Accession Number : ADA291386

Title :   Optical Cross-Sections of Marine Particles.

Descriptive Note : Final technical rept. FY-93,

Corporate Author : UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF BIOLOGICAL SCIENCES

Personal Author(s) : Stramski, Dariusz ; Kiefer, Dale A.

PDF Url : ADA291386

Report Date : 1993

Pagination or Media Count : 10

Abstract : Our objective is to conduct a comprehensive study of the optical properties of marine microorganisms and other biogenic particles in order to determine their optical cross-sections and contribution to absorption and scattering by sea water. Our major effort during the last year was aimed at quantifying diel changes in scattering and absorption cross-sections of phytoplankton cells. This study is related to our hypothesis that the relatively large diel cycle in the beam attenuation coefficient that has been observed in the ocean is in part caused by diel change in the size and refractive index of cells comprising the phytoplankton community. Another effort was focused on testing the applicability of the dynamic light scattering (DLS) technique for characterizing the size distribution of small marine particles (< 5 microns) including the submicron range. While we previously used this technique for studying the cultures of heterotrophic marine bacteria, this time we focus our attention on natural assemblages of marine particles. This effort is related to the hypothesis that submicron particles make major contribution to particulate backscattering in the ocean. Another major effort was aimed at examining marine cyanobacteria which represent small autotrophic organisms from the picoplankton size range. We also assessed the effect of gas microbubbles on light scattering in the upper ocean. (AN)

Descriptors :   *OPTICAL CROSS SECTIONS, *MARINE BIOLOGY, LIGHT SCATTERING, OPTICAL PROPERTIES, EXPERIMENTAL DATA, LABORATORY TESTS, COMMUNITIES, OCEAN SURFACE, BACTERIA, SCATTERING CROSS SECTIONS, REFRACTIVE INDEX, PARTICLE SIZE, BACKSCATTERING, MIE SCATTERING, OPTICAL ANALYSIS, ATTENUATION, PARTICULATES, HYPOTHESES, ABSORPTION CROSS SECTIONS, SEA WATER, OCEAN MODELS, CULTURES(BIOLOGY), PHYTOPLANKTON, CELL STRUCTURE.

Subject Categories : Biological Oceanography
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE