Instrument for Measurement of Oceanic Particle Size Distribution from Submicron to Mesoplankton

Particle size distribution (PSD) is a fundamental environmental measurement, with diverse biogeochemical applications including carbon cycle science, ecosystem and fisheries modeling, and harmful algal bloom (HAB) detection/prediction. There is optimism that estimates of PSD will be available from ocean color measurements (such as NASA's upcoming PACE mission), and will be able to help constrain global-scale ecosystem/carbon models and estimates of primary production. However, natural PSD variability is not well understood due to the challenges of routine measurement, and there exists little field data over large space and time scales. We propose to bridge this gap by investigating an instrument for ship-based flow-through application that uses laser scattering from multiple wavelengths and polarizations for estimation of the PSD across a wide range of particle sizes from submicron to >200 micron, covering a range from the smallest oceanic pico-plankton to larger meso-plankton.