Abstract

Increased scattering by seawater relative to that by pure water is primarily due to additional fluctuation of the refractive index contributed by sea salts. Salts with different ionic weight and sizes, while barely affecting the scattering that is due to density fluctuations, have a significant effect on the scattering that is due to concentration fluctuations. And this explains the major differences of their total scattering that would be observed. Scattering by solutions of NaCl, the major sea salt, is consistently about 6.7% and 4% lower than seawater of the same mass concentration and of the same refractive index, respectively. Because of ionic interactions, the molecular scattering does not follow the simple addition rule that applies to bulk inherent optical properties, with the total less than the summation of the parts. The possible values of scattering by waters of, such as, Dead Sea or Orca Basin, which have different salt composition from seawater, are discussed.

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History
Original Manuscript: August 4, 2009
Manuscript Accepted: October 9, 2009
Published: October 14, 2009

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Author Affiliations

Xiaodong Zhang

Department of Earth System Science and Policy, University of North Dakota, Grand Forks, ND 58202, USA

Lianbo Hu

Department of Earth System Science and Policy, University of North Dakota, Grand Forks, ND 58202, USAOcean Remote Sensing Institute, Ocean University of China, Qingdao, 266001, China

Michael S. Twardowski, James M. Sullivan

Wet Labs Inc., 70 Dean Knauss Dr, Narragansett, RI 02882, USA

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