AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Universal Description of Light Scattering by Atmospheric Ice Crystals
YULI HEINSON, Justin Maughan, Ping Yang, Amit Chakrabarti, Jiachen Ding, Chris Sorensen, Kansas State University
Abstract Number: 108 Working Group: Aerosol Physics
Abstract Q-space analysis is applied to the scattering phase functions associated with various shapes of ice crystals. The present analysis involves displaying the scattered intensity as a function of q or qR, on a log-log scale, where q=2ksin(theta⁄2) and 2R is the characteristic dimension of the particle. The analysis uncovers common patterns for all ice crystal shapes, patterns which are quite similar to the counterparts found for spheres. Specifically, a q-independent forward scattering lobe is followed by the Guinier regime which is then followed by a -3 slope regime due to 2D Fraunhofer diffraction, a transition regime, and then a -4 slope regime due to 3D diffraction. An enhanced back scattering regime is sometimes observed. Aggregates of ice crystals show a single power law with an exponent of about -2 along with the diminishing glory in the backward direction. The Rayleigh normalized forward scattering intensity, in which approximately half of the scattered light resides, is found to scale with the internal coupling parameter rho$^' with a power law with an exponent of -2.