A study of amorphous aerosol and ice particles in the Earth's atmosphere with polarization measurements

Unlike crystals, amorphous solid particles do not have the long-range order (e.g., hydrogen-bond in ice). Organic substances tend to transition into amorphous phase (viscous secondary organic aerosols) upon drying of aqueous droplets (Mikhailov et al., 2017). There were studies suggesting that amorphous water/ice particles exist in the atmosphere as well (e.g., Nevzorov 2006; Murray et al., 2015). One of the key feature of these amorphous aerosol and cloud particles is the so-called "negative polarization" (polarization perpendicular to scattering plane) in near-backscatter angles. Here we will briefly introduce the optical properties of these particles and preliminary ob-servational studies using existing POLDER measurements. We will also briefly introduce a NASA/KASI CubeSat polarimeter concept that can provide most favorable viewing geometry for making these measurements.

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