Journal ArticleDOI
Interpretation of airborne oceanic lidar: effects of multiple scattering
TLDR
The effects of multiple scattering on the interpretation of the time dependence of elastic backscattering of laser pulses from the ocean (lidar) are investigated through solving the radiative transfer equation by Monte Carlo techniques.Abstract:
The effects of multiple scattering on the interpretation of the time dependence of elastic backscattering of laser pulses from the ocean (lidar) are investigated through solving the radiative transfer equation by Monte Carlo techniques. In particular, after removal of the geometric loss factors, it is found that the backscat-tered power is a decaying exponential function of time, over the time interval required for photons to travel four attenuation lengths through the water. The effective attenuation coefficient of this exponential decay is found to be strongly dependent on the parameters of the lidar system and on the optical properties of the water. The significant parameter is the ratio of the radius of the spot on the sea surface viewed by the lidar receiver optics to the mean free path of photons in the water. For values of this parameter near zero, the decay is determined by the beam attenuation coefficient, while for values greater than ~5-6, the decay is given by the attenuation coefficient for downwelling irradiance, often referred to as the diffuse attenuation coefficient. Between these two extremes the interpretation of the effective attenuation coefficient requires, essentially, complete knowledge of the inherent optical properties of the water: the beam attenuation coefficient and the volume scattering function.read more
Citations
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Meeting the accuracy challenge in airborne lidar bathymetry
TL;DR: The U.S. Army Corps of Engineers SHOALS project as mentioned in this paper is a successful airborne lidar bathymetry system that has been operated from both a helicopter and a fixed-wing aircraft for charting, dredging, coastal engineering, resource management, modeling, and reconnaissance.
Journal ArticleDOI
Review of profiling oceanographic lidar
TL;DR: A review of the development of oceanographic lidars can be found in this paper, where the authors provide quantitative profiles of the optical properties of the water column to depths of 20 to 30m in productive coastal waters and to depths depths of 100m for a blue lidar in the open ocean.
Journal ArticleDOI
Spaceborne Lidar in the Study of Marine Systems.
Chris A. Hostetler,Michael J. Behrenfeld,Yongxiang Hu,Johnathan W. Hair,Jennifer A. Schulien +4 more
TL;DR: A review of the lidar technique, its applications in marine systems, a perspective on what can be accomplished in the near future with an ocean- and atmosphere-optimized satellite lidar, and a vision for a multiplatform virtual constellation of observational assets that would enable a three-dimensional reconstruction of global ocean ecosystems are presented.
Journal ArticleDOI
Lidar fluorosensing of mineral oil spills on the sea surface
Theo Hengstermann,Rainer Reuter +1 more
TL;DR: Airborne fluorosensor measurements over maritime oil spills show that this method enables a sensitive classification and quantification of surface films having a thickness in the 1-microm range, however, significant changes of the optical signature of oil occur in the presence of submicrometer films which are not yet fully understood.
Journal ArticleDOI
The beam attenuation to chlorophyll ratio: an optical index of phytoplankton physiology in the surface ocean?
TL;DR: In this article, the authors used five historical field data sets to directly compare spatial and temporal variability in particulate beam attenuation coefficient (c p ) with two independent indices of photoacclimation: the light-saturated, chlorophyll-normalized photosynthetic rate, P b opt, and the light saturation index, E k.
References
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Journal ArticleDOI
Computed relationships between the inherent and apparent optical properties of a flat homogeneous ocean.
TL;DR: Monte Carlo simulations of the transfer of radiation in the ocean are used to compute the apparent optical properties of a flat homogeneous ocean as a function of the inherent optical properties and it is shown that these relations can be used with measurements of the upwelling and downwelling irradiance, the beam attenuation coefficient, and the incident radiance distribution.
Journal ArticleDOI
Nimbus-7 coastal zone color scanner: system description and initial imagery.
Warren A. Hovis,Dennis K. Clark,F. Anderson,Roswell W. Austin,W. H. Wilson,Edward T. Baker,D. Ball,Howard R. Gordon,James L. Mueller,S. Z. El-Sayed,B. Sturm,Robert C. Wrigley,Charles S. Yentsch +12 more
TL;DR: Initial imagery confirms that CZCS data can be processed to a level that reveals subtle variations in the concentration of phytoplankton pigments, which has potential applications for the study of large-scale patchiness in phy toplankon distributions, the evolution of spring blooms, water mass boundaries, and mesoscale circulation patterns.
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Phytoplankton Pigments from the Nimbus-7 Coastal Zone Color Scanner: Comparisons with Surface Measurements
TL;DR: The removal of atmospheric effects from Nimbus-7 Coastal Zone Color Scanner (CZCS) images reveals eddy-like ocean turbidity patterns not apparent in the original calibrated images.
Journal ArticleDOI
Use of water Raman emission to correct airborne laser fluorosensor data for effects of water optical attenuation.
TL;DR: In this application to remotely monitor chlorophyll a concentrations in fresh waters, the Raman-corrected chlorophyLL a fluorescence measurements were found to be highly correlated with chlorophyh a ground truth data.
Journal ArticleDOI
Application of an airborne pulsed laser for near shore bathymetric measurements
G. Daniel Hickman,John E. Hogg +1 more
TL;DR: In this article, a feasibility investigation of the deployment of a pulsed blue-green laser as an airborne bathymetric sensor for near-shore beach reconnaissance has been performed.