A new method for measuring optical scattering properties of atmospherically relevant dusts using the Cloud and Aerosol Spectrometer with Polarization (CASPOL)

Abstract. Atmospheric aerosols have major impacts on regional and global climate through scattering and absorption of solar radiation. A new instrument, the Cloud and Aerosol Spectrometer with Polarization (CASPOL) from Droplet Measurement Technologies measures light scattered by aerosols in the forward (4° to 12°) and backward (168° to 176°) directions, with an additional polarized detector in the backward direction. Scattering by a single particle can be measured by all three detectors for aerosols in a broad range of sizes, 0.6 μm −10 cm −2 ) and hematite (4.1 × 10 −9 cm −2 ).