Oral Session 4

Extensive in situ measurements of absorption, backscattering, and polarized angular scattering to improve particle-type algorithms

The Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission is now delivering unprecedented hyperspectral radiometry and polarimetry measurements of the global ocean. Radiometry from PACE’s Ocean Color Instrument will reveal new dimensions of ocean biogeochemistry, and could be complemented by polarimetry, yet limited work has been done to integrate these sensing modalities and establish robust connections between measurements of ocean leaving degree of linear polarization (DoLP) and marine particle properties. A LISST-Horizon, a new instrument that measures polarized scattering at 60 angles (0.03° to 160°) using a green laser (520nm) source, was recently deployed on a scientific cruise in a flow-through system concurrently with an IOP suite and automated microscopy (IFCB). The cruise sailed along the eastern coast of South America down to Antarctica, transiting the South Atlantic to South Africa, and up the west coast of Africa to Angola encountering particulate populations spanning from single species dominance to dominance by inorganic sediments. This work uses this new instrument to explore relationships between marine particles properties and measurements of DoLP and IOPs. We focus on periods of nearly monospecific phytoplankton communities to investigate potential algorithms to retrieve phytoplankton groups from DoLP and IOPs. Preliminary work suggests that dinoflagellates, coccolithophores, diatom chains, and detritus dominated populations can be distinguished based on DoLP metrics alone.

Patrick Gray, University of Maine, USA, https://orcid.org/0000-0002-8997-5255

John Smith, NASA Langley Research Center, https://orcid.org/0000-0001-6066-793X

Code of Conduct