Abstract
Lidar technologies are widely used for retrieving microphysics of cirrus clouds, i.e. sizes, shapes and spatial orientation of ice crystals constituting the clouds. Interpretation of the lidar signals are based on the backscattered light. However, properties of the light backscattered by the ice crystals have not been well known and understood yet. The reason of this is that the problem of light scattering by the ice crystals much larger that incident wavelengths has not been solved satisfactorily yet because of great demands to computer resources. In this contribution we review the physical optics approximation as a prospective method to solve the light scattering problem on large nonspherical particles in lidar application.
Highlights
There are several recently developed numerical exact methods based on the Maxwell equations like the PSDT and II-TM [1,2]
The maximum size parameter achieved within the numerical exact methods is reported as large as 100 in [1] and 130 in [2] while in natural cirrus clouds this parameter runs up to several thousands
Within the physical optics method we have found the solution of the light scattering problem by ice crystal particles of cirrus clouds for particles with size varied from 10 to 1000 ȝm at wavelengths from 0.355 to 1.6 ȝm
Summary
There are several recently developed numerical exact methods based on the Maxwell equations like the PSDT (pseudo-spectral time domain method) and II-TM (invariant imbedding T-matrix method) [1,2]. The maximum size parameter achieved within the numerical exact methods is reported as large as 100 in [1] and 130 in [2] while in natural cirrus clouds this parameter runs up to several thousands In this contribution, a review of the backscattered data obtained by the physical-optics approximation is proposed. One of the discussed topics is existence of a sharp peak around the backward scattering direction in the phase function of cirrus clouds Earlier, such a peak was predicted within the physical-optics approximation [3]. The microphysics is inferred from the backscatter ratios: the depolarization, color, and lidar (extinction-to-backscatter) ratios These quantities are main sources of information about size, shape and spatial orientation of the crystals [4]. These ratios are reviewed in application to the scanning and tilted lidars
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
