Light‐scattering Vectors of Some Marine Particles1

The volume‐scattering function and particle size distribution of several marine sediments and species of phytoplankton were measured. The volume‐scattering function of a single particle at a 45° scattering angle, β̄ 45 was computed. In general, increases in S̄ accompany increases in β̄ 45 for the biological material over the size range of particles measured (10–70 µ 2 ). The geological samples displayed a wide range of specific scattering over the much narrower area range studied (5–15 µ 2 ). The specific volume‐scattering function and the mean particle area form a two‐dimensional optical vector( β̄ 45 , S̄ ) which can be used to characterize the suspended material in seawater. Vertical profiles of the optical vector measured in the eastern equatorial Pacific and off the Oregon coast show surface values that appear to be in the biological section of the optical vector diagram and a smooth transition to the apparent geological portion of the diagram with depth.