Davis, C. O.

R. A. Leathers, T. V. Downes, C. O. Davis, and C. D. Mobley, “Monte Carlo radiative transfer simulations for ocean optics: a practical guide,” Memorandum report A426624 (Naval Research Laboratory, 2004).

Dekker, A. G.

C. Giardino, V. E. Brando, A. G. Dekker, N. Strombeck, and G. Candiani, “Assessment of water quality in lake Garda (Italy) using Hyperion,” Remote Sens. Environ. 109, 183–195(2007).
[CrossRef]

Dickey, T.

T. Dickey, M. Lewis, and G. Chang, “Optical oceanography: recent advances and future directions using global remote sensing and in situ observations,” Rev. Geophys. 44, RG1001(2006).
[CrossRef]

Dickey, T. D.

T. D. Dickey, E. C. Itsweire, M. A. Moline, and M. J. Perry, “Introduction to the limnology and oceanography: special issue on autonomous and Lagrangian platforms and sensors (ALPS),” Limnol. Oceanogr. 53, 2057–2061 (2008).
[CrossRef]

Donaghay, P. L.

Downes, T. V.

R. A. Leathers, T. V. Downes, C. O. Davis, and C. D. Mobley, “Monte Carlo radiative transfer simulations for ocean optics: a practical guide,” Memorandum report A426624 (Naval Research Laboratory, 2004).

Downing, J.

J. Downing, “An optical instrument for monitoring suspended particulates in ocean and laboratory,” in Proceedings OCEANS ’83 (IEEE, 1983), pp. 199–202.
[CrossRef]

Doxaran, D.

Fell, F.

M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
[CrossRef]

Ferrari, G. M.

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

Fournier, G. R.

G. R. Fournier and M. Jonasz, “Computer-based underwater imaging analysis,” in Conference on Airborne and In-Water Underwater Imaging (SPIE, 1999), Vol.  3761, pp. 62–70.

Fournier-Sicre, V.

M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
[CrossRef]

Freeman, S. A.

Giardino, C.

C. Giardino, V. E. Brando, A. G. Dekker, N. Strombeck, and G. Candiani, “Assessment of water quality in lake Garda (Italy) using Hyperion,” Remote Sens. Environ. 109, 183–195(2007).
[CrossRef]

Hoepffner, N.

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

Itsweire, E. C.

T. D. Dickey, E. C. Itsweire, M. A. Moline, and M. J. Perry, “Introduction to the limnology and oceanography: special issue on autonomous and Lagrangian platforms and sensors (ALPS),” Limnol. Oceanogr. 53, 2057–2061 (2008).
[CrossRef]

Jerlov, N. J.

N. J. Jerlov, “Marine optics,” Elsevier Oceanogr. Ser. 14, i–xiii, 1–231 (1976).
[CrossRef]

Jonasz, M.

G. R. Fournier and M. Jonasz, “Computer-based underwater imaging analysis,” in Conference on Airborne and In-Water Underwater Imaging (SPIE, 1999), Vol.  3761, pp. 62–70.

Kishino, M.

K. Suzuki, M. Kishino, K. Sasaoka, S. Saitoh, and T. Saino, “Chlorophyll-specific absorption coefficients and pigments of phytoplankton off Sanriku, northwestern north Pacific,” J. Oceanogr. 54, 517–526 (1998).
[CrossRef]

Kitchen, J. C.

J. R. V. Zaneveld, J. C. Kitchen, A. Bricaud, and C. C. Moore, “Analysis of in-situ spectral absorption meter data,” Proc. SPIE 1750, 187–200 (1992).
[CrossRef]

Kolasinski, J.

R. F. Cahalan, M. McGill, J. Kolasinski, T. Várnai, and K. Yetzer, “THOR—Cloud thickness from offbeam lidar returns,” J. Atmos. Ocean. Technol. 22, 605–627 (2005).
[CrossRef]

Korotaev, G.

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

Leathers, R. A.

R. A. Leathers, T. V. Downes, C. O. Davis, and C. D. Mobley, “Monte Carlo radiative transfer simulations for ocean optics: a practical guide,” Memorandum report A426624 (Naval Research Laboratory, 2004).

Lee, M.

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

Lee, Z.

Z. Lee, “Remote sensing of inherent optical properties: fundamentals, tests of algorithms, and applications,” Tech. Rep. 5 (International Ocean Colour Coordinating Group, 2006).

Lewis, M.

T. Dickey, M. Lewis, and G. Chang, “Optical oceanography: recent advances and future directions using global remote sensing and in situ observations,” Rev. Geophys. 44, RG1001(2006).
[CrossRef]

Leymarie, E.

Loisel, H.

H. Loisel, X. Mériaux, J.-F. Berthon, and A. Poteau, “Investigation of the optical backscattering to scattering ratio of marine particles in relation with their biogeochemical composition in the eastern English Channel and southern North Sea,” Limnol. Oceanogr. 52, 739–752 (2007).
[CrossRef]

Macdonald, J. B.

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

Maffione, R.

McGill, M.

R. F. Cahalan, M. McGill, J. Kolasinski, T. Várnai, and K. Yetzer, “THOR—Cloud thickness from offbeam lidar returns,” J. Atmos. Ocean. Technol. 22, 605–627 (2005).
[CrossRef]

McKee, D.

D. McKee, M. Chami, I. Brown, V. S. Calzado, D. Doxaran, and A. Cunningham, “Role of measurement uncertainties in observed variability in the spectral backscattering ratio: a case study in mineral-rich coastal waters,” Appl. Opt. 48, 4663–4675 (2009).
[CrossRef] [PubMed]

A. Cunningham, D. McKee, S. Craig, G. Tarran, and C. Widdicombe, “Fine-scale variability in phytoplankton community structure and inherent optical properties measured from an autonomous underwater vehicle,” J. Mar. Syst. 43, 51–59 (2003).
[CrossRef]

Mériaux, X.

H. Loisel, X. Mériaux, J.-F. Berthon, and A. Poteau, “Investigation of the optical backscattering to scattering ratio of marine particles in relation with their biogeochemical composition in the eastern English Channel and southern North Sea,” Limnol. Oceanogr. 52, 739–752 (2007).
[CrossRef]

Mobley, C. D.

R. A. Leathers, T. V. Downes, C. O. Davis, and C. D. Mobley, “Monte Carlo radiative transfer simulations for ocean optics: a practical guide,” Memorandum report A426624 (Naval Research Laboratory, 2004).

C. D. Mobley, L. K. Sundman, and E. Boss, “Phase function effects on oceanic light fields,” Appl. Opt. 41, 1035–1050(2002).
[CrossRef] [PubMed]

C. D. Mobley, Light and Water: Radiative Transfer in Natural Waters, 1st ed. (Academic, 1994).

Moline, M. A.

T. D. Dickey, E. C. Itsweire, M. A. Moline, and M. J. Perry, “Introduction to the limnology and oceanography: special issue on autonomous and Lagrangian platforms and sensors (ALPS),” Limnol. Oceanogr. 53, 2057–2061 (2008).
[CrossRef]

Moore, C. C.

J. R. V. Zaneveld, J. C. Kitchen, A. Bricaud, and C. C. Moore, “Analysis of in-situ spectral absorption meter data,” Proc. SPIE 1750, 187–200 (1992).
[CrossRef]

Morel, A.

M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
[CrossRef]

Moutin, T.

Obolensky, G.

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

Pegau, W. S.

A. L. Whitmire, E. Boss, T. J. Cowles, and W. S. Pegau, “Spectral variability of the particulate backscattering ratio,” Opt. Express 15, 7019–7031 (2007).
[CrossRef] [PubMed]

W. Wijesekera, W. S. Pegau, and T. J. Boyd, “Effect of surface waves on the irradiance distribution in the upper ocean,” Opt. Express 13, 9257–9264 (2005).
[CrossRef] [PubMed]

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

E. Boss and W. S. Pegau, “Relationship of light scattering at an angle in the backward direction to the backscattering coefficient,” Appl. Opt. 40, 5503–5507 (2001).
[CrossRef]

A. H. Barnard, W. S. Pegau, and J. R. V. Zaneveld, “Global relationships of the inherent optical properties of the oceans,” J. Geophys. Res. 103, 24955–24968 (1998).
[CrossRef]

Perry, M. J.

T. D. Dickey, E. C. Itsweire, M. A. Moline, and M. J. Perry, “Introduction to the limnology and oceanography: special issue on autonomous and Lagrangian platforms and sensors (ALPS),” Limnol. Oceanogr. 53, 2057–2061 (2008).
[CrossRef]

D. L. Rudnick and M. J. Perry, “ALPS: Autonomous and Lagrangian Platforms and Sensors,” Workshop report, www.geo-prose.com/ALPS (Geo Prose, 2003).

Poteau, A.

H. Loisel, X. Mériaux, J.-F. Berthon, and A. Poteau, “Investigation of the optical backscattering to scattering ratio of marine particles in relation with their biogeochemical composition in the eastern English Channel and southern North Sea,” Limnol. Oceanogr. 52, 739–752 (2007).
[CrossRef]

Roesler, C. S.

C. S. Roesler and E. Boss, “In situ measurement of the inherent optical properties (IOPs) and potential for harmful algal bloom detection and coastal ecosystem observations,” in Real-Time Coastal Observing Systems for Ecosystem Dynamics and Harmful Algal Bloom (UNESCO, 2008), pp. 153–206.

Rudnick, D. L.

D. L. Rudnick and M. J. Perry, “ALPS: Autonomous and Lagrangian Platforms and Sensors,” Workshop report, www.geo-prose.com/ALPS (Geo Prose, 2003).

Saino, T.

K. Suzuki, M. Kishino, K. Sasaoka, S. Saitoh, and T. Saino, “Chlorophyll-specific absorption coefficients and pigments of phytoplankton off Sanriku, northwestern north Pacific,” J. Oceanogr. 54, 517–526 (1998).
[CrossRef]

Saitoh, S.

K. Suzuki, M. Kishino, K. Sasaoka, S. Saitoh, and T. Saino, “Chlorophyll-specific absorption coefficients and pigments of phytoplankton off Sanriku, northwestern north Pacific,” J. Oceanogr. 54, 517–526 (1998).
[CrossRef]

Sasaoka, K.

K. Suzuki, M. Kishino, K. Sasaoka, S. Saitoh, and T. Saino, “Chlorophyll-specific absorption coefficients and pigments of phytoplankton off Sanriku, northwestern north Pacific,” J. Oceanogr. 54, 517–526 (1998).
[CrossRef]

Shybanov, E.

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

Stramski, D.

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
[CrossRef]

Strombeck, N.

C. Giardino, V. E. Brando, A. G. Dekker, N. Strombeck, and G. Candiani, “Assessment of water quality in lake Garda (Italy) using Hyperion,” Remote Sens. Environ. 109, 183–195(2007).
[CrossRef]

Sullivan, J. M.

Sundman, L. K.

Suzuki, K.

K. Suzuki, M. Kishino, K. Sasaoka, S. Saitoh, and T. Saino, “Chlorophyll-specific absorption coefficients and pigments of phytoplankton off Sanriku, northwestern north Pacific,” J. Oceanogr. 54, 517–526 (1998).
[CrossRef]

Tarran, G.

A. Cunningham, D. McKee, S. Craig, G. Tarran, and C. Widdicombe, “Fine-scale variability in phytoplankton community structure and inherent optical properties measured from an autonomous underwater vehicle,” J. Mar. Syst. 43, 51–59 (2003).
[CrossRef]

Twardowski, M.

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

Twardowski, M. S.

J. M. Sullivan, M. S. Twardowski, P. L. Donaghay, and S. A. Freeman, “Use of optical scattering to discriminate particle types in coastal waters,” Appl. Opt. 44, 1667–1680(2005).
[CrossRef] [PubMed]

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

Várnai, T.

R. F. Cahalan, M. McGill, J. Kolasinski, T. Várnai, and K. Yetzer, “THOR—Cloud thickness from offbeam lidar returns,” J. Atmos. Ocean. Technol. 22, 605–627 (2005).
[CrossRef]

Westberry, T. K.

Whitmire, A. L.

Widdicombe, C.

A. Cunningham, D. McKee, S. Craig, G. Tarran, and C. Widdicombe, “Fine-scale variability in phytoplankton community structure and inherent optical properties measured from an autonomous underwater vehicle,” J. Mar. Syst. 43, 51–59 (2003).
[CrossRef]

Wijesekera, W.

Yetzer, K.

R. F. Cahalan, M. McGill, J. Kolasinski, T. Várnai, and K. Yetzer, “THOR—Cloud thickness from offbeam lidar returns,” J. Atmos. Ocean. Technol. 22, 605–627 (2005).
[CrossRef]

Zaneveld, J. R. V.

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

A. H. Barnard, W. S. Pegau, and J. R. V. Zaneveld, “Global relationships of the inherent optical properties of the oceans,” J. Geophys. Res. 103, 24955–24968 (1998).
[CrossRef]

J. R. V. Zaneveld, J. C. Kitchen, A. Bricaud, and C. C. Moore, “Analysis of in-situ spectral absorption meter data,” Proc. SPIE 1750, 187–200 (1992).
[CrossRef]

Appl. Opt.

Elsevier Oceanogr. Ser.

N. J. Jerlov, “Marine optics,” Elsevier Oceanogr. Ser. 14, i–xiii, 1–231 (1976).
[CrossRef]

J. Atmos. Ocean. Technol.

R. F. Cahalan, M. McGill, J. Kolasinski, T. Várnai, and K. Yetzer, “THOR—Cloud thickness from offbeam lidar returns,” J. Atmos. Ocean. Technol. 22, 605–627 (2005).
[CrossRef]

J. Geophys. Res.

M. S. Twardowski, E. Boss, J. B. Macdonald, W. S. Pegau, A. H. Barnard, and J. R. V. Zaneveld, “A model for estimating bulk refractive index from the optical backscattering ratio and the implications for understanding particle composition in case I and case II waters,” J. Geophys. Res. 106, 14129–14142(2001).
[CrossRef]

E. Boss, W. S. Pegau, M. Lee, M. Twardowski, E. Shybanov, G. Korotaev, and F. Barantange, “Particulate backscattering ratio at LEO 15 and its use to study particlecomposition and distribution,” J. Geophys. Res. 109, C01014(2004).
[CrossRef]

A. H. Barnard, W. S. Pegau, and J. R. V. Zaneveld, “Global relationships of the inherent optical properties of the oceans,” J. Geophys. Res. 103, 24955–24968 (1998).
[CrossRef]

M. Babin, D. Stramski, G. M. Ferrari, H. Claustre, A. Bricaud, G. Obolensky, and N. Hoepffner, “Variations in the light absorption coefficients of phytoplankton, nonalgal particles, and dissolved organic matter in coastal waters around Europe,” J. Geophys. Res. 108, 3211 (2003).
[CrossRef]

J. Mar. Syst.

A. Cunningham, D. McKee, S. Craig, G. Tarran, and C. Widdicombe, “Fine-scale variability in phytoplankton community structure and inherent optical properties measured from an autonomous underwater vehicle,” J. Mar. Syst. 43, 51–59 (2003).
[CrossRef]

J. Oceanogr.

K. Suzuki, M. Kishino, K. Sasaoka, S. Saitoh, and T. Saino, “Chlorophyll-specific absorption coefficients and pigments of phytoplankton off Sanriku, northwestern north Pacific,” J. Oceanogr. 54, 517–526 (1998).
[CrossRef]

Limnol. Oceanogr.

H. Loisel, X. Mériaux, J.-F. Berthon, and A. Poteau, “Investigation of the optical backscattering to scattering ratio of marine particles in relation with their biogeochemical composition in the eastern English Channel and southern North Sea,” Limnol. Oceanogr. 52, 739–752 (2007).
[CrossRef]

T. D. Dickey, E. C. Itsweire, M. A. Moline, and M. J. Perry, “Introduction to the limnology and oceanography: special issue on autonomous and Lagrangian platforms and sensors (ALPS),” Limnol. Oceanogr. 53, 2057–2061 (2008).
[CrossRef]

M. Babin, A. Morel, V. Fournier-Sicre, F. Fell, and D. Stramski, “Light scattering properties of marine particles in coastal and open ocean waters as related to the particle mass concentration,” Limnol. Oceanogr. 48, 843–859 (2003).
[CrossRef]

Opt. Express

Proc. SPIE

J. R. V. Zaneveld, J. C. Kitchen, A. Bricaud, and C. C. Moore, “Analysis of in-situ spectral absorption meter data,” Proc. SPIE 1750, 187–200 (1992).
[CrossRef]

Remote Sens. Environ.

C. Giardino, V. E. Brando, A. G. Dekker, N. Strombeck, and G. Candiani, “Assessment of water quality in lake Garda (Italy) using Hyperion,” Remote Sens. Environ. 109, 183–195(2007).
[CrossRef]

Rev. Geophys.

T. Dickey, M. Lewis, and G. Chang, “Optical oceanography: recent advances and future directions using global remote sensing and in situ observations,” Rev. Geophys. 44, RG1001(2006).
[CrossRef]

Other

C. S. Roesler and E. Boss, “In situ measurement of the inherent optical properties (IOPs) and potential for harmful algal bloom detection and coastal ecosystem observations,” in Real-Time Coastal Observing Systems for Ecosystem Dynamics and Harmful Algal Bloom (UNESCO, 2008), pp. 153–206.

Z. Lee, “Remote sensing of inherent optical properties: fundamentals, tests of algorithms, and applications,” Tech. Rep. 5 (International Ocean Colour Coordinating Group, 2006).

J. Downing, “An optical instrument for monitoring suspended particulates in ocean and laboratory,” in Proceedings OCEANS ’83 (IEEE, 1983), pp. 199–202.
[CrossRef]

Absorption measurements have been performed using ac-9+ spectrophotometers mounted on very large AUVs . However, because of their size (requiring large vessels for deployment and implying short mission durations), these platforms are not applicable to long-term routine IOP monitoring.

G. R. Fournier and M. Jonasz, “Computer-based underwater imaging analysis,” in Conference on Airborne and In-Water Underwater Imaging (SPIE, 1999), Vol.  3761, pp. 62–70.

C. D. Mobley, Light and Water: Radiative Transfer in Natural Waters, 1st ed. (Academic, 1994).

R. A. Leathers, T. V. Downes, C. O. Davis, and C. D. Mobley, “Monte Carlo radiative transfer simulations for ocean optics: a practical guide,” Memorandum report A426624 (Naval Research Laboratory, 2004).

D. L. Rudnick and M. J. Perry, “ALPS: Autonomous and Lagrangian Platforms and Sensors,” Workshop report, www.geo-prose.com/ALPS (Geo Prose, 2003).

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Figures (9)

Fig. 1
Fig. 1

Photographs of the backscattering spot of a red laser for a series of solutions with increasing concentrations of absorbing (green die) and scattering (Maalox) agents. The camera sensitivity and exposure time were held constant. The radial asymmetry is due to the noncircular laser beam used to illuminate the samples and the slight offset of the laser source and camera.

Fig. 2
Fig. 2

Sketch of the proposed IOP sensor, with typical modeled measurement. A collimated light beam is shone into the water and the backscattered light intensity is retrieved as a function of distance from the center of illumination by three concentric photodetector rings. In the numerical simulation of the detected signal, photons are emitted with assigned weights of 1 and traced through multiple scattering events until their weights fall below a threshold w min or they are detected. The signal is described by the integrated photon weights within each ring as a function of the distance from the center.

Fig. 3
Fig. 3

Particulate absorption and scattering values chosen to drive the radiative transfer simulations used in this study ( λ = 670 nm ). The IOP combinations are derived from the ranges of particulate absorption and scattering measured throughout a wide variety of water masses around Europe and in the North Atlantic and their relationships reported in [26, 27]. These values are in agreement with measurements of a p and b p in coastal and open ocean locations around North America and the equatorial Pacific [30].

Fig. 4
Fig. 4

Graphical representation of the calculation of α for a sample data set ( B p = 0.01 , a p = 0.17 m 1 , b p = 2.9 m 1 ).

Fig. 5
Fig. 5

Water IOPs plotted against resulting signal descriptors: (a) backscattering coefficient versus geometry parameter α, (b) ratio between backscattering and absorption versus detected photon count D. The different colors correspond to different particle backscattering ratios, and the black lines correspond to Eqs. (13, 14), which numerically fit the data.

Fig. 6
Fig. 6

Histograms of the relative errors in inverting (a)  b b and (b) a from modeled instrument response to full range of IOPs.

Fig. 7
Fig. 7

Relative errors in inverting (a)  b b and (b) a plotted against the corresponding total single-scattering albedo values b / c . The different colors indicate numerical experiments with different particle backscattering ratios.

Fig. 8
Fig. 8

Range of shapes of the VSF in the back direction used in this study. (a) Particulate VSF normalized by the particulate backscattering coefficient, (b) total VSF normalized by the total backscattering coefficient. FF stands for Fournier–Forand.

Fig. 9
Fig. 9

Typical cumulative detected photon weight count for a 1 m radius sensor (sample data set obtained with input IOPs: B p = 0.01 , a p = 0.17 m 1 , b p = 2.9 m 1 ).

Tables (7)

Tables Icon

Table 2 Constant IOP Values Used in the Optical Model ( λ = 670 nm )

Tables Icon

Table 3 Inversion Errors for Simulated Detector Responses to Entire Range of IOP Combinations for Different Inversion Algorithms, Obtained with the “Training Data Sets” and Applied on the “Test Data Sets”

Tables Icon

Table 4 Inversion Algorithm Performance on Simulated Response of Detectors of Different Sizes to Entire Range of IOP Combinations

Tables Icon

Table 5 Inversion Algorithm Performance on Simulated Response of Detectors of Different Resolutions to Entire Range of IOP Combinations

Tables Icon

Table 6 Inversion Algorithm Performance on Simulated Detector Response: Comparison between Numerical Experiments Using Different Scattering Phase Functions a

Tables Icon

Table 7 Inversion Algorithm Performance and Detector Response for Instruments Located on the Water Surface versus in the Water, Far from the Surface ( a p = 0.7 m 1 ; b p = 26.34 m 1 )

Equations (20)

Equations on this page are rendered with MathJax. Learn more.

a ( λ ) = a s w ( λ ) + a p ( λ ) + a g ( λ ) ,
b ( λ ) = b s w ( λ ) + b p ( λ ) ,
c ( λ ) = a ( λ ) + b ( λ ) ,
β ˜ F F ( θ ) = 1 4 π ( 1 δ ) 2 δ ν { ν ( 1 δ ) ( 1 δ ν ) + 1 sin 2 ( θ 2 ) [ δ ( 1 δ ν ) ν ( 1 δ ) ] } + δ π ν 1 16 π ( 1 δ π ) δ π ν ( 3 cos 2 θ 1 ) ,
ν = 3 μ 2 , δ = 4 sin 2 ( θ 2 ) 3 ( n 1 ) 2 , δ π = δ ( π ) ,
B p = 1 1 δ π 2 ν + 1 0.5 ( 1 δ π 2 ν ) ( 1 δ π 2 ) δ π 2 ν , δ π 2 = δ ( π / 2 ) ,
2 3 δ π 2 = ( 0.01 0.3084 ν ) 2 .
β s w ( θ ; 670 nm ) = 0.509 ( 1 + 0.835 cos 2 θ ) · 10 4 .
β ˜ = b p · β ˜ F F + β s w b p + b s w .
N ( r ) = 1 N source 2 π 0 t r Δ r 2 r + Δ r 2 n ( r ) r d r d t ,
D = 1 N source 2 π 0 t 1 mm R n ( r ) r d r d t ,
C ( r ) = 1 N source 2 π 0 t 1 mm r n ( r ) r d r d t .
b b = 10 1.048 log ( α ) + 0.3409 .
b b a = 10 0.07407 log 2 ( D ) + 0.3525 log ( D ) + 0.6555 .
b b p = b b b b s w ,
a p g = a a s w .
ε a p g = a a p g · ε a ,
ε b b p = b b b b p · ε b b ,
a p ( 670 ) = a ϕ ( 670 ) + a NAP ( 670 ) .
b p ( 670 ) a p ( 670 ) = ( ω p 1 1 ) 1 .

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