Extinction Coefficients for Multimodal Atmospheric Particle Size Distributions
نویسندگان
چکیده
A chart was developed which gives the volume-normalized extinction coefficient for log-normally modelled, multimodal particle volume distributions. The real part of the particle refractive index ranges from 1.30 to 1.70. Two adjustment charts modify the main chart for an imaginary part of the refractive index different from 0.02, and for a geometric standard deviation of the modal volume distribution, different from 2.0. The charts show that particles in the accumulation range, which has a mode in the 0.1 to 1 m diameter size interval, are optically the most active. Exact knowledge of the particle refractive index is imperative for fine particles, but of small importance for coarse particles.
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