Light backscattering by randomly oriented hexagonal ice crystals of cirrus clouds is considered within the framework of the physical-optics approximation. The fine angular structure of all elements of the Mueller matrix in the vicinity of the exact backward direction is first calculated and discussed. In particular, an approximate equation for the differential scattering cross section is obtained. Its simple spectral dependence is discussed. Also, a hollow of the linear depolarization ratio around the exact backward direction inherent to the long hexagonal columns is revealed.
© 2013 Optical Society of America
Original Manuscript: May 20, 2013
Revised Manuscript: July 10, 2013
Manuscript Accepted: July 10, 2013
Published: July 30, 2013
Anatoli Borovoi, Alexander Konoshonkin, and Natalia Kustova, "Backscattering by hexagonal ice crystals of cirrus clouds," Opt. Lett. 38, 2881-2884 (2013)